CMPackWalkMC.h

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//-*-c++-*-

//This class is ported from Carnegie Mellon's 2001 Robosoccer entry, and falls under their license:
/*=========================================================================
    CMPack'02 Source Code Release for OPEN-R SDK v1.0
    Copyright (C) 2002 Multirobot Lab [Project Head: Manuela Veloso]
    School of Computer Science, Carnegie Mellon University
  -------------------------------------------------------------------------
    This software is distributed under the GNU General Public License,
    version 2.  If you do not have a copy of this licence, visit
    www.gnu.org, or write: Free Software Foundation, 59 Temple Place,
    Suite 330 Boston, MA 02111-1307 USA.  This program is distributed
    in the hope that it will be useful, but WITHOUT ANY WARRANTY,
    including MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  -------------------------------------------------------------------------
    Additionally licensed to Sony Corporation under the following terms:

    This software is provided by the copyright holders AS IS and any
    express or implied warranties, including, but not limited to, the
    implied warranties of merchantability and fitness for a particular
    purpose are disclaimed.  In no event shall authors be liable for
    any direct, indirect, incidental, special, exemplary, or consequential
    damages (including, but not limited to, procurement of substitute
    goods or services; loss of use, data, or profits; or business
    interruption) however caused and on any theory of liability, whether
    in contract, strict liability, or tort (including negligence or
    otherwise) arising in any way out of the use of this software, even if
    advised of the possibility of such damage.
  =========================================================================
*/

#ifndef INCLUDED_CMPackWalkMC_h
#define INCLUDED_CMPackWalkMC_h

#include "MotionCommand.h"
#include "Geometry.h"
#include "OldKinematics.h"
#include "Path.h"
#include "Shared/get_time.h"
#include "OutputCmd.h"
#include "Shared/LoadSave.h"

//! A nice walking class from Carnegie Mellon University's 2001 Robosoccer team, modified to fit this framework, see their <a href="../CMPack_license.txt">license</a>
/*! Moves the feet through a looping path in order to walk - default parameters use
 *  a walk low to the ground so you don't walk over the ball.
 *
 *  There are around 50 parameters which control the walk - these are
 *  loaded from a file and can modify almost every aspect of the the
 *  gait.  It's a binary file format, I recommend using our Walk Edit
 *  menu to edit the parameters in real time and get immediate
 *  feedback.  It's a tricky job to find a good set of parameters.
 *
 *  And then, once you have it walking, there's a whole different
 *  problem of actually moving at the speed that's requested.  That's
 *  what the calibration parameters do - map the requested target
 *  speed to the command to pass to the engine so the resulting motion
 *  will hopefully match what you asked for.
 *
 *  You'll probably want to take a look at the setTargetVelocity()
 *  function to control the direction of the walk.
 *
 *  This class is in some dire need of some cleanup - we (Tekkotsu)
 *  didn't write it, have none the less hacked around and added stuff on top
 *  of it.  So pardon the mess, unless you're feeling ambitious to
 *  write your own ;)
 *
 *  This portion of the code falls under CMPack's license:
 *  @verbinclude CMPack_license.txt
 */
class CMPackWalkMC : public MotionCommand, public LoadSave {
public:
  typedef SplinePath<vector3d,float> splinepath; //!<for convenience
  typedef HermiteSplineSegment<vector3d,float> spline; //!<for convenience

  //! holds state about each leg's path
  struct LegWalkState {
    LegWalkState() : airpath(), air(0), cyc(0) {} //!< constructor
    spline airpath; //!< the path to follow
    bool air; //!< true if in the air
    float cyc; //!< % (0,1) of how far along the path we are
  };
  
  //! holds parameters about how to move each leg
  struct LegParam {
    LegParam() : neutral(), lift_vel(), down_vel(), lift_time(0), down_time(0) {} //!< constructor
    vector3d neutral; //!< defines the "neutral" point of each leg - where it is in midstep
    vector3d lift_vel; //!< give the velocities to use when raising the paw
    vector3d down_vel; //!< give the velocities to use when lowering the paw
    double lift_time; //!< the time (as percentage of WalkParam::period) in the cycle to lift (so you can set different offsets between the paws)
    double down_time; //!< the time (as percentage of WalkParam::period) in the cycle to put down (so you can set different offsets between the paws)
  };

  //! holds more general parameters about the walk
  struct WalkParam {
    WalkParam() : body_height(0), body_angle(0), hop(0), sway(0), period(0), useDiffDrive(0), sag(0), reserved() {} //!< constructor
    LegParam leg[4]; //!< a set of LegParam's, one for each leg
    double body_height; //!< the height to hold the body (mm)
    double body_angle; //!< the angle to hold the body (rad - 0 is level)
    double hop;  //!< sinusoidal hop amplitude
    double sway; //!< sinusoidal sway in y direction
    int period; //!< the time between steps
    int useDiffDrive; //!< if non-zero, diff-drive style turning is used instead of rotational turning
    float sag; //!< the amount to sagging to account for when a foot is lifted
    float reserved; //!< just live with it
  };

  //! holds information to correct for slippage, non-idealities
  struct CalibrationParam {
    CalibrationParam(); //!< constructor, sets calibration matricies to identity

    //! symbolic way to refer to each of the directions
    enum dimension_offset {
      forward, //!< forward (x)
      reverse, //!< backward (-x)
      strafe,  //!< sideways (y)
      rotate,  //!< spin (z/a)
      NUM_DIM  //!< number of directions we calibrate for
    };

    float f_calibration[3][11]; //!< matrix of calibration parameters; 3 columns for f,s,r speeds, 2 columns for abs s,r speeds, 1 gabor function, 1 squared planar speed, 3 columns for f*r,s*f,r*s, and 1 column for offset
    float b_calibration[3][11]; //!< matrix of calibration parameters; 3 columns for f,s,r speeds, 2 columns for abs s,r speeds, 1 gabor function, 1 squared planar speed, 3 columns for f*r,s*f,r*s, and 1 column for offset

    float max_accel[NUM_DIM]; //!< maximum achievable acceleration, 0 for infinite (mm/s^2)
    float max_vel[NUM_DIM]; //!< maximum achievable velocity (mm/s)
  };

  //! constructor
  CMPackWalkMC(const char* pfile=NULL);

  virtual void start(); //!< sends an activate LocomotionEvent
  virtual void stop();  //!< sends a deactivate LocomotionEvent

        //! Posts a LocomotionEvent. Also forces an output frame setting wheel velocities to zero; needed because if we remove a motion command there may be nothing left to zero the velocities.
        virtual void zeroVelocities();

  virtual int updateOutputs(); //!< calculates current positions of the legs or speeds of the wheels
  
  //! Returns true if we are walking. This modified isDirty allows the AIBO to slow down to a stop rather than stopping immediately.
  virtual int isDirty();
  
  //! Will prune if we've taken the requested number of steps.
  virtual int isAlive() { return step_count != 0; }

  virtual unsigned int getBinSize() const;
  virtual unsigned int loadBuffer(const char buf[], unsigned int len, const char* filename=NULL);
  virtual unsigned int saveBuffer(char buf[], unsigned int len) const;
  virtual unsigned int loadFile(const char* filename);
  virtual unsigned int saveFile(const char* filename) const;

  //! returns current velocity we're trying to go
  const vector3d& getTargetVelocity() { return target_vel_xya; }
  //! returns the velocity we're actually moving (subject to clipping at max_accel_xya), doesn't reflect value of getPaused()...
  const vector3d& getCurVelocity() const { return vel_xya;}
  //! returns the time at which we started traveling along the current vector, in milliseconds
  unsigned int getStartTravelTime() { return travelTime; }
  //! returns the amount of time we've been traveling along the current vector, in milliseconds
  unsigned int getTravelTime() { return get_time()-getStartTravelTime(); }

  //! set the direction to walk
  /*! @param dx forward velocity (millimeters per second)
   *  @param dy left velocity (millimeters per second)
   *  @param da counterclockwise velocity (radians per second) */
  void setTargetVelocity(double dx,double dy,double da);
  
  //! set the direction to walk
  /*! @param dx forward velocity (millimeters per second)
   *  @param dy left velocity (millimeters per second)
   *  @param da counterclockwise velocity (radians per second)
   *  @param time (seconds) duration to walk before stopping and posting a status event; time will be 
   *  rounded to the nearest step time. (This is internally converted to number of steps) */
  void setTargetVelocity(double dx,double dy,double da,double time);
  
  //! recalculates the target velocity so steps are of a given length to achieve the specified displacement in @a n steps
  /*! @param dx length of displacement in millimeters along body's x axis
   *  @param dy length of displacement in millimeters along body's y axis
   *  @param da amount to turn in radians, counter-clockwise viewed from above
   *  @param time (seconds) duration in which to do the displacement (thus controls velocity); time will be 
   *  rounded to the nearest step time. (This is internally converted to number of steps)
   *
   *  @see setTargetVelocity() */
  void setTargetDisplacement(double dx, double dy, double da, double time);

  //! returns remaining steps (#step_count) (negative means infinite)
  int getRemainingSteps() const { return step_count; }

  
  float getStepThreshold() const { return step_threshold; } //!< returns the step threshold -- see #step_threshold
  void setStepThreshold(float st) { step_threshold=st; } //!< sets the step threshold -- see #step_threshold
  
  void setPaused(bool p) { isPaused=p; } //!< if set to true, will stop moving
  bool getPaused() const { return isPaused; } //!< if is true, we aren't moving
  void setHeight(double h) { wp.body_height=h; } //!< sets WalkParam::body_height of #wp
  double getHeight() { return wp.body_height; } //!< gets WalkParam::body_height of #wp
  void setAngle(double a) { wp.body_angle=a; } //!< sets WalkParam::body_angle of #wp
  double getAngle() { return wp.body_angle; } //!< gets WalkParam::body_angle of #wp
  void setHop(double h) { wp.hop=h; } //!< sets WalkParam::hop of #wp
  double getHop() { return wp.hop; } //!< gets WalkParam::hop of #wp
  void setSway(double h) { wp.sway=h; } //!< sets WalkParam::sway of #wp
  double getSway() { return wp.sway; } //!< gets WalkParam::sway of #wp
  void setPeriod(long p) { wp.period=p; } //!< sets WalkParam::period of #wp
  long getPeriod() { return wp.period; } //!< gets WalkParam::period of #wp
  void setSlowMo(float p) { slowmo=p; } //!< sets #slowmo
  float* getSlowMo() { return &slowmo; } //!< gets #slowmo

  //!used to specify value for #acc_style
  enum AccelerationStyle_t {
    CALIBRATION_ACCEL, //!< use the acceleration specified by the calibration parameters
    INF_ACCEL,         //!< ignore calibration acceleration (attempt infinite acceleration)
    DEFAULT_ACCEL      //!< reference the value of Config::motion_config::walk_acceleration
  };
  virtual void setAccelerationStyle(AccelerationStyle_t acc) { acc_style=acc; } //!< sets #acc_style
  virtual AccelerationStyle_t getAccelerationStyle() const { return acc_style; } //!< returns #acc_style

#ifdef TGT_HAS_LEGS
  //! returns the current leg position of leg @a i
  const vector3d& getLegPosition(LegOrder_t i) const { return legpos[i]; }
#endif

  struct WalkParam& getWP() { return wp; }; //!< returns the current walk parameter structure
  struct CalibrationParam& getCP() { return cp; }; //!< returns the current walk calibration parameter
  
  //! takes current leg positions from WorldState and tries to match the point in the cycle most like it
  void resetLegPos();

  static const float MAX_DX; //!< maximum forward velocity, for setTargetDisplacement
  static const float MAX_DY; //!< maximum sideways velocity, for setTargetDisplacement
  static const float MAX_DA; //!< maximum angular velocity, for setTargetDisplacement
#ifdef TGT_HAS_WHEELS
  static const float OPTIMAL_DA; //!< optimal angular velocity for Create odometry in setTargetDisplacement
#endif
  
  float getMaxXVel() const { return MAX_DX; } //!< more portable than directly accessing #MAX_DX
  float getMaxYVel() const { return MAX_DY; } //!< more portable than directly accessing #MAX_DY
  float getMaxAVel() const { return MAX_DA; } //!< more portable than directly accessing #MAX_DA

  static const vector3d max_accel_xya; //!< maximum acceleration of x, y, and a velocity

 protected:
  //! holds current joint commands
  OutputCmd cmds[NumOutputs][NumFrames];

  //! converts @a in to calibration parameters and multiplies through the calibration matrix
  static void applyCalibration(const float mat[3][11], const vector3d& in, vector3d& out);

 protected:
  //! does some setup stuff, calls loadFile(pfile)
  void init(const char* pfile);

  bool isPaused; //!< true if we are paused

  WalkParam wp; //!< current walking parameters (note that it's not static - different CMPackWalkMC's can have different setting, handy...
  CalibrationParam cp; //!< calibration parameters for current walk.
  LegWalkState legw[NumLegs]; //!< current state of each leg
  vector3d legpos[NumLegs]; //!< current position of each leg
  splinepath body_loc; //!< the path the body goes through while walking (?)
  splinepath body_angle; //!< the path the body goes through while walking (?)
  vector3d liftPos[NumLegs]; //!< position each of the feet was last lifted
  vector3d downPos[NumLegs]; //!< position each of the feet is next going to be set down
  
  AccelerationStyle_t acc_style; //!< lets you switch between finite or infinite acceleration models

  int step_count; //!< number of steps to take before stopping; if negative, walk forever.
  float step_threshold; //!< point in a leg's cycle where the step counter should be decremented; 0 - leg lift, .25 - mid-air, .5 - leg down, .75 - mid-ground

  double last_cycle; //!< where the walk is in it its cycle, updated at the end of each call to updateOutputs()

  vector3d pos_delta; //!< how much we've moved
  float angle_delta; //!< how much we've turned
  
  unsigned int travelTime; //!< the time of the last call to setTargetVelocity - handy to check the time we've been traveling current vector
  int time; //!< time of last call to updateOutputs() (scaled by slowmo)
  int TimeStep; //!< time to pretend passes between each call to updateOutputs() - usually RobotInfo::FrameTime
  float slowmo; //!< scales time values to make the walk move in slow motion for analysis (or fast forward)

  // tss "SmoothWalk" addition follows
  /*! The CycleOffset variable is used to ensure that each time the AIBO
   *  starts walking, it starts at the same point in the walk cycle as
   *  where it stopped. This measure is intended to decrease the amount
   *  of jerking (and hence deviation) that occurs when the AIBO starts
   *  walking forward and then suddenly stops. */
  int CycleOffset;
  /*! Each CycleOffset corresponds to a different TimeOffset once the
   *  robot starts walking again. Consider this example: the robot
   *  stops 2/3 of the way through the cycle, then starts again 1/3
   *  of the way through the cycle on the absolute clock. The time
   *  offset to advance the clock to the right part of the cycle is
   *  1/3 of a cycle, so we set TimeOffset to 1/3 cycle and add that to
   *  every clock value used in the walk code. */
  int TimeOffset;
  /*! Every time we stop, we know we'll have a new CycleOffset, and we'll
   *  need to compute a new TimeOffset. This boolean says as much. */
  bool NewCycleOffset;
// tss "SmoothWalk" addition ends

  vector3d target_disp_xya; //!< requested displacement
  vector3d vel_xya; //!< the current velocity we're moving
  vector3d target_vel_xya; //!< the velocity that was requested
  vector3d last_target_vel_xya; //!< the velocity that was last sent to motion
};

/* struct LegState{
   long attr,reserved;
   point3d pos;
   double angles[3];
   };
   
   struct HeadState{
   long attr,reserved;
   vector3d target;
   double angles[3];
   };
   
   struct BodyState{
   BodyPosition pos;
   LegState leg[4];
   HeadState head;
   }; 
*/

/*! @file
 * @brief Describes CMPackWalkMC, a MotionCommand for walking around
 * @author CMU RoboSoccer 2001-2002 (Creator)
 * @author ejt (ported)
 * @author PA Gov. School for the Sciences 2003 Team Project - Haoqian Chen, Yantian Martin, Jon Stahlman (modifications)
 * 
 * @verbinclude CMPack_license.txt
 */

#endif