class path

cartesian-space velocities that are fixed in space.

Inheritance:

Public Fields

int np

number of points in the path

int currentPt

the most recently-reached point on the path

int targetPt

the point that the end effector is currently headed towards

double targetDist

distance to target point

int useSameTol

use same tolerances for each point?

double* tol

the position tolerance for each waypoint.

double* vTol

the velocity tolerance for each waypoint.

double* angleTol

the angular tolerance for each waypoint.

double vel

desired linear velocity

double omega

desired angular velocity

double maxAcc

maximum linear acceleration

double maxOmegaDot

maximum angular acceleration

triple* waypt

an array of waypoint positions

quaternion* orientation

an array of waypont orientations

int* stopAtPoint

an array indicating whether the end effector should stop at each waypoint (ie.

Public Methods

virtual int setVariables(const ptrList* taskParams)

sets path-specific variables from a list of task parameters.

virtual int getTargetPoint(const triple &pos, const quaternion &q, triple &targetPos, quaternion &targetQ)

returns the target position and orientation given an end effector pose

virtual void getPoint(int i, triple &pos, quaternion &q)

returns the world-space pose of the i'th waypoint

virtual void modifyEndpointPoseAndPath(triple &pos, quaternion &q, triple &tpos, quaternion &tq)

a hook to allow derived classes to modify the pose of the point returned by getPoint

virtual void modifyVelocityCommand(triple &v, triple &omega)

a hook to allow derived classes to modify the velocity command computed by computeVel()

virtual void setNumPoints(int n, int useSameTol)

resizes the arrays for storing path information.

Inherited from genericPath:

Public Fields

int pathNum

int endPtNum

int reachedStart

int reachedEnd

int usePayload

payload* pl

int useAppliedForce

triple toolForce

triple toolTorque

endPointRec* endPt

const char* payloadLabel

int payloadConnectorID

int alignPayload

Public Methods

virtual void getStartPoint(triple &t, quaternion &q)

virtual vector computeVel(double dt, quaternion* outputFrame = NULL)

virtual void reset(void)

virtual int atStart(void)

virtual int done(void)

virtual double completion(void)

virtual triple computeCrossTrackError(triple &pos)

virtual triple computeOrientationError(quaternion &q)

Inherited from d2kComponent:

Public Fields

d2kSimulator* sim

configuration* cfg

const char* label

int active

Public Methods

virtual int minCfgs(void) const

virtual int maxCfgs(void) const

virtual const char* getCfgName(int i)

virtual int readParams(paramParser* parser)

virtual int simInit(d2kSimulator* Sim)

virtual int init(ptrList* Cfgs)

virtual int forceCfgResolution(void)

virtual int cleanup(void)

virtual int update(int &violated)

virtual const cfgLabelRecord* getLabelRec(int i) const

Inherited from synObject:

Public Fields

static int staticClassID

int objectID

int verboseLevel

Public Methods

virtual const char* className(void) const

virtual synObject* copy(void) const

virtual int isOfType(int typeNum, int derivedOk)

static int setStaticClassID(void)

virtual int classID(void) const

Documentation

cartesian-space velocities that are fixed in space. The path is represented as a series of waypoints, each of which consists of a world-space position and orientation. The path will generate cartesian-space velocity commands that sequentially move the end effector towards each waypoint. Once the effector is with a certain distance of a waypoint (determined by the tol member), the next waypoint is pursued. Waypoints can either be stopped at or moved through, depending on whether stopAtPoint[i] is 0 or 1.

Cartesian-space PID control is used to compute angular and linear acceleration commands that follow a trapezoidal velocity profile. The PID gains are computed internally from maxVel, maxAcc, maxOmega, and maxOmegaDot; these can be read from a p-file, or can be specified by task parameters. When performing synthesis, it is best to include these four values as task parameters, since they have a significant impact on robot performance.

File variables

• int np required
• double vel = 1;
• double maxAcc = 20;
• double omega = pi/2;
• double maxOmegaDot = pi;
• int useSameTol = 1;
• double tol = 0.002; (only read if useSameTol is 1)
• double vTol = 0.001; (only read if useSameTol is 1)
• double angleTol = pi/20; (only read if useSameTol is 1)
• int readPath = 1;
• char pathFilename[] (required read if readPath is 1)

If readPath is 1, then pathFilename should specify a relative or absolute path (in the filesystem sense) to a path file. The path file contains np waypoint records, each in the following format:

• 0 or 1 indicating whether the point should be stopped at
• 3 floats for the waypoint location
• 4 floats for the waypoint orientation
• if useSameTol is 0, then 3 floats for tol, vTol, and angleTol, respectively.

  Also see genericPath documentation for other variables.

int np

number of points in the path

int currentPt

the most recently-reached point on the path

int targetPt

the point that the end effector is currently headed towards

double targetDist

distance to target point

int useSameTol

use same tolerances for each point?

double* tol

the position tolerance for each waypoint. If useSameTol is 1, then tol points to a single double, which is used as the tolerance for all waypoints. If useSameTol is 0, then tol points to an array of np doubles specifying tolerances for each waypoint.

double* vTol

the velocity tolerance for each waypoint. If a point should be stopped at, then vtol determines how slowly the end effector should be moving to be considered motionless. If useSameTol is 1, then vTol points to a single double, which is used as the tolerance for all waypoints. If useSameTol is 0, then vTol points to an array of np doubles specifying tolerances for each waypoint.

double* angleTol

the angular tolerance for each waypoint. If useSameTol is 1, then tol points to a single double, which is used as the tolerance for all waypoints. If useSameTol is 0, then tol points to an array of np doubles specifying tolerances for each waypoint.

double vel

desired linear velocity

double omega

desired angular velocity

double maxAcc

maximum linear acceleration

double maxOmegaDot

maximum angular acceleration

triple* waypt

an array of waypoint positions

quaternion* orientation

an array of waypont orientations

int* stopAtPoint

an array indicating whether the end effector should stop at each waypoint (ie. decelerate to zero velocity) or move through without decelerating. vTol determines how slowly the effector must be moving to be considered stopped.

virtual int setVariables(const ptrList* taskParams)

sets path-specific variables from a list of task parameters. The variables used by this function are:

• vel
• omega
• maxOmegaDot
• maxAcc

See the member documentation for more information on these variables. It is highly recommended that you included these variables as task parameters when doing synthesis, since they have a significant impact on the robot's ability to accurately follow the path

virtual int getTargetPoint(const triple &pos, const quaternion &q, triple &targetPos, quaternion &targetQ)

returns the target position and orientation given an end effector pose

virtual void getPoint(int i, triple &pos, quaternion &q)

returns the world-space pose of the i'th waypoint

virtual void modifyEndpointPoseAndPath(triple &pos, quaternion &q, triple &tpos, quaternion &tq)

a hook to allow derived classes to modify the pose of the point returned by getPoint

virtual void modifyVelocityCommand(triple &v, triple &omega)

a hook to allow derived classes to modify the velocity command computed by computeVel()

virtual void setNumPoints(int n, int useSameTol)

resizes the arrays for storing path information. NOTE: this does not preserve existing path data.

Direct child classes:

relativePath

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