Fault tolerant wheel alignment head and system

Abstract

A sensing head and system utilizes fault tolerant design and self-diagnosis. Alternative operation modes are provided when one or more functional modules or components fail. Unique designs provide redundant system resources. Self-diagnoses and tests are provided to isolate and identify sources of malfunctions.

1 . A sensing head for use in a wheel alignment system, comprising:
 one or more functional modules, each of which is configured to perform a function usable in obtaining measurements for calculating wheel alignment parameters of a vehicle, wherein the functional modules include at least one of:
 a wireless communication interface module configured to communicate in a wireless manner with a computer system or a companion sensing head attached to the vehicle; 
 a spatial relationship sensing module configured to measure a spatial relationship between the sensing head and the companion sensing head; 
 an image sensing module configured to producing image data representing an image taken of a target associated with a vehicle wheel; and 
 an illumination module configured to illuminate the target; 
   a data processor configured to calculate the measurements based on data received from the one or more functional modules;   wherein the one or more functional modules provide operation redundancy by utilizing at least one of:   providing multiple sets of illumination devices in the illumination module, wherein at least one set is independent from another set and is configured to illuminate the target independently;   providing multiple paths for communication with the computer system using the wireless communication module, wherein at least one of the paths is different from another path;   providing multiple sets of illumination devices to the spatial relationship sensing module, wherein at least one set is independent from another set and is configured to independently generate a signal to the companion sensing head; and   providing multiple processing units for implementing the data processor, wherein each processing unit is configured to independently perform the functions of the data processor.   
   
   
       2 - 29 . (canceled)