PSatDController.c

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#include <labust/control/PSatDController.h>
#include <math.h>

void PSatD_tune(PIDBase* self, float w, float aAngle, float surge)
{
        //Check for zero surge
        if (fabs(surge) < 0.1) surge=0.1;

        self->Kp = w*w/surge;
        self->Kd = 2*w/surge;
        self->outputLimit = self->Kd*surge*sin(aAngle);

        self->Ki = self->Kt = self->Tf = 0;
}

void PSatD_dStep(PIDBase* self, float Ts, float derivative)
{
        //Proportional term
        self->internalState = sat(self->Kp*(self->desired - self->state),
                        -self->outputLimit, self->outputLimit);
        //Derivative term
  self->internalState += self->Kd*derivative;
        //Set final output
        self->output = self->internalState;

        self->lastError = (self->desired - self->state);
}