Patent ID: 7265821

Claim:
An apparatus for measuring the caster angle of the steering axis of a wheel assembly of a vehicle, said apparatus comprising: an image capture device; a support for mounting said image capture device for viewing a wheel mounting and steering assembly for a wheel of the vehicle when the wheel mounting and steering assembly is located adjacent the inside surface of the vehicle wheel assembly and beneath the vehicle; a light source, said light source positioned to illuminate the wheel mounting and steering assembly for the wheel viewed by said image capture device; and at least one computer-based control connected to said image capture device; said image capture device being positioned to view at least one physical feature on the wheel mounting and steering assembly adjacent the inside surface of the wheel assembly when illuminated with light from said light source and providing information concerning the position of the at least one physical feature to said control, said control including software programmed to determine the position of the physical feature from said information and to determine the caster angle of the steering axis from that position of the physical feature.