Method For Optical Chassis Measurement

• US 20080174789A1
• Filed: 11/16/2006
• Published: 07/24/2008
• Est. Priority Date: 12/29/2005
• Status: Active Grant

• Current Assignee: Beissbarth Automotive Testing Solutions GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Uffenkamp, Volker, Nobis, Guenter
• Granted Patent: US 7,535,558 B2
• Time in Patent Office: Days
• US Class Current: 356/615
• CPC Class Codes: G01B 11/2755 using photoelectric detection means
• CPC Class Codes: G01B 2210/20 Vehicle in a state of translatory motion
• CPC Class Codes: G01B 2210/28 Beam projector and related sensors, camera, inclinometer or other active sensing or projecting device

Abstract

The invention relates to a method for optically measuring a chassis at a testing station. According to said method, radiation that is reflected by a surface structure of a vehicle, comprising at least one wheel (5) and a surrounding bodywork section, is detected by a measuring device with the aid of appropriate sensors, and at least the wheel plane and the wheel centre point are determined by an evaluation of the positional data obtained by means of the detected radiation. To achieve a reliable, precise measurement of the chassis in a simple operation, the surface structure of at least the vehicle bodywork section and at least the wheel is scanned, over its entire surface or at least by any two lines that record both the wheel and the bodywork, using a laser beam (12) that is emitted by the measuring device (10), and at least two surface profiles are obtained from the scanned surface structure as characteristic structures.

Claims

1. A method for optical chassis measurement at a testing station, in which radiation reflected against a surface structure of a vehicle, including at least one wheel and a chassis opening surrounding it, is detected by a measuring device by means of a corresponding sensor system and, through evaluation of position data acquired from the detected radiation, at least the wheel plane and the wheel center point are determined,

wherein the surface structure of at least one opening of the chassis and of at least the wheel is scanned over its area—

or at least along any two lines that intersect both the wheel and the chassis—

by means of a laser beam emitted by the measuring device and as characteristic structures, at least two surface profiles from the scanned surface structure are acquired, and at points in which the profile lines intersect, for example, with the wheel rim edge or other rotationally symmetrical contours on the wheel and with the wheel opening of the chassis, the spatial positions of characteristic surface points are determined as position data based on which the chassis data of interest are ascertained.

2. The method as recited in claim 1,

wherein the spatial position of surface points scanned for the detection of the surface structure is determined by means of spatial polar coordinates, which are defined by the horizontal and vertical direction of the emitted laser beam and by the distance between the surface point and the receiving sensor for the reflected laser beam of the measuring device in accordance with the principle of a travel time measurement and/or phase difference measurement.

3. The method as recited in claim 1,

wherein the laser beam is mechanically deflected for sequential scanning or the scanning is executed through the triggering of a stationary system.

4. The method as recited in claim 1,

wherein in order to determine the wheel plane, the wheel center point, and, where applicable, the chassis opening surrounding the wheel, a multitude of surface points in the form of a 3-D aggregate of points are consulted, but at least three points are consulted at which two surface profiles intersect with rotationally symmetrical contours of the wheel.

5. The method as recited in claim 1,

wherein the load state of the wheel is determined based on the edge of the wheel opening, while the track and camber are determined based on the wheel plane and wheel center point.

6. The method as recited in claim 1,

wherein in the scanning, significant surface features on the wheel such as the valve, hole pattern, and labeling as well as dirt and/or a damaged region are detected and based on these surface features, a wheel rim eccentricity is detected while the wheel is rotating and taken into account in subsequent evaluation.

7. The method as recited in claim 1,

wherein the measurement is carried out as the vehicle is driven past and travel direction data are acquired based on a detection of the movement direction of chassis surface structures.