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I don't know about your PID, but you better change it to cascaded P (position) and PI (velocity controller) simulate this circuit – Schematic created using CircuitLab In a first phase you do match the velocity. You do use a trajectory planner with a velocity output that ramps from 0 to target velocity. At this point the Kp of the position controller ...


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Without knowing your details on ESC voltage , power, kRPM/V, motor size, gear ratio or slot width, I made some assumptions and modelled the performance using a type II mixer used in the CD4046 PLL with results show below. The use of the 50 Hz A-B encoder is disruptive to the loop since it is the wrong phase / frequency reference. The phase control that I ...


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PID is just a mathematical idea that one can implement in many ways. IND method: \$G_{PID}(s) = K_p + K_i\frac{1}{s} + K_d s\$ Every part is independent (hence the name). ISA method: \$G_{PID}(s) = k_p \left[1 + \frac{1}{T_i s} + T_d s \right].\$ We can see that Ki and Kd are dependant of kp: \$K_i = k_p \frac{1}{T_i}\$ \$K_d = k_p T_d\$ There is a lot ...


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It's not that they are dependant in themselves. It's just that the system final response is the sum of the three actions (it also depends on the exact PID topology, the most common are a dozen). So if you first tune for P (typical) and you add some I most probably you'll have to slightly turn turn down P since I adds some control response in itself. Add to ...


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The underlined text means that adjusting one parameter, say Kp changes differently the total performance of the controlled system (=PID controller and process together) with different values of other controller parameters. You may for example find that increasing Kp a certain amount in a certain system decreases the rise time say 50%. Do not expect the ...


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I have explained operation of a PI controller in my answer to Understanding the flow of a PI Controller?. You might find it useful to read that as it gives a simple example of what happens the P and I terms in a cruise control system. *Figure 1. The classic PID control function. Source: Wikipedia - PID controller. I mentioned in my linked answer that it had ...


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The value of the error at a given point of time does not really give you insight into the derivative. If the error is constant with time (and is zero, or something other than zero) then the derivative with respect to time is zero. If it happens to be crossing zero at a given time the derivative will depend on the rate of change of the error, and could be ...


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I’m the author of the module and just came across this post. All the comments made are pretty much correct. But if you want a full description of this PID module check out the document I wrote outlining its behavior: https://github.com/paquettedavid/FPGATemperaturePIDController/blob/master/Documentation/FinalProjectReportDavidPaquette.pdf The PID module is ...


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