Measuring RPM for a Free-Spinning CIM
 

Hey
How can i measure the RPM of our shooter CIM if the CIM is not connected to a gearbox.

Re: Measuring RPM for a Free-Spinning CIM
 

Many teams make their own home-brew one-count-per-rev optical or magnetic sensor. A sensor like that is excellent for shooter wheel speeds, if decoded properly.

Optical: Paint half the wheel white and the other half black, and sense it with a photosensor.

Magnetic: put a pair of magnets on the wheel, 180 degrees apart, and sense it with a latching Hall sensor (US1881 works well)

There are many other configurations.

Re: Measuring RPM for a Free-Spinning CIM
 

Our team used the light sensors from 2011 and programmed a tachometer to output to the DS. By putting a piece of electrical tape on a wheel, we were able to use this as a "tick" mark in programming. Review team 358's example under Tachometer for sample code. If you are interested in this, message me and I'll help you get it set up.

Re: Measuring RPM for a Free-Spinning CIM
 

We used a photo sensor and a piece of retro reflective tape that is pretty darn accurate, we have it so that we don't shoot in autonomous until it speeds up, then when it senses a sudden drop it waits until it speeds up again, then coasts down when it senses the next Frisbee. It also lets us detect jams, and stop the motor to prevent fried motors.

Re: Measuring RPM for a Free-Spinning CIM
 

where can i get a photo sensor

Re: Measuring RPM for a Free-Spinning CIM
 

read post #3