Apparatus and method for aligning a robotic arm with a sample tube carrier - Patent Application 20070122997

Abstract

An apparatus for aligning a robotic arm in an automated sample analysis system includes a robotic arm, a sample tube carrier, a plurality of optical components (e.g., including one or more cameras), and a controller. The controller is operable to process images received from the optical components to determine a first set of coordinates of a first marker relative to the sample tube carrier and to determine a second set of coordinates of a second marker relative to the robotic arm. The controller is further operable to adjust a position of the robotic arm and / or the sample tube carrier in response to an excessive offset between the first and second sets of coordinates. In some embodiments, the positioning tool includes first and second markers thereon. Methods for aligning a robotic arm with a sample tube carrier in an automated sample analysis system are also provided, as well as other aspects.

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit of U.S. Provisional Patent Application No. 63 / 148,533, filed February 11, 2021, and entitled "APPARATUS AND METHODS FOR ALIGNING A ROBOTIC ARM WITH A SAMPLE TUBE CARRIER," the entire disclosure of which is incorporated by reference for all purposes.

[0002] SUMMARY The present disclosure relates to a system for transporting biological liquid containers by robotics. [Background technology]

[0003] In medical testing and processing, the use of robotics can minimize exposure to or contact with biological liquid samples (e.g., blood, urine, etc.) and / or increase productivity. For example, in some automated test processing systems (hereinafter referred to as "automated sample analysis systems"), biological liquid containers (e.g., test tubes, vials, etc., hereinafter referred to as "sample tubes") can be transported to and from sample tube carriers within the automated sample analysis system and to and from testing or processing sites.

[0004] Inaccurate alignment of the robotic arm, which may have grippers configured to hold sample tubes, can result in inaccurate positioning of the robotic arm, which can cause collisions or jams between the grippers and the sample tubes and / or between the sample tubes and the sample tube carrier and / or other structures in the automated sample analysis system. Furthermore, misalignment of the robotic arm can cause the grippers to not coordinate the lifting and placing of sample tubes, which can contribute to unwanted sample spillage. Summary of the Invention [Problem to be solved by the invention]

[0005] Therefore, a method and apparatus for improving the accuracy of positioning a robotic arm relative to an object, such as a sample tube carrier, in an automated sample analysis system is desirable. [Means for solving the problem]

[0006] In some embodiments, an apparatus for aligning a robotic arm in an automated sample analysis system is provided, the apparatus including a robotic arm configured to hold and move sample tubes. The apparatus also includes: a sample tube carrier configured to hold a sample tube; a positioning tool configured to be held by and moved by the robotic arm and held on the sample tube carrier; multiple optical components; and a controller. The controller is operable to process images received from the multiple optical components of the positioning tool held on the sample tube carrier to determine coordinates of a first point on the positioning tool. The controller is also operable to process images received from the multiple optical components of the positioning tool held by the robotic arm to determine coordinates of a second point on the positioning tool. The controller is further operable to cause movement of the positioning tool held by the robotic arm or held on the sample tube carrier in response to the coordinates of the second point exceeding a predetermined deviation from the coordinates of the first point.

[0007] In some embodiments, another apparatus for aligning a robotic arm is provided, the apparatus including a sample tube carrier configured to hold a sample tube and having a first marker thereon. The apparatus also includes a robotic arm including a gripper configured to hold and move the sample tube and having a second marker thereon. The apparatus further includes a plurality of optical components and a controller operably connected to the robotic arm and the plurality of optical components. The controller is operable to process images of the sample tube carrier received from the plurality of optical components to determine coordinates of the first marker. The controller is also operable to process images of the gripper received from the plurality of optical components to determine coordinates of the second marker. The controller is further operable to cause movement of the gripper via the robotic arm or movement of the sample tube carrier via the movable track in response to the coordinates of the second marker exceeding a predetermined deviation from the coordinates of the first marker.

[0008] In some embodiments, a method for positioning a robotic arm in an automated sample analysis system is provided, the method including identifying a location of a first marker relative to a sample tube carrier, identifying a location of a second marker relative to the robotic arm, determining coordinates of the first marker location using a plurality of optical components and a controller, determining coordinates of the second marker location using the plurality of optical components and the controller, and adjusting the position of the robotic arm or the sample tube carrier via the controller in response to the coordinates of the second marker location exceeding a predetermined deviation from the coordinates of the first marker location.

[0009] Still other aspects, configurations, and advantages of the present disclosure will become readily apparent from the following detailed description and illustrations of several exemplary embodiments and implementations, including the best mode contemplated for carrying out the invention. The present disclosure is susceptible to other various embodiments, and its several details can be modified in various respects without departing from the scope of the present disclosure. For example, although the following description is directed to an automated sample analysis system, the present robotic arm alignment apparatus and method are readily applicable to other systems employing robotics where high-precision placement of objects handled by the robotics is desired. The present disclosure includes all modifications, equivalents, and alternatives falling within the scope of the claims (see further below).

[0010] The drawings described below are for illustrative purposes and are not necessarily drawn to scale. Accordingly, the drawings and description should be interpreted as illustrative in nature and not restrictive. The drawings are not intended to limit the scope of the invention in any way. [Brief explanation of the drawings]

[0011] [Figure 1] 1 shows a schematic side view of a robot arm alignment device according to embodiments provided herein. [Figure 2] 2 shows a schematic plan view of an optical component setup that can be used in the robotic arm alignment device of FIG. 1 according to embodiments provided herein. [Figure 3] 2 shows a simplified schematic diagram of various arrangements of optical components that can be used in the robotic arm alignment device of FIG. 1 according to embodiments provided herein. [Figure 4] 2 shows a simplified schematic diagram of various arrangements of optical components that can be used in the robotic arm alignment device of FIG. 1 according to embodiments provided herein. [Figure 5] 2 shows a simplified schematic diagram of various arrangements of optical components that can be used in the robotic arm alignment device of FIG. 1 according to embodiments provided herein. [Figure 6]2 shows a simplified schematic diagram of various arrangements of optical components that can be used in the robotic arm alignment device of FIG. 1 according to embodiments provided herein. [Figure 7] 2 shows a simplified schematic diagram of various arrangements of optical components that can be used in the robotic arm alignment device of FIG. 1 according to embodiments provided herein. [Figure 8] 2 shows a simplified schematic diagram of various arrangements of optical components that can be used in the robotic arm alignment device of FIG. 1 according to embodiments provided herein. [Figure 9] 9 illustrates an image that can be captured by the optical component arrangement of FIG. 8 according to embodiments provided herein. [Figure 10] 10A and 10B show top and left side views, respectively, of a positioning tool according to embodiments provided herein. [Figure 11] 1 illustrates a top view of another positioning tool according to embodiments provided herein. [Figure 12] 10A-10C show images of a positioning tool having different back panels, respectively, according to embodiments provided herein. [Figure 13] 10A-10C show images of a positioning tool having different back panels, respectively, according to embodiments provided herein. [Figure 14] 10A-10C show images of a positioning tool having different back panels, respectively, according to embodiments provided herein. [Figure 15] 15A, 15B, and 15C show images captured from different angles, respectively, of a positioning tool held by a robotic arm according to embodiments provided herein. [Figure 16] 1 shows a simplified side schematic view of a positioning tool and two cameras according to embodiments provided herein. [Figure 17] 1 shows a flowchart of a method for aligning a robotic arm in an automated sample analysis system according to embodiments provided herein. [Figure 18]1 shows an image of a robotic arm and a sample tube carrier each having reference markers thereon, according to embodiments provided herein. DETAILED DESCRIPTION OF THE INVENTION

[0012] The embodiments described herein provide apparatus and methods for aligning a robotic arm with a sample tube carrier in an automated sample analysis system so that sample tubes (i.e., biological liquid containers, e.g., test tubes, vials, etc.) carried by the robotic arm can be placed with high precision at predetermined points on the sample tube carrier in and through the automated sample analysis system, e.g., for inspection (quality check), analysis, and / or transport.

[0013] According to one or more embodiments, an optically-based approach is used to align the robotic arm. Multiple optical components (e.g., two or more cameras or only one camera and one or more mirrors and / or prisms) can be positioned at a designated location in the automated sample analysis system (e.g., a central location in the system) where a sample tube is expected to be received by a sample tube carrier. A first reference marker can be "attached" to or relative to the sample tube carrier, and a second reference marker can be "attached" to or relative to the robotic arm.

[0014] That is, the first reference marker may be a physical marker (e.g., a point light source or a sticker having a distinguishable shape and / or color) that can be affixed to the sample tube carrier or to a structure referenced to the sample tube carrier that is distinguishable in images captured by the multiple optical components. Alternatively, the first reference marker may be a selected location on the sample tube carrier or on a structure referenced to the sample tube carrier that is distinguishable in images captured by the multiple optical components by a change in geometric shape or color contrast at the selected location.

[0015] Similarly, the second reference marker may be a physical marker (e.g., a point light source or a sticker having a distinguishable shape and / or color) that can be affixed to the robot arm or to a structure relative to the robot arm that is distinguishable in images captured by the multiple optical components. Alternatively, the second reference marker may be a selected location on the robot arm or to a structure relative to the robot arm that is distinguishable in images captured by the multiple optical components by a change in geometric shape or color contrast at the selected location.

[0016] In some embodiments, a uniquely designed positioning tool configured to be held by the sample tube carrier and by the robotic arm can include first and second reference markers. The first and second reference markers are configured to be locatable and trackable using multiple optical components and a three-dimensional (3D) coordinate system. To accurately place the sample tube at a predetermined point on the sample tube carrier, a system-determined 3D offset between the coordinates of the first and second reference markers can be used to guide the movement of the robotic arm and / or the movement of the sample tube carrier mounted on a movable track to align the robotic arm with the sample tube carrier.

[0017] Advantageously, the optical-based approach can provide increased accuracy and reliability compared to known alignment methods that rely on trial-and-error mechanical techniques employing collision sensor feedback to regulate the movement of a robot arm as it attempts to insert a workpiece held by the robot arm into a circular hole structure. The optical-based approach is a non-contact system that directly estimates the relative coordinate difference between the robot arm and the sample tube carrier. This avoids reliance on the mechanical tolerances of the associated hardware components and the degradation and replacement of mechanical members due to repeated mechanical collisions.

[0018] According to one or more embodiments, provided herein are apparatus and methods for aligning a robotic arm with a sample tube carrier in an automated sample analysis system using an optically based approach, as described in further detail below in connection with Figures 1-18.

[0019] FIG. 1 illustrates a robotic arm positioning apparatus 100 according to one or more embodiments. The robotic arm positioning apparatus 100 includes a robot 102, a sample tube carrier 104, a controller 106, and multiple optical components 108. The robot 102 can be used in an automated sample analysis system, which can include one or more diagnostic machines, clinical analyzers, centrifuges, or other processing or testing machines or stations. The robot 102 includes a robotic arm 103 configured to hold a sample tube 110 (shown in phantom) and move it in three dimensions (e.g., X, Y, and Z, where Z is perpendicular to the plane of the page as shown in FIG. 1). The robotic arm 103 can move the sample tube 110 from a first location (e.g., a staging location) to a second location (e.g., an inspection location, a testing location, or a processing location). In some embodiments, the robot 102 can include a rotational motor 102R, which can be configured to rotate the robot arm 103 in a desired angular direction in a rotational direction θ (i.e., a combination of the X and Z directions). The robot 102 can also include a vertical motor 102V, which can be configured to move the upright 102U vertically (e.g., along the ±Y directions as shown). In some embodiments, the robot arm 103 can include a first member 103A, a second member 103B, and a gripper 103G. The robot 102 can further include a translational motor 102T, which can be configured to move the second member 103B and the gripper 103G horizontally (e.g., along the ±X directions as shown). Other suitable robot motors and mechanisms for providing 3D motion (e.g., X, Y, θ motion; X, Y, Z motion; or other combinations of motion) can be provided. Suitable feedback mechanisms may be provided as to the extent of each movement, such as by position and / or rotational encoders (not shown).Thus, the robot coordinate system can include X, Y, θ, or X, Y, Z, or any subset or combination thereof.

[0020] The gripper 103G can be configured to grasp an object, such as a sample tube, and can include two or more gripper fingers 103F1 and 103F2, which can be opposed to one another and movable relative to one another. The gripper fingers 103F1 and 103F2 can be driven to open and close by an actuation mechanism 103M, which can be an electric, pneumatic, or hydraulic servomotor. Other suitable mechanisms for initiating the gripping action of the gripper fingers 103F1 and 103F2 can be used. The gripper 103G can also include a gripper rotation motor 103R configured to rotate the gripper 103G, and more specifically, the gripper fingers 103F1 and 103F2, about a gripper rotation axis 103X to rotationally orient the gripper fingers 103F1 and 103F2 with high precision as needed. A rotational encoder (not shown) may be included to provide feedback regarding the direction of rotation of gripper fingers 103F1 and 103F2 to controller 106. Other types of grippers may also be used.

[0021] The robot 102 can be configured to move sample tubes 110 into and out of a sample tube carrier 104. The sample tube carrier 104 can include a sample tube receptacle 104R disposed in a sample tube carrier base 104B. The sample tube carrier 104 can be mounted on a movable track 112, which can be configured to transport the sample tubes to various locations within the automated sample analysis system.

[0022] The controller 106 can include a microprocessor, processing circuitry (including A / D converters, amplifiers, filters, etc.), memory, drive circuitry, and feedback circuitry configured and operable to control the manner in which the robot 102 and its various components (e.g., rotational motor 102R, translational motor 102T, vertical motor 102V, actuation mechanism 103M, and gripper rotation motor 103R) operate. The controller 106 can also be configured and operable to control the manner in which the optical component 108 operates and process inputs from the optical component 108 and various encoders and sensors (not shown). In some embodiments, the controller 106 can include a machine learning algorithm trained to identify the first and second reference markers in images received from the optical component 108.

[0023] The optical component 108, in some embodiments, can include two cameras 108C1 and 108C2, positioned around a central point 101 of the system for capturing images of a first reference marker (on or relative to the sample tube carrier 104) and a second reference marker (on or relative to the robotic arm 103) at various angles. The cameras 108C1 and 108C2 can be any suitable device for capturing clear digital images, such as, for example, a conventional digital camera capable of capturing pixelated images, a charge-coupled device (CCD), a photodetector array, one or more CMOS sensors, etc. The controller 106 processes the images received from the cameras 108C1 and 108C2 to determine the 3D position coordinates of the respective first and second reference markers, and can then align the robot arm 103 with the sample tube carrier 104 based on the 3D offset between those position coordinates, so that the sample tube 110 can be positioned with high precision and lifted from the sample tube carrier 104 by the robot arm 103, as described in more detail below. Other embodiments can have more or less than two cameras and / or other optical component arrangements that can be used in the robot arm alignment apparatus 100, as described below in connection with FIGS. 2-8.

[0024] 2 illustrates an optical components mechanism 208 that can be used in the robotic arm positioning apparatus 100 according to one or more embodiments. The optical components mechanism 208 includes three cameras 208C1, 208C2, and 208C3, which may be spaced approximately equally spaced (e.g., about 120 degrees apart) from one another around a central point 201 of the system for receiving sample tube receptacles 104R of sample tube carriers 104 mounted on the movable track 112. The sample tube receptacles 104R are accessible by the robot 102 (not shown in FIG. 2). The manner in which the cameras 208C1, 208C2, and 208C3 operate can be controlled by the controller 106, which can also receive and process images from the cameras 208C1, 208C2, and 208C3.

[0025] The optical component assembly 208 can also include back panels 214A, 214B, and 214C, which are positioned opposite cameras 208C1, 208C2, and 208C3, respectively, with the sample tube receptacle 104R located between each pair of cameras and the back panel. In some embodiments, one or more of the back panels 214A, 214B, and 214C can be active lighting panels (e.g., white light sources) controlled by the controller 106. In some embodiments, one or more of the back panels 214A, 214B, and 214C can be passive reflective panels or simply dark or black background panels with front lighting. In other embodiments, the back panels 214A, 214B, and 214C can provide other suitable types of background or backlighting.

[0026] In some embodiments, the optical component assembly 208 can include a housing 216 that can at least partially enclose or cover the sample tube carrier 104 to minimize the influence of external light sources. The housing 216 can include one or more doors 216D to allow the sample tube carrier 104 to enter and exit the housing 216 via the movable track 112. In some embodiments, a ceiling (not shown) of the housing 216 can include an opening to provide access to the sample tube carrier 104 by the robot 102.

[0027] The optical component mechanism 208 can be used to capture three images (each from a different angle) of a first reference marker on or referenced to the sample tube carrier 104 and a second reference marker on or referenced to the robot arm 103 via cameras 208C1, 208C2, and 208C3.

[0028] 3-8 illustrate other optical component arrangements that can be used in the robot arm alignment apparatus 100 according to one or more embodiments. For example, instead of using multiple cameras as shown in FIG. 3, the optical component arrangement 308 can include only one camera 308C and a mirror 308M that can be used to capture two images (each from a different angle) of one or more markers attached to the object 308J. Similarly, FIG. 4 illustrates an optical component arrangement 408 that can also include only one camera 408C and a bi-fold mirror 408M that can be used to capture two images (each from a different angle) of one or more markers attached to the object 408J. FIG. 5 illustrates an optical component arrangement 508 that can include only one camera 508C and two mirrors 508M1 and 508M2 that can be used to capture two images (each from a different angle) of one or more markers attached to the object 508J. Figure 6 illustrates optical components assembly 608, which may include a sole camera 608C and an arrangement of four mirrors 608M1, 608M2, 608M3, and 608M4, that may be used to capture two images (each from a different angle) of one or more markers attached to object 608J. Figure 7 illustrates optical components assembly 708, which may include a sole camera 708C and an arrangement of three mirrors 708M1, 708M2, and 708M3, that may be used to capture two images (each from a different angle) of one or more markers attached to object 708J. Additionally, Figure 8 illustrates optical components assembly 808, which may include a prism 808P and a sole camera 808C, that may be used to capture a pair of sub-images (each from a different angle) of object 808J. Specifically, a light beam entering prism 808P splits and enters lens 808L of camera 808C, creating two images 818-L and 818-R (each from a different angle) on sensor plane 808S of camera 808C.Light rays represented by rays P2-2 and P1-2 create image 818-L, and light rays represented by rays P1-1 and P2-1 create image 818-R. As further shown, FIG. 9 shows left image 918-L and right image 918-R captured by camera 808C, each created at a different angle by prism 808P. Without prism 808P, two cameras would be required to capture left image 918-L and right image 918-R (one positioned to the left of camera 808C and one positioned to the right of camera 808C). Other optical component arrangements are possible, using one or more cameras, one or more mirrors, and / or one or more prisms.

[0029] In some embodiments, the robot arm alignment device 100 can also include a positioning tool 1000 shown in FIGS. 10A and 10B. The positioning tool 1000 can have a cylindrical structure similar to a sample tube (e.g., sample tube 110), which can be held and moved by a robot arm gripper (e.g., robot arm gripper 103G) and received in and held by a sample tube carrier (e.g., sample tube carrier 104). The positioning tool 1000 can have multiple sections S1, S2, S3, S4, and S5, each of which can have a different geometry (e.g., different length and / or diameter) from adjacent sections. For example, sections S2 and S4 can each have a diameter D2 that is smaller than the diameter D1 of sections S1, S3, and S5; in some embodiments, diameter D1 can be approximately 16 mm (±0.25 mm) and diameter D2 can be approximately 12 mm (±0.25 mm). In some embodiments, the positioning tool 1000 can have a total length L of about 110 mm (±0.5 mm). Sections S1 and S4 can each have a respective length L1 and L4 of about 5.0 mm (±0.5 mm), and section S5 can have a length L5 of about 32.5 mm (±0.5 mm). Other suitable numbers of sections and dimensions of the positioning tool 1000 are possible.

[0030] The positioning tool 1000 may have a first reference marker and a second reference marker “attached” to it (e.g., identified thereon). The first reference marker 1020 (represented by an “X” in FIG. 10A ) may be at the center point of the intersection of sections S2 and S3 where a change in geometry occurs. The first reference marker 1020 may be located a length L345 from the bottom of the positioning tool 1000, which length L345 is approximately 70.0 mm (±0.5 mm) in some embodiments. The first reference marker 1020 may be used when the positioning tool 1000 is received in and held by a sample tube carrier, such as sample tube carrier 104, to establish a target position in the sample tube carrier. The second reference marker 1022 (also represented by an “X” in FIG. 10A ) may be at the center point of the intersection of sections S4 and S5 where a change in geometry occurs. The second reference marker 1022 may be located at a length L5 from the bottom of the positioning tool 1000. The second reference marker 1022 can be used when the positioning tool 1000 is held by the robot arm 103 (and gripper 103G) to align the position of the robot arm 103 with respect to the target position. Other suitable locations for the first and second reference markers 1020 and 1022 on the positioning tool 1000 may be possible. In some embodiments, a single reference marker (e.g., reference marker 1022) can be used if it is visible (i.e., can be imaged by optical components) when the positioning tool 1000 is held by the sample tube carrier and by the robot arm 103. In such embodiments, the positioning tool 1000 can have fewer changes in the geometry of the sections.

[0031] In addition to or instead of using changes in the geometry of sections on the positioning tool to identify the first and second reference markers, in some embodiments, changes in color contrast on the positioning tool can be used to identify the first and second reference markers, as shown in FIG. 11.

[0032] FIG. 11 illustrates a positioning tool 1100 that can be used in the robotic arm alignment apparatus 100 according to one or more embodiments. The positioning tool 1100 can also have a cylindrical structure similar to a sample tube (e.g., sample tube 110), which can be held and moved by a robotic arm gripper (e.g., robotic arm gripper 103G) and received in and held by a sample tube carrier (e.g., sample tube carrier 104). The positioning tool 1100 can have multiple sections S1′, S2′, S3′, S4′, and S5′, each of which can have a different color contrast (e.g., black or white) from adjacent sections. “Stickering” (i.e., affixing bright white and / or black stickers) can be used to create color contrast in the positioning tool 1100. In some embodiments, the positioning tool 1100 can be constructed to have the same number and dimensions of sections as the positioning tool 1000, if desired. In other embodiments, by relying solely on changes in color contrast to distinguish between the first and second reference markers, the positioning tool 1100 may have other section configurations or may not include any sections with various geometric shapes.

[0033] The positioning tool 1100 may have a first reference marker 1120 and a second reference marker 1122 "attached" to (e.g., identified on) it. The first reference marker 1120 (represented in FIG. 11 by a black / white "X") may be at the center point of the intersection of sections S2' and S3', where both the change in color contrast and the change in geometry occur. In some embodiments, the first reference marker 1120 may be located a length from the bottom of the positioning tool 1100 equal to or substantially equal to the length L345 of the positioning tool 1000. The first reference marker 1120 may be used when the positioning tool 1100 is received in and held by a sample tube carrier, such as sample tube carrier 104, to establish a target position in the sample tube carrier. A second reference marker 1122 (also represented in FIG. 11 by a black / white "X") may be located at the center point of the intersection of sections S3' and S4', where both the change in color contrast and the change in geometry occur. In some embodiments, the second reference marker 1122 may be located a length from the bottom of the positioning tool 1100 equal to or substantially equal to the length L5 of the positioning tool 1100. The second reference marker 1122 may be used when the positioning tool 1100 is held by the robot arm 103 (and gripper 103G) to align the position of the robot arm 103 with respect to the target position. Other suitable locations for the first and second reference markers 1120 and 1122 on the positioning tool 1100 may be possible. In some embodiments, a single reference marker (e.g., reference marker 1122) can be used if it is visible (i.e., can be imaged by optical components) when the positioning tool 1100 is held on the sample tube carrier and by the robotic arm 103. In such embodiments, the positioning tool 1100 can have less variation in color contrast and section geometry.

[0034] The positioning tool 1100, which has both changes in the geometry of the sections and changes in the color contrast, can be advantageously used to identify the first and second reference markers 1120 and 1122 by changes in the geometry of the sections (like the positioning tool 1000) or changes in the color contrast, or both.

[0035] In an alternative embodiment, the bottom tip point of the positioning tool (e.g., bottom tip point 1024 of positioning tool 1000 and / or bottom tip point 1124 of positioning tool 1100) can be used in place of second reference marker 1022 and / or 1122 if the bottom tip point is visible to all cameras in the optical component mechanism of the robot arm alignment device 100 when the positioning tool is held by the robot arm gripper (e.g., robot arm gripper 103G, etc.).

[0036] Positioning tools 1000 and 1100 are each advantageously configured to work with multiple back panel setups (e.g., actively illuminated back panels, passive reflective back panels, or simply dark background back panels with or without front lighting), as shown in Figures 12-14.

[0037] 12 shows an image 1200 of the positioning tool 1100 being received in the sample tube receptacle 1204R, captured using a camera of an optical component assembly (such as optical component assembly 108 or 208) using a dark background back panel 1214, in accordance with one or more embodiments. Alternatively, the positioning tool 1000 can be used with a dark background back panel 1214. As shown, the first reference marker 1220 is identifiable in the image 1200 by a change in color contrast or a change in the geometry of the section.

[0038] 13 shows an image 1300 of the positioning tool 1100 being received in a sample tube receptacle 1304R, captured using a camera of an optical component assembly (such as optical component assembly 108 or 208) using a passive reflective back panel 1314, according to one or more embodiments. Alternatively, the positioning tool 1000 can be used with a passive reflective back panel 1314. As shown, a first reference marker 1320 is identifiable in the image 1300 by a change in color contrast or a change in section geometry.

[0039] 14 shows an image 1400 of the positioning tool 1100 received in a sample tube receptacle 1404R, captured using a camera of an optical component assembly (e.g., optical component assembly 108 or 208) using an active illumination (e.g., white light source) back panel 1414, according to one or more embodiments. Alternatively, the positioning tool 1000 can be used with the active illumination back panel 1414. As shown, the first reference marker 1420 is identifiable in the image 1400 due to the change in section geometry. Note that positioning tools without changes in section geometry should not be used with the active illumination back panel 1414, as images captured using the active illumination back panel 1414 may degrade the color contrast changes on the positioning tool due to the active illumination.

[0040] In some embodiments, the alignment of the robot arm performed by the robot arm alignment device 100 of FIG. 1 can include loading a positioning tool (e.g., positioning tool 1000 or 1100) onto the sample tube carrier 104. While misalignment may prevent the robot 102 from loading with high precision, the positioning tool can be loaded onto the sample tube carrier 104 either manually by an operator or automatically by the robot 102. The sample tube carrier 104 is positioned or moved to a central location within the field of view of the optical components, such as the central location 101 of the system in FIG. 1 or the central location 201 of the system in FIG. 2. The optical components 108 (or one of 208, 308, 408, 508, 608, 708, and 808) can capture multiple images of the positioning tool held on the sample tube carrier 104, each from a different angle. The multiple images can be processed by the controller 106 to identify a first reference marker (e.g., first reference marker 1020, 1120, 1220, 1320, or 1420) by detecting changes in the geometry or color contrast of a section on the positioning tool. The controller 106 can then perform triangulation (using any suitable known method) to determine the 3D location of the first reference marker (represented by 3D coordinates in the optical component coordinate system). The determined 3D coordinates of the first reference marker can be used as a target position to which the robot arm 103 is to be aligned.

[0041] Alignment of the robot arm can continue by having the robot arm 103 hold a positioning tool. The positioning tool can be picked up at a storage location by the robot 102 or manually coupled to the gripper 103G by an operator. The controller 106 can move the robot arm 103 to a target location, and the optical component 108 (or one of 208, 308, 408, 508, 608, 708, and 808) can capture multiple images of the positioning tool held by the robot arm 103, each from a different angle. For example, FIGS. 15A, 15B, and 15C show multiple images, which can be captured by the optical component assembly 208 of FIG. 2. Image 1500A can be captured by camera 208C1, image 1500B can be captured by camera 208C3, and image 1500C can be captured by camera 208C2. Each image captured at a different angle shows the positioning tool 1100 being held by the robot arm with gripper 1503G. Images 1500A, 1500B, and 1500C can be processed by the controller 106. The controller 106 can identify the location of second reference marker 1522A in image 1500A, second reference marker 1522B in image 1500B, and second reference marker 1522C in image 1500C. The controller 106 can then perform triangulation (again using any suitable known method) to determine the 3D coordinate of the second reference marker in the optical component coordinate system. The controller 106 can then determine the 3D offset between the coordinates of the first and second reference markers. If the 3D offset exceeds a predetermined deviation, the robot arm 103 can be considered misaligned with the sample tube carrier 104 at the system center location 201 (i.e., the target location).

[0042] The controller 106 can then cause the robot arm 103 to move the positioning tool 1100 to a new location based on the determined 3D offset deviation. For example, if the determined 3D offset exceeds a predetermined deviation of +2 mm in the X direction, −3 mm in the Y direction, and −1 mm in the Z direction, the controller 106 can cause the robot arm to move the positioning tool 1100 −2 mm in the X direction, +3 mm in the Y direction, and +1 mm in the Z direction. Note that in some embodiments, if the robot arm may not be able to translate in one of the X, Y, and Z directions, the controller 106 can further calculate an equivalent amount of angular rotational movement of the robot arm (e.g., along ±angular direction θ as shown in FIG. 1 ) based on the determined X, Y, and Z coordinate deviation. In some embodiments, the controller 106 can additionally or alternatively cause the movable track 112 to move the sample tube carrier 104 as needed based on the determined 3D offset deviation and the movement capabilities of the robot arm.

[0043] At the new position of the robotic arm 103 and / or sample tube carrier 104, images are again captured and processed and a new 3D offset is determined. The process can continue iteratively until the robotic arm is considered aligned with the sample tube carrier, at which point the 3D offset does not exceed a predetermined deviation.

[0044] Note that the triangulation process may result in a slight height deviation from the true center point of the reference marker on the positioning tool. This deviation occurs by locating the reference marker on the surface of the positioning tool at a distance R from the true center, where R is the radius of the section to which the reference marker is attached. FIG. 16 illustrates the height deviation that may occur in a second reference marker 1622 imaged by a two-camera optical component setup. As shown, an image of the positioning tool 1100 (only the lower portion is shown) by camera 1608C1 can capture second reference marker 1622A, and an image of the positioning tool 1100 from a different angle can capture second reference marker 1622B. The second reference marker 1622 may be a true center point having a height H′ measured from the optical center 1626 of camera 1608C1 (the optical center of camera 1608C2 can also be used as a reference point). However, triangulation of the second reference marker 1622 by the controller 106 based on the images captured by the cameras 1608C1 and 1608C2 may result in a 3D coordinate for the triangulated second reference marker 1622T, which has a height H measured from the optical center 1626 of the cameras 1608C1 and 1608C2. In some embodiments, the controller 106 may be configured to correct for that height deviation by calculating:

[0045] H'=H×(DR) / D

[0046] where D is the distance between the second triangulation reference marker 1622T and the optical center 1626 along the line of sight 1628 of the camera.

[0047] FIG. 17 illustrates a method 1700 for aligning a robotic arm in an automated sample analysis system, according to one or more embodiments. At operational block 1702, method 1700 can begin by identifying a location of a first marker relative to the sample tube carrier. For example, the location of the first marker can be first reference marker 1020 at the intersection of sections S2 and S3, as shown in FIG. 10A, or first reference marker 1120 at the intersection of sections S2' and S3', as shown in FIG. 11. Alternatively, the location of the first marker can be identified directly on the sample tube carrier 1804, as shown in image 1800 of FIG. 18, by applying a point light source or white sticker to the sample tube carrier 1804, which creates a first reference marker 1820, according to one or more embodiments.

[0048] At operational block 1704, method 1700 may include identifying a location of a second marker relative to the robot arm. For example, the location of the second marker may be second reference marker 1022 at the intersection of sections S4 and S5 as shown in Figure 10A, or second reference marker 1122 at the intersection of sections S3' and S4' as shown in Figure 11. Alternatively, the location of the second marker may be identified directly on gripper 1803G of robot arm 1803 as shown in image 1800 of Figure 18 by applying a point light source or white sticker to gripper 1803G that creates second reference marker 1822, according to one or more embodiments.

[0049] At process block 1706, method 1700 may include determining coordinates of the location of the first marker using a plurality of optical components and a controller, and at process block 1708, method 1700 may include determining coordinates of the location of the second marker using a plurality of optical components and a controller. For example, as shown in FIG. 1, optical components 108 and controller 106 of robotic arm alignment device 100 may be used to capture and process a plurality of images of each of the first and second marker locations to determine their respective coordinates in the optical component coordinate system.

[0050] At process block 1710, the method 1700 may include adjusting the position of the robotic arm and / or the sample tube carrier via the controller in response to the coordinates of the location of the second marker exceeding a predetermined deviation from the coordinates of the location of the first marker.

[0051] In some embodiments, method 1700 may further include a process block (not shown) that includes providing a positioning tool configured to be held by the robotic arm and on the sample tube carrier, the positioning tool including sections having different geometric shapes or color contrasts, and the locations of the first and second markers are respectively identified at respective points on the positioning tool where a change in geometry or change in color contrast occurs.

[0052] While the disclosure is susceptible to various modifications and alternative forms, specific method and apparatus embodiments have been shown by way of example in the drawings and are herein described in detail. It should be understood, however, that the specific methods and apparatus disclosed herein do not limit the scope of the disclosure or the claims that follow.

Claims

1. 1. An apparatus for aligning a robotic arm in an automated sample analysis system, comprising: a robotic arm configured to hold and move a sample tube; a sample tube carrier configured to hold a sample tube; a positioning tool configured to be held by the robotic arm, moved by the robotic arm, and held by the sample tube carrier; a plurality of optical components; a controller operably connected to the robotic arm and the plurality of optical components, the controller comprising: processing images received from the plurality of optical components of a positioning tool held on the sample tube carrier to determine coordinates of a first point on the positioning tool; processing images received from the plurality of optical components of a positioning tool held by the robotic arm to determine coordinates of a second point on the positioning tool; In response to the coordinates of the second point exceeding a predetermined deviation from the coordinates of the first point, causing a movement of a positioning tool held by the robotic arm or held on the sample tube carrier. The device is operable to:

2. The apparatus of claim 1 , wherein the plurality of optical components comprises a plurality of cameras.

3. The apparatus of claim 1 , wherein the plurality of optical components includes one or more prisms or mirrors and a single camera.

4. The apparatus of claim 1 , wherein the positioning tool is cylindrical and includes sections with different geometric shapes or color contrasts.

5. The apparatus of claim 4 , wherein the first point or the second point on the positioning tool is at an intersection of two sections where a change in geometry or a change in color contrast occurs.

6. The apparatus of claim 1 , wherein the first point and the second point on the positioning tool are the same point.

7. 1. An apparatus for aligning a robotic arm, comprising: a sample tube carrier configured to hold a sample tube and having a first marker thereon; a robotic arm configured to hold and move the sample tube, the robotic arm including a gripper having a second marker thereon; a plurality of optical components; a controller operably connected to the robotic arm and the plurality of optical components, the controller comprising: processing images of the sample tube carrier received from the plurality of optical components to determine coordinates of the first marker; processing images of the gripper received from the plurality of optical components to determine coordinates of the second marker; In response to the coordinates of the second marker exceeding a predetermined deviation from the coordinates of the first marker, causing movement of the gripper via the robotic arm or movement of the sample tube carrier via the movable track. The device is operable to:

8. 8. The apparatus of claim 7, wherein the first marker is a physical item attached to the sample tube carrier or the second marker is a physical item attached to the gripper.

9. The apparatus of claim 8 , wherein the physical item is a point light source or a sticker.

10. 8. The apparatus of claim 7, wherein the first marker is located at a point on the gripper where a change in geometry or a change in color contrast occurs, or the second marker is located at a point on the sample tube carrier where a change in geometry or a change in color contrast occurs.

11. 1. A method of aligning a robotic arm in an automated sample analysis system, comprising: Identifying a location of a first marker relative to the sample tube carrier; Identifying a location of the second marker relative to the robot arm; determining coordinates of a location of a first marker using a plurality of optical components and a controller; determining coordinates of a location of a second marker using a plurality of optical components and a controller; adjusting the position of the robotic arm or sample tube carrier via the controller in response to the coordinates of the location of the second marker exceeding a predetermined deviation from the coordinates of the location of the first marker; The method comprising:

12. The method of claim 11 , wherein the plurality of optical components comprises a plurality of cameras.

13. The method of claim 11 , wherein the plurality of optical components includes a camera and one or more prisms or mirrors.

14. The method of claim 11 , wherein identifying the location of the first marker comprises identifying the location of the first marker on a positioning tool held by the sample tube carrier.

15. 15. The method of claim 14, wherein identifying the location of the first marker comprises identifying the location of the first marker at a point on a positioning tool held in the sample tube carrier, where the positioning tool has a change in geometric shape or color contrast.

16. The method of claim 11 , wherein identifying the location of the second marker comprises identifying the location of the second marker on a positioning tool held by a robotic arm.

17. 17. The method of claim 16, wherein identifying the location of the second marker comprises identifying the location of the second marker at a point on a positioning tool held by the robotic arm, where the positioning tool has a change in geometric shape or color contrast.

18. 12. The method of claim 11, further comprising providing a positioning tool configured to be held by the robotic arm and to the sample tube carrier, the positioning tool including sections having different geometric shapes or color contrasts.

19. The method of claim 11 , wherein identifying the location of the first marker comprises identifying the location of the first marker on a sample tube carrier.

20. The method of claim 11 , wherein identifying a location of the second marker includes identifying a location of the second marker on a robotic arm.

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