Vehicle service system optical target assembly calibration

Patent metadata

Field	Value
Publication number	US-9544545-B2
Application number	US-201414464534-A
Country	US
Kind code	B2
Filing date	Aug 20, 2014
Priority date	Sep 28, 2005
Publication date	Jan 10, 2017
Grant date	Jan 10, 2017

Abstract

A machine vision vehicle wheel alignment system for acquiring measurements associated with a vehicle. The system includes at least one imaging sensor having a field of view and at least one optical target secured to a wheel assembly on a vehicle within the field of view of the imaging sensor. The optical target includes a plurality of visible target elements disposed on at least two surfaces in a determinable geometric and spatial configuration which are calibrated prior to use. A processing unit in the system is configured to receive at least two sets of image data from the imaging sensor, with each set of image data acquired at a different rotational position of the wheel assembly around an axis of rotation and representative of at least one visible target element on each of the two surfaces, from which the processing unit is configured to identify said axis of rotation of the wheel assembly.

First claim

The invention claimed is:

1. A machine vision vehicle wheel alignment system for acquiring measurements associated with a vehicle, comprising:
at least one imaging sensor having a field of view;
at least one optical target secured to the vehicle within the field of view of said at least one imaging sensor, said optical target having a plurality of visible target elements disposed on at least two surfaces in a determinable geometric and spatial configuration;
a processing unit configured to receive image data representative of at least one visible target element on each of said two surfaces from said at least one imaging sensor, and to process said received image data together with data establishing said determinable geometric and spatial configuration of said plurality of visible target elements on said at least two surfaces, to determine at least one measurement associated with said vehicle.

2. The machine vision vehicle wheel alignment system of claim 1 wherein said at least two surfaces are planar surfaces, are non-planar surfaces, are smoothly curved surfaces, are angled surfaces, or are facets of a dimensionally stable object.

3. The machine vision vehicle wheel alignment system of claim 1 wherein said at least two surfaces are dimensionally stable.

4. The machine vision vehicle wheel alignment system of claim 1 wherein said target elements on said first surface are arranged in a predetermined geometric and spatial configuration relative to each other;
wherein said target elements on said second surface are arranged in a predetermined geometric and spatial configuration relative to each other;
wherein said processing unit is configured to determine at least one measurement associated with said vehicle by utilizing said predetermined geometric and spatial relationships between said target elements on said first surface, together with said predetermined geometric and spatial relationships between said target elements on said second surface, to establish a geometric and spatial configuration of said first surface relative to said second surface.

5. The machine vision vehicle wheel alignment system of claim 1 wherein said processing unit is further configured to establish said determinable geometric and spatial configuration of said plurality of visible target elements before determining said at least one measurement associated with said vehicle.

6. The machine vision vehicle wheel alignment system of claim 5 wherein said processing unit is configured to establish said determinable geometric and spatial configuration of said plurality of visible target elements from a plurality of images of said visible target elements, each of which is acquired at a different position or view of said optical target.

7. The machine vision vehicle wheel alignment system of claim 1 wherein said data establishing said determinable geometric and spatial configuration of said plurality of visible target elements further establishes a geometric and spatial configuration of said at least two surfaces on which said visible target elements are disposed.

8. The machine vision vehicle wheel alignment system of claim 7 wherein said geometric and spatial configuration of said at least two surfaces is defined as the geometric and spatial configuration of one of said surfaces relative to another of said surfaces.

Assignees

• Hunter Eng Co

Inventors

• Stieff Michael T
• Dorrance Daniel R
• Golab Thomas J
• Shylanski Mark S

Classifications

• G01B11/2755 Primary

  using photoelectric detection means · CPC title

• B60R11/04

  Mounting of cameras operative during drive; Arrangement of controls thereof relative to the vehicle · CPC title

• H04N7/18 Primary

  Closed-circuit television [CCTV] systems, i.e. systems in which the video signal is not broadcast · CPC title

• G01B2210/12

  Method or fixture for calibrating the wheel aligner · CPC title

• G01B2210/14

  One or more cameras or other optical devices capable of acquiring a two-dimensional image · CPC title