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[cookietran]

Ok, so I finally got the mech's legs built. I was playing with the sequence software, and part of it was doing some extended duration single leg stands (kinda have to to play with poses of course :P) So, I was just wondering how hot some of your servos get. One of the knee servos in the leg got up to 150 degrees F (measured by an IR thermometer). Is that normal? Or would that fall under the "abuse of a servo"? They are HSR5990TG servos, so I am assuming that if I was really bad with them their thermal cutout would kick in.

[jwatte]

For hobby servos, I have no idea whether they even have a thermal cut-off, or if they just let you run them until they die?

150F (about 65C I think?) on the actual core/windings of the servos is borderline, I would say. The Dynamixels are set to cut off at 80 degrees C, and I generally lower that to 70C. Different motors are differently robust to overheating; the more efficient the motor (the narrower the air gap, and the more expensive the motor, generally) the less robust it is to overheating. So, if the hobby servos have cheap Chinese brushed motors, they may be able to take a bit more abuse.

If the manufacturer doesn't publish a data sheet with the appropriate ratings in it, you'll have to experiment yourself. If you push it to 65C and let it cool down and it still works, then that's probably alright, and if you know that you won't see more load than this, then that's your envelope!