forked from Archive/PX4-Autopilot
110 lines
2.4 KiB
C
110 lines
2.4 KiB
C
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#include "pid.h"
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#include <px4/attitude_estimator_bm/matrix.h> //TODO: move matrix.h to somewhere else?
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void pid_init(PID_t *pid, float kp, float ki, float kd, float intmax,
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uint8_t mode, uint8_t plot_i)
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{
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pid->kp = kp;
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pid->ki = ki;
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pid->kd = kd;
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pid->intmax = intmax;
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pid->mode = mode;
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pid->plot_i = plot_i;
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pid->count = 0;
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pid->saturated = 0;
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pid->sp = 0;
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pid->error_previous = 0;
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pid->integral = 0;
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}
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void pid_set_parameters(PID_t *pid, float kp, float ki, float kd, float intmax)
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{
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pid->kp = kp;
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pid->ki = ki;
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pid->kd = kd;
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pid->intmax = intmax;
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// pid->mode = mode;
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// pid->sp = 0;
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// pid->error_previous = 0;
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// pid->integral = 0;
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}
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//void pid_set(PID_t *pid, float sp)
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//{
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// pid->sp = sp;
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// pid->error_previous = 0;
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// pid->integral = 0;
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//}
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/**
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*
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* @param pid
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* @param val
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* @param dt
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* @return
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*/
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float pid_calculate(PID_t *pid, float sp, float val, float val_dot, float dt)
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{
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/* error = setpoint - actual_position
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integral = integral + (error*dt)
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derivative = (error - previous_error)/dt
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output = (Kp*error) + (Ki*integral) + (Kd*derivative)
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previous_error = error
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wait(dt)
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goto start
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*/
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float i, d;
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pid->sp = sp;
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float error = pid->sp - val;
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if (pid->saturated && (pid->integral * error > 0)) {
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//Output is saturated and the integral would get bigger (positive or negative)
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i = pid->integral;
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//Reset saturation. If we are still saturated this will be set again at output limit check.
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pid->saturated = 0;
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} else {
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i = pid->integral + (error * dt);
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}
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// Anti-Windup. Needed if we don't use the saturation above.
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if (pid->intmax != 0.0) {
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if (i > pid->intmax) {
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pid->integral = pid->intmax;
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} else if (i < -pid->intmax) {
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pid->integral = -pid->intmax;
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} else {
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pid->integral = i;
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}
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//Send Controller integrals
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// Disabled because of new possibilities with debug_vect.
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// Now sent in Main Loop at 5 Hz. 26.06.2010 Laurens
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// if (pid->plot_i && (pid->count++ % 16 == 0)&&(global_data.param[PARAM_SEND_SLOT_DEBUG_2] == 1))
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// {
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// mavlink_msg_debug_send(MAVLINK_COMM_1, pid->plot_i, pid->integral);
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// }
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}
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if (pid->mode == PID_MODE_DERIVATIV_CALC) {
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d = (error - pid->error_previous) / dt;
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} else if (pid->mode == PID_MODE_DERIVATIV_SET) {
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d = -val_dot;
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} else {
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d = 0;
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}
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pid->error_previous = error;
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return (error * pid->kp) + (i * pid->ki) + (d * pid->kd);
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}
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