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. Each alignment head also includes a controller which controls collection of alignment data in parallel at each head as well as serial transmission from each head to the console during discrete transmission periods as required by the main processing unit.

Vehicle wheel alignment apparatus and method

To obtain an enhanced two-dimensional image of a raised, light-reflective reflective feature (12), and its lower height surrounding background such that the contrast between them is enhanced, a line of light having a gradient profile is directed at an acute angle at the feature and its background to illuminate a strip of area thereacross. The reflectance intensity of the illuminated strip will vary in accordance with the height thereof because of the gradient intensity profile of the line of light. When the line of light is spanned across the feature and its background, the resultant image of the feature and its background, captured by spanning a linescan camera (24) thereacross, will exhibit an enhanced contrast between the feature and its background because of the greater height of the feature.

Technique for illuminating a surface with a gradient intensity line of light to achieve enhanced two-dimensional imaging

A system (10) for obtaining a three-dimensional image of a substrate (12) comprises a linescan camera (20) trained on the substrate normal to the plane of its surface to capture the image of a strip of area (S y ) running along a first axis. A reflective member (38), driven by a motor (39), spans a line of light (36) generated by a laser (30) at an angle across the surface of the substrate so each of a plurality of strips of area (S a ,S b ,S c . . . ), including the strip (S y ) imaged by the camera, is successively illuminated. A processing device (26) is coupled both to the camera (20) and to the motor (39) to synchronize them so that the camera captures the image of the strip within its field of view each time a successive one of the strips (S a ,S b ,S c . . . S y ) is illuminated. The processing device (26) further serves to process the successively captured images of the strip (S y ) within the field of view of the camera to obtain a three-dimensional image of the strip. A relative motion is imparted between the linescan camera (20) and the substrate (12) by a slide to enable a three-dimensional image of the substrate to be obtained.

3D imaging of a substrate using perpendicular scanning directions

Apparatus and methods are provided for measuring vehicle wheel alignment characteristics. According to one embodiment, during a first measurement cycle, spatial coordinates of multiple points on the wheel are obtained by positioning a vision sensor at various angular offsets relative to the wheel, the multiple points representative of samples from each of the various angular offsets. After the first measurement cycle and before the second measurement cycle, the wheel is rotated at least a partial revolution. During the second measurement cycle, spatial coordinates of multiple points on the wheel are obtained by positioning the vision sensor at various angular offsets relative to the wheel, the multiple points representative of samples from each of the various angular offsets. Finally, one or more characteristics of the wheel are determined based upon the spatial coordinates collected during the first measurement cycle and the spatial coordinates collected during the second measurement cycle.

Vehicle wheel alignment by rotating vision sensor

A sensor and method of determining the orientation of an object, such as the alignment characteristics of a tire and wheel assembly (58) mounted on a vehicle (60), includes projecting a plurality of light planes (62) from a first light projector (70) onto a tire and wheel assembly (58) to form a plurality of generally parallel illumination lines (64) on a tire (66) of the tire and wheel assembly (58), receiving a reflected image of at least some of the illumination lines (64) with a photo electric device (76) reflected from the tire (66) at an angle relative to a projecting angle of the first light projector (70), and determining a plane (57) defined by spatial coordinates from a selected point (55) located on each illumination line (64) imaged by the photo electric device (76), with the plane (57) representing the orientation of the tire and wheel assembly (58).

Non contact wheel alignment sensor and method

The three-dimensional position of a hole through a workpiece is determined using back lighting or front lighting (feature lighting) to determine the centroid of the hole's image in two-dimensional computer memory image space. The centroid determines a line of sight between the center of the hole's image and the actual center of the hole in real space. Next a crosshair lighting pattern (structured lighting) is projected onto the plane of the workpiece in the neighborhood of the hole. From the reflected crosshair pattern an equation representing the plane containing the hole is determined in image space. The intersection of the plane equation and the line of sight is computed and the three-dimensional, real space position of the hole is determined for comparision with an ideal position established during calibration.

Leonard H. Bieman

Papers

Method for spatial measurement of holes