Method and apparatus of automatically identifying faults in a machine vision measuring system

A method of detecting a fault of a machine vision measuring system that includes a target having a plurality of fiducials and stored image of the target and the fiducials, the method comprising the steps of:

• creating and storing a list of values representing detected fiducials of the target based on the image;
• comparing the detected fiducials to a plurality of values representing true fiducials of the target in a stored model of the target;
• selectively removing one or more of the detected fiducials from the list that fail to satisfy pre-determined criteria;
• generating a warning message using the machine vision measuring system when fewer than a first pre-determined number of detected fiducials remain in the list.

A computer-readable medium carrying one or more sequences of instructions for detecting a fault of a machine vision measuring system that includes a target having a plurality of fiducials and stored image of the target and the fiducials, wherein execution of the one or more sequences of instructions by one or more processors causes the one or more processors to perform the steps of:

• creating and storing a list of values representing detected fiducials of the target based on the image;
• comparing the detected fiducials to a plurality of values representing true fiducials of the target in a stored model of the target;
• selectively removing one or more of the detected fiducials from the list that fail to satisfy pre-determined criteria;
• generating a warning message using the machine vision measuring system when fewer than a first pre-determined number of detected fiducials remain in the list.

A computer-aided machine vision motor vehicle wheel alignment apparatus comprising:

• a camera that forms an image of a target and a plurality of fiducials on the target;
• a memory that stores the image formed by the camera;
• a data processor coupled to the memory and having stored instructions which, when executed by the data processor, cause the data processor to carry out the steps of:
• creating and storing a list of values representing detected fiducials of the target based on the image;
• comparing the detected fiducials to a plurality of values representing true fiducials of the target in a stored model of the target;
• selectively removing one or more of the detected fiducials from the list that fail to satisfy pre-determined criteria;
• generating a warning message using the machine vision measuring system when fewer than a first pre-determined number of detected fiducials remain in the list.