Metrology system with position and orientation tracking utilizing pattern of light beam

Abstract

To provide a metrology system that is provided for use with a movement system that moves an end tool.SOLUTION: The metrology system includes a sensor configuration, a light beam source configuration and a processing portion. The light beam source configuration directs a first pattern of light beams and a second pattern of light beams to light beam sensors to indicate a position and orientation of the light beam source configuration. The first pattern of light beams has a lower density of light beams as compared to the second pattern of light beams. Measurement signals from the light beam sensors are processed to determine a position and orientation of the light beam source configuration. The first pattern light beams and the second pattern light beams have at least one different characteristic (e.g., wavelength, polarity, timing, etc.) that enables the first pattern light beams to be distinguished from the second pattern light beams.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a measurement and movement system, and more particularly, to a measurement system used with a movement system, such as a robot, that tracks position and orientation.

Background Art

[0002] In manufacturing, workpiece inspection, and other processes, robotic movement systems that perform specific functions are frequently used. For example, a robotic system or other movement system can be utilized to move an end tool to perform a specific operation (e.g., with respect to workpiece inspection, manufacturing, etc.). In some applications, various types of robots that can be used include Articulated Robots, Selective Compliance Assembly Robot Arms (SCARA) robots, Cartesian Robots, Cylindrical robots, Spherical Robots, and the like. As an example of a component included in a robot, a SCARA robot system (which may be a type of articulated robot system, for example) may typically have a base, a first arm portion rotatably coupled to the base, and a second arm portion rotatably coupled to the end of the first arm portion. In various configurations, the end tool may be coupled to the end of the second arm portion (e.g., to perform a certain operation and / or inspection operation). Such a system may include a position sensor (e.g., a rotary encoder) that is used to determine / control the positioning of the arm portion and accordingly the positioning of the end tool. In various embodiments, the positioning accuracy of such a system is limited by certain factors (e.g., the performance of the rotary encoder combined with the mechanical stability of the robot system), but is about 100 microns.

[0003] U.S. Patent No. 4,725,965, which is incorporated herein by reference in its entirety (referred to herein as the '965 patent), discloses several calibration techniques for improving the accuracy of a SCARA system. As described in the '965 patent, to calibrate the kinematic model, the arm portion is placed in a first configuration where the end tool is positioned above a fixed reference point. Next, the arm portion is placed in a second angular configuration and nominally positioned such that the end tool is re-aligned with the reference point. The error in the kinematic model is calculated from the displacement of the end tool from the reference point when the arm portion is switched from the first angular configuration to the second angular configuration. Then, the kinematic model is corrected according to the calculated error. The procedure is repeated until the error reaches zero, at which point the kinematic model of the SCARA robot is considered calibrated. As further explained in the '965 patent, the calibration technique may include the use of a specific camera.

[0004] Techniques such as those described in the '965 patent may be utilized to calibrate a robotic system, but the use of such techniques (e.g., may require a lot of time and / or may not be able to provide the desired level of accuracy for all possible orientations of the robot during certain operations) may not be very desirable in certain applications. A system that can improve such problems (e.g., improve the reliability, reproducibility, speed, etc. of position and orientation determination for processes such as workpiece measurement, manufacturing, etc.) is desired. SUMMARY OF THE INVENTION

[0005] This summary is provided to introduce, in a simplified form, a selected choice of concepts that are further described below in the detailed description of the invention. This summary is not intended to identify key features of the claimed subject matter nor is it intended to be used as an aid in determining the scope of the claimed subject matter.

[0006] According to one aspect, a measurement system is provided for use with a movement system that moves an end tool. The movement system includes a movable structure and an operation control system. The movable structure includes an end tool attachment structure configured to attach the end tool. The operation control system is configured to control the position and orientation of the end tool based at least in part on controlling the movable structure to move at least a portion of the end tool attached to the end tool attachment structure within a movement volume.

[0007] The measurement system includes a sensor structure, a light beam source structure, and a processing unit. The sensor structure includes a plurality of light beam sensors arranged at fixed positions, including a first light beam sensor at at least a first position and a second light beam sensor at a second position. The light beam source structure is configured to direct a first pattern of light beams and a second pattern of light beams toward the light beam sensors of the sensor structure to indicate the position and orientation of the light beam source structure.

[0008] The light beam source structure is configured to be coupled to at least one of the end tool or the end tool attachment structure. At least a portion of the light beam directed toward and received by the light beam sensor is configured to generate a measurement spot on the light beam sensor, whereby the light beam sensor generates a corresponding measurement signal. The first pattern of light beams has a lower density of light beams compared to the second pattern of light beams having a higher density of light beams of the second pattern of light beams. The processing unit is configured to process the measurement signals from the light beam sensors of the sensor structure to determine the position and orientation of the light beam source structure.

[0009] The measurement system is configured such that at least a first position of the light beam source structure is at a first distance from the first light beam sensor and at a second distance from the second light beam sensor, and the second distance is greater than the first distance. One or more first pattern light beams directed towards the first light beam sensor are utilized to cause the first light beam sensor to generate a measurement signal for processing by the processing unit. A second pattern light beam directed towards the first light beam sensor is not utilized to cause the first light beam sensor to generate a measurement signal for processing by the processing unit (e.g., in various embodiments, the second pattern light beam and / or the signal generated thereby is at least blocked, filtered, not selected, or otherwise not utilized). Further, one or more second pattern light beams BP2LB directed towards the second light beam sensor are utilized to cause the second light beam sensor to generate a measurement signal for processing to determine position and orientation. In various implementations, the first pattern light beam and the second pattern light beam have at least one different characteristic that can distinguish the first pattern light beam from the second pattern light beam (e.g., wavelength, polarity, timing, etc.).

[0010] According to another aspect, a method of operating a measurement system including an optical beam source structure is provided. The method includes operating the optical beam source structure to direct a first pattern of an optical beam and a second pattern of the optical beam toward an optical beam sensor of a sensor structure, indicating a position and an orientation of the optical beam source structure. The first pattern of the optical beam has a lower density of the first pattern optical beam compared to the second pattern of the optical beam having a higher density of the second pattern optical beam. The method further includes processing a measurement signal from the optical beam sensor of the sensor structure to determine the position and the orientation of the optical beam source structure, wherein at least a first position of the optical beam source structure is at a first distance from a first optical beam sensor and at a second distance from a second optical beam sensor, and in a case where the second distance is greater than the first distance, i) one or more first pattern optical beams directed toward the first optical beam sensor are utilized to cause the first optical beam sensor to generate a measurement signal for processing to determine the position and the orientation, ii) a second pattern optical beam directed toward the first optical beam sensor is not utilized to cause the first optical beam sensor to generate a measurement signal for processing to determine the position and the orientation (e.g., in various embodiments, the second pattern optical beam and / or a signal generated thereby is at least blocked, filtered, not selected, or otherwise not utilized), iii) one or more second pattern optical beams directed toward the second optical beam sensor are utilized to cause the second optical beam sensor to generate a measurement signal for processing to determine the position and the orientation.

[0011] In various embodiments, the method further includes receiving position information from a movement system that moves an end tool, wherein the position information from the movement system indicates, with a movement system accuracy, the first distance of the optical beam source structure from the first optical beam sensor, and a second pattern optical beam directed toward the first optical beam sensor based at least in part on the first distance indicated by the position information from the movement system is not utilized to cause the first optical beam sensor to generate a measurement signal for processing to determine the position and the orientation.

Brief Description of the Drawings

[0012]

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Best Mode for Carrying Out the Invention

[0013] FIG. 1 is a block diagram of a first exemplary embodiment of a mobile measurement system 100 that includes a mobile system 110 and a measurement system 150. The mobile system 110 (e.g., a multi-joint robot) includes a movable structure MAC (e.g., a movable arm configuration) and an operation control processing system 140. The measurement system 150 includes a sensor structure 160, an optical beam source structure LC, and a measurement system position orientation processing unit 190. In the configuration of FIG. 1, the optical beam source structure LC (illustrated as directing, e.g., an arrowed optical beam in different directions including the direction toward the optical beam sensors S1 and S2) is coupled to the end tool ETL. As will be described in more detail below, the measurement system 150 can be utilized to track the position and orientation (e.g., of the end tool ETL as moved by the mobile system 110).

[0014] In the example of FIG. 1, the movable structure MAC includes a lower base portion BSE, arm portions 121-125, motion mechanisms 131-135, position sensors SEN1-SEN5, and an end tool attachment structure ETMC. In various embodiments, some or all of the arm portions 121-125 may each have a proximal end thereof attached to respective ones of the motion mechanisms 131-135. In the example of FIG. 1, some or all of the motion mechanisms 131-135 (e.g., rotary joints having corresponding motors) enable motion (e.g., rotation) of respective ones of the arm portions 121-125 (e.g., about respective rotation axes RA1-RA5). In various embodiments, the position sensors SEN1-SEN5 (e.g., rotary encoders) may be utilized to determine the position (e.g., angular orientation) of respective ones of the arm portions 121-125.

[0015] In various embodiments, the movable structure MAC may have a portion designated as a distal end portion (e.g., the fifth arm portion 125). In the exemplary configuration of FIG. 1, the end tool attachment structure ETMC is located proximate to (e.g., at) the distal end of the fifth arm portion 125 corresponding to the distal end of the movable structure MAC (e.g., designated as the distal end portion). In various alternative embodiments, the distal end portion of the movable structure is not an arm portion, but at least a part of the distal end portion may be an element (e.g., a rotatable element, etc.) corresponding to the distal end of the movable structure where the end tool attachment structure ETMC is disposed.

[0016] In various embodiments, the end tool attachment structure ETMC may include various elements for coupling and maintaining the end tool ETL proximate to the distal end of the movable structure MAC. For example, in various embodiments, the end tool attachment structure ETMC can include automatic coupling connectors, magnetic coupling portions, and / or other coupling elements known in the art for attaching the end tool ETL to the corresponding element. The end tool attachment structure ETMC may also include electrical connections (e.g., power connections, one or more signal lines, etc.) for supplying power to and / or transmitting and receiving signals to at least a part of the end tool ETL (e.g., the end tool sensing portion ETSN).

[0017] In various embodiments, the end tool ETL can include an end tool detection portion ETSN and an end tool stylus ETST having a contact point CP (e.g., that contacts the surface of the workpiece WP). The fifth motion mechanism 135 is disposed proximate to the distal end of the fourth arm portion 124. In various embodiments, the fifth motion mechanism 135 (e.g., a rotary joint having a corresponding motor) may be configured to rotate the fifth arm portion 125 about a rotation axis RA5. In some embodiments, the fifth motion mechanism 135 may alternatively or additionally include a different type of motion mechanism (e.g., a linear actuator) configured to linearly move (e.g., up and down) the fifth arm portion 125. In any case, the end tool ETL is attached (e.g., coupled) to an end tool mounting structure ETMC and has a corresponding end tool position ETP having corresponding coordinates (e.g., x, y, and z coordinates). In various embodiments, the end tool position ETP can correspond to or be proximate to the position of the end tool mounting structure ETMC (e.g., the distal end DE5 of the fifth arm portion 125 or proximate thereto corresponding to the distal end of the movable structure MAC).

[0018] FIG. 2 is a block diagram of a control processing unit 200 of the system of FIG. 1, including an operation control system 140 (which may be a processing system, for example) and including at least a part of an external control system ECS. The operation control processing system 140 is configured to control an end tool position ETP of an end tool ETL at an accuracy level defined as a moving system accuracy. More specifically, the operation control processing system 140 is generally configured to control coordinates (for example, x, y, and z coordinates) of the end tool position ETP at the moving system accuracy, at least partially based on using operation mechanisms 131-135 and position sensors SEN1-SEN5 for detecting and controlling positions of the arm parts 121-125. In various embodiments, the operation control processing system 140 includes operation mechanism control detection units 141-145, each of which can receive signals from the position sensors SEN1-SEN5, detect positions (for example, angular positions, linear positions, etc.) of the respective arm parts 121-125, and / or provide control signals for moving the respective arm parts 121-125 to the respective operation mechanisms 131-135 (including motors, linear actuators, etc.).

[0019] The motion control processing system 140 may also receive a signal from the end tool detection unit ETSN. In various embodiments, the end tool detection unit ETSN may include circuitry and / or configurations related to the operation of the end tool ETL (e.g., for detecting the workpiece WP, etc.). As will be described in detail later, in various embodiments, the end tool ETL (e.g., touch probe, scanning probe, camera, etc.) may be used to contact or otherwise detect surface positions / locations / points on the workpiece WP, and for that purpose, various corresponding signals may be received, determined, and / or processed by the end tool detection unit ETSN and provided to the motion control processing system 140. In various embodiments, the motion control processing system 140 may include an end tool control detection unit 146 that can provide a control signal to the end tool detection unit ETSN and / or receive a detection signal from the end tool detection unit ETSN. In various embodiments, the end tool control detection unit 146 and the end tool detection unit ETSN may be integrated and / or indistinguishable. In various embodiments, the motion mechanism control detection units 141-145 and the end tool control detection unit 146 all provide an output to, and / or receive a control signal from, a motion system position and orientation processing unit 147 that controls and / or determines the overall position and orientation of the movable structure MAC of the motion system 110 and the corresponding position and orientation of the end tool ETL as part of the motion control processing system 140. In various embodiments, the position of the end tool ETL may be referred to as the end tool position ETP. Generally, the motion control system 140 is configured to control the position and orientation of the end tool, at least in part based on controlling the movable structure MAC to move at least a portion of the end tool ETL attached to the end tool mounting structure ETMC within the moving volume MV.

[0020] In various embodiments, the measurement system 150 may be included in or otherwise added to the mobile system 110 (e.g., as part of a retrofit structure for addition to an existing mobile system 110). Generally, the measurement system 150 may be utilized to provide determination of the position and orientation of the end tool ETL (e.g., with an improved accuracy compared to the accuracy of the mobile system 110). More specifically, as will be described in more detail below, the measurement system 150 may be utilized to determine the measured position coordinates of the end tool position ETP and the relative position indicating the orientation of the end tool ETL with an accuracy higher than the accuracy of the mobile system.

[0021] In various embodiments, the sensor structure 160 of the measurement system 150 includes optical beam sensors S1 - S4. In FIG. 1, the optical beam sensors S1 and S2 are shown at the left and right ends, respectively, of the illustrated cross-sectional view, and the general positions of the optical beam sensors S3 and S4 (e.g., located outside and inside the page, respectively) are indicated by dashed lines. As will be described in more detail below, FIG. 4(a) shows a three-dimensional view of a sensor structure 160 - 4A having four optical beam sensors and a structure similar to the sensor structure 160 of FIG. 1.

[0022] The optical beam sensors S1 - S4 are disposed at fixed positions that at least partially define the measurement frame volume MFV (e.g., may be disposed on a frame, wall, or other structure, respectively). The measurement frame volume MFV is configured to be located around at least a portion of the moving volume MV (e.g., at least a portion of the end tool ETL is moved by the mobile system 110). The optical beam source structure LC is configured to operate (e.g., by the optical beam source control unit 192) to direct an optical beam towards the optical beam sensors S1 - S4 of the sensor structure 160 (e.g., indicating the position and orientation of the optical beam source structure LC).

[0023] The optical beam source structure LC is configured to be coupled to at least one of the end tool ETL and the end tool mounting structure ETMC. When the end tool ETL is coupled to the end tool mounting structure ETMC, it will then be understood that the optical beam source structure LC is coupled to both the end tool ETL and the end tool mounting structure ETMC. The position and orientation of the optical beam source structure LC indicate the position and orientation of the end tool ETL. As will be described in more detail below with respect to FIGS. 5A(a) - 5B(h), the optical beams directed towards the optical beam sensors S1 - S4 are configured to generate a measurement spot SP on the position of the optical beam sensor that causes the corresponding optical beam sensor to generate a measurement signal. The measurement system position and orientation processing unit 190 is configured to process the measurement signals from the optical beam sensors S1 - S4 of the sensor structure 160, and the measurement signals from the optical beam sensors S1 - S4 indicate the position and orientation of the optical beam source structure LC and the corresponding position and orientation of the end tool ETL.

[0024] In various embodiments, the moving volume MV consists of a volume in which at least a part of at least one of the end tool ETL and / or the optical beam source structure LC can move. In the example of FIG. 1, the moving volume MV is shown as including the volume in which the contact point CP of the end tool ETL can move when inspecting the workpiece. As an alternative example, the moving volume may alternatively include the volume in which the optical beam source structure LC can move when the end tool ETL is moved to inspect the workpiece. In various embodiments, the movement system 110 is configured to move the movable structure MAC so as to move at least a part of the end tool ETL (including, for example, the contact point CP) attached to the end tool mounting structure ETMC along at least two dimensions (for example, the x and y dimensions) within the moving volume MV. In the example of FIG. 1, the part of the end tool ETL (for example, the contact point CP) is movable along three dimensions (for example, the x, y, and z dimensions) by the movement system 110.

[0025] In various embodiments, the latch unit 181 and / or the measurement system orientation processing unit 190 and / or the optical beam source structure control unit 192 may be included as part of an external control system ECS (e.g., as part of an external computer). The optical beam source structure control unit 192 can supply power and / or control signals to the optical beam source structure LC and / or a part thereof (e.g., one or more optical beam sources of the optical beam source structure LC). The latch unit 181 may be included as part of the sensor structure control processing unit 180 (e.g., the sensor structure control processing unit 180 may supply power to the optical beam sensors S1 to S4 of the sensor structure 160, and / or receive measurement signals therefrom, and / or supply control signals thereto, and may supply such signals and / or transmit and receive other signals to and from the measurement system orientation processing unit 190).

[0026] In various embodiments, the latch unit 181 is configured to: i) input at least one input signal related to the end tool position ETP, ii) determine the timing of a trigger signal based on the at least one input signal, and iii) output the trigger signal to at least one of the measurement system orientation processing unit 190 or the optical beam sensors S1 to S4 of the sensor structure 160. In various embodiments, the measurement system orientation processing unit 190 and / or the sensor structure 160 are configured to determine the current measurement signals from the optical beam sensors S1 to S4 in response to the reception of the trigger signal (e.g., as corresponding to the current position and orientation of the optical beam source structure LC and / or the end tool ETL). In various embodiments, the measurement system orientation processing unit 190 is configured to process the measurement signals to correspond to the timing of the trigger signal to determine the position and orientation of the optical beam source structure LC and / or the end tool ETL at the time of the trigger signal.

[0027] In various embodiments, once the position and orientation of the light beam source structure LC are determined, correspondingly, the position and orientation of the end tool may be determined (e.g., according to known geometric relationships, relative positioning, offsets, etc. between the light beam source structure LC and the end tool ETL). In various embodiments, the light beam source structure LC may be directly attached to the end tool ETL (e.g., such that the gap between the end tool ETL and the light beam source structure LC is minimized or non - existent), or attached to or very close to the end tool attachment structure. In the embodiment of FIG. 1, the light beam source structure LC is shown as being at or at least proximate to the end tool position ETP (e.g., the designated reference position of the end tool ETL). Such a configuration reduces the complexity or improves the accuracy when calculating the position and orientation of the end tool ETL based on the determined position and orientation of the light beam source structure LC.

[0028] In various embodiments, the determination of the position and orientation of the end tool ETL may also be utilized when determining specific additional position information (e.g., for determining the position of the contact point CP). As described above, in various embodiments, the measurement of the workpiece surface is performed by bringing the contact point CP of the end tool ETL into contact with the workpiece surface. In connection with such a measurement, both the position and orientation of the end tool ETL are determined, and correspondingly, the position of the contact point CP may be indicated.

[0029] In various embodiments, different types of end tools ETL can provide different types of outputs that can be utilized in relation to the latch portion 181. For example, in an embodiment where the end tool ETL is a touch probe that is used for measuring a workpiece and outputs a touch signal when contacting the workpiece (e.g., when the contact point CP contacts the workpiece), the latch portion 181 may be configured to input the touch signal or a signal derived therefrom as at least one input signal based on which the timing of the trigger signal is determined. In various embodiments where the end tool ETL is a touch probe, the central axis of the touch probe may correspond to the end tool axis EA. As another example, in an embodiment where the end tool ETL is a scanning probe that is used for measuring a workpiece and provides respective workpiece measurement sample data corresponding to respective sample timing signals, the latch portion 181 may be configured to input the respective sample timing signals or a signal derived therefrom as at least one input signal. As another example, in an embodiment where the end tool ETL is a camera that is used for providing respective workpiece measurement images corresponding to respective workpiece image acquisition signals, the latch portion 181 may be configured to input the workpiece image acquisition signal or a signal derived therefrom as at least one input signal.

[0030] In various embodiments, the measurement system 150 may be configured to determine the position and orientation of the light beam source structure and / or the end tool ETL based on measurement signals from the light beam sensors S1 - S4 of the sensor structure 160. Such a system will be understood to have certain advantages over various alternative systems. For example, in various embodiments, the systems disclosed herein may be smaller and / or less costly and / or more accurate than some alternative systems that utilize alternative techniques (e.g., certain photogrammetry systems, etc.) to track the position and orientation of a moving system. The systems of the present disclosure, unlike alternative systems, do not occupy or block a portion of the operating volume MV, such as by placing scales or fiducial marks on the ground or stage, and do not interfere with the area where the workpiece is processed or inspected (e.g., within the moving volume MV).

[0031] In various embodiments, the comparison between a photogrammetry system and a measurement system 150 as disclosed herein may be described as follows. In a photogrammetry system, a camera may utilize an incoherent light source for imaging the light source to determine position. In some cases, the position and angle may be calculated from the position of the light source. The effective "lever arm" for determining the angle is the distance between the light sources. It is difficult to increase this lever arm. This is because it necessarily also increases the opposing lever arm between the light source and the lower part of the end tool (e.g., corresponding to the distance between the light source and the contact point CP of the end tool along the end tool axis EA direction). In other words, a photogrammetry structure that makes it easier to measure the probe angle also makes the position of the end tool more sensitive to this angle. The field of view of the camera in such a system may cover the entire working volume, which corresponds to a low magnification.

[0032] In contrast, in the measurement system 150 disclosed herein, typically, a coherent light source may be utilized. For example, the light source for the light beam source structure LC may be a coherent light source (e.g., a laser light source), and the light beam may be a coherent light beam (e.g., a laser beam). Diffractive optical elements (e.g., which will be described in more detail below in connection with FIG. 3) may be utilized to generate a plurality of diffracted light beams (e.g., which can be dispersed in a plurality of directions surrounding the light beam source structure LC). In various embodiments, a relatively small percentage of the plurality of diffracted light beams or light beams provided by other means may be directed or otherwise received by the diffused light beam sensor of the measurement system 150 (e.g., to generate a corresponding measurement spot SP on the light beam sensor). In various embodiments, the light beam sensor may be various types of cameras and / or two-dimensional position detection sensors (e.g., a lensless camera, a position-sensitive detector, an optical position sensor capable of measuring the position of a two-dimensional light spot on the sensor surface, etc.). In operation, high-precision azimuth measurement / determination becomes possible (e.g., corresponding to the angle of an end tool, etc.) by a large lever arm (e.g., which partially corresponds to the distance between the light beam source structure LC and the light beam sensor S). In addition, the effective magnification for such operation may be relatively high.

[0033] In various embodiments, the measurement signals from the light beam sensor (e.g., those corresponding to an image and / or indicating the two-dimensional position of the measurement spot SP formed by the light beam, where the centroid of each measurement spot is calculated / determined from the perspective of XYZ coordinates) are utilized in combination with the known characteristics of the light beam source structure LC (e.g., laser projection based on the known geometric relationships of the light beams including the relative three-dimensional angles of each light beam, taking into account the offsets of each light beam at the light source, etc.), and the position and orientation can be calculated / determined (e.g., based on the use of non-linear least squares methods and / or other processing / calculation techniques). In other words, the known vectors of the light beams can be adapted to known positions (e.g., in XYZ coordinates) where they intersect on the light beam sensor (e.g., with respect to the position of the measurement spot SP) to determine the position and orientation of the light beam source structure LC. In various embodiments, the measurement spots SP on the light beam sensor may each be uniquely identified (e.g., by partially utilizing the approximate position information determined by the movement system 110 and / or based on the unique or other distinguishable characteristics of the light beam (e.g., the unique pattern information of the light beam, a pseudo-random pattern having unique or other distinguishable parts, etc.)).

[0034] It will be appreciated that such a combination of features and characteristics of the measurement system 150 may result in a more accurate determination of position and orientation than that provided by a photogrammetry system as described above. As some specific advantages, note that the light beams such as those utilized in the measurement system 150 have corresponding orientation information (e.g., of the light beam source structure LC and the end tool ETL) that is lacking in photogrammetry and are more sensitive to orientation. This can significantly improve the accuracy.

[0035] FIG. 3 is a diagram of a first exemplary embodiment of a light beam source section LP1' of a light beam source structure LC (which may be the same as the light beam source structure LC used in the system of FIG. 1). As shown in FIG. 3, the light beam source section LP1' includes a light source LS1, a reflection element RE1, beam splitters BS1A, BS1B, BS1C, diffractive optical elements DOE1B, DOE1C, and lenses LNS1B1, LNS1B2, LNS1C1, LNS1C2. In various embodiments, the light source LS1 may be a laser source in which at least a part or all of the light beams in the following description may be laser light. The light source LS1 generates a light beam LB1A, which is reflected by the reflection element RE1 and directed towards the beam splitter BS1A. The beam splitter BS1A splits the light beam into light beams LB1B and LB1C, which are respectively directed towards the diffractive optical elements DOE1B and DOE1C.

[0036] The light beam LB1B is diffracted by the diffractive optical element DOE1B into a diffracted light DLB1B, which is split by the beam splitter BS1B into diffracted lights DLB1B1 and DLB1B2. The diffracted light DLB1B1 further diverges after passing through the lens LNS1B1 having an optical axis OA1B1, and the diffracted light DLB1B2 further diverges after passing through the lens LNS1B2 having an optical axis OA1B2. Similarly, the light beam LB1C is diffracted by the diffractive optical element DOE1C into a diffracted light DLB1C, which is split by the beam splitter BS1C into diffracted lights DLB1C1 and DLB1C2. The diffracted light DLB1C1 further diverges after passing through the lens LNS1C1 having an optical axis OA1C1, and the diffracted light DLB1C2 further diverges after passing through the lens LNS1C2 having an optical axis OA1C2.

[0037] Orthogonal X, Y, and Z axes are shown (for example, corresponding to the coordinate system of the light beam source section LP1' and / or the light beam source structure). The optical axes OA1B1 and OA1C1 are shown parallel to the X axis, and the optical axes OA1B2 and OA1C2 are shown parallel to the Y axis.

[0038] In various embodiments, the light beam source unit LP1' may be a first light beam source unit in which the corresponding light beam source structure may include an additional light beam source unit. For example, the light beam source structure may include second and third light beam source units (for example, in some cases, each having a component equal to the first light beam source unit LP1'). In such a configuration, for the second light beam source unit, the optical axes may be parallel to the X-axis and the Z-axis respectively, and for the third light beam source unit, the optical axes may be parallel to the Y-axis and the Z-axis respectively. Therefore, in such a configuration, there may be approximately an equal number of diffracted light beams directed by lenses having optical axes in the X-axis, Y-axis, and Z-axis directions. Such a configuration may result in a relatively uniform distribution of the light beam in the direction from the light beam source structure. In one embodiment, when such a light beam source structure is arranged at the center of a sphere, the intersection points where the light beam intersects the surface of the sphere may be dispersed approximately evenly near the surface of the sphere. In various embodiments, there may be cases where it is desirable for the light beam source structure LC to provide at least a minimum number of light beams dispersed in the directions around the light beam source structure LC (for example, at least 10,000 light beams, or at least 100,000 light beams, etc.). In various embodiments, the desired minimum number of light beams may depend on the light beam source structure LC / light beam sensor distance, the number and size of the light beam sensors, and the range of possible orientations of the light beam source structure LC. In various embodiments, it may be desirable for some or all of the light beams to have similar or approximately equal angular intervals with respect to each other.

[0039] In various embodiments, each of the light beams of the light beam source structure (e.g., each of the diffracted light beams DLB in the example of FIG. 3) may have certain known and / or determined characteristics (e.g., relative angular orientation, light source point of origin, etc.) that spatially associate each light beam with the light beam source structure. Such characteristics can be used to determine the position and orientation of the light beam source structure based at least in part on the light beams directed towards and detected by the light beam sensor of the sensor structure. It should be noted that with respect to the light beam source portion LP1’, the diffracted light beams may have a constant offset relative to each other. For example, the diffracted light beam DLB1B1 may be modeled / evaluated / specified as having a light source point offset along the Y-axis direction (e.g., related to the offset along the Y-axis direction between the lenses LNS1B1 and LNS1C1) from the modeled / evaluated / specified light source point for the diffracted light beam DLB1C1. Such an offset may be included in the position calculation (including the processing / calculation performed by the measurement system position and orientation processing unit 190, for example, to process the measurement signals from the light beam sensor to determine the position and orientation of the light beam source structure LC and / or the end tool ETL, etc.) and / or may be accounted for in other ways. Once the position and orientation of the light beam source structure LC are determined, the known geometric relationship and / or relative position / offset between the light beam source structure LC and the end tool ETL can also be utilized to determine the position and orientation of the end tool ETL. As will be described in more detail below, FIGS. 5A(a) - 5B(h) show specific simplified examples of the light beam B of the light beam source structure LC corresponding to a specific position and orientation of the light beam source structure LC, directed towards the sensor of the sensor structure 160.

[0040] Figures 4(a) and 4(b) are diagrams of respective moving volumes MV-4A and MV-4B surrounded by measurement frame volumes MFV-4A and MFV-4B, at least partially defined by respective sensor structures 160-4A and 160-4B, where each sensor structure includes a different number of optical beam sensors. In each case, the moving volume MV and the measurement frame volume MFV are represented as cubic volumes having edges and sides parallel to the orthogonal X, Y, and Z axis directions. For simplicity of illustration, the volumes and other aspects are shown in specific relative dimensions, but it will be understood that in various embodiments, the relative dimensions of the volumes and other aspects may vary (e.g., the illustrated dimensions may not be to scale, and in that case, the moving volume MV may be larger relative to the measurement frame volume MFV, etc.).

[0041] Figure 4(a) shows an embodiment having a sensor structure 160-4A that includes four optical beam sensors S1 to S4 (e.g., similar to the embodiment shown in FIG. 1 and also relevant to the embodiments of FIGS. 5A(a) to 5(h), as will be described in more detail below). The four optical beam sensors S1 to S4 are arranged to be located at a common intermediate Z height along the Z-axis direction (i.e., all having the same Z-axis coordinate value). The optical beam sensors S1 and S2 are arranged on both sides of the measurement frame volume and are parallel to the YZ plane. The optical beam sensors S3 and S4 are arranged on both sides of the measurement frame volume and are parallel to the XZ plane.

[0042] FIG. 4(b) shows an embodiment having a sensor structure 160-4B that includes 14 optical beam sensors S1A to S1D, S2A to S2D, S3A to S3C, and S4A to S4C. In relation to the sensor structure 160-4A of FIG. 4(a), the sensor structure 160-4B of FIG. 4(b) may have higher measurement resolution and / or higher measurement accuracy in the X-axis direction (e.g., corresponding to the sets of three optical beam sensors S3A to S3C, S4A to S4C arranged at different positions along the X-axis direction on each side of the measurement frame volume MFV-4B). Further, in a further comparison with the sensor structure of FIG. 4(a), the sensor structure 160-4B of FIG. 4(b) may have higher measurement resolution and / or higher measurement accuracy in the Y-axis direction (e.g., corresponding to the sets of two optical beam sensors S1B and S1D, and S2B and S2D arranged at different positions along the Y-axis direction on each side of the measurement frame volume MFV-4B, as compared with the configuration of FIG. 4(a) that uses a single optical beam sensor S1 and S2 on each side). Further, compared with the sensor structure of FIG. 4(a), the sensor structure 160-4B of FIG. 4(b) may also have higher measurement resolution and / or higher measurement accuracy in the Z-axis direction (e.g., corresponding to the sets of two optical beam sensors S1A and S1C, and S2A and S2C arranged at different positions along the Z-axis direction on each side of the measurement frame volume MFV-4B, as compared with the configuration of FIG. 4(a) that uses a single optical beam sensor S1 and S2 on each side).

[0043] Figures 5A(a) through 5B(h) are diagrams showing a light beam source structure LC’ directing four exemplary light beams B1 through B4 at four light beam sensors S1 through S4 of four light beam sensor structures 160’, generating four corresponding measurement spots SP1 through SP4 for different positions and orientations of the light beam source structure LC’. In various embodiments, the sensor structure 160’ may be the same as that of FIGS. 1 and 4(a) (e.g., the four light beam sensors S1 through S4 at least partially define corresponding cubic measurement frame volumes MFV). FIGS. 5A(a) through 5(h) show respective top views 510A through 510H, cross-sectional front views 520A through 520H, cross-sectional side views 530A through 530H, and diagrams 540A through 540H of the positions of the measurement spots (i.e., according to the front views of the respective sensor surfaces of each of the light beam sensors S1 through S4).

[0044] In various embodiments, the examples of FIGS. 5A(a) through 5(h) can also show the operation of sensor structures having a greater number of light beam sensors, and the examples described below can show the operation of four of the total number of light beam sensors in a given configuration (e.g., four of the most central light beam sensors, etc.). The examples of FIGS. 5A(a) through 5B(h) further illustrate the operation of the light beam source structure and can include a greater number of light beams (e.g., 10, 100, or 1000 light beams, etc., which in some cases may be directed in a relatively evenly distributed three-dimensional direction as previously described in connection with FIG. 3). For such embodiments, the examples described below can show the operation of four of the total number of light beams in a given configuration (e.g., four of the most central light beams and / or four light beams specifically directed along the X-axis and Y-axis directions, etc.). Also, with respect to the examples of FIGS. 5A(a) through 5B(h), for the purpose of simplifying the illustrated examples, the relative sizes of the light beam sensors S1 through S4 are exaggerated, the relative distances between the light beam sensors are reduced, and no offset is shown between the light source points of the different light beams B1 through B4.

[0045] In the example of FIG. 5A(a), the light beam source structure LC’ and the corresponding light beams B1 to B4 are shown as being at a designated “null” position (e.g., including the corresponding “null” orientation). More specifically, light beams B1 and B2 are each parallel to the X-axis direction and are each directed towards the centers of light beam sensors S1 and S2, respectively. Similarly, light beams B3 and B4 are parallel to the Y-axis direction and are each directed towards the centers of light beam sensors S3 and S4, respectively. Light beams B1 to B4 generate measurement spots SP1 to SP4 corresponding to the centers of each of light beam sensors S1 to S4, respectively. In various embodiments, light beam sensors S1 to S4 may be various types of cameras and / or two-dimensional position detection sensors (e.g., optical position sensors capable of two-dimensionally measuring the position of a measurement spot formed by a light beam on the sensor surface).

[0046] Light beam sensors S1 to S4 can output measurement signals indicating that measurement spots SP1 to SP4 are at the centers of light beam sensors S1 to S4. Based on the known geometric relationship between light beams B1 to B4 and the light beam source structure LC’, the measurement signals from light beam sensors S1 to S4 indicate the position and orientation of the light beam source structure LC’ (e.g., corresponding to the position and orientation in the example of FIG. 5A(a)). The measurement signals may be processed (e.g., by the processing unit 190), and by this processing, the position and orientation of the light beam source structure LC’ and / or the end tool ETL (e.g., see FIG. 1) to which the light beam source structure LC’ is coupled may be determined.

[0047] In the example of Fig. 5A(b) (for example, when compared with the example of Fig. 5A(a)), the light beam source structure LC’ is shown as rotating clockwise in the XY plane. The top view 510B (i.e., of the XY plane) shows the clockwise rotation and the different positions of the light beams B1 - B4 on the light beam sensors S1 - S4. The diagram 540B of the positions of the measurement spots shows the positions SP1 - SP4 of the measurement spots on the light beam sensors S1 - S4 respectively generated by the light beams B1 - B4. More specifically, the measurement spots SP1 - SP4 are shown as having moved to the right of the centers of the respective light beam sensors S1 - S4.

[0048] In the example of Fig. 5A(c) (for example, when compared with the example of Fig. 5A(a)), the light beam source structure LC’ is shown as rotating clockwise in the XZ plane. The cross-sectional front view 520C (i.e., of the XZ plane) shows the clockwise rotation and the different positions of the light beams B1 and B2 on the light beam sensors S1 and S2. In the diagram 540C of the positions of the measurement spots, the measurement spots SP1 and SP2 are shown as having moved to the upper center and lower center of the respective light beam sensors S1 and S2, and the measurement spots SP3 and SP4 are shown as remaining at the centers of the respective light beam sensors S3 and S4.

[0049] In the example of Fig. 5A(d) (for example, when compared with the example of Fig. 5A(a)), the light beam source structure LC’ is shown as rotating clockwise in the YZ plane. The cross-sectional side view 530D (i.e., of the YZ plane) shows the clockwise rotation and the different positions of the light beams B3 and B4 on the light beam sensors S3 and S4. In the diagram 540D of the positions of the measurement spots, the measurement spots SP1 and SP2 are shown as remaining at the centers of the respective light beam sensors S1 and S2, while the measurement spots SP3 and SP4 are shown as having moved to the upper center and lower center of the respective light beam sensors S3 and S4.

[0050] Note that the examples of FIGS. 5A(b) to 5A(d) each correspond at least to a change in the orientation of the light beam source structure LC'. In some embodiments, the illustrated changes may not necessarily correspond to a change in position (for example, depending on where the reference point of the light beam source structure LC' is specified, the change in position is determined in relation to that reference point). In the examples of FIGS. 5A(a) to 5B(h), in various embodiments, the reference point of the light beam source structure may be specified as being located at the geometric center of the light beam source structure, or at another center.

[0051] In the example of FIG. 5B(e) (for example, when compared with the example of FIG. 5A(a)), the light beam source structure LC' is shown as having moved in the XY plane towards the light beam sensor S4. The top view 510E (i.e., of the XY plane) shows different positions of the light beams B1 and B2 on the light beam sensors S1 and S2. In the view 540E of the positions of the measurement spots, the measurement spots SP1 and SP2 are shown as having moved to the center right and center left, respectively, of the light beam sensors S1 and S2, and the measurement spots SP3 and SP4 remain at the centers of the light beam sensors S3 and S4, respectively.

[0052] In the example of FIG. 5B(f) (for example, when compared with the example of FIG. 5A(a)), the light beam source structure LC' is shown as having moved in the XY plane towards the light beam sensor S1. The top view 510F (i.e., of the XY plane) shows different positions of the light beams B3 and B4 on the light beam sensors S3 and S4. In the view 540F of the positions of the measurement spots, the measurement spots SP1 and SP2 remain at the centers of the light beam sensors S1 and S2, respectively, but the measurement spots SP3 and SP4 are shown as having moved to the center right and center left, respectively, of the light beam sensors S3 and S4.

[0053] In the example of FIG. 5B(g), the light beam source structure LC’ is shown as being moved upward in the Z direction (i.e., parallel to the Z axis) (for example, when compared with the example of FIG. 5A(a)). Cross-sectional front view 520G and cross-sectional side view 530G (i.e., the XZ plane and the YZ plane respectively) show the different positions of the light beams B1 and B2 on the light beam sensors S1 and S2, and the different positions of the light beams B3 and B4 on the light beam sensors S3 and S4, respectively. In FIG. 540G of the positions of the measurement spots, the measurement spots SP1 to SP4 are shown as having moved to the upper part of the centers of the light beam sensors S1 to S4, respectively.

[0054] In the example of FIG. 5B(h) (for example, when compared with the example of FIG. 5A(a)), the light beam source structure LC’ is shown as having been rotated clockwise in the XY plane and moved upward in the Z direction (i.e., parallel to the Z axis). Top view 510H (i.e., of the XY plane) shows the clockwise rotation and the different positions of the light beams B1 to B4 on the light beam sensors S1 to S4. Cross-sectional front view 520H and cross-sectional side view 530H (i.e., the XZ plane and the YZ plane respectively) show the different positions of the light beams B1 and B2 on the light beam sensors S1 and S2, and the different positions of the light beams B3 and B4 on the light beam sensors S3 and S4, respectively. In FIG. 540H of the positions of the measurement spots, the measurement spots SP1 to SP4 are shown as having moved the light beam sensors S1 to S4 to the upper right corner respectively.

[0055] As described above, the optical beam sensors S1 to S4 can output measurement signals indicating the positions of the respective measurement spots SP1 to SP4 on the respective optical beam sensors S1 to S4. Based on the known geometric relationships between the optical beams B1 to B4 and the optical beam source structure LC' (including, for example, directing the known angular orientations of the optical beams B1 to B4 by, in relation to, and in relation to each other by the optical beam source structure LC'), the positions of the measurement spots SP1 to SP4 on the optical beam sensors S1 to S4 indicate the position and orientation of the optical beam source structure LC' (corresponding to the orientation in the examples of FIGS. 5A(a) to 5B(h), for example). The measurement signals from the optical beam sensors S1 to S4 may be processed (by, for example, the processing unit 190), and by this processing, the position and orientation of the optical beam source structure LC' and / or the end tool ETL (see FIG. 1, for example) to which the optical beam source structure LC' is coupled may be determined (utilizing at least partially, for example, known geometric relationships, etc.).

[0056] Regarding the measurement signals from the optical beam sensors S1 to S4 indicating the position and orientation of the optical beam source structure LC', it is understood that all of the simplified examples of FIGS. 5A(a) to 5B(h) illustrate the case where the optical beams B1 to B4 are respectively directed towards the corresponding optical beam sensors S1 to S4. More specifically, in each example, the optical beam B1 is directed towards the optical beam sensor S1, the optical beam B2 is directed towards the optical beam sensor S2, the optical beam B3 is directed towards the optical beam sensor S3, and the optical beam B4 is directed towards the optical beam sensor S4. In these examples, when the optical beam source structure LC' is rotated by 90 degrees, 180 degrees, or 270 degrees within the XY plane, similar measurement spots may be generated at similar positions on the optical beam sensors S1 to S4, and it may be desirable to eliminate (e.g., distinguish) the ambiguity regarding such a possibility.

[0057] For example, with respect to the orientation shown in FIG. 5A(a), when the light beams B1 to B4 are directed toward the respective light beam sensors S1 to S4, the measurement signals indicating that the respective measurement spots SP1 to SP4 are at the centers of the respective light beam sensors S1 to S4 will uniquely indicate that the light beam source structure LC’ is at the position and orientation illustrated in FIGS. 510A to 530A of FIG. 5A(a) (e.g., corresponding to the “null position” in a given embodiment). However, with respect to the top view 510A, when rotated 90 degrees clockwise within the XY plane, the measurement spots SP are similarly generated at the centers of the light beam sensors S1 to S4. More specifically, the light beam B1 generates the measurement spot SP1 at the center of the light beam sensor S4, the light beam B2 generates the measurement spot SP2 at the center of the light beam sensor S3, the light beam B3 generates the measurement spot SP3 at the center of the light beam sensor S1, and the light beam B4 generates the measurement spot SP4 at the center of the light beam sensor S2. It will be understood that similar measurement spots at the centers of the light beam sensors S1 to S4 generated by the respective different measurement beams may occur when the configuration is rotated 180 degrees and 270 degrees in the same clockwise direction within the XY plane with respect to the initial orientation shown in the top view 510A.

[0058] To eliminate the ambiguity between sets of measurement signals resulting from such orientations (e.g., otherwise they might appear relatively identical), it may be desirable for the system to be configured to determine (e.g., at least approximately) which optical beam is generally directed at which optical beam sensor. As one way to address such problems, position information from the mobile system 110 can be utilized to eliminate the ambiguity. For example, in connection with the measurement system 110 described above with respect to FIGS. 1 and 2, position information determined from position sensors SEN1 to SEN5 (e.g., such as received by the mobile system position and orientation processor 147) can be used to determine the approximate position and orientation of the end tool ETL and / or the optical beam source structure LC (e.g., with the mobile system accuracy). Although the mobile system accuracy may be lower than that desired for a particular application, it may be useful for eliminating the ambiguity (e.g., as described in connection with the above example). More specifically, the accuracy of the mobile system can provide approximate position information (e.g., information indicating the approximate position and direction of the end tool ETL and / or the optical beam source structure LC), and this can be used to identify which optical beam is generally directed at which optical beam sensor.

[0059] Returning to the above example, in the example of the configuration of FIG. 5A(a) where the measurement signals from the optical beam sensors S1 to S4 indicate that all the measurement spots are at the center of the optical beam sensor, the ambiguity of the possible orientations of the optical beam source structure LC’ (e.g., whether it is a 0-degree rotation, a 90-degree rotation, a 180-degree rotation, or a 270-degree rotation as shown in FIG. 5A(a)) can be eliminated by using the position and orientation information from the movement system. For example, using the position and orientation information from the movement system 110, it is possible to determine whether the measurement spot at the center of the optical beam sensor S1 is generated by the optical beams B1, B2, B3, or B4. As described above, even when the measurement system accuracy is relatively low, it can be effectively utilized by the measurement system to eliminate the above-mentioned ambiguity of possibilities (according to the approximate position information provided by the movement system), and the measurement system can effectively provide higher-precision measurements according to the process as described herein.

[0060] In various embodiments, the general characteristics of the relationship between the measurement signals of the movement system 110 and the measurement signals of the measurement system 150 can be described as follows. The position and orientation information (e.g., including measurement values) determined from one or more of the position sensors SEN1 to SEN5 of the movement system 110 (i.e., with the accuracy of the movement system) may be characterized by providing information on a relatively large scale (e.g., including approximate scale measurements of position and orientation). The position and orientation information (e.g., including measurement values) determined from the measurement system 150 (e.g., based on the measurement signals from the optical beam sensors) may be characterized by providing information on a relatively fine scale (e.g., including fine scale measurements of position and orientation). In various embodiments, it is possible to combine the measurement values of the two systems to provide high-precision measurement values within a relatively large non-ambiguous range (e.g., micron-level accuracy over a cubic meter of moving volume, etc.).

[0061] As a specific example, in one exemplary embodiment, the positioning accuracy / potential position error of the movement system is approximately on the order of 100 microns (e.g., when provided as a rough scale range in a movement / measurement space of 1 cubic meter as an ambiguity range). In this example, the measurement system may be configured to resolve potential distance errors in rough scale measurements, such as having an ambiguity range larger than the potential distance error (e.g., in this example having an ambiguity range exceeding 100 microns and having a fine scale range of micron-level accuracy). According to such exemplary values, the measured values (e.g., position and orientation information) of the two systems can be combined to provide a high-precision measured value (e.g., micron-level accuracy in a moving volume of 1 cubic meter).

[0062] Regarding a measurement system as disclosed herein, such a principle can also be generally explained from the perspective of identifying / eliminating ambiguity as to which light beam of the light beam source structure is directed at which light beam sensor (e.g., for a given measurement spot on a light beam sensor). Regarding the above exemplary values, the positioning accuracy / potential position error of approximately 100 microns of the movement system (e.g., the ambiguity range provided in a movement / measurement volume of 1 cubic meter as a rough scale range) may be sufficient to identify / determine / eliminate ambiguity as to which light beam is directed at which light beam sensor. The ambiguity range of the measurement system (e.g., in the above example a range exceeding 100 microns and having micron-level accuracy as a fine scale range) may correspond to a range in which different positions and orientations of the light beam source structure can be clearly determined (e.g., as partially shown by the simplified examples of FIGS. 5A(a) - 5B(h) according to when the measurement spot moves on the light beam sensor or exists at different respective positions).

[0063] As an alternative to and / or in addition to the above embodiments (e.g., the position information from the movement system is utilized for ambiguity elimination), the light beam may also have certain characteristics that can be utilized for ambiguity elimination (e.g., enabling the determination of which light beam is directed at which light beam sensor). For example, the light beam may be arranged in a pattern (e.g., having unique portions). In various embodiments, the light beam may, in addition or as an alternative, have different wavelengths (e.g., colors), timings, modulations, structures, and / or other characteristics, and those characteristics may be detected / identified and utilized to specify which light beam is directed at which light beam sensor (e.g., when the light beam sensor includes different color detectors and has corresponding identification capabilities). In various embodiments, one or more characteristics of the light beam (e.g., timing, modulation, etc.) may be controlled by the light beam source structure control unit 192 (e.g., see FIG. 2), and this light beam source structure control unit 192 can provide relevant signals (e.g., timing signals, etc.) to the sensor structure control processing unit 180 and / or the measurement system orientation processing unit 190 (e.g., for use as part of the process of receiving measurement signals from the light beam sensor and using those measurement signals to determine which light beam is directed at which light beam sensor).

[0064] Figures 6(a) to 6(c) are diagrams showing i) twelve exemplary light beams B of the light beam source structure LC'', and ii) the corresponding measurement spots SP on four sensors S1 to S4 of the sensor structure 160'' at different positions and orientations of the light beam source structure LC''. More specifically, in various embodiments, the light beam source structure LC'' provides and directs light beams B1, B2A to B2C, B3A to B3C, and B4A to B4E to form corresponding measurement spots SP1, SP2A to SP2C, SP3A to SP3C, and SP4A to SP4E on the light beam sensors S1 to S4. In the examples of FIGS. 6(a) to 6(c), the light beams are arranged in a pattern (e.g., in the orientation of FIG. 6(a), i) a single light beam B1 is directed towards the light beam sensor S1, ii) three light beams B2A to B2C are directed towards the light beam sensor S2, iii) three light beams B3A to B3C are directed towards the light beam sensor S3, iv) five light beams B4A to B4E are directed towards the light beam sensor S4). Such patterns may include the spacing and orientation (e.g., angular spacing and orientation) between the light beams and / or other characteristics, which can uniquely identify a part of the pattern directed towards the light beam sensor or group of light beam sensors (e.g., for use in determining the orientation and / or position of the light beam sensor structure and / or eliminating ambiguity).

[0065] In the example of FIG. 6(a) (which has a certain similarity to the orientation shown in FIG. 5A(a)), the light beam source structure LC'', and the corresponding light beams B1, B2A to B2C, B3A to B3C and B4A to B4E are shown as being at a designated "null" position (e.g., including the corresponding "null" orientation). More specifically, the light beam B1 and the central light beam B2B are each parallel to the X-axis direction and are each directed towards the center of the light beam sensors S1 and S2 respectively. Similarly, the central light beams B3B, B4C are parallel to the Y-axis direction and are each directed towards the center of the light beam sensors S3, S4 respectively.

[0066] In the orientation shown in FIG. 6(a), the light beams B1, B2A to B2C, B3A to B3C, and B4A to B4E generate corresponding measurement spots SP1, SP2A to SP2C, SP3A to SP3C, and SP4A to SP4E on the light beam sensors S1 to S4, respectively. As shown in FIG. 640A of the positions of the measurement spots, the measurement spots SP1, SP2B, SP3B, and SP4C are all at the respective centers of the light beam sensors S1, S2, S3, and S4. It should be noted that these measurement spot positions are the same as the measurement spot positions shown in FIG. 5A(a). However, unlike FIG. 5A(a) where only a single measurement spot is generated on each light beam sensor, in FIG. 6(a), depending on the pattern of the light beams supplied and directed by the light beam source structure LC'', different numbers and / or arrays of measurement spots are formed on different light beam sensors.

[0067] For example, the light beam B1 generates only a single measurement spot SP1 at the center of the light beam sensor S1, while the light beams B2A to B2C and B3A to B3C generate a row of three measurement spots SP2A to SP2C and SP3A to SP3C, respectively, crossing the centers of the light beam sensors S2 and S3. Further, the light beams B4A to B4E generate a row of five measurement spots SP4A to SP4E crossing the center of the light beam sensor S4. Such characteristics enable the determination of which light beam is directed at which light beam sensor (e.g., to eliminate ambiguity regarding the above-mentioned problems), and it may be possible that no additional position information (e.g., from a moving system) is required (although in some embodiments, it may be used in combination with such patterns or other information).

[0068] The optical beam sensors S1 to S4 can output measurement signals indicating that the measurement spots SP1, SP2A to SP2C, SP3A to SP3C, and SP4A to SP4E are at the positions shown on the optical beam sensors S1 to S4. Based on the known geometric relationships between the optical beams B1, B2A to B2C, B3A to B3C, and B4A to B4E and the optical beam source structure LC'', the measurement signals from the optical beam sensors S1 to S4 indicate the position and orientation of the optical beam source structure LC''. The measurement signals may be processed (e.g., by the processing unit 190), and based on this processing, the position and orientation of the optical beam source structure LC'' and / or the end tool ETL (e.g., see FIG. 1) to which the optical beam source structure LC'' is coupled may be determined.

[0069] In the example of FIG. 6(b) (e.g., compared with the example of FIG. 6(a)), the optical beam source structure LC'' is shown as being rotated clockwise in the XY plane and moved upward in the Z direction (i.e., parallel to the Z axis and having some similarities with the example of FIG. 5B(h)). The top view 610B (i.e., of the XY plane) shows the clockwise rotation and top view of the different positions of the optical beams B1, B2A to B2B, B3A to B3B, and B4A to B4C on the optical beam sensors S1 to S4. Note that the optical beams B2C, B3C, and B4D to B4E are no longer directed towards their respective optical beam sensors but instead are directed towards the spaces between the optical beam sensors of the sensor structure (such optical beams may typically occur for a relatively evenly distributed optical beam pattern of a limited number of optical beams having a limited size and being at a relatively large distance from the optical beam source structure and directed towards a relatively limited number of optical beam sensors). The cross-sectional views 620B and 630B (i.e., in the cross-sectional XZ plane and YZ plane, respectively) show the different positions of the optical beams B1 and B2A on the optical beam sensors S1 and S2 and the different positions of the optical beams B3A and B4A on the optical beam sensors S3 and S4, respectively.

[0070] In FIG. 640B of the measurement spot positions, the measurement spots SP1, SP2A to SP2B, SP3A to SP3B, and SP4A to SP4C are each shown as having moved upward and then rightward on the light beam sensors S1 to S4, respectively. Also, in FIG. 640B of the measurement spot positions, it should be noted that (i.e., due to the corresponding light beams B2C, B3C, and B4D to B4E being directed into the space between the light beam sensors), the measurement spots SP2C, SP3C, and SP4D to SP4E formed on the light beam sensors S2 to S4 disappear. This example partially shows the reason why it may be desirable to have a sufficient number and / or relatively even distribution of light beams emitted in a direction (or directions) from the light beam source structure. More specifically, in a given embodiment, based on the size of the light beam sensor (e.g., during a measurement operation) and the possible distance from the light beam source structure, generally, it may be desirable for the light beam source structure to provide a sufficient number and density of light beams in the direction surrounding the light beam source structure. Such factors regarding the light beam source structure can help ensure that at least some of the light beams are directed (e.g., for all possible orientations of the light beam source structure during a measurement operation) to generate corresponding measurement spots and corresponding measurement signals for at least one or all of the light beam sensors of the sensor structure.

[0071] In the example of FIG. 6(c) (for example, as compared with the example of FIG. 6(a)), the light beam source structure LC’’ is shown as being completely rotated 90 degrees clockwise in the XY plane. The top view 610C (i.e., of the XY plane) shows a 90-degree clockwise rotation and the top views of the different positions of the light beams B1, B2A - B2C, B3A - B3C, and B4A - B4E. Due to the 90-degree rotation, the light beam B1 is shown as being directed towards the light beam sensor S4 (instead of the light beam sensor S1 as in the orientation of FIG. 5A(a) for example). The light beams B2A - B2C are shown as being directed towards the light beam sensor S3 (instead of the light beam sensor S2 as in the orientation of FIG. 5A(a) for example). The light beams B3A - B3C are shown as being directed towards the light beam sensor S1 (instead of the light beam sensor S3 as in the orientation of FIG. 5A(a) for example). The light beams B4A - B4E are shown as being directed towards the light beam sensor S2 (instead of the light beam sensor S4 as in the orientation of FIG. 5A(a) for example). The light beam B1 and the central light beam B2B are each parallel to the Y-axis direction and are respectively directed towards the centers of the light beam sensors S4 and S3. Similarly, the central light beams B3B, B4C are each parallel to the X-axis direction and are respectively directed towards the centers of the light beam sensors S1, S2.

[0072] In the orientation shown in FIG. 6(c), the light beams B1, B2A - B2C, B3A - B3C, and B4A - B4E generate corresponding measurement spots SP1, SP2A - SP2C, SP3A - SP3C, and SP4A - SP4E on the light beam sensors S4, S3, S1, and S2 respectively. As shown in FIG. 640C of the positions of the measurement spots, the measurement spots SP1, SP2B, SP3B, and SP4C are all at the respective centers of the light beam sensors S4, S3, S1, and S2. Different from FIGS. 5A(a) - 5B(h) where only a single measurement spot is generated on each light beam sensor as described above, in FIG. 6(c), different numbers of measurement spots are provided by the light beam source structure LC’’ and are formed on different light beam sensors according to the pattern of the light beams directed.

[0073] For example, the light beam B1 generates only a single measurement spot SP1 at the center of the light beam sensor S4, while the light beams B2A to B2C and B3A to B3C generate, respectively, a row of three measurement spots SP2A to SP2C and SP3A to SP3C that cross the center of the light beam sensors S3 and S1. Further, the light beams B4A to B4E generate a row of five measurement spots SP4A to SP4E that cross the center of the light beam sensor S2. With such characteristics, it will be understood that it becomes possible to determine which light beam is directed at which light beam sensor (for example, it is possible to eliminate ambiguity regarding problems as described above).

[0074] For example, the measurement signal from the light beam sensor S4 indicates the position of a single measurement spot SP1 at the center of the light beam sensor S4 as uniquely corresponding to the light beam B1 (for example, in comparison with the orientation of FIG. 6(a) in which the measurement signal from the light beam sensor S1 uniquely indicates the light beam B1 directed at the light beam sensor S1). The measurement signal from the light beam sensor S4 indicates the positions of the measurement spots SP4A to SP4E in the central row of the light beam sensor S4 as uniquely corresponding to the light beams B4A to B4E (for example, in comparison with the orientation of FIG. 6(a) in which the measurement signal from the light beam sensor S4 uniquely indicates the light beams B4A to B4E directed at the light beam sensor S4). Depending on the pattern of the light beam from the light beam source structure LC’’ having a unique pattern portion or a pattern portion distinguished by other means, corresponding unique pattern portion measurement spots may be formed on each light beam sensor to which the pattern portion is directed. With such a configuration, it becomes possible to specify which light beam is directed at which light beam sensor using the measurement signal from the light beam sensor (for example, for eliminating ambiguity and / or determining the position and orientation of the light beam source structure LC’’ with respect to the light beam sensors S1 to S4).

[0075] Figures 7(a) and 7(b) are diagrams showing a first arrangement of measurement spots SP formed by light beams from a light beam source structure at first and second distances from a light beam sensor S1, respectively. In the example of FIG. 7(a), the light beam source structure is at a first distance, which is a relatively short distance (e.g., 10 cm) from the light beam sensor S1. The light beam source structure emits a pattern of light beams having an angular spacing / angular dispersion such that a number of measurement spots SP are generated on the light beam sensor S1 at the relatively short distance of FIG. 7(a). In contrast, in the example of FIG. 7(b), the light beam source structure is at a second distance, which is a relatively long distance (e.g., 60 cm) from the light beam sensor S1. As a result of the longer distance and angular spacing / angular dispersion of the light beam, fewer measurement spots are generated on the light beam sensor S1. Further, each of the corresponding measurement spots SP in FIG. 7(b) is larger than in FIG. 7(a) (e.g., based on additional divergence of the light beam over the longer distance to the sensor S1 in FIG. 7(b)).

[0076] Figures 8(a) and 8(b) are diagrams showing a second arrangement of measurement spots SP formed by light beams from a light beam source structure at first and second distances from a light beam sensor S1, respectively. FIGS. 8(a) and 8(b) show examples similar to those of FIGS. 7(a) and 7(b), except that the light beams and corresponding patterns are more structured. For example, the light beams are arranged such that the measurement spots are generated in evenly spaced rows and columns, the light beams are more collimated, or other structures are applied to generate larger-sized measurement spots at short distances and suppress size variations at different distances. In some embodiments, when the distances between some light sources and light source structures and the light beam sensor vary over a wide range, it may generally be desirable to use more parallelized beams, such as in the examples of FIGS. 8(a) and 8(b). As shown in FIG. 8(a), the measurement spots SP are generated in rows and columns that are relatively evenly spaced on the light beam sensor S1, and their areas are shown as relatively similar large areas compared to FIG. 8(b).

[0077] In the example of FIG. 8(a), the light beam source structure is at a first distance that is a relatively short distance from the light beam sensor S1 (e.g., 500 mm). The light beam source structure emits a pattern of light beams having an angular spacing / angular dispersion such that a large number of measurement spots SP are generated on the light beam sensor S1 at the relatively short distance of FIG. 8(a). In the example of FIG. 8(b), the light beam source structure is at a second distance that is a relatively long distance from the light beam sensor S1 (e.g., 1500 mm). As a result of the longer distance and the angular spacing / angular dispersion of the light beam in FIG. 8(b), fewer measurement spots are generated on the light beam sensor S1. In the examples of FIGS. 8(a) and 8(b), the light beam sensor S1 includes an array of pixels (e.g., an array of 3600 pixels×5400 pixels).

[0078] As a general requirement for the operation of the measurement system 100, it is desirable to have at least one measurement spot generated on each light beam sensor (e.g., with respect to at least a part of the light beam sensor). In addition, it is also desirable that there are not too many measurement spots generated on each light beam sensor (e.g., there is a possibility that the accuracy of the measurement spot position decreases due to the measurement spots overlapping, or it becomes difficult for the system to identify which light beam generated the measurement spot). FIG. 8(a) is an example that may be characterized, in particular in one embodiment, by having more measurement spots on the light beam sensor S1 than the desired number (e.g., with such a high density of measurement spots, it is possible to see how the measurement spots start to overlap).

[0079] Regarding FIGS. 7(b) and 8(b), it will be understood that as the distance from the sensor S1 to the light beam source structure increases, the density of the measurement spots on the light beam sensor S1 significantly decreases, and correspondingly, the interval between the measurement spots increases. In the case where the density between the measurement spots in FIGS. 7(b) and 8(b) is low and the interval is large, when the light beam source structure moves further away from the sensor S1, the interval between the measurement spots generated at such a distance becomes very wide, and there is a possibility that the sensor S1 may fit within these intervals. In this case, it will be understood that depending on the specific position and orientation of the light beam source structure, measurement spots may not be generated on the light beam sensor S1.

[0080] As will be described in detail below, it may generally be desirable for the light beam source structure to i) have a relatively low density of measurement spots at a short working distance (i.e., when the light beam source structure is relatively close to the light beam sensor so that excessive measurement spots are not generated on the light beam sensor), and ii) have a relatively high density of measurement spots at a long working distance (i.e., when the light beam source structure is relatively far from the light beam sensor so that at least one or more measurement spots are generated on each light beam sensor). As will be described in more detail below, according to the principles described herein, such problems can be addressed by a configuration in which the light beam source structure provides both a first pattern of light beams with a lower density of light beams and a second pattern of light beams with a higher density of light beams.

[0081] FIGS. 9(a) and 9(b) are diagrams showing a light beam source structure LC that is at a first distance D1 and a second distance D2 from the light beam sensor S1, respectively, and provides a first pattern BP1 of light beams. As shown in FIGS. 9(a) and 9(b), the light beam source structure LC provides a first pattern BP1 of light beams having a first pattern light beam BP1LB with a relatively low density. As a result, as shown in FIG. 9(a), when the light beam source structure LC is at a distance D1 (e.g., a relatively short distance) from the light beam sensor S1, measurement spots with a relatively low density are generated.

[0082] In the simplified examples of FIGS. 9(a) and 9(b), the density of the first pattern light beam BP1LB can be referenced by the number of light beams included within a specific angular range, for example, referenced based on angle A1. In one specific numerical example, angle A1 is about 30 degrees. In the two-dimensional view of FIGS. 9(a) and 9(b), since the first pattern light beam BP1LB is shown at an angular interval of about 15 degrees, three first pattern light beams BP1LB are illustrated within the 30-degree range of angle A1. In the example of FIG. 9(a), it is shown that the three illustrated first pattern light beams BP1LB generate three corresponding measurement spots on the light beam sensor S1.

[0083] In the example of FIG. 9(b), the light beam source structure LC is shown as being at a distance D2 (for example, a relatively long distance) from the light beam sensor S1. Considering the angular interval / angle density of the first pattern light beam BP1LB, it can be seen that at the longer distance D2, only one first pattern light beam BP1LB is directed towards the light beam sensor S1, generating a corresponding measurement spot. It is also shown that at the distance D2, the linear interval between the first pattern light beams BP1LB is D3. As shown in the illustration, since the distance D3 is larger than the corresponding dimension of the light beam sensor S1, the light beam sensor S1 can accommodate the first pattern light beams BP1LB (i.e., separated by the interval D3 at the distance D2). As an example, the position of the light beam sensor S1' (i.e., the distance D2) where it enters between the first pattern light beams BP1LB is shown. As a result, the first pattern light beams BP1LB are not directed towards the light beam sensor S1', and the corresponding measurement spots are not generated on the light beam sensor S1'.

[0084] As described above, in various embodiments, for the measurement system to accurately determine the position and orientation of the light beam source structure LC, at least a portion of the light beam sensors of the sensor structure must receive the light beam and corresponding measurement spots must be generated. In this regard, the fact that the light beam pattern has an angular spacing / angular dispersion may result in a non-desired number of measurement spots being generated on the light beam sensors at a particular position and orientation, which is generally considered undesirable. In connection with such considerations, FIG. 9(a) shows that the first pattern BP1 of the light beam generates a desired number of measurement spots on the light beam sensor S1 at a distance D1, but as shown in FIG. 9(b), at a distance D2, note that there is an angular spacing / angular dispersion such that less than the desired number of measurement spots are generated on the corresponding light beam sensors (e.g., no measurement spots are generated on the light beam sensor S1’).

[0085] FIGS. 10(a) and 10(b) are diagrams showing a light beam source structure LC that is at a first distance D1 and a second distance D2, respectively, from a light beam sensor S1 and provides a second pattern BP2 of the light beam. As shown in FIGS. 10(a) and 10(b), the second pattern BP2 of the light beam has a higher density of second pattern light beams BP2LB (e.g., compared to the first pattern BP1 of the light beam with the relatively low density first pattern light beams BP1LB of FIGS. 9(a) and 9(b)). In the examples of FIGS. 10(a) and 10(b), the angle A1 is referenced as being about 30 degrees and the second pattern light beams BP2LB are shown as having an angular spacing of about 2.5 degrees, and thus, in the two-dimensional diagrams of FIGS. 10(a) and 10(b), 13 second pattern light beams BP2LB are shown for a 30-degree range of the angle A1. These exemplary numbers of light beams were chosen for illustrative purposes and it is understood that in a particular embodiment, the number of light beams generated by the light beam source structure (e.g., in a typical embodiment) may be much larger (e.g., over 10,000 light beams).

[0086] As shown in Fig. 10(a), the light beam source structure LC is at a distance D2 from the sensor S1. At the distance D2, in a state where there is an angular interval / angle dispersion corresponding to the second pattern light beam BP2LB with a high density, it is shown that three of the second pattern light beams BP2LB are directed towards the sensor S1, and correspondingly, three measurement spots are generated on the sensor S1 (for example, in this case, it can be considered as an example of a desirable number of measurement spots). As shown in Fig. 10(b), the light beam source structure LC is at a distance D1 from the light beam sensor S1, and considering the angular interval / angle dispersion of the second pattern light beam BP2LB, it is shown that 13 second pattern light beams BP2LB are directed towards the light beam sensor S1, and correspondingly, 13 measurement spots are formed on the light beam sensor S1. In one particular embodiment, this may be regarded as an example where there are too many measurement spots formed on the light beam sensor S1 (for example, the measurement spots may overlap, and / or it may become difficult for the measurement system to determine / distinguish the measurement spots and the corresponding light beams, and / or it may cause other processing problems, etc.).

[0087] As a comparison between FIGS. 9(a) - 9(b) and FIGS. 10(a) - 10(b), as shown in FIG. 9(a), it should be noted that when the light beam source structure LC is at a distance D1 from the light beam sensor S1, the first pattern BP1 of the light beam may generate a desirable number of measurement spots on the sensor S1. Also, as shown in FIG. 10(a), when the light beam source structure LC is at a distance D2 from the sensor S1, it should be noted that the second pattern BP2 of the light beam may generate a desirable number of measurement spots on the sensor S1. As will be described in more detail below, in accordance with the principles described herein, in various embodiments, a light beam source structure LC is provided and configured to direct both the first pattern BP1 and the second pattern BP2 of the light beam towards the light beam sensor of the sensor structure 160, and may be configured to indicate the position and orientation of the light beam source structure LC.

[0088] Figures 11A and 11B are diagrams showing a light beam source structure LC that is at a first and second distance from first and second light beam sensors S1 and S2 and provides first and second patterns BP1 and BP2 of light beams. As shown in FIG. 11A, the light beam source structure LC is at a distance D1 from the light beam sensor S1 and at a distance D2 from the light beam sensor S2. This example is said to be similar to the examples of FIGS. 1 and 5B(f), and the light beam source structure LC is shown to be relatively close to the light beam sensor S1 and relatively far from the light beam sensor S2 (for example, the configurations and techniques described below may be utilized).

[0089] In the example of FIG. 11A, the first pattern BP1 of the light beam forms a desired number of measurement spots (e.g., three measurement spots) on the light beam sensor S1 (e.g., similar to the example of FIG. 9(a)), and the second pattern BP2 of the light beam forms a desired number of measurement spots (e.g., three measurement spots) on the light beam sensor S2 (e.g., similar to the example of FIG. 10(a)). According to the principles described herein, the first pattern light beam BP1LB and the second pattern light beam BP2LB have at least one different characteristic that can distinguish the first pattern light beam BP1LB from the second pattern light beam BP2LB. As some examples, in various embodiments, the at least one different characteristic may include different wavelengths, different polarizations, different transmission timings, etc.

[0090] In various embodiments, the measurement system includes one or more optical beam selectors configured to operate based on at least one different characteristic. For example, in various embodiments, as will be described in more detail below, one or more selectors may include one or more optical beam filtering portions (e.g., as shown in the examples of FIGS. 11A and 11B, such as optical beam filtering portions F1 and F2 described in more detail below, an optical beam filtering portion may be disposed in front of each optical beam sensor). In various embodiments, the optical beam selector of the system may include a processing unit 190 or a part of another processing portion that selects, filters, and / or blocks signals generated by the optical beam, and its operation may be based on at least one different characteristic of the optical beam (e.g., based on at least one of different wavelengths, different polarizations, differences in transmission timing, etc.).

[0091] As will be described in more detail below, in various embodiments, the optical beam filtering portions F1 and F2 can be included so as to be disposed in front of the optical beam sensors S1 and S2, respectively. In various embodiments, the optical beam filtering portions F1 and F2 (in some embodiments, including an electric filter wheel configured to be electronically controlled to rotate or move in front of each sensor, or having other configurations) may include at least one of a wavelength filter or a polarization filter. In the example of FIG. 11A, when the optical beam source structure LC is at a position at a distance D1 from the optical beam sensor S1, the optical beam filtering portion F1 may include a filter disposed in front of the optical beam sensor S1 (e.g., utilized by rotation, movement, or other means) to block or filter the second pattern optical beam BP2LB. In this way, the optical beam sensor S1 can be made to generate and / or provide a measurement signal only based on the measurement spot (corresponding to the desired number of measurement spots described in FIG. 9(a)) generated by the first pattern optical beam BP1LB.

[0092] In various embodiments, the optical beam filtering unit F1 may be utilized (e.g., moved in front of the optical beam sensor S1 or otherwise utilized) based on a determined position of the optical beam source structure LC (e.g., as corresponding to the distance D1 from the optical beam source structure LC of the optical beam sensor S1). For example, the motion control system 140 of the mobile system 110 may be configured to provide position information (e.g., with mobile system accuracy) indicating that the optical beam source structure LC is at a distance D1 from the optical beam sensor S1. Based at least in part on the distance indicated by the position information from the motion control system 140, the filtering unit F1 and / or other techniques are utilized to prevent the second patterned optical beam BP2LB directed at the optical beam sensor S1 from being utilized to generate a measurement signal (e.g., for determining the position and orientation of the optical beam source structure LC) for processing by the processing unit 190 at the first optical beam sensor S1.

[0093] As described above, in various embodiments, the optical beam filtering unit F1 may be utilized to block the second pattern optical beam BP2LB (e.g., rotated or moved in front of the first optical beam sensor S1). In other embodiments, (e.g., described in more detail below with respect to FIG. 13), the optical beam filtering unit F1 may include a color filter array (e.g., an array including different filters for different colors such as an RGB color filter array of an optical beam sensor). The optical beam sensor S1 having the color filter array of the optical beam filtering unit F1 may be electronically controlled and / or processed (e.g., at a particular time, to utilize only the first pattern optical beam BP1LB instead of the second pattern optical beam BP2LB and cause the optical beam sensor S1 to generate a measurement signal for processing by the processing unit 190). For example, in a particular embodiment, the color filter array may include a red wavelength filter section that passes only red light and a blue wavelength filter section that passes only blue light, and the first pattern optical beam BP1LB may be composed of red light and the second pattern optical beam BP2LB may be composed of blue light. In such an embodiment, the signal is processed such that only the first pattern optical beam BP1LB of red color is utilized (e.g., only the signals from the pixels having the red filter section are utilized), the second pattern optical beam BP2LB of blue color is not utilized (e.g., no signals from the pixels having the blue filter section are utilized), and the optical beam sensor S1 is caused to generate a measurement signal for processing by the processing unit 190 (e.g., for determining the position and orientation of the optical beam source structure LC).

[0094] In certain embodiments, the first pattern light beam BP1LB and the second pattern light beam BP2LB may have different transmission timings. As an example, the first pattern light beam BP1LB may be transmitted at a certain odd timing increment, and the second pattern light beam BP2LB may be transmitted at a certain even timing increment. In various embodiments, the measurement system 100 includes a light beam selection unit (e.g., as part of the processing unit 190 or as another part), and this light beam selection unit utilizes the signal from the light beam sensor S1 corresponding to the measurement spot generated by the first pattern light beam BP1LB at a specific timing and may be configured not to utilize the signal from the light beam sensor S1 corresponding to the measurement spot generated by the second pattern light beam BP2LB. Such filtering may be performed based on the timing at which the measurement spot is generated on the light beam sensor S1 (i.e., corresponding to the transmission timing). As described above, such filtering may be performed so that for processing by the processing unit 190 (e.g., to determine the position and orientation of the light beam source structure LC), the signal resulting from the measurement spot generated by the first pattern light beam BP1LB is utilized and the signal resulting from the measurement spot generated by the second pattern light beam BP2LB is not utilized.

[0095] In the example of FIG. 11B, compared with the example of FIG. 11A, the light beam source structure LC is moved away from the light beam sensor S1 and closer to the light beam sensor S2. In particular, the light beam source structure LC is shown to be at a distance D1' from the light beam sensor S2 and at a distance D2' from the light beam sensor S1. In various embodiments, the distance D1' and the distance D2' may be the same as or identical to the distances D1 and D2 in FIG. 11A, or may be different. In the example of FIG. 11B, the measurement system utilizes the first patterned light beam BP1LB directed at the light beam sensor S2 to generate a measurement spot that causes the light beam sensor S2 to generate a measurement signal, while the second patterned light beam BP2LB directed at the light beam sensor S2 may be configured not to be utilized as much for processing by the processing unit 190 (e.g., for determining the position and orientation of the light beam source structure LC). In contrast, the second patterned light beam BP2LB directed at the light beam sensor S1 at the distance D2' may be utilized to generate a measurement spot that causes the light beam sensor S1 to generate a measurement signal for processing by the processing unit 190 (e.g., for determining the position and orientation of the light beam source structure LC).

[0096] In various embodiments, the optical beam filtering portions F1 and F2 (and / or other filtering portions of the system) may also include portions that can be used to block or otherwise filter the first pattern optical beam BP1LB (e.g., move in front of the corresponding optical beam sensor or be used in other ways). For example, in the configuration of FIG. 11A, a portion of the optical beam filtering portion F2 (e.g., or other filtering portions of the system), where the optical beam source structure LC is determined to be at a distance D2 from the optical beam sensor S2, may be utilized to prevent the first pattern optical beam BP1LB from forming a measurement spot on the optical beam sensor S2 and / or to prevent the utilization of the measurement signal corresponding to the first pattern optical beam BP1LB. Such embodiments may be utilized, for example, in configurations that function most effectively when the optical beam sensor S2 receives and / or processes only one of the first or second pattern optical beams. In such a configuration, in the example of FIG. 11A, it is desirable for the optical beam sensor S2 to receive and / or process only the second pattern optical beam BP2LB (e.g., process the measurement signal resulting from the measurement spot) and may not process the first pattern optical beam BP1LB.

[0097] In other embodiments, the system may be configured to function effectively when the optical beam sensor S2 receives both the first and second pattern optical beams BP1LB and BP2LB simultaneously (e.g., having the measurement spots generated thereby). For example, the first pattern BP1 of the optical beam and the second pattern BP2 of the optical beam may be configured such that even when the optical beam is received simultaneously by the corresponding optical beam sensor (e.g., optical beam sensor S2) and forms measurement spots, the optical beams do not overlap or cause other problems. Regarding the concern that excessive measurement spots may be formed on the optical beam sensor S2 in FIG. 11A, it should be noted that the first pattern optical beam BP1LB has a relatively low density compared to the relatively high density of the second pattern optical beam BP2LB and thus has only a limited impact on such problems.

[0098] In various embodiments, as described above, with respect to the example of FIG. 11A, the determination as to whether to prevent the use of the second patterned light beam BP2LB directed to the first light beam sensor S1 is at least partially based on the determined distance (e.g., corresponding to distance D1) of the light beam source structure LC from the light beam sensor S1. In various embodiments, a threshold distance may be specified, and if the determined distance is less than the specified threshold distance, the second patterned light beam BP2LB may not be used. In such a configuration, if the determined distance (e.g., corresponding to distance D1) is less than the threshold distance, only the measurement signal corresponding to the first patterned light beam BP1LB may be used for processing by the processing unit 190 (e.g., for determining the position and orientation of the light beam source structure LC).

[0099] In various embodiments, the determination of the distance (e.g., corresponding to distance D1) of the light beam source structure LC from the light beam sensor (e.g., light beam sensor S1) may be determined based at least in part on position information provided from the motion control system 140 of the mobile system. As described herein, the motion control system 140 may provide position information indicating the position of the light beam source structure LC (e.g., within the measurement frame volume MFV) with the accuracy of the mobile system, whereby the distance of the light beam source structure LC from each light beam sensor (e.g., from the light beam sensor S1) can be indicated with the accuracy of the mobile system when the fixed position of the light beam sensor relative to the measurement frame volume is known.

[0100] Alternatively, or in addition, other data can be used to determine (e.g., estimate, predict, etc.) the distance from a light beam sensor (e.g., light beam sensor S1) to the light beam source structure LC (e.g., corresponding to distance D1). For example, up-to-date known position data, velocity data, direction data, etc. about the light beam source structure LC (e.g., data determined by the motion control system 140 and / or the measurement system 100) are combined with the current position data from the mobile system 110, estimated values of movement, predicted values, etc. to determine the current distance from the light beam sensor (e.g., light beam sensor S1) to the light beam source structure LC (e.g., corresponding to distance D1). As described above, the determined distance (e.g., corresponding to distance D1) is, in some embodiments, compared with a specified threshold distance to determine whether a particular patterned light beam (e.g., the second patterned light beam BP2LB) and / or the corresponding signal is utilized, blocked, or not utilized in relation to the measurement signal (e.g., for determining the position and orientation of the light beam source structure LC) processed by the processing unit 190, and / or may be evaluated or utilized in other ways.

[0101] In certain configurations, there is generally little or no time penalty when making measurements or determinations regarding both patterned light beams (e.g., configurations that utilize time multiplexing with different transmission timings, configurations that utilize a color filter array CFA, etc.). In such configurations or other cases, in various embodiments, an image from the light beam sensor can be inspected to select the pattern of the light beam that is optimal for processing (e.g., determining the position and orientation of the light beam source structure). For example, an image from the light beam sensor can be inspected to determine which pattern of the light beam generates at least one measurement spot and whether those measurement spots overlap. As a more specific example, for a particular light beam sensor, if an image shows that the measurement spots generated by the second pattern BP2 of the light beam overlap and the first pattern BP1 of the light beam generates at least one measurement spot on the light beam sensor, the first pattern BP1 of the light beam may be utilized and the second pattern BP2 of the light beam may not be utilized (e.g., an image including one or more measurement spots corresponding to the first pattern BP1 of the light beam is utilized, and an image including measurement spots corresponding to the second pattern BP2 of the light beam is not utilized). As another example, for a particular light beam sensor, if an image shows that no measurement spots are generated on the light beam sensor by the first pattern BP1 of the light beam and at least one measurement spot is generated on the light beam sensor by the second pattern BP2 of the light beam, the second pattern BP2 of the light beam may be utilized (e.g., an image including one or more measurement spots corresponding to the second pattern BP2 of the light beam is utilized).

[0102] In certain applications, the number of light beam sensors included in the sensor structure 160 can vary, and in this case, the corresponding distances from the different light beam sensors to the light beam source structure may be determined (e.g., compared to a threshold distance). In connection with the example of FIG. 4B, it is understood that in certain embodiments, the sensor structure 160 may include a number of light beam sensors. In such a configuration, when the light beam source structure is close to one side (e.g., or one corner) of the measurement frame volume MFV, it is understood that the light beam source structure will correspondingly be close to the light beam sensors on that side (e.g., or corner) of the measurement frame volume, while being far from the light beam sensors on the opposite side (or opposite corner) of the measurement frame volume.

[0103] FIG. 12 is a diagram of a first exemplary embodiment of a light beam source portion LP1'' of a light beam source structure that may be utilized to provide first and second patterns of light beams BP1 and BP2. As shown in FIG. 12, the light beam source portion LP1'' includes light sources LS1, LS2A, LS2B, and diffractive optical elements DOE1, DOE2A, DOE2B. The light source LS1 supplies light corresponding to a first wavelength, e.g., light corresponding to red light in the illustrated example. The diffractive optical element DOE1 receives and diffracts the light from the light source LS1 to form a first pattern BP1 of a light beam including the first pattern light beam BP1LB.

[0104] The light sources LS2A and LS2B supply light corresponding to a second wavelength, e.g., light corresponding to blue light in the illustrated example. The diffractive optical elements DOE2A and DOE2B each receive the light from the light sources LS2A and LS2B and diffract this light to form second light beam patterns BP2A and BP2B, respectively. The second pattern light beams BP2A and BP2B each include second pattern light beams BP2ALB and BP2BLB. The combination of the second light beam patterns BP2A and BP2B may be referred to as a second pattern BP2 of the light beam. The second pattern light beams BP2ALB and BP2BLB may both be characterized as the second pattern light beam BP2LB.

[0105] Similar to the previous embodiment, the first pattern BP1 of the light beam has a first pattern light beam BP1LB with a lower density (e.g., a wider corresponding angular interval / angle dispersion) with respect to the second pattern BP2 of the light beam having a second pattern light beam BP2LB with a higher density (e.g., a narrower corresponding angular interval / angle dispersion). The first wavelength of the first pattern light beam BP1LB (e.g., corresponding to red light) and the second wavelength of the second pattern light beam BP2LB (e.g., corresponding to blue light) have different characteristics, whereby the first pattern light beam BP1LB can be distinguished from the second pattern light beam BP2LB. In one example, as described above, in one example, the light beam filter section (e.g., light beam filter section F1 or F2) may include a filter (e.g., a color filter), and as this filter, while blocking the second pattern light beam BP2LB (e.g., preventing the second pattern light beam BP2LB from forming a measurement spot on the light beam sensor and / or its specific pixel), allowing the first pattern light beam BP1LB to pass through and form a measurement spot on the corresponding light beam sensor and / or its specific pixel, there is a red color filter.

[0106] FIG. 13 is a diagram of a color filter array CFA (e.g., used to filter patterns of light beams of different colors). In some embodiments, the color filter array CFA may be an internal component of a light beam sensor (e.g., in some examples, a type of color camera). In the example of FIG. 13, the color filter array CFA includes three types of pixel filter portions PX1, PX2, and PX3. In various embodiments, the pixel filter portion PX1 corresponds to a red filter portion, the pixel filter portion PX2 corresponds to a blue filter portion, and the pixel filter portion PX3 corresponds to a green filter portion. As described above with respect to FIG. 12, in one embodiment, the first patterned light beam BP1LB is red and the second patterned light beam BP2LB is blue. In such an embodiment, a light beam filter portion (e.g., light beam filter portion F1 or F2) including the color filter array CFA of FIG. 13 may be used to determine / control whether a certain patterned light beam (e.g., the second patterned light beam BP2LB) is used to generate a measurement signal for processing by the processing unit 190 (e.g., determining the position and orientation of the light beam source structure LC).

[0107] As an example, when the second patterned light beam BP2LB is not used, the light beam sensor having the color filter array CFA may be controlled such that pixels corresponding to the pixel filter portion PX2 (e.g., the blue filter portion) do not provide a measurement signal for processing by the processing unit 190 (e.g., determining the position and orientation of the light beam source structure LC). In such a configuration, the light beam sensor having the color filter array CFA is controlled such that signals from pixels that correspond to the pixel filter portion PX1 (e.g., the red filter portion) and generate a measurement signal based on a measurement spot formed by the first patterned light beam PB1LB are used for processing by the processing unit 190.

[0108] FIG. 14 is a diagram of a second exemplary embodiment of a light beam source portion LP1''' of a light beam source structure that may be used to provide first and second light beam patterns BP1 and BP2. In the example of FIG. 14, the light source portion LP1''' includes light beam sources LS1, LS2A, and LS2B, and diffraction optical elements DOE1, DOE2A, and DOE2B. In some embodiments, a separate polarization element (not shown) may be provided. In the example of FIG. 14, the light source LS1 directs light having a first circular polarization toward the diffraction optical element DOE1, and this diffraction optical element DOE1 diffracts the light to form a first pattern BP1 of a light beam including a relatively low-density first pattern light beam BP1LB.

[0109] The light beam sources LS2A and LS2B direct light having a second circular polarization (i.e., a polarization opposite to the first circular polarization of the light directed by the light source LS1), and this light is received and diffracted by the diffraction optical elements DOE2A and DOE2B to form second pattern light beams BP2A and BP2B including relatively high-density second pattern light beams BP2ALB and BP2BLB. In various embodiments, the second pattern BP2 of the light beam may be characterized as including the second light beam patterns BP2A and BP2B, and the second pattern light beam BP2LB may be characterized as including the second pattern light beams BP2ALB and BP2BLB.

[0110] The first circular polarization of the light directed from the first light source is indicated by the first polarization indicator PI1, and the second circular polarization of the light directed from the light sources LS2A and LS2B (e.g., a polarization opposite to the first circular polarization) is indicated by the polarization indicators PI2A and PI2B. In various embodiments, the first circular polarization of the first pattern light beam BP1LB and the second circular polarization of the second pattern light beam BP2LB correspond to different characteristics that enable the first pattern light beam BP1LB to be distinguished from the second pattern light beam BP2LB. As an example, in one embodiment, the light beam filtering unit (e.g., the light beam filtering unit F1 or F2) may include a polarization filter for filtering a specific light beam. Referring to the example of FIG. 11A, the light beam filtering unit F1 may include a polarization filter that passes the first pattern light beam BP1LB having the first circular polarization (e.g., forms a measurement spot on the light beam sensor S1) and blocks the second pattern light beam BP2LB having the second circular polarization.

[0111] FIG. 15 is a diagram of a third exemplary embodiment of an optical beam source structure LP1'''' that may be utilized to provide first and second pattern optical beams BP1 and BP2. In the example of FIG. 15, the optical beam source structure LP1'''' includes a light source LS1, a wave plate WP, a reflective element RE1, a beam splitter BS, and diffractive optical elements DOE1 and DOE2A. Light from the light source LS1 is shown to have linear polarization by a polarization indicator PI-L and is supplied to a wave plate WP (e.g., a quarter-wave plate) and reflected by a reflective surface RE1 toward the beam splitter BS. In various embodiments, reflection at a near-normal beam splitter BS may change the sign of the circular polarization of the light, thereby reducing the number of quarter-wave plates required (e.g., the illustrated configuration includes only a single quarter-wave plate WP). In some embodiments, a circular polarizer may be used instead of a wave plate. Light transmitted through the beam splitter BS is indicated by a polarization indicator PI1 to have a first circular polarization, and light reflected from the beam splitter BS is indicated by a second polarization indicator PI2 to have a second circular polarization (e.g., opposite to the first circular polarization).

[0112] The light of the first circular polarization is diffracted by a first diffractive optical element DOE1 to include a relatively low-density first pattern optical beam BP1LB and form a first pattern BP1 of an optical beam having the first circular polarization. The light of the second circular polarization is diffracted by a diffractive optical element DOE2A to include a relatively high-density second pattern optical beam BP2ALB and form a second pattern BP2A of an optical beam having the second circular polarization. In various embodiments, the second pattern BP2A of the optical beam and the second pattern BP2BLB of the optical beam may correspond to the second pattern optical beam BP2 and the second pattern optical beam BP2LB (e.g., similar to those in FIG. 14). The first polarization of the first pattern optical beam BP1LB and the second polarization of the second pattern optical beam BP2LB (e.g., this is a polarization opposite to the first polarization) correspond to different characteristics that enable the first pattern optical beam BP1LB to be distinguished from the second pattern optical beam BP2LB, similar to the example described above with respect to FIG. 14.

[0113] Regarding the embodiments of FIGS. 12, 14, and 15, in various embodiments, the diffractive optical element (DOE) for generating different patterns of light beams may have different characteristics (e.g., for operating with respect to the corresponding angular dispersion and / or with respect to different characteristics of the first and second patterns of the light beam). In certain embodiments, other configurations may be used as part of the light beam source structure to provide the first and second pattern light beams. For example, a particular type of variable projector (e.g., a variable projector chip) that can generate different light beam patterns and switch using a single device may be utilized. In one embodiment of such a configuration, the first and second pattern light beams may be provided at different transmission timings. In various embodiments, metasurfaces and / or metamaterials may also be utilized, additionally or alternatively, to generate patterns of light beams having different characteristics. For example, a configuration utilizing such metasurfaces and / or metamaterials may utilize only a single light source that can generate different wavelengths for the first and second light beam patterns, or alternatively, different light sources may be utilized to provide different wavelengths. However, it is directed towards a common configuration that utilizes metasurfaces and / or metamaterials to provide the first and second light beam patterns.

[0114] FIG. 16 is a flow diagram showing one exemplary embodiment of routine 1600 for operating a measurement system. At block 1610, the light beam source structure (i.e., the light beam source structure of the measurement system) is operated to direct the first pattern BP1 of the light beam and the second pattern BP2 of the light beam to the light beam sensor of the sensor structure (i.e., the sensor structure of the measurement system) to indicate the position and orientation of the light beam source structure. In various embodiments, the light beam source structure is coupled to at least one of an end tool or an end tool mounting structure of a movement system that moves the end tool. The position and orientation of the light beam source structure indicate the position and orientation of the end tool. The sensor structure includes a plurality of light beam sensors arranged at fixed positions, including a first light beam sensor at at least a first position and a second light beam sensor at a second position. At least a portion of the light beam directed to and received by the light beam sensor generates a measurement spot at a position on the light beam sensor and generates a measurement signal corresponding to the light beam sensor. The first pattern BP1 of the light beam has a lower density first pattern light beam BP1LB compared to the second pattern BP2 of the light beam having a higher density second pattern light beam BP2LB.

[0115] At block 1620, the measurement signals from the light beam sensors of the sensor structure are processed to determine the position and orientation of the light beam source structure. At least a first position of the light beam source structure is at a first distance from the first light beam sensor and at a second distance from the second light beam sensor, and when the second distance is greater than the first distance, i) one or more first pattern light beams BP1LB directed to the first light beam sensor are utilized to cause the first light beam sensor to generate a measurement signal for processing to determine the position and orientation, and ii) the second pattern light beam BP2LB directed to the first light beam sensor is not utilized to cause the first light beam sensor to generate a measurement signal for processing to determine the position and orientation. Further, one or more second pattern light beams BP2LB directed to the second light beam sensor are utilized to cause the second light beam sensor to generate a measurement signal for processing to determine the position and orientation.

[0116] In various embodiments, routine 1600 may further include receiving position information from a movement system 110 that moves an end tool ETL, the position information indicating, with movement system accuracy, a first distance of a light beam source structure LC from a first light beam sensor, and a second patterned light beam BP2LB directed at the first light beam sensor that is at least partially based on the first distance indicated by the position information from the movement system 110 is not utilized to generate a measurement signal for a process of determining a position and orientation at the first light beam sensor.

[0117] In various embodiments, when at least a second position of the light beam source structure LC is at a third distance from the first light beam sensor and at a fourth distance from the second light beam sensor and the third distance is greater than the fourth distance, i) one or more first patterned light beams BP1LB directed at the second light beam sensor are utilized to generate a measurement signal for a process of determining a position and orientation at the second light beam sensor, ii) a second patterned light beam BP2LB directed at the second light beam sensor is not utilized to generate a measurement signal for a process of determining a position and orientation at the second light beam sensor, and iii) one or more second patterned light beams BP2LB directed at the first light beam sensor are utilized to generate a measurement signal for a process of determining a position and orientation at the first light beam sensor.

[0118] Various exemplary embodiments of the present disclosure having various features and elements annotated with reference numerals found in FIGS. 1 - 16 are described below. It is to be understood that the reference numerals are added to illustrate the exemplary embodiments and the features and elements are not limited to the specific embodiments illustrated in FIGS. 1 - 16.

[0119] As described in this specification, the size of the region of interest (ROI) may vary (e.g., as described with respect to the examples in FIGS. 7(a), 7(b), 8(a), and 8(b)). As one specific example, the determined region of interest on the light beam sensor generally may be larger because it includes a larger measurement spot generated when the light beam source structure is relatively close to the light beam sensor. Correspondingly, the region of interest specified on the light beam sensor generally may be smaller because it includes a smaller measurement spot generated when the light beam source structure is relatively far from the light beam sensor.

[0120] The measurement system 100 includes a sensor structure 160, a light beam source structure LC, and a processing unit 190. The sensor structure 160 includes a plurality of light beam sensors S1 to S4 arranged at fixed positions, including a first light beam sensor arranged at at least a first position and a second light beam sensor arranged at a second position. The light beam source structure LC is configured to direct a first pattern BP1 of the light beam and a second pattern BP2 of the light beam toward the light beam sensors of the sensor structure 160 (e.g., including the light beam sensors S1 to S4) so as to indicate the position and orientation of the light beam source structure LC.

[0121] The light beam source structure LC is configured to be coupled to at least one of the end tool ETL or the end tool attachment structure ETMC. At least a part of the light beam directed toward and received by the light beam sensor is configured to generate a measurement spot SP at a position on the light beam sensor that causes the corresponding light beam sensor to generate a measurement signal. The first pattern BP1 of the light beam has a lower density first pattern light beam BP1LB compared to the second pattern BP2 of the light beam, which has a higher density second pattern light beam BP2LB.

[0122] The processing unit 190 is configured to process the measurement signals from the optical beam sensors of the sensor structure 160 to determine the position and orientation of the optical beam source structure LC. The measurement system 100 is configured such that at least a first position of the optical beam source structure LC is at a first distance from the first optical beam sensor and at a second distance from the second optical beam sensor, and the second distance is greater than the first distance, and i) one or more first pattern optical beams BP1LB directed at the first optical beam sensor are utilized to cause the first optical beam sensor to generate a measurement signal for processing by the processing unit 190, ii) a second pattern optical beam BP2LB directed at the first optical beam sensor is not utilized to cause the first optical beam sensor to generate a measurement signal for processing by the processing unit 190, and iii) one or more second pattern optical beams BP2LB directed at the second optical beam sensor are utilized to cause the second optical beam sensor to generate a measurement signal for processing by the processing unit 190.

[0123] In various embodiments, the first pattern optical beam BP1LB and the second pattern optical beam BP2LB have at least one different characteristic that can distinguish the first pattern optical beam BP1LB from the second pattern optical beam BP2LB. In various embodiments, the at least one different characteristic is at least one of a different wavelength, a different polarization, or a different transmission timing. In various embodiments, the measurement system further comprises at least a first optical beam selection unit configured to operate based on the at least one different characteristic. In various embodiments, the selection unit may include an optical beam filtering unit (e.g., including a plurality of optical beam filtering units such as in front of each optical beam sensor as shown in the examples of FIGS. 11A and 11B), and / or may include a part of the processing unit 190 or other processing unit that selects, filters, and / or blocks the signals generated by the optical beam, and this processing unit can operate based on characteristics such as different transmission timings of the optical beam.

[0124] In various embodiments, the first light beam selection unit is configured to prevent the second patterned light beam BP2LB directed to the first light beam sensor from being used to generate a measurement signal at the first light beam sensor for processing by the processing unit 190 (e.g., determination of the position and orientation of the light beam source structure LC), based at least in part on the indication of the first distance between the light beam source structure LC and the first light beam sensor. In various embodiments, the first light beam selection unit is configured to be used to perform at least one of: i) preventing the second patterned light beam BP2LB from reaching the first light beam sensor, or ii) preventing the measurement signal caused by the second patterned light beam BP2LB at the first light beam sensor from being processed by the processing unit 190. As an example of such a feature, in relation to the example of FIG. 11A, based at least in part on the indication of the first distance D1 between the light beam source structure LC and the first light beam sensor S1, the first light beam selection unit (e.g., the light beam filtering unit F1) is configured to prevent the second patterned light beam BP2LB directed to the first light beam sensor S1 from being used to generate a measurement signal at the first light beam sensor for processing by the processing unit 190 (e.g., the light beam filtering unit F1 blocks the second patterned light beam BP2LB from reaching the first light beam sensor S1).

[0125] In various embodiments, at least one different characteristic between the first and second patterned light beams BP2LB is at least one of a different wavelength or a different polarization (e.g., as illustrated by the different configurations of FIGS. 12, 14, and 15), and the first light beam selection unit includes a first light filtering unit (e.g., light filtering unit F1) including at least one of a wavelength filter or a polarization filter that moves in front of the first light beam sensor to block the second patterned light beam BP2LB. In various embodiments, the measurement system 100 further includes at least a second light beam selection unit, which is configured to operate based on at least one different characteristic and includes a second light beam filtering unit (e.g., light beam filtering unit F2) including at least one of a wavelength filter or a polarization filter, and the first and second light beam filtering units are configured to be used to perform filtering on the first and second light beam sensors, respectively (e.g., as shown in the examples of FIGS. 11A and 11B).

[0126] In various embodiments, the measurement system 100 is configured such that at least a second position of the light beam source structure LC (e.g., the second position shown in FIG. 11B as compared to the first position shown in FIG. 11A) is at a third distance (e.g., distance D2') from the first light beam sensor and at a fourth distance (e.g., distance D1') from the second light beam sensor, and the third distance is greater than the fourth distance, and i) one or more first patterned light beams BP1LB directed to the second light beam sensor are utilized to cause the second light beam sensor to generate a measurement signal for processing by the processing unit 190, ii) the second patterned light beam BP2LB directed to the second light beam sensor is not utilized to cause the second light beam sensor to generate a measurement signal for processing by the processing unit 190, and iii) one or more second patterned light beams BP2LB directed to the first light beam sensor are utilized to cause the first light beam sensor to generate a measurement signal for processing by the processing unit 190.

[0127] In various embodiments, the light beam source structure LC is configured to direct a first pattern BP1 of a light beam and a second pattern BP2 of the light beam simultaneously towards the light beam sensor of the sensor structure 160. In various embodiments, the motion control system 140 is configured to provide position information indicating, with motion system accuracy, that the light beam source structure LC is at a first distance (e.g., distance D1 in FIG. 11A) from the first light beam sensor, and based at least in part on the first distance indicated by the position information from the motion control system 140, the second pattern light beam BP2LB directed towards the first light beam sensor is such that the first light beam sensor is not utilized to generate a measurement signal for processing by the processing unit 190. In various embodiments, the measurement system includes at least a first light beam selection unit (e.g., the light beam filtering unit F1, a part of the processing unit 190, etc.), and based at least in part on the first distance indicated by the position information from the motion control system 140, the first light beam selection unit is configured such that the second pattern light beam BP2LB directed towards the first light beam sensor is not utilized by the first light beam sensor to generate a measurement signal.

[0128] As an example, based on the determined distance D1, the optical beam filtering unit F1 may be arranged in front of the first optical beam sensor S1 such that the optical beam filtering unit F1 having a filter that is operated to rotate in front of the first optical beam sensor S1, so as to block the second patterned optical beam BP2LB from reaching the sensing area of the first optical beam sensor S1. As another example, the optical beam filtering unit F1 may similarly operate to filter the first patterned optical beam BP1LB and / or the signal generated thereby from the second patterned optical beam BP2LB and / or the signal generated thereby (e.g., in some cases, without the need for movement), and may include a color filter array CFA (e.g., as illustrated in FIG. 13) and / or other components or mechanisms. As another example, at least a part of the processing unit 190 (or another processing unit) may be characterized as an optical beam selection unit configured to select the signal from the first optical beam sensor S1 resulting from the first patterned optical beam BP1LB, but not to select the signal from the first optical beam sensor S1 resulting from the second patterned optical beam BP2LB (e.g., when the first and second patterned optical beams have first and second transmission timings respectively, only the signal corresponding to the first transmission timing may be selected and / or otherwise processed by the processing unit, such as for determining the position and orientation of the optical beam source configuration LC).

[0129] In various embodiments, each of the light beam sensors (e.g., including light beam sensors S1 to S4) includes a two-dimensional position detection sensor, and the measurement signal from the light beam sensor indicates the two-dimensional position of the measurement spot SP on the light beam sensor generated by the light beam. In various embodiments, the measurement frame volume MFV is at least partially defined by a plurality of light beam sensors arranged at fixed positions, and this measurement frame volume MFV is configured to surround at least a part of the moving volume MV, and the first and second light beam sensors S1 and S2 are arranged on opposite sides of the measurement frame volume MFV. In various embodiments, the light beam source structure LC includes one or more diffractive optical elements DOE (e.g., the diffractive optical elements in FIGS. 3, 12, 14, and / or 15), and at least a part of the light beam from the light beam source structure LC is a diffracted light beam.

[0130] In various embodiments, the motion control system 140 is configured to detect and control the position and orientation of the end tool ETL at a level of accuracy defined as the motion system accuracy, at least partially based on using a plurality of position sensors SEN included in the movable structure MAC (e.g., as shown in FIG. 1). The processing unit 190 is operable to determine the position and orientation of the end tool ETL with an accuracy higher than the motion system accuracy, at least partially based on processing the measurement signals from the light beam sensors (e.g., including light beam sensors S1 to S4) to determine the position and orientation of the light beam source structure LC, where the position and orientation of the light beam source structure LC indicate the position and orientation of the end tool ETL.

[0131] As an example, at the first position of the light beam source structure LC (for example, the position as shown in FIG. 11A), the light beam directed from the light beam source structure LC toward the sensor structure 160 includes the first pattern light beam BP1LB, and the determination of which light beam sensor the first pattern light beam BP1LB is directed to is at least partially based on the detected position and orientation of the end tool ETL determined using a plurality of position sensors included in the movable structure MAC. In this example, the light beam sensor to which the first pattern light beam is directed is the first light beam sensor S1, and the processing unit 190 is operable to determine the position and orientation of the end tool ETL at an accuracy level better than the moving system accuracy at least partially based on processing the first measurement signal from the first light beam sensor S1. This first measurement signal indicates the position of the first measurement spot SP1 formed on the first light beam sensor S1 by the first pattern light beam BP1LB (for example, examples of the position of the measurement spot and the display / determination of the corresponding positions of the light beam source structure and / or the end tool ETL are described above in relation to FIGS. 5A(a)-5B(h) and FIGS. 6(a)-6(c)).

[0132] As described above, it may generally be desirable for the measurement spots formed on the light beam sensors not to overlap. It may also generally be desirable for at least one measurement spot to be formed on the light beam sensor. Regarding preventing the measurement spots from overlapping (especially when the measurement spots are relatively large), when the light beam source structure is relatively close to the light beam sensor, it may be desirable for the light beam source structure to generate measurement spots with a low density. Regarding having at least one measurement spot formed on the light beam sensor, when the light beam source structure is relatively far from the light beam sensor, it may be desirable for the light beam source structure to generate measurement spots with a high density.

[0133] As described above, in various embodiments, a first pattern BP1 of the light beam and a second pattern BP2 of the light beam may be provided, and the first pattern BP1 of the light beam may have a first pattern light beam BP1LB with a lower density relative to the second pattern BP2 of the light beam, which may have a second pattern light beam BP2LB with a higher density. In various embodiments, the first and second light beam patterns BP1 and BP2 may be distinguishable from each other by having different characteristics (e.g., different wavelengths, different circular polarizations, different transmission timings, etc.). Embodiments using different wavelengths are described in connection with FIG. 12, and embodiments using different circular polarizations are described in connection with FIGS. 14 and 15.

[0134] Preferred embodiments of the present disclosure have been illustrated and described, but numerous variations in the illustrated and described sequence of the features, configurations, and operations will be apparent to those skilled in the art based on the present disclosure. Various alternative forms may be used to implement the principles disclosed herein. Additionally, the various implementations described above can be combined to provide further implementations. All U.S. patents and U.S. patent applications referred to herein are hereby incorporated by reference in their entirety. Aspects of the embodiments can be modified to adopt concepts from various patents and applications to provide further embodiments as needed.

[0135] In light of the above detailed description, these and other changes can be made to the embodiments. In general, in the following claims, the terms used should not be construed as limiting the claims to the specific embodiments disclosed herein and the claims should be construed to include all possible embodiments along with the full scope of equivalents to which such claims are entitled.

Claims

1. 1. A metrology system for use with a motion system for moving an end tool, comprising: The mobile system comprises: a movable structure including an end tool mounting structure configured to mount an end tool; a motion control system configured to control a position and orientation of the end tool based at least in part on controlling the moveable structure to move at least a portion of the end tool attached to the end tool mounting structure within a movement volume; and Equipped with The measurement system includes: a sensor structure including a plurality of optical beam sensors disposed at fixed locations, including at least a first optical beam sensor at a first location and a second optical beam sensor at a second location; a light beam source structure for directing a first pattern of light beams and a second pattern of light beams to a light beam sensor of the sensor structure to indicate a position and orientation of the light beam source structure; the optical beam source structure is configured to be coupled to at least one of an end tool or the end tool mounting structure; at least a portion of the light beam directed at and received by the light beam sensor is configured to generate a measurement spot at a location on the light beam sensor that causes the light beam sensor to generate a corresponding measurement signal. The first pattern of the light beam has a low density of the first pattern light beam compared to the second pattern of the light beam having a high density of the second pattern light beam. a light beam source structure; a processor configured to process the measurement signals from the light beam sensors of the sensor structure to determine a position and orientation of the light beam source structure; Equipped with the metrology system is configured such that at least a first position of the light beam source structure is at a first distance from a first light beam sensor and at a second distance from a second light beam sensor, the second distance being greater than the first distance; i) one or more first patterned light beams directed to the first light beam sensor are utilized to cause the first light beam sensor to generate a measurement signal for the processing by the processing unit; ii) a second patterned light beam directed to the first light beam sensor is not utilized to cause the first light beam sensor to generate a measurement signal for the processing by the processing unit; and iii) one or more second patterned light beams directed to the second light beam sensor are utilized to cause the second light beam sensor to generate a measurement signal for the processing by the processing unit. Measurement system.

2. the first patterned light beam and the second patterned light beam have at least one different characteristic that allows the first patterned light beam to be distinguished from the second patterned light beam. The measurement system of claim 1 .

3. the at least one different characteristic is at least one of a different wavelength, a different polarization, or a different transmission timing; The measurement system of claim 2 .

4. and further comprising at least one first light beam selector configured to operate based on the at least one different characteristic. The measurement system of claim 2 .

5. and based at least in part on an indication of the first distance of the light beam source structure from the first light beam sensor, the first light beam selection unit is configured to prevent the second pattern light beam directed to the first light beam sensor from being utilized by the first light beam sensor to generate a measurement signal for the processing by the processing unit. The measurement system of claim 4.

6. The first light beam selection unit is configured to be utilized to at least one of: i) block the second pattern light beam BP2LB from reaching the first light beam sensor; or ii) prevent a measurement signal resulting from the second pattern light beam BP2LB at the first light beam sensor from being processed by the processing unit 190. The measurement system of claim 5 .

7. the at least one different characteristic between the first pattern light beam and the second pattern light beam is at least one of different wavelengths or different polarizations, and the first light beam selection unit includes a first light beam filtering unit including at least one of a wavelength filter or a polarization filter configured to move in front of the first light beam sensor to block the second pattern light beam. The measurement system of claim 5 .

8. and further comprising at least a second light beam selection unit, i) configured to operate based on said at least one different characteristic, and ii) comprising a second light beam filtering unit including at least one of a wavelength filter or a polarization filter, the first and second light beam filtering units being configured to be utilized to perform filtering on the first and second light beam sensors, respectively. The measurement system of claim 7.

9. the metrology system is configured such that at least a second position of the light beam source structure is at a third distance from a first light beam sensor and at a fourth distance from a second light beam sensor, the third distance being greater than the fourth distance; i) one or more first pattern light beams directed to the second light beam sensor are utilized to cause the second light beam sensor to generate a measurement signal for the processing by the processing unit; and ii) a second pattern light beam directed to the second light beam sensor is not utilized to cause the second light beam sensor to generate a measurement signal for the processing by the processing unit; iii) the one or more second pattern light beams directed to the first light beam sensor are utilized to cause the first light beam sensor to generate a measurement signal for the processing by the processing unit; The measurement system of claim 1 .

10. the light beam source structure is configured to simultaneously direct the first pattern of light beams and the second pattern of light beams to the light beam sensor of the sensor structure. The measurement system of claim 1 .

11. the motion control system is configured to provide position information indicative of a first distance of the light beam source structure from the first light beam sensor with a motion system precision, and based at least in part on the first distance indicated by the position information from the motion control system, the second pattern light beam directed to the first light beam sensor is not utilized to cause the first light beam sensor to generate a measurement signal for the processing by the processing unit. The measurement system of claim 1 .

12. Further comprising at least a first light beam selection unit; and based at least in part on the first distance indicated by position information from the motion control system, the first light beam selection unit is configured to prevent a second pattern light beam directed to the first light beam sensor from being utilized to cause the first light beam sensor to generate a measurement signal for the processing by the processing unit. The measurement system of claim 11.

13. each of the light beam sensors comprises a two-dimensional position detection sensor, the measurement signal from the light beam sensor being indicative of a two-dimensional position of a measurement spot on the light beam sensor generated by a light beam; The measurement system of claim 1 .

14. a metrology frame volume at least partially defined by the plurality of optical beam sensors disposed at the fixed locations, the metrology frame volume being ... The measurement system of claim 1 .

15. the light beam source structure comprises one or more diffractive optical elements, and at least a portion of the light beams from the light beam source structure are diffracted light beams. The measurement system of claim 1 .

16. the motion control system is configured to detect and control the position and orientation of the end tool with a level of accuracy defined as a motion system accuracy based at least in part on detecting and controlling the position and orientation of the end tool using a plurality of position sensors included in the movable structure; the processing unit is operable to determine a position and orientation of the end tool with a level of accuracy better than the motion system accuracy based at least in part on processing the measurement signals from the light beam sensor to determine a position and orientation of the light beam source structure indicative of the position and orientation of the end tool. The measurement system of claim 1 .

17. For the first position of the light beam source structure, the light beam directed by the light beam source structure to the sensor structure includes a first light pattern beam, and a determination of which light beam sensor the first pattern light beam is directed to is based at least in part on a sensed position and orientation of the end tool, determined using the plurality of position sensors included in the movable structure; the light beam sensor to which the first patterned light beam is directed; and the processing unit is operable to determine a position and orientation of the end tool with an accuracy greater than the motion system accuracy based at least in part on processing a first measurement signal from the first light beam sensor indicative of a position of a first measurement spot formed by the first pattern light beam on the first light beam sensor; The measurement system of claim 16.

18. 1. A method of operating a metrology system including an optical beam source structure, comprising: operating the light beam source structure to direct a first pattern of light beams and a second pattern of light beams toward a light beam sensor of a sensor structure to indicate a position and orientation of the light beam source structure; Equipped with the optical beam source structure is coupled to at least one of an end tool mounting structure of an end tool or a motion system for moving the end tool; the position and orientation of the light beam source structure indicates the position and orientation of the end tool; the sensor structure includes a plurality of optical beam sensors disposed at fixed locations, including at least a first optical beam sensor at a first location and a second optical beam sensor at a second location; at least a portion of the light beam directed at and received by the light beam sensor generates a measurement spot at a location on the light beam sensor, causing the light beam sensor to generate a corresponding measurement signal; The first pattern of the light beam has a low density of the first pattern light beam compared to the second pattern of the light beam having a high density of the second pattern light beam, processing the measurement signals from the light beam sensors of the sensor structure to determine a position and orientation of the light beam source structure; when a first position of the light beam source structure is at a first distance from the first light beam sensor and at a second distance from the second light beam sensor, the second distance being greater than the first distance; i) one or more first pattern light beams directed to the first light beam sensor are utilized to cause the first light beam sensor to generate measurement signals for the process of determining the position and orientation; and ii) a second pattern light beam directed to the first light beam sensor is not utilized to cause the first light beam sensor to generate measurement signals for the process of determining the position and orientation; iii) one or more second patterned light beams directed to the second light beam sensor are utilized to cause the second light beam sensor to generate measurement signals for the processing to determine the position and orientation; method.

19. receiving position information from the motion system that moves the endotool; Further equipped with the position information from the motion system indicates a first distance of the light beam source structure from the first light beam sensor with motion system precision, and based at least in part on the first distance indicated by the position information from the motion system, the second pattern light beam directed to the first light beam sensor is not utilized to cause the first light beam sensor to generate a measurement signal for the processing to determine the position and orientation.

20. The method of claim 18.

20. when a second position of the light beam source structure is at a third distance from the first light beam sensor and at a fourth distance from the second light beam sensor, the third distance being greater than the fourth distance; i) one or more first patterned light beams directed to the second light beam sensor are utilized to cause the second light beam sensor to generate measurement signals for the process of determining the position and orientation; and ii) a second patterned light beam directed to the second light beam sensor is not utilized to cause the second light beam sensor to generate measurement signals for the process of determining the position and orientation; iii) one or more second patterned light beams directed at the first light beam sensor are utilized to cause the first light beam sensor to generate measurement signals for the processing to determine the position and orientation; 20. The method of claim 18.

21. a sensor structure including a plurality of optical beam sensors arranged at fixed positions, including at least a first optical beam sensor at a first position and a second optical beam sensor at a second position; a light beam source structure for directing a first pattern of light beams and a second pattern of light beams to a light beam sensor of the sensor structure to indicate a position and orientation of the light beam source structure; the optical beam source structure is configured to be coupled to at least one of an end tool mounting structure of an end tool or a motion system for moving the end tool; the position and orientation of the light beam source structure indicates the position and orientation of the end tool; at least a portion of the light beam directed at and received by the light beam sensor is configured to generate a measurement spot at a location on the light beam sensor that causes the light beam sensor to generate a corresponding measurement signal. The first pattern BP1 of the light beam has a low density of the first pattern light beam compared to the second pattern of the light beam having a high density of the second pattern light beam. a light beam source structure; a processor configured to process the measurement signals from the light beam sensors of the sensor structure to determine a position and orientation of the light beam source structure; Equipped with the metrology system is configured such that at least a first position of the light beam source structure is at a first distance from a first light beam sensor and at a second distance from a second light beam sensor, the second distance being greater than the first distance; i) one or more first pattern light beams directed to the first light beam sensor are utilized to cause the first light beam sensor to generate a measurement signal for the processing by the processing unit, ii) a second pattern light beam directed to the first light beam sensor is not utilized to cause the first light beam sensor to generate a measurement signal for the processing by the processing unit, and iii) one or more second pattern light beams directed to the second light beam sensor are utilized to cause the second light beam sensor to generate a measurement signal for the processing by the processing unit. Measurement system.

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