Alternative way of controlling brushed DC motor as stepper motor

Just came across this novel time based and simple (non PID) way to control angle of brushed DC motor:


He writes that his system works load-independent, but I guess that’s only true for linear loads. (start inertia = stop inertia)
A robot arm that lifts a weight, will almost never have linear load conditions.
Then there are varying parameters, like stiction and friction he can’t control.

I’d name it “ballpark positioning” at best…

I dunno, sounds a bit ad-hoc to me… my guess is that after many iterations on this code the author will arrive back at PID control after all :wink:
But let’s see, from the roadmap it sounds like they’re just starting and much is yet to be implemented.

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@o_lampe What you call ballpark is defined by him as Educated Guess.

Well, it’s a trained guess, since he uses a lookup table. If he’d extrapolate a function and implement real parameters it would be educated, IMHO.
I’ve made my own step/dir interface with a geared DC motor back in 2019. It kinda worked but the ATtiny44 was overwhelmed by interrupts from the encoder.
Today I’d use a MCU with hardware encoder.

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