Maik Overmars / Robot_Software

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Dependencies:   HIDScope MODSERIAL QEI biquadFilter mbed

Fork of Robot_Software by Bram Jonkheer

help_functions/PID_controller.h@0:ef81b9f14f58, 2018-10-19 (annotated)

Committer:
bjonkheer
Date:
Fri Oct 19 07:50:39 2018 +0000
Revision:
0:ef81b9f14f58
Child:
1:ce487c9929dd
Set-up of the complete software for the robot

Who changed what in which revision?

UserRevisionLine numberNew contents of line
bjonkheer 0:ef81b9f14f58 1 #include "mbed.h"
bjonkheer 0:ef81b9f14f58 2
bjonkheer 0:ef81b9f14f58 3 double PID_controller(double error)
bjonkheer 0:ef81b9f14f58 4 {
bjonkheer 0:ef81b9f14f58 5 Kp = potmeter2.read()*3;
bjonkheer 0:ef81b9f14f58 6
bjonkheer 0:ef81b9f14f58 7 double u_k = Kp * error;
bjonkheer 0:ef81b9f14f58 8
bjonkheer 0:ef81b9f14f58 9 static double error_integral = 0;
bjonkheer 0:ef81b9f14f58 10 static double error_prev = error; // initialization with this value only done once!
bjonkheer 0:ef81b9f14f58 11 static BiQuad LowPassFilter(0.0640, 0.1279, 0.0640, -1.1683, 0.4241);
bjonkheer 0:ef81b9f14f58 12
bjonkheer 0:ef81b9f14f58 13 error_integral = error_integral + error * 1/samplingfreq;
bjonkheer 0:ef81b9f14f58 14 double u_i = Ki * error_integral;
bjonkheer 0:ef81b9f14f58 15
bjonkheer 0:ef81b9f14f58 16 double error_derivative = (error - error_prev)*samplingfreq;
bjonkheer 0:ef81b9f14f58 17 double filtered_error_derivative = LowPassFilter.step(error_derivative);
bjonkheer 0:ef81b9f14f58 18 double u_d = Kd * filtered_error_derivative;
bjonkheer 0:ef81b9f14f58 19 error_prev = error;
bjonkheer 0:ef81b9f14f58 20 return u_k+u_i+u_d;
bjonkheer 0:ef81b9f14f58 21 }