Quote:
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Originally Posted by Rickertsen2
torque output=(Kt(Vin-speed*Kv))/r
where:
Kt is the torque voltage constant in newton-meters per amp
Kv is the speed CEMF constant in volts per radian per sec
r is the armature resistance in ohms
Vin is the input voltage in volts
if you plug this into our friend newton's second law and solve for speed vs time for a particular voltage input, you will find that when there are no other forces in the system(ie motor is spinning freely), speed will be porportional to voltage input(after time for acceleration/decelleration is allowed).
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Well the trick there would be that we don't have an actual DC signal going into the motor. I'm relatively certain that the inductance of the motor will have an effect on the square wave going into the motor. And I'm too lazy to try to figure out the transfer function of a square wave with variable duty cycle, so I was just going to make a Simulink model of the whole electro-mechanical system and be done with it. Assuming I can find data on the frequency of the PWM output of the Vics, that is.
EDIT: This link claims the frequency is 120Hz.
http://www.enigmaindustries.com/links.htm
Also, Victor 885? have these always been around or are we getting new Vics this year? I'll grant you they're overpowered for our applications, though.