Quote:
Originally Posted by EricVanWyk
I'm not saying that CAN will let you do things that are impossible now, I'm just hoping it lowers the ((entrance)) bar for some of the fundamentals.
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Most of the features that the CAN bus allows us to do are easily doable now.
The speed (Voltage) control mode, is the mode we are using through PWMs.
The Analog position input (Potentiometer)
has been done by almost everyone using an arm (PID control)
The Encoder position control
Can be done this year, use a PID controller and have your setpoint be a # of ticks
Limit switches - Digital input,
if(input && (abs(speed)/speed) == limitDirection) motor.set(0.0);
else motor.set(speed);
Though, the real advantage of using CAN is that the Jags handle the monitoring, and control internally.
Which can provide the fastest response possible in a closed loop.
(At least with the motors & controllers we can use)
And any faults can be read by the RIO,
ex: does that red slow blink mean the limit switch has been triggered or is the jaguar dead?
Conditions like: over-current, under voltage (ie 6v from battery), limit switch, or over temperature; can easily be read from like the driverstation LCD instead of guessing.
Also having access to all the motors variables (current, voltage, torque, speed) without having to put in a large coil of wire for a current sensor is nice.
http://www.luminarymicro.com/products/mdl_bdc.html
BD-BDC-DS-01 Datasheet for Brushed DC Motor Control Module