OpenModem/bertos/algo/pid_control.h

116 lines
3.2 KiB
C

/**
* \file
* <!--
* This file is part of BeRTOS.
*
* Bertos is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
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* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*
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* this file and link it with other files to produce an executable, this
* file does not by itself cause the resulting executable to be covered by
* the GNU General Public License. This exception does not however
* invalidate any other reasons why the executable file might be covered by
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* Copyright 2008 Develer S.r.l. (http://www.develer.com/)
* -->
*
*
* \brief Proportional, integral, derivative controller (PID controller).
*
*
* \author Daniele Basile <asterix@develer.com>
*
* $WIZ$ module_name = "pid_control"
* $WIZ$ module_depends = "timer"
*/
#ifndef ALGO_PID_CONTROL_H
#define ALGO_PID_CONTROL_H
#include <drv/timer.h>
/**
* Data type for pid coefficient.
*/
typedef float pidk_t;
typedef float piddata_t;
/**
* PID context structure.
*/
typedef struct PidCfg
{
pidk_t kp; ///< Proportional term of PID control method (Gain).
pidk_t ki; ///< Integral term of PID control method (Integral Gain).
pidk_t kd; ///< Derivative of PID control method (Derivative Gain).
piddata_t i_max; ///< Max value of integral term.
piddata_t i_min; ///< Min value of integral term.
piddata_t out_max; ///< Man value of output.
piddata_t out_min; ///< Min value of output.
mtime_t sample_period; ///< Sample period in milliseconds.
} PidCfg;
/**
* PID context structure.
*/
typedef struct PidContext
{
const PidCfg *cfg;
piddata_t prev_err; ///< Previous error.
piddata_t i_state; ///< Integrator state (sum of all the preceding errors).
} PidContext;
/**
* Set Kp, Ki, Kd constants of PID control.
*/
INLINE void pid_control_setPid(PidCfg *pid_cfg, pidk_t kp, pidk_t ki, pidk_t kd)
{
pid_cfg->kp = kp;
pid_cfg->ki = ki;
pid_cfg->kd = kd;
}
/**
* Set sample period for PID control.
*/
INLINE void pid_control_setPeriod(PidCfg *pid_cfg, mtime_t sample_period)
{
pid_cfg->sample_period = sample_period;
}
/**
* Clear a pid control structure
*/
INLINE void pid_control_reset(PidContext *pid_ctx)
{
pid_ctx->i_state = 0;
pid_ctx->prev_err = 0;
}
piddata_t pid_control_update(PidContext *pid_ctx, piddata_t target, piddata_t curr_pos);
void pid_control_init(PidContext *pid_ctx, const PidCfg *pid_cfg);
#endif /* ALGO_PID_CONTROL_H */