US Patent 7369222 Wheel aligner measurement module attachment system

In a vehicle alignment system an optical sensing mechanism is structurally coupled to a vehicle supporting lift for movement in unison with the lift so that the field of view of the sensing mechanism encompasses a wheel of a vehicle positioned on the lift during lift movement. Sensing modules may be selectively placed so that they are in correspondence with the vehicle wheel base. Modules may be deployed to extend outwardly from the lift, for viewing the wheel during an alignment procedure, or retract to a adjacent the lift for stowing. A protective cover extends above the sensing modules in the retracted position.