CVehicleVelCmd.h

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/* +------------------------------------------------------------------------+
   |                     Mobile Robot Programming Toolkit (MRPT)            |
   |                          http://www.mrpt.org/                          |
   |                                                                        |
   | Copyright (c) 2005-2017, Individual contributors, see AUTHORS file     |
   | See: http://www.mrpt.org/Authors - All rights reserved.                |
   | Released under BSD License. See details in http://www.mrpt.org/License |
   +------------------------------------------------------------------------+ */
#pragma once

#include <mrpt/utils/CSerializable.h>
#include <mrpt/utils/CConfigFileBase.h>
#include <string>

namespace mrpt
{
namespace kinematics
{
/** Virtual base for velocity commands of different kinematic models of planar
 * mobile robot.
 * \ingroup mrpt_kinematics_grp */
class CVehicleVelCmd : public mrpt::utils::CSerializable
{
        DEFINE_VIRTUAL_SERIALIZABLE(CVehicleVelCmd)
   public:
        CVehicleVelCmd();
        CVehicleVelCmd(const CVehicleVelCmd& other);
        virtual ~CVehicleVelCmd();
        CVehicleVelCmd& operator=(const CVehicleVelCmd& other);

        /** Get number of components in each velocity command */
        virtual size_t getVelCmdLength() const = 0;
        /** Get textual, human-readable description of each velocity command
         * component */
        virtual std::string getVelCmdDescription(const int index) const = 0;
        /** Get each velocity command component */
        virtual double getVelCmdElement(const int index) const = 0;
        /** Set each velocity command component */
        virtual void setVelCmdElement(const int index, const double val) = 0;
        /** Returns true if the command means "do not move" / "stop". \sa setToStop
         */
        virtual bool isStopCmd() const = 0;
        /** Set to a command that means "do not move" / "stop". \sa isStopCmd */
        virtual void setToStop() = 0;
        /** Returns a human readable description of the cmd */
        std::string asString() const;

        /** Parameters that may be used by cmdVel_limits() in any derived classes.
         */
        struct TVelCmdParams
        {
                /** Max. linear speed (m/s) [Default=-1 (not set), will raise exception
                 * if needed and not set] */
                double robotMax_V_mps;
                /** Max. angular speed (rad/s) [Default=-1 (not set), will raise
                 * exception if needed and not set] */
                double robotMax_W_radps;
                /** Min. radius of curvature of paths (m) [Default=-1 (not set), will
                 * raise exception if needed and not set] */
                double robotMinCurvRadius;

                TVelCmdParams();
                /** Load any parameter required by a CVehicleVelCmd derived class. */
                void loadConfigFile(
                        const mrpt::utils::CConfigFileBase& cfg,
                        const std::string& section);
                void saveToConfigFile(
                        mrpt::utils::CConfigFileBase& c, const std::string& s) const;
        };

        /** Scale the velocity command encoded in this object.
        * \param[in] vel_scale A scale within [0,1] reflecting how much should be
        * the raw velocity command be lessen (e.g. for safety reasons,...).
        * \param[out] out_vel_cmd
        *
        * Users can directly inherit from existing implementations instead of
        * manually redefining this method:
        *  - mrpt::kinematics::CVehicleVelCmd_DiffDriven
        *  - mrpt::kinematics::CVehicleVelCmd_Holo
        */
        virtual void cmdVel_scale(double vel_scale) = 0;

        /** Updates this command, computing a blended version of `beta` (within
        * [0,1]) of `vel_cmd` and `1-beta` of `prev_vel_cmd`, simultaneously
        * to honoring any user-side maximum velocities.
        * \return The [0,1] ratio that the cmdvel had to be scaled down, or 1.0 if
        * none.
        */
        virtual double cmdVel_limits(
                const mrpt::kinematics::CVehicleVelCmd& prev_vel_cmd, const double beta,
                const TVelCmdParams& params) = 0;
};

}  // End of namespace
}  // End of namespace