If you take a solid stance that, since you are not making the vehicle, some system details are not of concern to you......then your positioning system is guarenteed to fail !!

You need to be greatly concerned with such items as:

Speed with which the vehicle moves

Mass of the vehicle

Response curve between the sensing system and the vehicle motive controls

Human safety factor issues

Equipment and property saftey factor issues

Liability issues in case of critical system failure

Power supply certaincy during critical periods

Dead man shutdown under a controllable and reliable method.

Plus there are other issues too I am sure.

Michael Karas