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By craftykate
We are going through the inventor's kit workbook and have gotten to circuit 5B - Remote Controlled Robot and it's not behaving the way it should. It turns when it's supposed to go forward and goes forward when it's supposed to turn. I checked 1,000 times that all our wires are hooked up the way the book says to (version 4.0a, so it's the corrected version) and we never modified the code. Is there a way to test that the motor driver is working properly? It's the motor driver that came with the inventor's kit. Not sure what to do here, any help appreciated.
By craftykate
Thanks, reversing BIN1 and BIN2 did the trick, but I don't know enough about the motor driver to know if it's a problem with the driver or a problem with the program. The program looks good and seems to make sense with the way it was supposed to be hooked up so I'm not sure what was wrong. I'm happy the vehicle works the way it's supposed to now, but I haven't learned WHY it was backwards. I'd love to learn more. Is there a basic motor driver test somewhere?
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By DanV
I can't really tell, but glossing over the code and diagram, I'm guessing that the two motors have to drive in opposite directions (one CW and the other CCW) in order to drive the thing forward, since they are mounted on either side of the 'car'.
I'm unsure if that was taken into account in the final documentation or code.

What I DO know is that since the intent is for the motors to drive the same direction to go forward and opposite direction to turn, and your description of what the thing really did, the only solution was to change that somewhere, either I the code or the wiring - simplest way is to change the wiring.

basic motor driver test - I don't know of such a thing (doesn't mean it doesn't exist).
By craftykate
That's a really good point about the motors needing to be opposite since they are mounted on either side of the car. The program doesn't seem to take that into account as far as I can tell. Thank you!!