Abstract: A wheel balancer is provided that includes a shaft adapted for receiving a wheel/tire assembly, the shaft having a longitudinal axis and being rotatable about the axis so as to rotate a wheel/tire assembly removably mounted thereon, a rotation sensor for measuring rotation of the shaft about its longitudinal axis, a vibration sensor operatively connected to the shaft for measuring vibrations resulting from imbalance in the wheel/tire assembly and a motor operatively connected to the shaft for rotating the shaft about its longitudinal axis, thereby to rotate the wheel/tire assembly. A control circuit is also provided for controlling the application of power to the motor. The wheel balancer also includes an assembly for measuring runout of the rim of the wheel/tire assembly, the control circuit being responsive to a rim runout measurement signal to apply power to the motor such that the wheel/tire assembly rotates at a slow, controlled speed during measurement of the rim runout.

Abstract: An integrated automotive repair shop network is designed to greatly enhance the efficiency and quality of diagnostic and repair work performed in an automotive repair shop. The network employs a data entry terminal for the entry of routine customer information into a shop management system, including the identification of the vehicle to undergo diagnosis or repair. The shop management system is configured to generate an appropriate repair order. Computerized diagnostic and repair devices linked through the network to the shop management system are configured to access the customer information contained in the repair orders, as well as to extract relevant technical specifications, service bulletins, parts listings, and prior services records from interconnected information databases.

Abstract: A wheel balancer and method of mounting a wheel/tire assembly on a wheel balancer are provided. The wheel balancer includes a shaft adapted for receiving a wheel/tire assembly, the shaft having a longitudinal axis and being rotatable about the axis so as to rotate a wheel/tire assembly removably mounted thereon, a rotation sensor for measuring rotation of the shaft about its axis, a vibration sensor operatively connected to the shaft for measuring vibrations from imbalance in the wheel/tire assembly and a motor operatively connected to the shaft for rotating the shaft about its longitudinal axis, thereby rotating the wheel/tire assembly. A control circuit and manual input are also included. The control circuit controls the application of power to the motor.

Abstract: A wheel balancer is provided that includes a shaft adapted for receiving a wheel/tire assembly, the shaft having a longitudinal axis and being rotatable about the axis so as to rotate a wheel/tire assembly removably mounted thereon. The wheel balancer also includes a rotation sensor for measuring the rotation of the shaft about its longitudinal axis, vibration sensor operatively connected to the shaft for measuring vibrations resulting from imbalance in the wheel/tire assembly and a motor operatively connected the shaft for rotating the shaft about its longitudinal axis, thereby rotating the wheel/tire assembly. A control circuit for controlling the application of power to the motor is also included. The control circuit controls the application of power to the motor to rotate the wheel/tire assembly and to actively hold the wheel/tire assembly at desired positions.

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: A system for measuring vehicle alignment angles has a plurality of sensor elements for mounting to wheels of a vehicle to be aligned. The system uses the sensor elements to measure various angles such as steer ahead angle and toe, and the system also has a display for displaying information to a user and a memory for storing operating instructions for the system. Operating instructions are stored in the memory for determining from compensation measurements taken at a minimum of first and second longitudinally displaced positions whether the toe parameter of two wheels falls outside a predetermined toe range, and whether the steer ahead angle of the vehicle falls within a predetermined range. The operating instructions stored in the memory further include instructions responsive to the toe parameter falling outside the toe range to control the system to display to the user information indicative of the need to adjust the toe parameter before taking additional compensation measurements.

Abstract: A three-dimensional wheel alignment display system (10) and method includes a processor (12) and display unit (14) interconnected with a motor vehicle wheel alignment system (18) adapted to determine vehicle wheel angular relationships such as camber, caster, and toe. The processor of the display system is configured to manipulate portions of a digital three-dimensional model (100) of at least one motor vehicle wheel and associated suspension components to correspond to the angular relationships determined by the wheel alignment system.

Abstract: Steering wheel lash and suspension play are checked by comparing predefined movements of the steering wheel and the road wheels. A steering wheel fixture adapted to be mounted to the steering wheel particularly facilitates the steering wheel lash determination. Quickly mountable and removable road wheel angle sensors also facilitate the method.

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: A vehicle alignment and inspection system is provided which uses context sensitive information from several sources to enable the user/operator to achieve a more efficient alignment or inspection than previous systems. Features include digital photographs responsive to point-and-click operations by the operator, drop-down menus allowing direct access to specific operations, a database of tools and parts required for the job, and a "smart" alignment procedure.

Abstract: The system includes camber and toe sensing apparatus, a memory for storing camber and toe specifications for a plurality of vehicles, and a computer. The computer compares sensed camber and toe with corresponding specification of camber and toe, selects a shim from a plurality of standard shims and a shim orientation to attempt to correct both camber and toe in accordance with a preset priority, and determines residual camber error and residual toe error that would result from installation of the shim at the selected orientation. The user may select another orientation that attempts to correct both camber and toe in accordance with the manually requested desired priority. The user works with the system interactively, and can request various error priorities or allocation on the fly. The residual errors resulting from the selected priorities are displayed in substantially real time to provide visual feedback.

Abstract: A vehicle wheel alignment apparatus includes wheel alignment sensors for obtaining wheel alignment data, including camber, and devices for measuring wheel offset distances. A controller compensates the measured wheel offset distances for the camber of the corresponding wheels. Ride height sensors are included for measuring the ride height of the vehicle at the wheels, and the controller also uses the ride height to compensate the wheel offset distances. Ride height is similarly compensated for camber by the controller. The body angle of the vehicle is obtained from the wheel offset measurements and the wheelbase of the vehicle. The body angle is used to compute dog track angles and correct those angles by applying the body angle to the individual toe angles of the reference axle. Axle offsets are computed and used in front axle cradle adjustment if applicable. The body angle is also used to eliminate the effect of wheel offsets from setback angle calculations.

Abstract: Vehicle wheel alignment apparatus includes a storage device for storing vehicle wheel alignment angle specifications, wheel alignment sensors, and ride height sensors. A controller is responsive to the acquired wheel alignment angle data and to the measured ride height for determining whether, taking into consideration the vehicle ride height, a measured wheel alignment angle falls within specifications. Apparatus for diagnosing vehicle wheel alignment and suspension problems also includes a jack for vertically moving the body of the vehicle with respect to the wheels to temporarily change the ride height of the vehicle. The controller is responsive to changes in measured wheel alignment angles with changes in measured ride height to diagnose vehicle alignment and suspension problems.

Abstract: A sideslip tester detects sideslip and scrub in a vehicle having a steering axle and one or more pairs of tandem axles. The sideslip tester has a runway having a measurement plate which is moved laterally with respect to its longitudinal axis as a tire of the vehicle passes over the measurement plate as a result of lateral forces acting upon the tire. A lateral movement sensor operatively connected to the measurement plate determines the amount of lateral movement of the measurement plate as the vehicle tire passes over the plate and provides an output corresponding to the amount of lateral movement measured. The sideslip tester can determine when it is presented with tandem axles. When it is presented with tandem axles, the sideslip tester will determine the scrub angle of the tandem axles to determine if they are parallel.

Abstract: The brakes of a two-axle vehicle are tested by weighing the vehicle and measuring the braking forces for both axles to determine the actual ratio of front axle braking force to total braking force. The deceleration applied to the vehicle is determined from the weight of the vehicle and the applied braking forces. A nominal preferred value of the ratio of front axle braking force to total braking force is calculated from the determined deceleration and the measured weight of the vehicle. The nominal preferred value varies from test to test with both the actual deceleration and the vehicle weight. For each test, upper and lower limits for the acceptability of the actual ratio of front axle braking force to total braking force are set based upon the computed nominal preferred value. These limits move from test to test with the computed nominal preferred value. The nominal preferred value, the movable limits, and the actual ratio are displayed to the user on a CRT screen.

Abstract: A plate brake tester for testing the adequacy of the brakes of a vehicle, particularly suited for testing the brakes of multi-axle vehicles, includes weight bearing plates suitably sized to receive thereon wheel/tire assemblies of a vehicle as the vehicle is driven over the plates. The plates have sensors associated therewith for sensing not only the brake force applied by each wheel/tire assembly, but also for directly sensing the dynamic weight of the wheel/tire assembly on each plate during braking. The adequacy of the brakes is determined from the brake force and the directly sensed dynamic weight. At least some of the sensors are preferably dual axis load cells, each dual axis load cell having one output representing vertical force applied to that plate and having a second output representing horizontal force applied to that plate, the horizontal force being the braking force from the wheel/tire assembly disposed on that plate.

Abstract: The brakes of a two-axle vehicle are tested by weighing the vehicle and measuring the braking forces for both axles to determine the actual ratio of front axle braking force to total braking force. The deceleration applied to the vehicle is determined from the weight of the vehicle and the applied braking forces. A nominal preferred value of the ratio of front axle braking force to total braking force is calculated from the determined deceleration and the measured weight of the vehicle. The nominal preferred value varies from test to test with both the actual deceleration and the vehicle weight. For each test, upper and lower limits for the acceptability of the actual ratio of front axle braking force to total braking force are set based upon the computed nominal preferred value. These limits move from test to test with the computed nominal preferred value. The nominal preferred value, the movable limits, and the actual ratio are displayed to the user on a CRT screen.

Abstract: A sideslip meter includes first and second parallel runways. The first runway has a measurement plate movable laterally with respect to the direction of travel of the vehicle along the runway as a tire of said vehicle passes over the measurement plate. A lateral movement sensor senses the amount of lateral movement of the measurement plate and provides a corresponding output signal. First and second switches are spaced along the first runway. Each switch is actuated by the passage of a vehicle tire so that passage of the vehicle causes first one and then the other of the switches to be actuated. A display is provided for displaying information concerning lateral movement of the measurement plate. A control circuit determines vehicle velocity and vehicle direction from the actuations of the first and second switches and inhibits the display if the velocity is too fast or too slow, or if the vehicle is going backwards over the runways.

Abstract: The brakes of a two-axle vehicle are tested by weighing the vehicle and measuring the braking forces for both axles to determine the actual ratio of front axle braking force to total braking force. The deceleration applied to the vehicle is determined from the weight of the vehicle and the applied braking forces. A nominal preferred value of the ratio of front axle braking force to total braking force is calculated from the determined deceleration and the measured weight of the vehicle. The nominal preferred value varies from test to test with both the actual deceleration and the vehicle weight. For each test, upper and lower limits for the acceptability of the actual ratio of front axle braking force to total braking force are set based upon the computed nominal preferred value. These limits move from test to test with the computed nonimal preferred value. The nominal preferred value, the movable limits, and the actual ratio are displayed to the user on a CRT screen.

Abstract: A wobble run-out compensation system includes a compensation plate mountable with respect to a vehicle wheel. First and second manually operable adjusting members allow for independently adjusting the orientation of the compensation plate in first and second orthogonal planes, an adjustment in one plane not affecting the orientation of the plate in the other plane. The orientation of the compensation plate in each of the first and second planes is electronically sensed and substantially continuously displayed on an electronic display as that orientation is being adjusted so that the user is able to observe changes on the electronic display in the orientation of the compensation plate as manual adjustments are made.