pxmlw6n2f/Gazebo_Distributed_TCP/gazebo/common/PID.hh

222 lines
7.4 KiB
C++

/*
* Copyright (C) 2012 Open Source Robotics Foundation
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
*/
#ifndef _GAZEBO_PID_HH_
#define _GAZEBO_PID_HH_
#include "gazebo/common/Time.hh"
#include "gazebo/util/system.hh"
namespace gazebo
{
namespace common
{
/// \addtogroup gazebo_common
/// \{
/// \class PID PID.hh common/common.hh
/// \brief Generic PID controller class.
/// Generic proportiolnal-integral-derivative controller class that
/// keeps track of PID-error states and control inputs given
/// the state of a system and a user specified target state.
class GZ_COMMON_VISIBLE PID
{
/// \brief Constructor, zeros out Pid values when created and
/// initialize Pid-gains and integral term limits:[iMax:iMin]-[I1:I2].
///
/// Disable command clamping by setting _cmdMin to a value larger
/// than _cmdMax. Command clamping is disabled by default.
///
/// \param[in] _p The proportional gain.
/// \param[in] _i The integral gain.
/// \param[in] _d The derivative gain.
/// \param[in] _imax The integral upper limit.
/// \param[in] _imin The integral lower limit.
/// \param[in] _cmdMax Output max value.
/// \param[in] _cmdMin Output min value.
public: PID(double _p = 0.0, double _i = 0.0, double _d = 0.0,
double _imax = 0.0, double _imin = 0.0,
double _cmdMax = -1.0, double _cmdMin = 0.0);
/// \brief Destructor
public: virtual ~PID();
/// \brief Initialize PID-gains and integral term
/// limits:[iMax:iMin]-[I1:I2]
///
/// Disable command clamping by setting _cmdMin to a value larger
/// than _cmdMax. Command clamping is disabled by default.
///
/// \param[in] _p The proportional gain.
/// \param[in] _i The integral gain.
/// \param[in] _d The derivative gain.
/// \param[in] _imax The integral upper limit.
/// \param[in] _imin The integral lower limit.
/// \param[in] _cmdMax Output max value.
/// \param[in] _cmdMin Output min value.
public: void Init(double _p = 0.0, double _i = 0.0, double _d = 0.0,
double _imax = 0.0, double _imin = 0.0,
double _cmdMax = -1.0, double _cmdMin = 0.0);
/// \brief Set the proportional Gain.
/// \param[in] _p proportional gain value
public: void SetPGain(double _p);
/// \brief Set the integral Gain.
/// \param[in] _p integral gain value
public: void SetIGain(double _i);
/// \brief Set the derivtive Gain.
/// \param[in] _p dertivative gain value
public: void SetDGain(double _d);
/// \brief Set the integral upper limit.
/// \param[in] _p integral upper limit value
public: void SetIMax(double _i);
/// \brief Set the integral lower limit.
/// \param[in] _p integral lower limit value
public: void SetIMin(double _i);
/// \brief Set the maximum value for the command.
/// \param[in] _c The maximum value
public: void SetCmdMax(double _c);
/// \brief Set the maximum value for the command.
/// \param[in] _c The maximum value
public: void SetCmdMin(double _c);
/// \brief Get the proportional Gain.
/// \return The proportional gain value
public: double GetPGain() const;
/// \brief Get the integral Gain.
/// \return The integral gain value
public: double GetIGain() const;
/// \brief Get the derivative Gain.
/// \return The derivative gain value
public: double GetDGain() const;
/// \brief Get the integral upper limit.
/// \return The integral upper limit value
public: double GetIMax() const;
/// \brief Get the integral lower limit.
/// \return The integral lower limit value
public: double GetIMin() const;
/// \brief Get the maximum value for the command.
/// \return The maximum value
public: double GetCmdMax() const;
/// \brief Get the maximum value for the command.
/// \return The maximum value
public: double GetCmdMin() const;
/// \brief Update the Pid loop with nonuniform time step size.
/// \param[_in] _error Error since last call (p_state - p_target).
/// \param[_in] _dt Change in time since last update call.
/// Normally, this is called at every time step,
/// The return value is an updated command to be passed
/// to the object being controlled.
/// \return the command value
public: double Update(double _error, common::Time _dt);
/// \brief Set current target command for this PID controller.
/// \param[in] _cmd New command
public: void SetCmd(double _cmd);
/// \brief Return current command for this PID controller.
/// \return the command value
public: double GetCmd();
/// \brief Return PID error terms for the controller.
/// \param[in] _pe The proportional error.
/// \param[in] _ie The integral error.
/// \param[in] _de The derivative error.
public: void GetErrors(double &_pe, double &_ie, double &_de);
/// \brief Assignment operator
/// \param[in] _p a reference to a PID to assign values from
/// \return reference to this instance
public: PID &operator=(const PID &_p)
{
if (this == &_p)
return *this;
this->pGain = _p.pGain;
this->iGain = _p.iGain;
this->dGain = _p.dGain;
this->iMax = _p.iMax;
this->iMin = _p.iMin;
this->cmdMax = _p.cmdMax;
this->cmdMin = _p.cmdMin;
this->pErrLast = _p.pErrLast;
this->pErr = _p.pErr;
this->iErr = _p.iErr;
this->dErr = _p.dErr;
this->cmd = _p.cmd;
this->Reset();
return *this;
}
/// \brief Reset the errors and command.
public: void Reset();
/// \brief Error at a previous step.
private: double pErrLast;
/// \brief Current error.
private: double pErr;
/// \brief Integral error.
private: double iErr;
/// \brief Derivative error.
private: double dErr;
/// \brief Gain for proportional control.
private: double pGain;
/// \brief Gain for integral control.
private: double iGain;
/// \brief Gain for derivative control.
private: double dGain;
/// \brief Maximum clamping value for integral term.
private: double iMax;
/// \brief Minim clamping value for integral term.
private: double iMin;
/// \brief Command value.
private: double cmd;
/// \brief Max command clamping value.
private: double cmdMax = -1.0;
/// \brief Min command clamping value.
private: double cmdMin = 0.0;
};
/// \}
}
}
#endif