Kilian's Robot Shop of Horrors - 06/14/2002

We started out inspecting the PIC-SERVO PC boards. We didn't find anything that we considered unuseable. But we marked a couple spots.

Then we worked on my (Jeff's) motor test bed. It is a motor from the Earth Explorer, a smaller DC motor with encoder to be used as an encoder, an Open Source Motor Controller driver board and a PIC prototype board to be used as a controller. We mounted the big motor and drilled an aluminum plate to mount the small motor. (Actually it got drilled twice before it was useable.) We mounted the small motor and coupled the two motors with a piece of rubber hose.

Then we powered up the big motor. Alan used the "finger tach" to get an accurate RPM reading. It was amazing. He sat there motionless for about 2 minutes while his finger was thumping away. Then he proclaimed "8 revolutions per second". So we hooked up the scope and decided it was actually 11 revolutions per second. But that's a whole lot closer that I could have guessed. The calculator cyphered out 694 RPM.

We finished off with a long discussion on robot navigation. This was prompted by a video tape I made of the Earth Explorer driving through some trees.

-Jeff

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Oh yeah, those PC boards to mail out...

Alan decided we should visually inspect the PIC-SERVO boards so he can get them mailed out. (Before he leaves the country...)

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Jeff's motor test bed

Jeff has these parts for a motor test bed.	Carefully drilling the motor mounting holes.	Time for the big boy.	No problem cutting right through.
Whoops! That's not even close.	So the second one gets a pilot hole.	Still a chance to screw it up.	Close enough. Screwing in the motor.
Alan is using the finger tach.	This is what the scope says.	Mr. calculator confirms about 700 RPM.	These motors only draw 1/4 amp at 25 volts. Better than I thought.
The finished test bed.

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