PIDFFController.c

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

void PIDFF_modelTune(PIDBase* self,
                const PT1Model* const model,
                float w)
{
        self->Kp = model->alpha*w*w;
        self->Ki = model->alpha/(w*w*w);
        self->Kd = model->alpha*w - model->beta;
        self->Kt = self->Tf = 0;

        self->model.alpha = model->alpha;
        self->model.beta = model->beta;
        self->model.betaa = model->betaa;
}

void PIDFF_tune(PIDBase* self, float w)
{
        self->Kp = 2*w;
        self->Ki = w*w;
        self->Kd = self->Kt = self->Tf = 0;
}

void PIDFF_wffStep(PIDBase* self, float Ts, float error, float ff)
{
        //Perform windup test if automatic mode is enabled.
        if (self->autoWindup == 1)
        {
                self->windup = (self->internalState > self->output) && (error>0);
                self->windup = (self->windup) ||
                                ((self->internalState < self->output) && (error<0));
        }
        else
        {
                //Experimental
                //self->windup = ((self->windup >0) && (error>0)) ||
                //              ((self->windup <0) && (error<0));
        }

        //Proportional term
        self->internalState += self->Kp*(error-self->lastError);
        //Integral term
        //Disabled if windup is in progress.
  if (!self->windup) self->internalState += self->Ki*Ts*error;
  //Derivative
  self->internalState += self->Kd*1/Ts*(error-2*self->lastError+self->llastError);
        //Feed forward term
        self->internalState += ff - self->lastFF;
        //Set final output
        self->output = self->internalState;

        if (self->autoWindup == 1)
        {
                self->output = sat(self->output,-self->outputLimit, self->outputLimit);
        }

        self->llastError = self->lastError;
        self->lastError = error;
        self->lastRef = self->desired;
        self->lastFF = ff;
}

void PIDFF_dwffStep(PIDBase* self, float Ts, float error, float ff, float ds)
{
        //Perform windup test if automatic mode is enabled.
        if (self->autoWindup == 1)
        {
                self->windup = (self->internalState > self->output) && (error>0);
                self->windup = (self->windup) ||
                                ((self->internalState < self->output) && (error<0));
        }
        else
        {
                //Experimental
                //self->windup = ((self->windup >0) && (error>0)) ||
                //              ((self->windup <0) && (error<0));
        }

        //Proportional term
        self->internalState += self->Kp*(error-self->lastError);
        //Integral term
        //Disabled if windup is in progress.
  if (!self->windup) self->internalState += self->Ki*Ts*error;
  //Derivative
  self->internalState += self->Kd*(self->lastDerivative - ds);
        //Feed forward term
        self->internalState += ff - self->lastFF;
        //Set final output
        self->output = self->internalState;

        if (self->autoWindup == 1)
        {
                self->output = sat(self->output,-self->outputLimit, self->outputLimit);
        }

        self->lastDerivative = ds;
        self->llastError = self->lastError;
        self->lastError = error;
        self->lastRef = self->desired;
        self->lastFF = ff;
}