초록 ▼

A sensor method and apparatus for an optical wheel alignment machine utilizes one or more light sources, such as lasers, to project a laser line or other shaped light onto various locations about the sidewall of a tire undergoing measurement. The sensor includes a video camera or other light respons

A sensor method and apparatus for an optical wheel alignment machine utilizes one or more light sources, such as lasers, to project a laser line or other shaped light onto various locations about the sidewall of a tire undergoing measurement. The sensor includes a video camera or other light responsive receiver and a optical system that combines the reflected laser lines into a single image that is received by the camera. The optical system also rotates one or more of the reflected laser lines so that all of the reflected portions have the same general orientation upon entering the camera. The camera outputs a video data stream that is indicative of the image. The sensor has an electronic circuit that analyzes this video data stream in real time to determine the location in the image of a preselected feature of each of the laser lines. The circuit then outputs coordinate data indicative of the location of this feature. The circuit is microprocessor-based and uses a comparator that compares the incoming video data stream with a threshold to determine, on a pixel-by-pixel basis, whether any particular pixel lies on or outside one of the laser lines received by the camera. For a pixel lying on a laser line, the comparator interrupts operation of the microprocessor which then determines the position within the image of that pixel. Once the pixel representing the preselected feature is found, the microprocessor uses that information to generate the coordinate output data.

대표청구항 ▼

In a sensor for use in a wheel alignment machine to measure the orientation of a tire on a vehicle to thereby determine one or more alignment characteristics of the vehicle, said sensor being of the type having at least one light source oriented to project shaped light onto a sidewall of the tire at

In a sensor for use in a wheel alignment machine to measure the orientation of a tire on a vehicle to thereby determine one or more alignment characteristics of the vehicle, said sensor being of the type having at least one light source oriented to project shaped light onto a sidewall of the tire at a plurality of spaced locations and a light responsive receiver oriented at a perspective angle with respect to said light source to receive an image that includes a portion of the shaped light that is reflected off the tire, with said light responsive receiver being operable to generate electrical signals indicative of the image, wherein the improvement comprises: a system of optical elements oriented relative to said light responsive receiver to provide said light responsive receiver with an optical view that includes the plurality of spaced locations of the tire, whereby portions of the shaped light that are reflected off the tire at each of the plurality of spaced locations are received by said light responsive receiver as a single image; and an electronic circuit responsive to said electrical signals to determine the location within the image of a predetermined feature of each of the reflected portions of shaped light, said circuit further being operable to generate output data representative of the locations of said predetermined features.