Nigel et al ,

I think SERVO is the ONLY way to go . Point Taken . I'd better get started on that . Any useful links on PID control of DC motors , encoder construction (ready made ones are not common) , and other updates to that effect would be greatly appreciated . And by the way , Nigel , (no Radio Shacks down here in India (futaba) , though i wish they were..... )

And panic , it is an engineering marvel , your design , :wink: , but I cannot use any components / ideas that you suggest because of the prohibitively high prices.

And the answer to the question by Panic , it is planned to be installed in a normal road - use car (suzuki hatch-back) . It would be expected to negotiate all obstacles that normal usage in city traffic would put forth .

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