Today, we tried to set the coefficients of our PID algorithm. In order to do this, we used the Ziegler-Nichols method. The first step is to set the integral and the derivative gains to zero. Then, we increase the value of the proportional gain, to obtain the control loop oscillating constantly. Unfortunatly, we didn’t succeed in obtaining the special value of P (proportional gain). It seemed we had still some bugs on the Kalman filter. Samuel and Axel tested again the good working of the Kalman filter (we had to change some coefficients of the Kalman since we put the card on the Copter), and fixed it.
Samuel made a basic program, in order to change easily the PID coefficients, while the Copter is running : we can now observe the effects of the changes in live.
We worked also on some improvements of the code: for the STM32 and for the Kanade algorithm, to prepare the future work & debug. For example, the UART was configured at 1 000 000 bps, so the STM32 had only 72 instructions to perform between each UART interrupt. Since we only send 150 packets/s (~20 bytes), 57600 bps speed would be fine, and more convenient.
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