Snap-on Inc.

Snap-on Technologies, Inc.

Steve L Glickman

David A Jackson

George Michael Gill

Eric F Bryan

Patrick O'Mahony

Michael J Robb

Manjula Gururaj

Stephen K Rigsby

Patrick Brendan O'MAHONY

A method is provided for positioning a free-standing fixture relative to a vehicle, using a visual aligner system for imaging vehicle-mounted targets with reference image sensors and processing the resultant images. Embodiments include calculating locations of the vehicle-mounted targets, calculating a location of a reference point on the vehicle, and determining a longitudinal line along a longitudinal axis of the vehicle. A location of a center of the fixture and an axis of the fixture is then calculated based on an image of one of the targets obtained by a remote image sensor attached to the fixture. The fixture is positioned by adjusting the fixture relative to the vehicle to achieve a desired position or orientation of the fixture based on the performed comparison steps and angle calculations.

Method for use with an optical aligner system for positioning a fixture relative to a vehicle

In a machine vision system utilizing computer processing of image data, an imaging module incorporates the image sensor as well as pre-processing circuitry, for example, for performing a background subtraction and/or a gradient calculation. The pre-processing circuitry may also compress the image information. The host computer receives the pre-processed image data and performs all other calculations necessary to complete the machine vision application, for example, to determine one or more wheel alignment parameters of a subject vehicle. In a disclosed example useful for wheel alignment, the module also includes illumination elements, and the module circuitry provides associated camera control. The background subtraction, gradient calculation and associated compression require simpler, less expensive circuitry than for typical image pre-processing boards. Yet, the pre-processing at the imaging module substantially reduces the processing burden on the host computer when compared to machine vision implementations using direct streaming of image data to the host computer.

Gradient calculating camera board

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. In so doing, the processing means relates the geometric characteristics and positional interrelationships of certain known elements of the target with the geometric characteristics and positional interrelationships of corresponding elements in the viewed images and calculates the position and/or alignment of the objects to which the targets are attached.

Method and apparatus for calibrating cameras used in the alignment of

Growing community of inventors

Los Gatos, CA, United States of America

Steve L Glickman