dirty_d wrote:No, it doesn't respond to the input signal at the same 400Hz that its given. There is a digital impulse response low-pass filter in the ESC. But The filter is designed to work with a 50Hz input signal. When you feed it 400Hz it shifts the cutoff point upward because its based on the time between pulses. So where the cutoff freq for a 50Hz input might be 5Hz the cutoff freq for the 400Hz might be 40Hz (I see a huge difference in throttle response between hooking the ESC straight to the reciever or to my control board).
People have made much smaller quadcopters with standard ESCs at 400hz so I doubt I'll have a problem getting this to stabilize. I just use a wild ass guess for the pid values, p=800, i=0, d=-50. I think I'll try p=400, i=0, d=-160. With the i term being 0 the quad would not be able to hover level if i.e. there's more weight to one side. I'll worry about the i term after it can fly relatively stable.
dirty_d wrote:You used only PI on a quadcopter or some other project?
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