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Topic: Velocity Profile in a DC motor (Read 985 times) previous topic - next topic

teddybearfer00

Hi!! I need to program a 3rd degree velocity profile so i can move a DC motor, which should reach its maximum velocity in 2 seconds. The thing is that I have no idea on how to do that... My first guess is to program the profile directly into the arduino and then conect my outputs to a DAC and then to the motor... but how do i program a profile??  :smiley-sad-blue:

MarkT

If you can program the profile as a function from milliseconds to output duty-cycle, you'll be halfway there...
[ I won't respond to messages, use the forum please ]

Grumpy_Mike

Quote
I need to program a 3rd degree velocity profile so i can move a DC motor,

That sounds very specific, is it an assignment question?

A lot depends on the step response of the motor. Then you need to integrate that into the control you can generate.
In effect you produce a profile which applies power to the motor in a step wise manner. This is either in terms of supplying it with a varying voltage or a varying PWM signal and changing that signal over the time of the profile. The more parts you split up this profile into the closer will be your control.
It is a long time since I did servo control and it wasn't called a 3rd degree velocity profile in my day but I suspect that this is the critical damped state.

Bill_Kerr


3rd degree velocity profile


Hi teddybear

This site may help about smoothstep
http://sol.gfxile.net/interpolation/index.html#c5

It mentions 3rd power, which maybe what you are looking for?

Regards  Bill

Don't you just hate ONE D 10 T problems?

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