Abstract: An apparatus and method are provided for aligning the steerable (front) wheels or hubs of a vehicle with the fixed (rear) wheels or hubs in substantially parallel longitudinal alignment. The steerable wheels are thus set in a straight ahead position for connection of a steering wheel to the steering linkage in the corresponding straight ahead position. Laser devices measure the relative angles of the front and rear wheel hubs as the vehicle or chassis is carried along an assembly line. A computer controlled power wrench then rotates the steering gear to longitudinally align the plane of the steerable hub on one side of the vehicle substantially parallel with the plane of the fixed hub in the same side. The steering wheel is then installed so that both the steering wheel and the steerable wheels are set in the straight ahead position. Additional features are also disclosed.

Abstract: A device for determining the wheel and/or axle geometry of motor vehicles in an inspection room using an optical measuring device having at least two image pick-up devices, which, from at least two different perspectives, record images from a marking device (or optical target), inclusive of at least one wheel feature arranged on each wheel, and including an evaluation device. The marking device further includes an automobile body feature and a reference feature arrangement, including at least three reference features for use in obtaining geometrical wheel and axle data. The inspection room is defined between the reference feature arrangement and the driving surface plane. The position of the reference features in the inspection room is known or stored in the evaluation device. The marking device is detected while the motor vehicle is being driven past.

Abstract: An apparatus and method for automatically identifying faults in the operation of a machine vision measuring systems provides an improved self-diagnostic capability for machine vision based metrology and tracking systems. The method and apparatus validate performance of tracking operations, and detect deterioration that may be caused by electronic noise, environmental contamination, etc. A mathematical model of the target visualized by the system is created and stored. A target is imaged in the field and fiducials of the target are identified. Centroid positions of detected fiducials of the imaged target are compared to the centroid positions of fiducials in the mathematical model. When a fiducial is obscured or dirty, its geometric characteristics (such as centroid, brightness, edge smoothness, area, or shape) differ from the true or idealized values of the characteristics.

Abstract: A four sensor wheel aligner has a single omnidirectional angle sensor mounted on each of four vehicle support wheels. Each sensor is in optical communication with the other sensors. Data is produced from which toe, camber, caster and steering axis inclination angles are computed. No reference is made to vertical. Redundant data sets are produced which provide system reliability and error tracking features and maximum accuracy from available data sets. Frame distortion measurements are made to facilitate collision repair in coordination with wheel alignment.

Abstract: An apparatus for determining the position and/or alignment of objects such as motor vehicle wheels, and including targets for attachment to the objects, a pair of optical sensing means such as television cameras for viewing the targets, an electronic processing means connected to the optical sensing means for processing data relating to images of the targets to determine position and/or alignment information, and a display means for displaying the position and/or alignment information. The optical sensing means view a target located on each object and form an image of each target. Electronic signals corresponding to each of the images are transferred to the electronic processing means which correlates the image signals of each of the targets with the true shape of each target.

Abstract: An apparatus and method for determining the orientation parameters of a wheel-alignment optical target 10 affixed to a vehicle wheel 20 by a no-compensation wheel clamp 16. The wheel-alignment optical target includes a stub shaft 24 adapted for insertion within an axial bore 18 of the no-compensation wheel clamp after the wheel clamp is secured to the vehicle wheel. An optical imaging system observes the optical target and measures the orientation of the target face in a first position. The optical target is rotated partially about the longitudinal axis of the stub shaft, and the optical target is again observed and the orientation of the target face is again measured by the optical imaging system. By comparing the measured orientations of the optical target at the two rotational positions, a compensation vector Vc describing the alignment of the target face relative to the stub shaft is be determined and stored for subsequent uses of the optical target.

Abstract: A voice control system for an automotive service system includes a microphone, through which a technician can communicate voice commands to an item of automotive service equipment within the automotive service system, a speech processor module for converting the voice commands into digital instructions which can be processed by a system controller and for converting data from the system controller into synthesized voice audio, and a speaker for communicating the synthesized voice audio to the technician. The system of the present invention may also include a pair of goggles incorporating a heads-up display which displays the data from the system controller by virtual image in the technician's forward field of vision without blocking his general forward field of view.

Abstract: Apparatus and method for determining the alignment of a wheel of a vehicle includes mounting a known optical target to a wheel on the vehicle, the known optical target having a plurality of optical elements, each optical element having at least one straight edge disposed on a background, obtaining at least one video image of the optical target, estimating from the video image of the optical target the characteristics in said video image of a plurality of lines corresponding to projections onto the video image of the straight edges of the optical elements, and determining from the estimates of the characteristics the alignment of the wheel. A similar target for determining the position of a runway on which the vehicle is positioned is also disclosed.

Abstract: Measuring system for the measuring of wheel angles comprising cameras (21) pivotable on rear wheel (22) fastenings and looking both on front wheel marker arrangements (24) and a marker device (25) arranged perpendicular relative the length direction of the vehicle. The camera registers the angles of the wheel it is mounted on by viewing the marker device and the angles of the front wheel by subtracting the angles of the wheel with the camera from those obtained for the marker arrangement on the front wheel. The marker arrangement is diametrically symmetric and allows together with pivotability of the camera a rotating of the wheels over a half revolution so that possible mounting errors can be detected and correlated for.

Abstract: An apparatus and method for determining axial stability compares measured wheel runout and axial instability parameters with prescribed tolerances to determine if the wheel suffers from excessive wheel play. Axial stability and runout is determined and displayed on a monitor screen such that an alignment technician can quickly assess both the degree of present wheel misalignment and the feasibility of attempting to perform a realignment operation without first repairing worn or damaged suspension parts. The attitude and location of a wheel are measured with the wheel set in a first position to determine a first vector having a predetermined relation to the wheel. The wheel is rolled back a number of degrees to a second position and the attitude and location thereof are measured to determine a second vector also having the predetermined relation to the wheel. Rearward axis parameters including a rearward rotational axis vector and a rearward runout vector are determined based on the first and second vectors.

Abstract: An apparatus and methodology for diagnosing an alignment condition of a vehicle. The methodology includes determining an alignment condition of the vehicle using an apparatus set forth herein, and calculating a result corresponding to a difference between the determined alignment condition of the vehicle and specifications for a plurality of alignment conditions stored in a memory. The methodology further includes selecting one of a plurality of graphics stored in the memory, each corresponding to a value defined by the stored specifications, by determining the value to which the result corresponds, and outputting the selected one of the plurality of graphics.

Abstract: An apparatus for determining the position and/or alignment of objects such as motor vehicle wheels, and including targets for attachment to the objects, a pair of optical sensing means such as television cameras for viewing the targets, an electronic processing means connected to the optical sensing means for processing data relating to images of the targets to determine position and/or alignment information, and a display means for displaying the position and/or alignment information. The optical sensing means view a target located on each object and form an image of each target. Electronic signals corresponding to each of the images are transferred to the electronic processing means which correlates the image signals of each of the targets with the true shape of each target.

Abstract: A device used to align the rear end of a vehicle that can be mounted on the axle of the vehicle and that generates a linear laser beam that is perpendicular to the axis of the axle so that measurements can be made between the beam and the frame of the vehicle to assist in properly aligning the rear end of the vehicle relative to the frame.

Abstract: The present invention relates to a measurement system for measuring wheel angles and determining the position of chassis units on a vehicle. The measurement system includes a measuring unit which can be mounted on a vehicle and arranged to measure angles and distances in the horizontal plane with reference to the longitudinal axis of the vehicle, and in the vertical plane with reference to the vertical direction. The results of measurement are fed to a control unit, connected to the measuring unit by a lead. A computer which compiles and computes the measurement results, and provides information on the vehicle wheel alignment angles and the positions of vehicle chassis units by means of a display monitor or a printer connected to the control unit.

Abstract: An optical wheel alignment apparatus intended for race cars and other high performance road vehicles which provides an extremely accurate, low-cost, light-weight, portable and non-electrical method for toe and camber alignments even in space limited and hostile environments such as race car pit areas. Further, the apparatus is simple to operate, requires less that five-minutes set-up time and provides repeatable accuracy up to two minutes of a degree toe and 1/8" camber without the aid of computer control.

Abstract: An apparatus for determining the position and/or alignment of objects such as motor vehicle wheels, and including targets for attachment to the objects, a pair of optical sensing means such as television cameras for viewing the targets, an electronic processing means connected to the optical sensing means for processing data relating to images of the targets to determine position and/or alignment information, and a display means for displaying the position and/or alignment information. The optical sensing means view a target located on each object and form an image of each target. Electronic signals corresponding to each of the images are transferred to the electronic processing means which correlates the image signals of each of the targets with the true shape of each target.

Abstract: A moving vision sensor scans the image of an object by moving the transducer to create a topographic image map of the object in three dimensions. In a preferred embodiment, the vision sensors are disposed in a preset camber, caster, toe wheel alignment station within a vehicle assembly line. A first moving vision sensor maps the plane of the wheel in space for toe and camber audit and adjustment. A second moving vision sensor maps the axis of the king pin ball joint in space for caster audit and adjustment.

Abstract: The geometric inspection of wheeled vehicles is carried out by at least two casings facing each other and each comprising at least one light source and at least one optical receiver located behind a device for defining an image. The image-defining device is sensitive to radiation from the light source of the other opposite casing. The light source (12) of a first casing defines with the optical receiver (13) of a second opposite casing a first active spatial zone (A). The light source (8) of that second casing defines with the optical receiver (14) of the first casing a second active spatial zone (B). The two active spatial zones (A, B) are separated by a space (C) of predetermined width (d) to permit simultaneous operation of the two casings without mutual interference.

Abstract: An apparatus for determining the position and/or alignment of objects such as motor vehicle wheels, and including targets for attachment to the objects, a pair of optical sensing means such as television cameras for viewing the targets, an electronic processing means connected to the optical sensing means for processing data relating to images of the targets to determine position and/or alignment information, and a display means for displaying the position and/or alignment information. The optical sensing means view a target located on each object and form an image of each target. Electronic signals corresponding to each of the images are transferred to the electronic processing means which correlates the image signals of each of the targets with the true shape of each target.

Abstract: Apparatus and method for determining the alignment positions and orientations of vehicle wheels includes optical targets mounted on the wheels and optical targets mounted in a fixed relationship with respect to the surface on which the wheels are disposed. Video cameras are used to obtain images of the various optical targets and a computer is responsive to the images of the targets to determine values of wheel alignment parameters of the vehicle relative to said surface on which the vehicle wheels roll. Methods of calibrating such an apparatus and methods using such apparatus to determine the flatness of the surface on which the wheels roll are also disclosed.

Abstract: A method and apparatus for measuring the alignment of vehicle wheels includes a light source having two beams projecting on opposite directions. The source is mounted on the wheel approximately perpendicular to the wheel axis. Measuring scales are mounted along the paths of the beams in front of and behind the wheels. When taking measurements, the wheel is rotated 180.degree. after a first measurement and a second reading of the scales is made. The difference between the two sets of readings is used to determine the deviation of the light beam from the perpendicular to the wheel axis and this deviation is compensated for in measuring the wheel alignment. Optical sighting means such as a camera can be used in place of the two beam light source.

Abstract: A method of aligning a suspension of an automotive vehicle, the vehicle having a chassis secured at a predetermined height above the ground, a steering shaft secured to prevent movement thereof, and a hub, the method comprising the steps of providing a suspension measurement system comprising a light source, a reflector and a target, adjusting the height of the suspension to a height above the ground that is substantially equal to a radius of a tire used with the suspension, removably attaching the reflector to the hub wherein the reflector is vertically oriented and substantially perpendicular to the hub central axis, positioning the target a predetermined distance from the reflector, directing a light beam to the center of the reflector for reflection onto the target, the light source being positioned such that the reflected beam of light is substantially coplanar with the directed light beam, incrementally adjusting the height of the suspension in relation to an initial height and applying indicia to locat

Abstract: An apparatus for determining the alignment of a motor vehicle's wheels and including targets (22L, 22R, 24L, 24R) which either form part of the wheels or are attached thereto, an optical sensing means such as a television camera (30) for viewing the targets, an electronic processing means (32) connected to the optical sensing means for processing the target images to determine wheel alignment, and a display means (34, 36) for displaying the alignment information. The optical sensing means (30) views a target located on each wheel and forms an image of each target. Electronic signals corresponding to each of the images are transferred to the electronic processing means (32) which correlates the perspective image of each of the targets with the true shape of each target. In so doing, the processor (32) relates the dimensions of certain known geometric elements (62, 63) of the target with the dimensions of corresponding elements in the perspective image and calculates the alignment of the wheels of the vehicle.

Abstract: A system for measuring angular relationships of wheels of a vehicle includes a radiation source mounted with respect to a first wheel for providing a radiation signal, an image detector having an active array of pixels mounted with respect to a second wheel for receiving an image from the radiation source and for producing an output in response to the radiation signal, and a radiation detector disposed in the path of the radiation from the radiation source for detecting the presence of the radiation signal. A controller is responsive to the presence of the radiation signal to activate the image detector to receive the image from the radiation source and determine an alignment angle of a wheel of the vehicle from the output of the image detector. A mask is mounted between the radiation source and the detector for defining an image of the radiation source upon the detector, the mask preferably having at least three slits therein.

Abstract: A diagnostic vehicle alignment system includes an electronic controller for guiding a user through a series of diagnostic steps to determine probable causes for particular vehicle symptoms. Vehicle wheel alignment measuring instruments determine the alignment of at least one wheel of the vehicle. An input device is manually operable by a user for providing symptom identification and answers to diagnostic questions. A digital memory stores a set of possible causes for each selectable symptom and also stores diagnostic questions and an identification of diagnostic procedures. The stored diagnostic questions and procedures are preselected to eliminate possible causes of the selected symptom from consideration. A display is provided for displaying diagnostic questions and procedures to the user.

Abstract: Apparatus for determining shim changes to adjust the camber and caster of a vehicle wheel includes a memory for storing preselected information relating to dimensions of a vehicle wheel control arm for at least two different vehicles, the information being different for the two vehicles. The memory also stores vehicle wheel alignment specifications for the vehicles. Vehicle wheel alignment instruments measure the camber and caster of vehicle wheels. A computer is operatively connected to the memory and is responsive to the measurements from the vehicle wheel alignment instruments for comparing the measured camber and caster to corresponding caster and camber specifications for the vehicle wheel to determine required changes in camber and caster. The computer uses the required changes and the preselected dimensional information to determine the changes required in shims to adjust the measured camber and caster to the specifications.

Abstract: An automatic wheel alignment system for aligning the wheels of an automotive vehicle includes head units adapted for coupling to the wheels of the automotive vehicle and a hand held module. The wheel units provide angle information related to the alignment of the wheels of the automotive vehicle. The hand held module is coupled to the wheel alignment units and provides information to an operator through a liquid crystal display. The hand held module includes a controller and memory means. A keypad input is provided for receiving an input from the operator. The liquid crystal display includes an liquid crystal display matrix for forming an image. A contrast control means is coupled to the liquid crystal display and provides a contrast signal to the liquid crystal display.

Abstract: An automatic wheel alignment system for aligning the wheels of an automotive vehicle includes head units adapted for coupling to the wheels of the automotive vehicle and a hand held module. The wheel units provide angle information related to the alignment of the wheels of the automotive vehicle. The hand held module is coupled to the wheel alignment units and provides information to an operator through a liquid crystal display. The hand held module includes a controller and memory means. A keypad input is provided for receiving an input from the operator. The liquid crystal display includes an liquid crystal display matrix for forming an image. A contrast control means is coupled to the liquid crystal display and provides a contrast signal to the liquid crystal display.

Abstract: A device and method to align the wheels of motor vehicles. A beam of collimated light from a low power visible laser is split into two generally parallel beams by a partially transmitting mirror and a series of plane front surface mirrors positioned in front and along side the vehicle being serviced. The two beams are reflected from a set of plane mirrors attached to the rims of the wheels to be aligned. The vertical and horizontal angles of each of the wheel-mounted mirrors are set by calibrated lead-screws to cancel the angular displacement of the wheels expected when the wheels are properly aligned. The reflected beams are imaged through a large aperture beam combiner on a common viewing screen. Correct toe-in and camber settings are indicated when the laser beams reflected from the wheel-mounted mirrors overlap at the center of the viewing screen.

Abstract: A vehicle wheel alignment measurement system includes four infra-red emitter-detector units fixed by clamps to the vehicle wheels. Each unit includes a beacon and a rotatable detector coaxial with the beacon and driven by a motor. Angular rotation of the detector is sensed and signals from the four units are analyzed by a signal processing computer to give absolute position and relative angular measurements of the four wheels.

Abstract: A wheel alignment system is disclosed which measures the angles between the planes of the wheels on the same side, at the front and diagonally opposite on a four wheel vehicle. The measurements are processed to provide wheel toe, relative wheel plane orientation, front wheel offset and front and rear wheel setback relative to the vehicle frame to assist in damage assessment.

Abstract: A wheel alignment apparatus (10) for measuring the toe angles of the wheels (42) of a vehicle such that the wheels (42) may be properly aligned, including vehicles whose rear axle (20) and front axle (22) are of unequal lengths. The wheel alignment apparatus (10) of the present invention includes at least one light beam source (14) for emitting a beam of light (24) toward a photosensor (12). The light beam (24) produces currents at each end of the photosensor (12), the currents then being measured and processed by a signal processor (16) to determine the impinging angle of the light beam (24). Each of the light beam sources (14) and the photosensors (12) are attached to the respective wheels (42) with connecting apparatuses, or heads (18). The photosensor (12) is a lateral photocell for receiving at least a portion of the emitted light beam (24) on a continuous active area (30). The signal processor (16) includes an Analog-to-Digital (A-D) converter (94) for data analysis and storage.

Abstract: A four wheel automotive vehicle is placed in a horizontal plane and is capable of being tilted in a direction perpendicular to a lengthwise direction of the car body. After determining a reference position of each front wheel in a transverse direction, perpendicular to the lengthwise direction of the automotive vehicle, the plane is tilted at an angle proportional to a cant of a road in the transverse direction. While rotating synchronously the front and rear wheels in the same direction as they would rotate when the automotive vehicle moves forward, a toe angle of each rear wheel and a deflection from the reference position of each front wheel, in the transverse direction, are measured. Observing the measurements of toe angle and deflection, the toe angles of the rear wheels are adjusted totally to a desired toe angle until the deflection becomes almost zero. Thereafter, observing the measurements of toe angle, the toe angles of the front wheels are adjusted totally to a desired toe angle.

Abstract: A wheel alignment system uses head units attached to each of the four wheels of an automotive vehicle. Angle measurements are taken using light sources and light sensors. Pitch sensors measure the pitch of the head units with respect to a horizontal plane. The head units are connected to the left and right front wheels of the automotive vehicle. The pitch information is used to compensate for errors in left and right cross-toe measurements between the left and right front wheels of the automotive vehicle.

Abstract: A structured light scanning system observes, interprets and provides structural feature size, position and movement data in automotive service equipment applications where such feature characteristics must be determined either preliminary to or ultimately for measurement of quantities affecting automotive performance, such as tire/rim assembly balance, runout and alignment or brake surface planarity and smoothness.

Abstract: A device and method to align the wheels of motor vehicles. A beam of collimated light from a low power visible laser is split into two generally parallel beams by a partially transmitting mirror and a series of plane front surface mirrors positioned in front and along side the vehicle being serviced. The two beams are reflected from a set of plane mirrors attached to the rims of the wheels to be aligned. The vertical and horizontal angles of each of the wheel-mounted mirrors are set by calibrated lead-screws to cancel the angular displacement of the wheels expected when the wheels are properly aligned. The reflected beams are imaged through a large aperture beam combiner on a common viewing screen. Correct toe-in and camber settings are indicated when the laser beams reflected from the wheel-mounted mirrors overlap at the center of the viewing screen.

Abstract: A wheel alignment measurement apparatus comprises six identical measuring heads to be arranged on the wheels of the vehicle and evaluation means. Four measuring heads are mounted at the four wheels of the vehicle. Two additional measuring heads are mounted on the measuring heads of the front wheels by means of rigid bars so as to be disposed in front of the vehicle. Each measuring head includes (a) a structure for detecting vertical angles in the form of a pendulum structure suspended freely movable about an axle and including a radiation source 6 emitting a vertical beam, (b) a structure for detecting horizontal angles including an outside radiation source arranged in the facing measuring head and emitting a horizontal beam, and (c) only one sensor line 9 in the area of intersection of the horizontal and vertical beams for contact-free detection of horizontal and vertical angles. An evaluation unit calculates the alignment data from the outputs of the sensor lines.

Abstract: An automotive vehicle wheel alignment system uses a light source and a linear CCD to measure angles. A mask having a slit through which light from the light source is projected onto the surface of the linear CCD is interposed between the light source and the linear CCD. A microprocessor controls the light source and the linear CCD and uses an output from the linear CCD to calculate an angle between the light source and the linear CCD. The microprocessor uses a search algorithm to locate the center of the image projected on the linear CCD. Calibration data for the linear CCD is stored in an EEPROM.

Abstract: A method of aiming adjustment for headlight of automotive vehicles, which is joined with a turning test of wheels for obtaining relationship between steering wheel angles and wheel turning angles, includes steps of: detecting step for detecting side edge of a headlight or a front combination lamp while a tested vehicle is placed on a turning test station, calculating step for calculating an aberration or inclination of a tested vehicle with respect to a headlight aiming testing line in a horizontal plane, and correcting step for correcting coordinates of the aiming test according to said aberration or inclination.

Abstract: A wheel alignment system includes either four wheel mountable alignment heads or two alignment heads and two retroreflectors or two alignment heads alone together with a control console and display. A main processing unit is included in the console for performing calculations and for controlling systems function control components communications sequences. Each console function control component includes its own controller. The control console further includes a CRT display module and optional voice instruction and printer output modules. A bar code reader is available for quick specifications entry. Communications and decision making instructions are downloaded from the controller in each console function control component to the main processing unit at initialization. Communication between the heads and the console is accomplished either through the use of conducting cords or infrared transmission and reception.

Abstract: A method for determining wheel alignment of an automobile includes the initial step of clamping the chassis of the automobile in a measuring bench. After determining a centerline and datum plane for the automobile, a measuring system calibrated to the centerline and datum plane projects a laser beam parallel to the centerline in the datum plane. The laser beam is movable in the datum plane and in a plane perpendicular to the datum plane. The front suspension of each front wheel hub is then lifted to the proper ride height relative to the datum plane. A measuring unit is then mounted to each front wheel hub. The measurement of the camber, caster, SAI/KPI, and toe of each wheel hub is then determined. In addition, the TOOT of the front wheel hubs are determined while the hubs are lifted. Other measurements are possible, including checking the wheel alignment of the rear wheels.

Abstract: Noncontact sensors project fanned or structured light onto the tire, while the wheel is rotated, to illuminate at least two contour lines on the surface of the tire. the contour lines are read by video cameras, positioned offset from the optical plane of the structured light, to allow triangulation in determining the spatial position of the contour lines. Radially equivalent points are selected from each contour line by an algorithm which ignores the effects of any raised lettering on the tire sidewalls. Control of the video cameras and processing of the video data is performed by parallel processor-based computer system coordinated by sequencer circuit.

Abstract: An optical toe/track measurement system includes a pair of toe gauge assemblies respectively mountable on the two wheels at one end of a motor vehicle and a pair of track scale assemblies respectively mountable on the other two wheels of the vehicle. Each toe gauge assembly includes an elongated tubular housing having toe and track projection systems for respectively projecting toe and track light beams from the opposite ends of the housing, the track beam being projected coaxially with the housing onto the track scale on the same side of the vehicle, while the toe beam is projected perpendicular to the longitudinal axis of the housing onto a scale carried by the toe gauge assembly on the other side of the vehicle. Light is supplied respectively to the two toe gauge assemblies throught two fiber optic cables from a single remote light source.

Abstract: A vehicle wheel alignment and checking apparatus for front and rear wheels in which the apparatus has active light beam projecting instruments mounted on the front wheels to project beams longitudinally and transversely between the wheels of the vehicle, passive wheel position instruments on the wheels for reflecting incident beams to the active instruments, a system of mirrors associated with the active and passive instruments and beam targets for utilizing the system of mirrors and targets to find the alignment information, and alignment data indicators responsive to the manipulation of the active instruments and responses from the passive instruments for visually revealing the alignment data and aiding in adjusting the wheels to specified alignment values.

Abstract: Proposed in accordance with the invention is a method of measuring the camber, KPI and caster wheel alignment angles in the front axle and suspension assembly of a motor vehicle without the need for recourse to a levelled surface or to any gravitation-sensing instruments for the purpose of the measurements. One front wheel at a time is measured, for which purpose the wheel is fitted with a projecting pin parallel to the wheel axle intended to support a laser beam machine which emits a beam perpendicular to the wheel axle. A screen marked with reference lines is positioned at a certain distance away from the wheel, initially in front of, and then alongside the wheel, with the direction of the reference lines corresponding to the direction of the reference plane of the vehicle.

Abstract: A wheel alignment system includes either four wheel mountable alignment heads or two alignment heads and two retroreflectors or two alignment heads alone together with a control console and display. A main process unit is included in the console for performing calculations and for controlling systems function control components communications sequences. Each console function control component includes its own controller. The control console further includes a CRT display module and optional voice instruction and printer output modules. A bar code reader is available for quick specifications entry. Communications and decision making instructions are downloaded from the controller in each console function control component to the main processing unit at initialization. Communication between the heads and the console is accomplished either through the use of conducting cords or infrared transmission and reception.

Abstract: Noncontact sensors project fanned or structured light onto the tire, while the wheel is rotated, to illuminate at least two contour lines on the surface of the tire. The contour lines are read by video cameras, positioned offset from the optical plane of the structured light, to allow triangulation in determining the spatial position of the contour lines. Radially equivalent points are selected from each contour line by an algorithm which ignores the effects of any raised lettering on the tire sidewalls. Control of the video cameras and processing of the video data is performed by parallel processor-based computer system coordinated by sequencer circuit.

Abstract: The invention relates to an arrangement for measuring wheel alignment and steering geometry in an automobile. A substantially horizontal bar is placed in front of the vehicle at right angles to its longitudinal axis. A light source displaceable along the bar emits a narrow ray of light at an angle to the bar. The vehicle front wheel to be measured is provided with a unit including at least three angle sensors of which at least one comprises a widely dimensioned light detector placed in the focal plane of an optical means. The light source on the bar is set to a position on said bar where the emitted light beam strikes the optics approximately at the center thereof. A calculating device determines the wheel alignment values with the aid of the angle sensor signals for variable positions of the wheel and the motion of the light source along the bar.

Abstract: Vehicle wheel alignment apparatus having preferred constructions in which the angle measuring components are assembled at each wheel in a unique cooperative arrangement and in which certain of the components represent existing wheel positions and other components relate the wheels in pairs so important alignment characteristics may be investigated for all wheels as well as the steerable wheels in relation to the non-steerable wheels.

Abstract: Vehicle wheel alignment apparatus having active alignment determining means operatively mounted on the steerable and non-steerable wheels so as to be substantially insensitive to mechanical distortion of the vehicle wheels and operable in combination with wheel run out compensation means to produce wheel alignment results of improved accuracy, and utilizing the improved arrangement of alignment apparatus for supplying information which can be used for computing the important angular relationship of the wheels to a vehicle reference.