6V motor overcurrent
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I was wondering whether any reckless roboteer has tried running the diddyborg 6V motors at 9 or 12V? I read that a motor can run a 300-400% over current for perhaps a minute? We're doing the 7m straight line speed test at PiWars which at 6V is taking around 49s - it'd be nice to do it in half that - as long as we didn't fry anything.
Thinking about it now - the motors are supposed to do 60rpm - so is 7 seconds per metre a bit on the slow side? Do you have any timings for the diddyborg when built as per your instructions? I appreciate ours is carrying a little more weight...
piborg
Wed, 11/18/2015 - 17:40
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Temporarily running DiddyBorg over-voltage
For short periods of time running the motors at a higher voltage should be okay.
I would recommend trying 9V first to make sure everything works as intended.
60 RPM is the rate the wheels should turn at when the robot is off the ground.
In that sense it is like the theoretical top speed of a car.
In reality the weight of the robot will make them turn slower when he is actually moving forward.
From experience the speed DiddyBorg moves on a solid surface is about 0.12 ~ 0.15 m/s.
A quick calculation would suggest an average DiddyBorg would take about 52s to travel a 7m distance.
He will tend to move quickest when the batteries are freshly charged.
We have run DiddyBorgs over-voltage quite happily before, the speed improvement is obvious.
Also bear in mind twice the power will not be quite twice the speed.
Remember not to run the motors at higher voltages for too long, otherwise they may overheat and stop working.
Additionally running motors like this will reduce their lifespan.
I would recommend only running the motors like this on special occasions :)
Alternatively we are now selling a faster DiddyBorg that uses 12V 100 RPM motors:
https://www.piborg.org/diddyborg/rededition
You can also get the motors on their own here (you would need 6 of the same):
https://www.piborg.org/diddyborg/rededition/motor-wheel
richardandaliso...
Mon, 11/23/2015 - 14:38
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success
Many thanks Piborg, we tried using 9V and can't smell any burning so far ;)
I think we'll leave it there for this year - although I do quite fancy trying some whizzier motors (with encoders) when we build our next robot.