DE3531459

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 processing 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.