Tuesday, January 22, 2008

Tips for Modifying Servos

OK so here I am making my own tips/instructions for modifying a servo. This is my favorite and the most accurate way.

  • To modify the servo replace the pot with two 2.2K precision ( 1% -2% tolerance) resistors
  • If precision resistors are not available but you have resistors with the same color-band , get a multimeter and measure which resistors have the closest resistance. Then pick the two resistors that have the closest resistance and use those.
  • Be careful when desoldering the potentiometer ( if it has leads connected to the PCB) . If the potentiometer has wires coming out of it and not only leads, solder the resistors to the wires and not directly to the circuit board. ( photo courtesy of Seatlle Robotics Club)
  • When you cut the wires off the potentiometer ( if it has wires) , cut it so that the potentiometer can be reused later on, you might need it in one of your projects.
  • After you have modified the servo circuitwise, try to remove the pot from the inside of the servo. If the potentiometer is hard to remove , DO NOT USE FORCE, and just leave it in there.
  • Also, when using servos for locomotion. One servo has to be going clockwise and one has to be going counterclockwise for the vehicle to move forward, right? So on one of the servos , reverse the wires to the motor so that way , both motors will get the same pulse to go forward.
  • When you modify the output gear for continuous rotation saw it carefully, making sure not to damage the gear teeth, and use a file to smooth it out.
  • Before putting the servo back together , make sure all the gears can move and that nothing is stuck in between the gears
  • Last tip: Be careful when opening a servo. Open the screws carefully and don't lose gears, as well as do not touch the grease too much.

1 comment:

Mike Shimniok said...

Great blog you have. I went ahead and linked to you so my miniscule trickle of traffic to my 'bot blog may send a hit or two your way. :D