Asked — Edited

Recycling Dead Servos Into Mini H-Bridge Controllers

This is just a record of my little discovery and experiment for other novices to this field.

I had a near DOA mini servo from a pan/tilt setup I had ordered with my EZ-Robot kit, the servo worked but made lots of noise and finally stalled out after a short use. Upon disassembly I could not see any gear related issues, so I dug further and found that some glue sealing the wound wiring in place on the motor's armature had broken off and jammed the little motor internally. Since that was not repairable I decided to experiment with some stuff I saw online and took the controller board and attached it to a larger (relatively) DC motor that I had kicking around.

As many of you probably already know, a servo is just a DC motor with a mini H-Bridge controller circuit, a reduction gear mechanism and a variable potentiometer for position feedback. So if you have a dead servo or two kicking around due to stripped gears your can still use the motor and circuit, or just the circuit with another small DC motor already in use in your toy or device you want to robotize.

No need to toss out stripped servos:) I am thinking of converting a USB rocket launcher I have into EZ-Robot mode, without having to do any heavy-ish modding to install servos.

Just be aware that the servo circuits are only good for lower wattage DC motors. Ratings probably depend on the servo they came out of.

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Yes, I am amused by simple things:P

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Nice find! I have a bunch of servos with stripped gears, and didn't even think to do this, I wonder how well it would work with those small 3vdc motors you see with things like the Tamiya grarboxes... Thanks for posting this!