Sensorless back_emf speed controller

[vamfun]

With the power of the Crio and the Jag's we have the tools to read the back_emf voltage and build a PID controller to hold a reference speed and manage the speed acceleration profile.

This would make a nice off season control project for team 599 and would be usefull for all teams if it works.

Questions:
1)Has anyone already done this with a CIM and FRC controllers?

2)Will FRC open up for 2010 the JAG Controller Area Network (CAN) interface to use the full motor contol features available...eg current sensing, encoder input , a/d etc of the internal ARM? If so, then this project would not be as usefull.


Project ground rules :
1) use the existing 2009 JAG constraints.
2)Use the jag limit switches for momentary motor shut off to make back_emf voltage measurements
3)use Crio a/d to measure back_emf voltage and do PID control
4)implement with both Labview and Winriver
5)CIM 01 motor
6)Make project results transparent to all FRC teams
7)Possibly make a joint FRC team project with those interested.

Concepts are well known and used in model train,rc etc motor control.

Advantages... eliminate need for encoders on every motor to do speed control. Just a few for position measurement.

I know we have lots of motor experts out there so I'd like to hear from you.