Double-sided target and method for non-contact determination of three-dimensional spatial coordinates

Abstract

A spatial coordinate measurement tool for identifying a three-dimensional spatial position. The spatial coordinate measurement tool includes a portable body having an optical target on an exterior surface including at least one target element observable by a camera system. A non-contact distance sensor is secured to the body, having a sensor measurement axis in a determinable relationship to the optical target. The non-contact distance sensor is configured to acquire a measure of distance from the sensor to a point on a surface intersected by the measurement axis, with the resulting measurement either displayed to an operator or communicated wirelessly to a vehicle measurement or inspection system.

Description

DOUBLE-SIDED TARGET AND METHOD FOR NON-CONTACTDETERMINATION OF THREE-DIMENSIONAL SPATIAL COORDINATESCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] The present application is related to, and claims priority from, both US Provisional Patent Application Serial No. 63 / 687,945 filed on August 28, 2024 and US Provisional Patent Application Serial No. 63 / 804,221 filed on May 12, 2025, each of which is herein incorporated by reference.STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH

[0002] Not Applicable.BACKGROUND

[0003] The present invention is directed towards a system and method for determining three-dimensional spatial coordinates of locations associated with a vehicle undergoing a service or inspection procedure, such as vehicle measurement and / or sensor calibration procedures, and in particular, to a combination of a distance measurement sensor and an multi-faceted optical target configured for non-contact determination of three-dimensional spatial coordinates of a selected point or location.

[0004] During vehicle inspection or service procedures, such as wheel alignment measurement or the calibration of a vehicle Automated Driver Assistance System (ADAS) sensor, accurate identification of points or locations within a spatial frame of reference encompassing the vehicle may be required. These points or locations may be used to establish references against which measurements are taken, or for guiding the placement of various calibration fixtures or sensor targets. In many situations, these points or locations correspond to features on a vehicle body surface or on an40812179.V1 1adjacent floor surface, and may lack any inherent distinguishing features which can be directly observed by a traditional camera-based measurement system.

[0005] One solution employed by the automotive service industry is to utilize an optical target affixed in a known relationship to a pointer or reference stick having predetermined dimensions. With a distal tip of the pointer positioned to contact the point or location to be measured, an image of the affixed optical target is captured by an observing camera system. The resulting image is processed to identify the spatial position and orientation of the affixed optical target within the camera’s frame of reference. An offset corresponding to the known relationship between the affixed optical target and the pointer or reference stick is applied to identify the spatial coordinates of the location contacted by the distal tip in the camera’s frame of reference.

[0006] For example, United States Patent No. 6,658,751 to Jackson et al. discloses a target system for determining the location of a position on a vehicle using a target body, one or more target elements, a trigger, and a point definer. The point definer comprises an arm extending from the target body, terminating at a distal end in a known location relative to the target body. With the distal end held adjacent to a position on a vehicle body, a position determination system responsive to the trigger acquires images of the target elements while the target body is positioned in at least three different locations. Using acquired images, the position determination system establishes the location of the distal end within a three-dimensional frame of reference. Similarly, United States Patent No. 6,796,043 to Jackson et al. refines the point definer to include one or more joints in the extended arm, and establishes the location of the distal end at a position on a vehicle body from a single image. United States Patent No. 11 ,993,282 to Rogers et al. defines a “tip target” having a target body and a point40812179.V1 2definer extending from the target body to a distal end at a known angular orientation and location from the target body. The target body is observed by cameras of a vehicle ADAS calibration system to measure the pose of the tip target in a camera coordinate system, from which the system calculates the location of the distal end in the camera coordinate system, and thereby the location of any point on a floor surface or vehicle body contacted by the distal end. PCT International Patent Application Publication WO 98 / 48241 to Krypton Electronic Engineering describes a device and method for determining a position of a selected point using a measuring pointer affixed to a holder having a set of observable reference points. By observing the position of the reference points as the holder is rotated to various positions with the measuring pointer in contact with the selected point, the relative position of the measuring point (and selected point) are calculated.

[0007] Conventional target pointers have multiple drawbacks which limit their use in the automotive service industry. First, these target pointers require that the pointing tip be placed in physical contact with the location to be measured. Depending upon the length or configuration of the target pointer, some vehicle surfaces, such as inside a wheel well, may be impossible to reach without interference between the optical target portion of the target pointer and the vehicle body. Second, once in physical contact with the location to be measured, the optical target portion of the conventional target pointer must be visible to an observing camera system. If the camera system is located at the front of a vehicle within a service bay, and the location to be measured is located behind or beneath the vehicle, it may not be possible to position the target pointer to contact the measurement location while the optical target remains visible to the observing camera. This problem can be solved by providing interchangeable pointer arms of varying lengths, but this solution is often impractical in a vehicle service40812179.V1 3environment due to the time needed to change out pointer arms between measurements, as well as the need for recalibration.

[0008] Accordingly, it would be beneficial to provide a target pointer system which does not need to be in physical contact with a point or location to be identified, allowing an associated optical target to remain within a camera field of view even when determining the location of selected points or locations occluded by the vehicle or other structures within a vehicle service area.

[0009] It would be further beneficial to provide the target pointer system with target elements visible from opposite lateral sides to facilitate repositioning of the target pointer system around a vehicle undergoing inspection while remaining visible to a fixed camera system.BRIEF SUMMARY

[0010] Briefly stated, the present disclosure sets forth a spatial coordinate measurement (SCM) tool for identifying a three-dimensional spatial position. The SCM tool includes a body having a surface supporting an optical target including at least one target element observable by a camera system. One or more distance sensors are secured to the body such that a measurement axis of each distance sensor is in a known or determinable relationship to the optical target. Each distance sensor is configured to acquire a measure of a distance from the distance sensor to a point on a surface intersected by an associated measurement axis. The resulting distance measurement is either displayed to an operator at the distance sensor or communicated to a processing system. The processing system is configured with software instructions to evaluate an image of the optical target acquired by the camera system, the measured distance(s) which are received from the distance sensor or input by an operator, and the relationship of the distance sensor’s measurement axis40812179.V1 4to the optical target, to determine a spatial location for each intersection point within a spatial reference frame.

[0011] In a variation of the present disclosure the SCM tool includes a laterally symmetric body having at least one pair of target surfaces supporting optical targets, each optical target including at least one target element observable by a camera system. A first target surface of the pair is oriented relative to a first lateral side of the SCM tool, while a second target surface of the pair is oriented relative to an opposite lateral side of the SCM tool. A distance sensor is secured to the body such that a measurement axis of the distance sensor is in a known or determinable relationship to the optical targets. The distance sensor is configured to acquire a measure of distance from the distance sensor to an intersection point on a surface intersected by an associated measurement axis. The resulting distance measurement is either displayed to an operator at the distance sensor or communicated to a processing system. The processing system is configured with software instructions to evaluate an image of an optical target on the SCM tool acquired by the camera system, the measured distance received from the distance sensor or input by an operator, and the known relationship of the distance sensor’s measurement axis to the optical target(s), to determine a spatial location for the intersection point within a spatial reference frame.

[0012] In a further variation the SCM tool includes two pairs of target surfaces supporting optical targets. Each pair of target surfaces include a first target surface oriented relative to a first lateral side of the SCM tool and a second target surface oriented relative to an opposite lateral side of the SCM tool.

[0013] In one embodiment the distance sensor is a non-contact optical time-of-flight distance sensor or a laser range finder.40812179.V1 5

[0014] In a further embodiment the distance sensor is removable from the SCM tool for independent use by an operator.

[0015] In one embodiment the distance sensor is a tape measure or other mechanically extendable and retractable distance measurement tool configured to provide a measure of distance along an axis in a known or determinable relationship to the optical target.

[0016] In a further embodiment, the portably body is configured for temporary coupling to a support stand.

[0017] In another variant, the present disclosure sets forth a spatial coordinate measurement (SCM) tool for identifying a three-dimensional spatial position. The SCM tool includes a body with a surface supporting a camera having a field of view. The camera is configured to observe a optical target including at least one target element located at a known or determined position and orientation within a frame of reference. At least one non-contact distance sensor is secured to the body such that a measurement axis of each distance sensor is held in a determinable relationship to an optical axis of the camera. Each distance sensor is configured to acquire a measure of distance from the distance sensor to a point on a surface intersected by an associated measurement axis. The resulting distance measurements are either displayed to an operator or communicated to a processing system, together with at least one image of the optical target captured by the camera. The processing system is configured with software instructions to evaluate an image of the optical target acquired by the camera system, together with the measured distances received from the distance sensors or input by the operator, and the relationships between the measurement axes and the optical target to determine spatial locations of the intersection points within a reference frame.40812179.V1 6

[0018] A system is disclosed which includes a machine-vision vehicle measurement and / or inspection system having at least one camera system operatively coupled to a processing system, and a SCM tool comprising a non-contact distance sensor secured to a set of optical targets such that a measurement axis of the non-contact distance sensor is in a known or determinable relationship to the set of optical targets.

[0019] A further system is disclosed which includes a machine-vision vehicle measurement and / or inspection system having at least one optical target in a known or determined position and orientation within a reference frame, a processing system, and a SCM tool comprising a non-contact distance sensor secured to a camera such that a measurement axis of the non-contact distance sensor is in a known or determinable relationship to an optical axis of the camera’s field of view.

[0020] A method of the present disclosure utilizes an SCM tool to identify a three- dimensional spatial position of a measurement point during measurement and / or inspection of a vehicle disposed within a vehicle service area. A measurement axis of a non-contact distance sensor on the SCM tool is positioned and oriented to project an illuminating point of light onto the selected location on a vehicle or on a surface within a vehicle service area, and a measurement of the distance from the sensor to the selected location is captured. Concurrently, an image of at least one optical target on the SCM tool secured in a known or determinable relationship to the measurement axis of the non-contact distance sensor is acquired by an observing camera. Processing the acquired image identifies a relative spatial position and orientation of the optical target within a reference frame. The relative spatial position and orientation of the optical target, the known or determined relationship between the optical target and the measurement axis of the non-contact distance sensor, and the distance along40812179.V1 7the measurement axis to the selected location are utilized to establish a spatial position of the selected location within a reference frame.

[0021] In a variation of the method, a camera carried on the SOM tool acquires an image of the illuminated point of light to establish a record of the selected location for which the spatial position is established.

[0022] In a further variation of the method, the non-contact distance sensor is incorporated into a handheld SCM tool to enable an operator to determine a set of spatial coordinates for the selected location within a common frame of reference. Upon activation a plurality of distance measurements to the selected location are acquired during an observation period, and the resulting measurements are averaged to establish a representative distance to the selected spatial location from the noncontact distance sensor during an observation period, accounting for variance introduced by the operator holding the SCM tool. Concurrently, two or more images of an optical target secured in a known or determinable relationship to the measurement axis of the non-contact distance sensor are acquired by an observing camera. The resulting images are processed to determine a relative spatial position and orientation of the optical target within a reference frame. The relative spatial position and orientation of the optical target, the known or determined relationship between the optical target and the measurement axis of the non-contact distance sensor, and the representative distance along the measurement axis to the measurement point are utilized to establish a representative spatial position of the measurement point within the reference frame.

[0023] In yet another embodiment, the present disclosure sets forth a method for performing a vehicle measurement, inspection, and / or ADAS sensor calibration procedure on a vehicle parked within a vehicle service area. A set of wheel alignment40812179.V1 8optical targets are secured to the vehicle’s wheels, and are imaged by a set of cameras. The resulting images are evaluated by a processing system to identify relative spatial positions and orientations of each wheel alignment optical target, from which vehicle parameters as wheel alignment angles, relative positions, and relative orientations within the vehicle service area are determined. To determine a relative position of an ADAS sensor or reference point on the vehicle, a measurement tool comprised of a non-contact range finder and at least two optical targets is positioned and oriented to align a measurement axis of the range finder with the ADAS sensor or reference point while simultaneously maintaining at least one optical target within a field of view of at least one of the cameras. A distance measurement from the noncontact range finder to the ADAS sensor or reference point is acquired and communicated to the processing system, together with an image capturing at least one of the optical targets. The captured image, distance measurement, and a known or determined relationship between the optical targets and the measurement axis of the non-contact range finder are evaluated to determine a relative spatial position of the ADAS sensor or reference point. The relative spatial position of the ADAS sensor or reference point is utilized by the processing system to complete a vehicle measurement, inspection and / or ADAS sensor calibration procedure, such as by establishing a reference point for the placement of a calibration target or fixture, or by enabling comparison of an actual location against an expected location.

[0024] The foregoing features, and advantages set forth in the present disclosure as well as presently preferred embodiments will become more apparent from the reading of the following description in connection with the accompanying drawings.BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

[0025] In the accompanying drawings which form part of the specification:40812179.V1 9

[0026] Figure 1 is a perspective illustration of a prior art vehicle measurement and / or inspection system;

[0027] Figure 2 is a top plan view of the vehicle measurement and / or inspection system positioned in a vehicle service area together with a vehicle undergoing inspection;

[0028] Figure 3 is a perspective view of a spatial coordinate measurement tool of the present disclosure;

[0029] Figure 4 is a second perspective view of the spatial coordinate measurement tool of Fig. 3;

[0030] Figure 5 is a perspective view of the spatial coordinate measurement tool of Fig. 3 mounted to a support stand;

[0031] Figure 6 is a perspective view similar to Fig. 5;

[0032] Figure 7 is a view similar to Fig. 2, with a spatial coordinate measurement tool positioned within a camera field of view and oriented to identify a location on a rear quarter panel of the vehicle;

[0033] Figure 8 is a view similar to Fig. 7, with the spatial coordinate measurement tool oriented to identify a location on a floor surface at a spaced distance rearward of the vehicle and on the vehicle centerline;

[0034] Figure 9 is a front left perspective view of a second embodiment of the spatial coordinate measurement tool of he present disclosure, having optical targets visible from opposite lateral side;

[0035] Figure 10 is a rear right perspective view of the spatial coordinate measurement tool of Fig. 9;

[0036] Figure 11 is a bottom perspective view of the spatial coordinate measurement tool of Fig. 9;40812179.V1 10

[0037] Figure 12 illustrates the spatial coordinate measurement tool of Fig. 9 temporarily secured to a support stand;

[0038] Figure 13 is a top perspective view of an exemplary handheld non-contact distance measurement sensor;

[0039] Figure 14 is a bottom perspective view of the distance measurement sensor of Fig. 13;

[0040] Figure 15 is a perspective illustration of a spatial coordinate measurement tool body of the present disclosure configured to receive the non-contact distance measurement sensor of Fig. 13;

[0041] Figure 16 illustrates the spatial coordinate measurement tool body of Fig. 15 with the non-contact distance measurement sensor of Fig. 13 secured therein; and

[0042] Figure 17 is a perspective view of an embodiment of the spatial coordinate measurement tool of Fig. 15 coupled to a multi-axis gimbal-mounted optical projection system.

[0043] Corresponding reference numerals indicate corresponding parts throughout the several figures of the drawings. It is to be understood that the drawings are for illustrating the concepts set forth in the present disclosure and are not to scale.

[0044] Before any embodiments of the claimed invention are explained in detail, it is to be understood that the claimed invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the drawings.DETAILED DESCRIPTION

[0045] The following detailed description illustrates the claimed invention by way of example and not by way of limitation. The description enables one skilled in the art to make and use the present disclosure, and describes several embodiments,40812179.V1 11adaptations, variations, alternatives, and uses of the present disclosure, including what is presently believed to be the best mode of carrying out the present disclosure.

[0046] Machine vision vehicle measurement systems utilized to measure vehicle wheel alignment and / or calibrate the position and orientation of vehicle onboard ADAS sensors typically utilize one or more cameras to acquire images of optical targets located within a field of view. These optical targets may be temporarily secured to the vehicle, such as on the vehicle wheels, located on fixtures positioned in proximity to the vehicle, or placed on surfaces within the vehicle surface area. Acquired images of the optical targets are conveyed from the cameras to an associated processing system, wherein relative spatial position and orientation data associated with each observed optical target is determined and utilized to either establish a vehicle measurement, such as a wheel alignment angle, a vehicle position or orientation, or a fixture position and / or orientation.

[0047] An exemplary vehicle measurement and / or ADAS calibration system 100 is described in co-pending U.S. Patent Application Publication No. 2024-0272277 A1 which is herein incorporated by reference, and is shown in Figures 1 and 2. The system 100 includes a base 102 supporting an upright structure 104. As illustrated in Fig. 1 , the upright structure 104 comprises front and rear columns 104a, 104b located on the lateral midline X of the base 102 but those of ordinary skill will recognize that a variety of column configurations may be utilized as needed. A cabinet 108 is located on the base 102 to hold electronic components such as a processing system and provides various storage compartments. A vertically movable mounting structure 1 10 carried on the forward-facing side of the upright structure 104 supports an instrumentation crossbeam 112 and a target rail member 114. Vertical movement of the mounting structure 110 ranges between upper and lower limits along the upright40812179.V1 12structure 104. Additional multi-axis movement of the instrumentation crossbeam 1 12 and target rail member 114 is enabled by adjustment mechanisms within the mounting structure 110.

[0048] Those of ordinary skill in the art of vehicle measurement and ADAS calibration will recognize that a variety of components may be carried on the mounting structure 110 for positioning relative to a vehicle undergoing service. The instrumentation crossbeam 112 supports at least one optical camera system 113 at each outboard end, and may optionally include a pair of laterally spaced optical projectors 1 15 mounted on multi-axis gimbals 1 17, such as shown in U.S. Patent No. 10,634,488 B2 to Stieff et al. The processing system (not shown) is operatively coupled to receive image data from each optical camera system 113 and is configured with software instructions to process the received data, as well as to provide control signals to any optional optical projectors 115 and associated multi-axis gimbals 117. The target rail member 114 provides one or more mounts 122 for receiving interchangeable ADAS calibration target panels such as radar-reflective targets or optical targets (not shown). The mounts 122 are fixed in place on the target rail member 114 or are alternatively configured for movement along a horizonal axis of the rail, such as by engagement of rollers and tracks or any other suitable coupling permitting linear movement. Alternatively, one or more electronic display panels, such as an LED display, capable of presenting images of ADAS calibration targets associated with a vehicle undergoing service recalled from a database by the connected processing system may be provided on the target rail member 114, coupled to the mounts 122, or otherwise affixed to the mounting structure 110. For some vehicle ADAS calibration procedures, a radar-reflective target panel (not shown) is positioned in front or the vehicle and inline with the radar emitting ADAS sensor onboard the vehicle.40812179.V1 13

[0049] To facilitate positioning the ADAS calibration support structure within a vehicle service area, the base 102 includes a set of rolling elements, such as casters, or wheels, or a combination thereof to enable the support structure 100 to be moved over a supporting floor surface to a desired location relative to the vehicle undergoing measurement or inspection within the vehicle inspection area. Typically, during an ADAS inspection or calibration procedure, the base 102 is positioned at a selected distance from the front of the vehicle, aligned with the vehicle centerline.

[0050] Turning to Figures 3 and 4, a first embodiment of the spatial coordinate measurement tool 200 (hereinafter SCM tool 200) is shown. The SCM tool 200 is configured for use by a vehicle measurement and / or ADAS calibration system 100 to facilitate identification of a three-dimensional spatial position such as on a vehicle body, calibration fixture, or floor surface which is not directly visible to the associated optical camera systems 1 13. The SCM tool 200 includes a body 202 sized to be carried and held by an operator. The body 202 provides at least one surface 204 supporting at least one optical target 206, with each optical target 206 comprising at least one target element 208 observable by the optical camera systems 113. Target elements may be defined by LEDs or other light sources, contrasting markings on the surface 204, or the presence I absence of retro reflective materials on the surface 204. In one embodiment, the target body 202 and optical target 206 on the surface 204 has substantially the same configuration as a wheel-mounted optical target utilized to acquire vehicle wheel alignment measurements.

[0051] A non-contact distance sensor 210 is secured to the body 202 in a fixed relationship such that a measurement axis 210a of the non-contact distance sensor210 is in a determinable relationship to the optical target(s) 206. The sensor 210 may be removably secured to the body by a fixed mounting bracket 21 1 , such as shown in40812179.V1 14Figs. 3 and 4, by an adjustable mounting bracket having two or more predetermined or known positions, or by a controlled-movement gimbal having one or more axis of rotation (as shown in Fig. 17) having one or more axes of rotation. The non-contact distance sensor 210 may be an optical time-of-flight sensor, a laser range finder, or any other suitable sensor configured to acquire a measure of distance to a point on a surface intersected by the measurement axis 210a. Preferably, when the sensor 210 is activated, a beam of light is projected along the measurement axis 210a, illuminating the point to which the distance will be measured. Activation may be by a trigger button located on the sensor 210, a remote trigger button located on the sensor body 202, or by a signal communicated from the processing system via either a wired or wireless communications link. Distance measurements acquired by the sensor 210 are displayed to an operator on a display 212 as shown in Fig. 3, and / or are communicated to the processing system, either manually by an operator, or automatically via suitable communications link. Communicated or displayed measurements may be either instantaneous measurements representative of the distance measured when the sensor is triggered, or may represent an average of two or more sequential measurements acquired over a period of time. The sensor 210 may be configured to continuously acquire measurement data once activated, or may be configured to do so only in response to the trigger or activation signal. Preferably the sensor 210 is provided with a suitably sized rechargeable or replaceable battery power source to enable an operator to perform vehicle service procedures and acquire measurements for at least a full workday without the need to stop and recharge the battery.

[0052] In an alternative, the distance sensor is an extendable I retractable measurement tool, such as a tape measure or pull-out string, wherein distance is measured by an amount of extension from a home or rest position to the selected point40812179.V1 15of interest along a measurement axis. The distance may be measured electronically such as by a potentiometer monitoring rotational movement of a reel, or manually identified by an operator (such as in the case of reading a tape measure). The axis along which the measurement tool extends and retracts from the base 202 is in a known or determinable relationship to the optical target 206.

[0053] While not shown, those of ordinary skill in the art will understand that additional distance sensors 210 may be mounted to the sensor body 202 with associated measurement axes in known or determinable relationships to the optical target(s) 206, enabling the capture of distance measurements to multiple points simultaneously. For example, by acquiring measurements to two separate measurement points, the SCM tool 200 may be utilized to determine a spatial separation between two points on a vehicle body or frame, or between the vehicle body and a floor surface (ride height).

[0054] In a further variation, the non-contact distance sensor 210 includes additional sensor components, such as MEMS accelerometers and / or gyroscopes capable of measuring properties such as, but not limited to, the pitch, the yaw, or the roll of the sensor 210 relative to gravity. Any acquired measurements of such properties may be communicated and / or displayed in the same manner as an acquired distance measurement. An exemplary uses of such acquired measurements enable a processing system associated with the vehicle measurement and / or ADAS calibration system 100 to determine an orientation of the SCM tool 200 relative to either an observing camera’s frame of reference, or to a gravity reference. Similarly, a comparison of acquired measurements of a pitch and roll of the sensor 210 with an observed spatial orientation of the SCM tool 200 can be used to determine the relationship between the sensor 210 and the optical target(s) 206 of the SCM tool 200.40812179.V1 16

[0055] As shown in Figures 3-6, the body 202 of the SOM tool 200 may be configured for removable attachment to a support stand 300, allowing the SCM tool 200 to be readily located at various positions about a vehicle service area without requiring an operator to continuously hold the tool in a steady state during use. An exemplary stand suitable for supporting the SCM tool 200 is shown in co-pending US Patent Application Publication No. 2023 / 0386080 A1 to Cejka et al., which is herein incorporated by reference. Temporary attachment of the SCM tool 200 to the stand 300 may be facilitated by a mounting bracket 214 secured to the body 202. The mounting bracket 214 is configured with a plurality of protrusions 216 which are configured to engage with matching notches 302 in a receiver 304 carried on the stand 300. The protrusions 216 may be configured to additionally serve as feet for placement of the SCM tool 200 in a horizontal orientation on a floor surface. Those of ordinary skill in the art will recognize that the configuration of the mounting bracket 214 and receiver 304 may be varied from that which is described herein without departing from the scope of the invention so long as the SCM tool 200 may be temporarily secured to a suitable support stand in a stable position. For example, a threaded receiver in the body of the SCM tool 200 would allow the tool to be secured to a matching connector on a conventional camera support tripod.

[0056] As shown in Figures 7 and 8, the SCM tool 200 may be utilized with a vehicle measurement and / or ADAS calibration system 100 to identify a three-dimensional spatial position of a measurement point MP located on a vehicle (such as, but not limited to, a vehicle body part, frame, attachment point, emblem, etc.) or on a surface within a vehicle service area (such as, but not limited to, a floor or vehicle lift) during measurement and / or inspection of a vehicle disposed within a vehicle service area.To obtain a spatial position measurement, the SCM tool 200 is positioned such that40812179.V1 17the optical target(s) 206 are visible within the field of view (FOV) of at least one camera system 1 13, and with the measurement axis 210a oriented to project an illuminating point of light onto the selected measurement point MP. A measure of the distance from the sensor to the illuminated point of light along the measurement axis 210a is acquired by the non-contact distance sensor 210. Concurrently, an image of the optical target(s) 206 secured in a known or determinable relationship to the measurement axis 210a is acquired by an observing camera system 1 13. The resulting image is communicated to a processing system configured with software instructions to determine a relative spatial position and orientation of the optical target 206 within the reference frame of the observing camera system 1 13. The relative spatial position and orientation of the optical target 206, the known or determined relationship between the optical target 206 and the measurement axis 210a of the non-contact distance sensor 210, and the distance along the measurement axis 210a to the measurement point MP, are utilized by the processing system to calculate a three-dimensional spatial position of the measurement point MP within a reference frame of the observing camera system 113. The processing system is configured to use the spatial position and orientation of the optical target(s) 206 as a starting point for a vector defined by the measured distance along the measurement axis 210a, and calculates the spatial position of the end-point of the vector, which correspond to the spatial position of the measurement point MP illuminated by the distance sensor 210. It should be noted that the measurement point MP itself may not be visible to the camera system 113.

[0057] Exemplary uses for the calculated spatial position include, but are not limited to, confirming a location and / or an orientation of a component on the vehicle, measuring position and orientation of a drive wheel on a 3-wheel vehicle, measuring an ADAS inspection reference point for placement of either an ADAS fixture and / or40812179.V1 18target, measuring a vehicle body parameter such as ride height or body orientation, confirmation of correct operator placement of ADAS fixtures and / or targets, and measuring vehicle surroundings or floor surfaces to aid or guide placement of ADAS systems, fixtures, and targets. Additional exemplary uses include evaluating vehicle body or frame damage, and / or confirming proper installation and repair of vehicle body or frame components.

[0058] Utilization of the SCM tool 200 as a handheld device by an operator is affected by the operator’s ability to hold to SCM tool 200 stationary during image acquisition and to maintain the measurement axis 210a in alignment with the intended measurement point MP. Movement of the SCM tool 200 during image acquisition may reduce the accuracy of the spatial position and orientation determination of the optical target(s) 206, while failure to maintain the measurement axis 210a in alignment with the intended measurement point MP may result in calculated spatial coordinates which are offset from the intended measurement point MP. Accordingly, when utilized as a handheld device, or in any other situation wherein a high degree of accuracy is required, a plurality of distance measurements to the intended measurement point MP are acquired during an observation period, and the resulting measurements averaged by the processing system to reduce the impact of operator movement. Additionally, multiple images of the optical target(s) 206 on the tool body 202 are acquired and processed to identify an averaged representative the spatial position and orientation for the optical target during the same observation period. Those of ordinary skill in the art will recognize that averaging multiple measurements of distance and / or determined spatial positions and orientations may be utilized even when the SCM tool 200 is affixed to a supporting stand 300 or placed on a stable surface during use.40812179.V1 19

[0059] In another configuration, a supplemental camera (not shown) is carried on the tool body 202 with a field of view oriented to capture the measurement point MP to which the distance sensor210 is acquiring a distance measurement. Images captured by the supplemental camera can be conveyed to the processing system together with the captured distance measurements, and may be stored as a record of the measurement point or other visible features in the environment of the measurement point.

[0060] In yet another configuration, an inertial measurement unit (IMU), inclinometer, or other gravity-reference means is carried on the tool body 202 or is a component of the distance sensor 210. By calibrating the IMU to a reference, such as a second IMU associated with the processing system, the SCM tool 200 provides an indication of gravity direction, enabling the SCM tool 200 and / or a stand or fixture onto which it is secured, to be leveled or aligned relative to gravity.

[0061] In a further embodiment, the optical target(s) 206 on the tool body 202 are replaced by a camera (not shown) having a field of view with an optical axis in a known or determinable relationship to the measurement axis 210a of the distance sensor 210. During operation, the camera on the tool body 202 captures an image of an optical target located at a known position and orientation within a spatial frame of reference. The resulting image, together with a captured distance measurement to the measurement point MP are communicated to the processing system, wherein the observed target image, the distance measurement, and the relationship between the camera optical axis and the measurement axis 210a are utilized to determine the spatial position of the measurement point MP within the spatial frame of reference using conventional vector relationships.40812179.V1 20

[0062] A method of the present disclosure enables a vehicle measurement, inspection, and / or ADAS sensor calibration procedure using a machine-vision measurement system 100. Initially, a vehicle 10 undergoing service is parked within a service area. A set of alignment measurement optical targets are secured to the vehicle wheels, and are imaged by a set of cameras 113. The resulting images are evaluated by a processing system to identify the relative spatial positions and orientations of each observed optical target, from which vehicle parameters as wheel alignment parameters, relative position, and relative orientation within the vehicle service area are determined. To determine a relative position of an ADAS sensor or reference point on the vehicle, an SCM tool 200 comprising at least one non-contact range finder 210 and at least one associated optical target 206 is positioned and oriented to align a measurement axis 210a of the range finder 210 with the ADAS sensor or reference point on the vehicle, while simultaneously maintaining the associated optical target 206 within a field of view of at least one of the cameras 113. A distance measurement from the non-contact range finder 210 to the ADAS sensor or reference point is acquired and communicated to the processing system, together with an image of the associated optical target 206. The image, distance measurement, and a known or determined relationship between the associated optical target 206 and the measurement axis 210a of the non-contact range finder 210 are evaluated to determine a relative spatial position MP of the ADAS sensor or reference point within a coordinate system of the observing camera 113. Spatial locations within the coordinate system of the observing camera 113 may be converted to any reference frame for which a relationship to the camera coordinate system is known, such as, but not limited to, a vehicle coordinate reference system, or a floor-plane coordinate reference system.40812179.V1 21

[0063] Once determined, the relative spatial position of the ADAS sensor or reference point is utilized by the processing system to complete a vehicle measurement, inspection, and / or ADAS sensor calibration procedure, such as by establishing a reference point for the placement of a calibration target or fixture, or by enabling comparison of a measured location against an expected location.

[0064] Turning to Figures 10-12, an alternate embodiment spatial coordinate measurement tool 1200 (hereinafter SCM tool 1200) is shown for use with a vehicle measurement and / or ADAS calibration system 100 to facilitate identification of a three- dimensional spatial position such as on a vehicle body, calibration fixture, or floor surface. The SCM tool 1200 includes a body 1202 which is laterally symmetric about a longitudinal axis, sized to be easily carried and held by an operator. The body 1202 provides a set of laterally spaced, symmetrically aligned, elongated planar surfaces 1204A-1204D each of which supports an associated optical target 1206. As best seen in Figures 9 and 10, a first pair of surfaces 1204A and 1204B are oriented towards a first lateral side of the body 1202, and are preferably aligned in parallel. A second pair of surfaces 1204C and 1204D are oriented towards an opposite lateral side of the body 1202 and are preferably aligned in parallel. The opposing orientation of each pair of surfaces 1204 enables at least one associated optical target 1206 to be visible when the SCM tool 1200 is viewed from opposite directions. Surfaces 1204A and 1204D are symmetric with each other about the longitudinal axis, and surfaces 1204B and 1204C are symmetric with each other about the longitudinal axis. However, it will be understood that the surfaces on opposite lateral sides of the body 1202 do not need to be symmetric, provided that they are capable of supporting associated optical targets 1206. The individual optical targets 1206 on each surface 1204A-1204D incorporate target elements 1208 observable by a camera system 113 such as on the40812179.V1 22ADAS calibration system 100. Target elements may be defined by LEDs or other light sources, contrasting markings on the surface 1204, or the presence I absence of retroreflective materials on the surface 1204. In one embodiment the optical targets 1206 on each surface 1204 are substantially the same as a optical targets utilized to acquire vehicle wheel alignment measurements. Additional visible markings 1220 located along a lateral edge of the body 1202 encode tool identification data. The tool identification data enables a processing system to distinguish between multiple SCM tools 1200 visible within a captured image, as well as to identify which lateral side of the body 1202 is visible. A non-contact distance sensor 1210 is secured within the body 1202 such that a measurement axis 1210a of the non-contact distance sensor 1210 is held in a fixed and determinable relationship to the optical target(s) 1206.

[0065] Preferably, the non-contact distance sensor 1210 is an optical time-of-f light sensor or laser range finder configured to acquire a measure of distance to a point on a surface intersected by the measurement axis 1210a. When the distance sensor 1210 is activated, a beam of light is projected along the measurement axis 1210a, illuminated the point to which the distance will be measured. In further variations the non-contact distance sensor 1210 may include, as noted previously, additional capability to function as an inclinometer and / or gyroscope capable of measuring rotational orientation about one or more axes (pitch, yaw, roll and / or an orientation relative to gravity). Multiple sensors having different functionality may be contained with the body 1202, or temporarily secured in a known position and orientation to a recess 1400 of the body 1203 by engagement between reference features 1302 and one or more registration points 1402.

[0066] Activation of the distance sensor 1210 is preferably by a signal communicated from the processing system via either a wired or wireless communications link.40812179.V1 23Optionally, an operator may manually initiate activation of the distance sensor 1210 via a suitable control interface associated with the distance sensor 1210. Distance measurements acquired by the distance sensor 1210 are either presented to an operator on a display 1304 or communicated to the processing system automatically via the communications link. Communicated measurements may be either instantaneous measurements representative of the distance measured when the sensor is triggered, or may represent an average of two or more sequential measurements acquired over a period of time. The distance sensor 1210 may be configured to continuously acquire measurement data once activated, or may be configured to do so only in response to the trigger or activation signal. Preferably the distance sensor 1210 is provided with a suitably sized rechargeable or replaceable battery power source to enable an operator to perform vehicle service procedures and acquire measurements for at least a full workday without the need to stop and recharge the battery.

[0067] As shown in Figures 11-12, the body 1202 of the SCM tool 200 is configured for removable attachment to a support stand 300, allowing the SCM tool 1200 to be located at various positions about a vehicle service area without requiring an operator to continuously support the tool in a steady state during use. An exemplary stand suitable for supporting the SCM tool 1200 is shown in the co-pending US Patent Application Publication No. 2023 / 0386080 A1 to Cejka et al. Temporary attachment of the SCM tool 1200 to the stand 300 is facilitated by a magnetic mounting foot 1214 secured to the underside of body 1202 by a suitable coupling, such as a ball joint 1215.The mounting foot 1214 magnetically engages a metallic surface 1314 carried on the stand 300 and allows the SCM tool 1200 to be oriented about the ball joint 1215 to align the measurement axis 1210a with selected measurement point. An orientation40812179.V1 24of the SCM tool 1200 about the ball joint 1215 can be locked by pressing a clamp element 1216 against a surface of the ball joint 1215 via a spring-biased threaded knob 1218. Those of ordinary skill in the art will recognize that the configuration of the mounting foot 1214, ball joint 1215, clamp element 1216 and knob 1218 may be varied from that which is described herein without departing from the scope of the invention so long as the SCM tool 1200 may be temporarily held in a selected orientation on the stand 300.

[0068] In a further variation, the SCM tool 1200 is configured with a body 1203 adapted to receive a distance sensor 1210 contained with a hand-held enclosure 1300, such as shown in Figs. 13-14. As shown at Figure 15-16, the body 1203 includes a recess 1400 for removably receiving the enclosure 1300 and for unobstructed viewing by the distance sensor 1210 along the measurement axis 1210A. Within the recess 1400, a set of registration points 1402 positively engage with corresponding reference features 1302 on an underside of the enclosure 1300, such as by magnetic attachment. The engagement between the registration points 1402 and the reference features 1302 ensures that the measurement axis 1210a of the distance sensor 1210 is located in a fixed and determinable relationship to the optical target(s) 1206 when the enclosure 1300 is seated within the recess 1400 as shown in Fig. 16.

[0069] Similar to the SCM tool 200 shown in Figures 7 and 8, the SCM tool 1200 may be utilized with a vehicle measurement and / or ADAS calibration system 100 to identify a three-dimensional spatial position of a measurement point MP located on a vehicle (such as, but not limited to, a vehicle body part, frame, attachment point, emblem, etc.) or on a surface within a vehicle service area (such as, but not limited to, a floor or vehicle lift) during measurement and / or inspection of a vehicle disposed within a vehicle service area. To obtain a spatial position measurement, the SCM tool 1200 is40812179.V1 25positioned such that at least one optical target 1206 is visible within the field of view (FOV) of an observing camera 113, and with the measurement axis 1210a oriented to project an illuminating point of light onto the selected measurement point MP which may not be within the FOV of the observing camera 113. A measure of the distance to the illuminated point of light along the measurement axis 1210a is acquired by the non-contact distance sensor 1210. Concurrently, an image of the optical target(s) 1206 is acquired by the observing camera 113. The resulting image is communicated to the processing system configured with software instructions to determine a relative spatial position and orientation of the optical target 1206 within the reference frame of the observing camera 113.

[0070] The processing system calculates a three-dimensional spatial position of the measurement point MP within the observing camera’s reference frame utilizing the measured distance, the relative spatial position and orientation of the optical target(s) 1206, and the known or determined relationship between the optical target(s) 1206 and the measurement axis 1210a. The processing system is configured to use the spatial position and orientation of the optical target(s) 1206 as a starting point for a vector defined by the measured distance along the measurement axis 1210a, and calculates the spatial position of the end-point of the vector, which correspond to the three-dimensional location of the measurement point MP illuminated by the distance sensor 1210 within the given spatial frame of reference.

[0071] Exemplary uses for the calculated spatial position include, but are not limited to, confirming a location and / or an orientation of a component on the vehicle, measuring or locating an ADAS inspection reference point for placement of either an ADAS fixture and / or target, measuring or locating a vehicle body parameter such as ride height or body orientation, confirmation of correct operator placement of ADAS40812179.V1 26fixtures and / or targets, and measuring or locating vehicle surroundings or floor surfaces to aid or guide placement of ADAS systems, fixtures, and targets.

[0072] A method of the present disclosure facilitates a vehicle measurement, inspection, and / or ADAS sensor calibration procedure using a machine-vision measurement system 100. Initially, a vehicle 10 undergoing service is parked within a vehicle service area. A set of optical targets are secured to the vehicle wheels, and are imaged by a set of cameras 113. The resulting images are evaluated by a processing system to identify the relative spatial positions and orientations of each observed optical target, from which vehicle parameters as wheel alignment parameters, relative position, and relative orientation within the vehicle service area are determined. To determine a relative position of an ADAS sensor or reference point on the vehicle, the SCM tool 1200 is positioned and oriented to align a measurement axis 1210a of the distance sensor 1210 with the ADAS sensor or reference point on the vehicle, while simultaneously maintaining at least one associated optical target 1206 within a field of view of at least one of the cameras 113. A measurement from the distance sensor 1210 to the ADAS sensor or reference point is acquired and communicated to the processing system, together with an image of the associated optical target 1206. The image, distance measurement, and a known or determined relationship between the associated optical target 1206 and the measurement axis 1210a of the distance sensor 1210 are evaluated to determine a relative spatial position MP of the ADAS sensor or reference point within a coordinate system of the camera 113. Spatial locations within the coordinate system of the camera may be converted to any reference frame for which a relationship to the camera coordinate system is known, such as, but not limited to, a common vehicle coordinate reference system or a floor-plane coordinate reference system.40812179.V1 27

[0073] Once determined, the relative spatial position of the ADAS sensor or reference point may be utilized by the processing system to complete a vehicle measurement, inspection, and / or ADAS sensor calibration procedure, such as by establishing a reference point for the placement of a calibration target or fixture, or by enabling comparison of a measured location against an expected location.

[0074] In a further variation shown in Figure 17, an SCM tool 1200 is configured to carry a gimbal mount 1500 having one or more axis of rotation (X, Y, Z). The gimbal mount 1500 is secured to the SCM body 1202 such that an orientation of each gimbal axis of rotation (X, Y, Z) is known or determinable relative to the optical targets 1206. The gimbal mount 1500 supports one or more tools 1502, such as a camera, a distance measurement sensor, and / or an optical emitter (such as a laser). Controlled rotation of the gimbal mount 1500 about the axes of rotation in response to commands received from a processing system aligns the supported tool 1502 to a selected orientation relative to the optical targets 1206. The commands may be conveyed wireless using any suitable communications protocol, or may be communicated directly via a wired connection without departing from the scope of the disclosure. In a hand-held configuration, the gimbal mount 1500 may include sufficient sensors and feedback circuits to provide stabilization for the supported tool 1502 against shake or vibration.

[0075] During use, the optical targets 1206 are observed by the camera system 113, enabling the processor to determine the spatial position and orientation of the optical target within a selected frame of reference. If the supported tool 1502 is a non-contact distance sensor configured to measure a distance along a measurement axis, the gimbal mount 1500 is directed by signals from the processing system to steer the measurement axis of the supported tool 1502 to intersect a set of coordinates within40812179.V1 28the spatial reference frame based on the determined spatial position and orientation of the optical targets 1206. Similarly, if the supported tool 1502 is a camera module, the gimbal mount 1500 can be directed by signals from the processing system to orient an axis of the camera module’s field of view as needed to enable acquisition of an image of a particular region, surface, or object located within the spatial reference frame. The resulting image can then be communicated wirelessly back to the processing system for evaluation. If the supported tool 1502 is an optical projector configured to project a beam of light along an axis, the gimbal mount 1500 is directed by signals from the processing system to steer the projection axis of the supported tool 1502 to intersect a set of coordinates within the spatial reference frame based on the determined spatial position and orientation of the optical targets 1206.

[0076] The present disclosure can be embodied in-part in the form of computer- implemented processes and apparatuses for practicing those processes. The present disclosure can also be embodied in-part in the form of computer program code containing instructions embodied in tangible media, or another computer readable non-transitory storage medium, wherein, when the computer program code is loaded into, and executed by, an electronic device such as a computer, micro-processor or logic circuit, the device becomes an apparatus for practicing the present disclosure.

[0077] The present disclosure can also be embodied in-part in the form of computer program code, for example, whether stored in a non-transitory storage medium, loaded into and / or executed by a computer, or transmitted over some transmission medium, wherein, when the computer program code is loaded into and executed by a computer, the computer becomes an apparatus for practicing the present disclosure.When implemented in a general-purpose microprocessor, the computer program code segments configure the microprocessor to create specific logic circuits.40812179.V1 29

[0078] As various changes could be made in the above constructions without departing from the scope of the disclosure, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.40812179.V1 30

Claims

CLAIMS:

1. A spatial coordinate measurement tool, comprising: a body having lateral symmetry about a longitudinal axis; a first target surface on a first lateral side of said body, said first target surface aligned parallel to a longitudinal axis of said body; a second target surface on a second lateral side of said body, said second target surface symmetric with said first target surface; wherein each target surface supports an associated optical target; and a distance measurement sensor caried by said body, said distance measurement sensor configured to measure a distance to a measurement point along a measurement axis aligned in a known or determinable relationship to each target surface.

2. The spatial coordinate measurement tool of claim 1 wherein said distance measurement sensor is one of a laser range finder or a time-of-flight range finder.

3. The spatial coordinate measurement tool of either claim 1 or 2 further including a wireless transceiver operatively coupled to said distance measurement sensor, said wireless transceiver configured to establish a communications link to a processing system for conveying commands to said distance measurement sensor and / or conveying measurement data from said distance measurement sensor.

4. The spatial coordinate measurement tool of claim 3 wherein said processing system is associated with a vehicle wheel alignment measurement system, a vehicle inspection system, or a vehicle ADAS calibration system.40812179.V1 315. The spatial coordinate measurement tool of any of claims 1-4 wherein said body further includes a mounting for temporary attachment of said body to a support stand.

6. The spatial coordinate measurement tool of any of claims 1 -5 further including at least one tool identifier on each lateral side of said body.

7. The spatial coordinate measurement tool of any of claims 1-6 wherein said first target surface is visible within a field of view aligned perpendicular to said first lateral side of said body; and wherein said second target surface is visible within a field of view aligned perpendicular to said second lateral side of said body.

8. The spatial coordinate measurement tool of claim 1 further including a third target surface, said third target surface located on said first lateral side of said body and aligned parallel to said second target surface; and a fourth target surface, said fourth target surface located on said second lateral side of said body and aligned parallel to said first target surface.

9. The spatial coordinate measurement tool of claim 1 wherein said distance measurement sensor is temporarily secured to said body magnetically or by engagement with a set of registration points.

10. A spatial coordinate measurement tool, comprising: a body; a first target surface on a first lateral side of said body, said first target surface having a first orientation relative to said body; a second target surface on a second lateral side of said body, said second target surface having a second orientation relative to said body, said second orientation different from said first orientation;40812179.V1 32wherein each target surface supports an associated optical target; and a distance measurement sensor caried by said body, said distance measurement sensor configured to determine a measure of distance to a point along a measurement axis aligned in a known or determinable relationship to each target surface.

11. The spatial coordinate measurement tool of claim 10 wherein said first and second target surfaces are symmetric about a lateral axis of said body.

12. The spatial coordinate measurement tool of either claim 10 or 11 further including at least one identification marking associated with a first lateral side of said body; and a second identification marking associated with a second lateral side of said body.

13. The spatial coordinate measurement tool of any of claims 10-12 further including a third target surface on a first lateral side of said body, said third target surface having a third orientation relative to said body; a fourth target surface on a second lateral side of said body, said fourth target surface having a fourth orientation relative to said body, said fourth orientation different from said third orientation; and wherein each of said third and fourth target surfaces supports an associated optical target.

14. The spatial coordinate measurement tool of claim 13 wherein said first and third orientations are identical, and wherein said second and fourth orientations are identical.40812179.V1 3315. The spatial coordinate measurement tool of claim 10 wherein said distance measurement sensor is temporarily secured to said body magnetically or by engagement with a set of registration points.

16. The spatial coordinate measurement tool of claim 10 further including a multi-axis inclinometer caried by said body in a known or determinable relationship to each target surface.

17. The spatial coordinate measurement tool of claim 16 wherein said multiaxis inclinometer is temporarily secured to said body magnetically or by engagement with a set of registration points.

18. The spatial coordinate measurement tool of any of claims 10-17 further including a wireless transceiver configured to establish a communications link to a processing system for conveying commands and / or measurement data.

19. The spatial coordinate measurement tool of claim 18 wherein said processing system is associated with a vehicle wheel alignment measurement system, a vehicle inspection system, or a vehicle ADAS calibration system.

20. The spatial coordinate measurement tool of any of claims 10-19 wherein said body further includes a mounting for temporary attachment of said body to a support stand.

21. A method for operating a vehicle measurement or inspection system having at least one camera, a processing system operatively coupled to receive images from the camera, and a spatial coordinate measurement tool having a body supporting a distance measurement sensor having a measurement axis in a known or determinable relationship to an optical target, comprising: positioning said spatial coordinate measurement tool with said optical target within a field of view of said at least one camera;40812179.V1 34aligning a measurement axis of said distance measurement sensor with a selected measurement point; acquiring an image of said optical target with said at least one camera; conveying said acquired image to said processing system; determining at said processing system, a spatial position and orientation of said optical target within a frame of reference from said acquired image; acquiring a measure of distance from said distance measurement sensor to said selected measurement point; conveying said acquired measure of distance to said processing system; and determining at said processing system a spatial position of said selected measurement point within said frame of reference utilizing said determined spatial position and orientation of said optical target, together with said acquired measure of distance.

22. The method of claim 21 further including validating said selected measurement point by comparing said determined spatial position with an expected spatial position.

23. The method of claim 22 further including the step of establishing a record of said determined spatial position and / or an outcome of said validation.

24. The method of claim 22 further including providing an operator with a visual representation of an outcome of said validation via a graphical user interface.

25. The method of claim 21 wherein said selected measurement point is an ADAS measurement reference point associated with a vehicle undergoing an ADAS component inspection or calibration.40812179.V1 3526. The method of claim 21 wherein said selected measurement point is a reference point associated with placement of an ADAS fixture relative to a vehicle undergoing an ADAS component inspection or calibration.40812179.V1 36

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