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DeveloperPermalink Reply by Doug Weibel on September 3, 2010 at 6:20pm

Quad's have been successfully built using 20ms frame rate ESC's. There is no point in running your PID loop any faster than your ESC's frame rate.

There are ESC's available that will handle much higher frame rates, and these will provide better performance in a quad.

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Permalink Reply by Guillaume Helle on September 4, 2010 at 10:16am

I have Turnigy plush 30A...

In fact it seems everybody try to compute PID and change motor speed as fast they can but i am not sure of the result...

I think it is suffisant to change the motor speed between 10ms and 20ms...

But how verify it? ;-)

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Permalink Reply by Paul Rene Joergensen on October 21, 2010 at 2:10am

It would be interesting to slow down our main loop to let's say 10ms and 20ms and see how it affects stability. The IMU code should run as fast as possible or as fast as the ADC's can run.

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Permalink Reply by Pizza on November 4, 2010 at 3:13am

is faster sampling rate better? will there be aliasing problem?

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DeveloperPermalink Reply by Doug Weibel on November 4, 2010 at 7:40am

certainly there can be a sampling rate issue if you sample too slow. It is not readily apparent in all of our code what the sampling rate is. In some instances the actual sampling rate is set in an interrupt vector or elsewhere, and the "sampling" in the main code is just collecting averages from the lower level code.

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