[FTC]: DC Motor Speed

[R.C.]

What do you mean by Speed?

Mechanically you could speed up whatever mechanism by placing a larger sprocket/gear on the motor output and then placing a smaller spocket/gear on the mechanism.

Programming: I'm pretty sure you just put it to max power and that is the max speed.

The Motor only spins @ 154 RPM's, so its not extremely fast.

[ethan_orion]

We have geared up the motor to increase the speed.
Are the templates pre-programmed with max speed?
I'm still figuring out labview.

Hmm.. 154rpms. okay. Thanks

[BLAQmx]

Originally Posted by ethan_orion

Are the templates pre-programmed with max speed?

Yes they are. Notice the VI Calculate Power from Joystick. This VI has an input called throttle. The default value for throttle is 50, but in the teleopbasic template it is set to be 100; e.g. full power can be output from this VI into a Move DC Motor VI. If this input is set to be 50 only half of the full power will be output from this VI.

If you have more programming questions feel free to post them in the FTC Community site on ni.com.

[JohnFogarty]

In order to acheive max speed use large to small gear ratio because direct connecting the battery to the motor will give you the max speed of the motor.

[Rick TYler]

Originally Posted by John_1102

In order to acheive max speed use large to small gear ratio because direct connecting the battery to the motor will give you the max speed of the motor.

If I remember correctly, last year the TETRIX folk warned against gearing up drivetrains using the 12-volt motors after a series of gearhead failures. They recommended either direct-driving or gearing down the motors. This was a recommendation for drivetrains, so I'm not sure if they make similar suggestions for other applications. We broke three gearheads last year on a geared-up drivetrain and the problems went away when we changed to a slower design.

I know a lot of teams are planning on heavily gearing up wheels to shoot balls this year (including our own FTC team) and I expect it to work pretty well since the intertia of a whiffle ball is a lot lower than that of an entire robot. Just in case, we have a stock of spare 12-volt motors and a design that lends itself to rapid swaps.

[JohnFogarty]

I do remember that, we blew 2-3 motors ourselves even one at nationals. It really depends on what you need the motor to do. Like if all you want to speed up is a wheel then it shouldn't be too much of a problem.

[Richard Wallace]

Originally Posted by John_1102

I do remember that, we blew 2-3 motors ourselves even one at nationals. It really depends on what you need the motor to do. Like if all you want to speed up is a wheel then it shouldn't be too much of a problem.

Whether it is a problem will depend on the size of the wheel and the function it performs. A large traction load on a big wheel could easily overheat a geared-up motor. That is why it is much more common practice to gear down.

[JohnFogarty]

The thing i find funny is at the end of last year we took apart one of our broken motors and they are geared down to the slowest speed possible.