Tetrix Servos 2013

[Bryce Paputa]

Yeah, one of these servos is not going to cut it. Lets assume that the 4 bar linkage is 6 inches long, and that 2kg~5lb, that would require 30lb-in, or 480oz-in, of torque to hold, plus the weight of the mechanism, plus the torque to accelerate it, plus inefficiencies like friction. This is well above the stall torque, you'd need some where between 16:1 and 4:1 of reduction depending on the servo used, which would probably mean that you would need a continuous rotation servo which has even less torque (not to mention that it would be insanely slow). A NXT motor might be a tiny bit better, but not much. Why can't a DC motor be used?

[immukage]

Thanks for the replies guys. What if we used 2 of these servos? Still not gonna cut it?

As for DC Motors, all motor controllers are out of stock atm and won't be in stock until after our competition so we're trying to make do with what we have.

[Bryce Paputa]

Maybe, you'd still need a reduction, but it would be less. There are other teams near you that you could possibly borrow one from, right? If not, the Michigan FTC season just "ended" and you might be able to get one from here.

[magnets]

If you put a heavy weight on the end of an arm on a servo, and you set an angle, the servo will overshoot past the setpoint, and then oscillate and never settle. For powering heavy stuff, try to avoid servos. Instead, you could try to make it easier for the servo with some surgical tubing to help pull the heavy arm up, so the servo has an equal load lifting and putting down the box. Again, you will need to do the math to see if it's possible.