Trajectory Planner APIs

The trajectory planner APIs are implemented by the following classes. You can find the corresponding header files in the c++/include/drivers/traj directory to access the complete set of APIs.

Header File	Class Name	Description
trajectory.h	Trajectory	Trajectory class that provides interfaces for managing trajectories and trajectory points.
trajectory_planner.h	TrajectoryPlanner	Defines the generic interface for trajectory planners, supporting different planning algorithms.
	CollisionChecker	Interface for collision-avoidance constraints.
poly5_planner.h	Poly5Planner	Trajectory planner based on fifth-order polynomials, providing smooth acceleration and deceleration. Inherits from TrajectoryPlanner class.

Trajectory

Add a Trajectory Point

• Method:

  void addPoint(const TrajectoryPoint& point)

• Parameter:

  Parameter	Type	Description
  point	Input	Trajectory point. For details, please refer to TrajectoryPoint.

• Return Value:

  None (void).

Get a Trajectory Point

• Method:

  const TrajectoryPoint& getPoint(size_t index) const

• Parameter:

  Parameter	Type	Description
  index	Input	Index of the trajectory point.

• Return Value:

  Trajectory point. For details, please refer to TrajectoryPoint.

Get a Trajectory Point at a Specified Time

• Method:

  TrajectoryPoint getPointAtTime(AbcType time, bool interpolate = true) const

• Parameters:

  Parameter	Type	Description
  time	Input	Timestamp. For details, please refer to AbcType.
  interpolate	Input (optional)	Whether to perform interpolation.

• Return Value:

  Trajectory point. For details, please refer to TrajectoryPoint.

Get the Number of Trajectory Points

• Method:

  size_t size() const

• Return Value:

  Number of trajectory points.

Get Total Trajectory Duration

• Method:

  AbcType getDuration() const

• Return Value:

  Total trajectory duration. For details, please refer to AbcType.

Get Joint Count

• Method:

  size_t getJointCount() const

• Return Value:

  Number of joints.

Check if Trajectory is Empty

• Method:

  bool empty() const

• Return Value:

  true if empty, false otherwise.

Clear Trajectory

• Method:

  void clear()

• Return Value:

  None (void).

Set Trajectory Name

• Method:

  void setName(const std::string& name)

• Parameter:

  Parameter	Type	Description
  name	Input	Trajectory name.

• Return Value:

  None (void).

Get Trajectory Name

• Method:

  const std::string& getName() const

• Return Value:

  The trajectory name.

Save Trajectory to a File

• Method:

  bool saveToFile(const std::string& filename) const

• Parameter:

  Parameter	Type	Description
  filename	Input	File path and name.

• Return Value:

  true if saved successfully, false otherwise.

Load Trajectory from a File

• Method:

  bool loadFromFile(const std::string& filename)

• Parameter:

  Parameter	Type	Description
  filename	Input	File path and name.

• Return Value:

  true if loaded successfully, false otherwise.

Get All Trajectory Points

• Method:

  const std::vector<TrajectoryPoint>& getPoints() const

• Return Value:

  The container of all trajectory points. For details, please refer to TrajectoryPoint.

Trim Trajectory

• Method:

  Trajectory trim(AbcType start_time, AbcType end_time) const

• Parameters:

  Parameter	Type	Description
  start_time	Input	Start time. For details, please refer to AbcType.
  end_time	Input	End time. For details, please refer to AbcType.

• Return Value:

  The trimmed trajectory.

Append Trajectory

• Method:

  Trajectory append(const Trajectory& other, AbcType blend_time = 0.0) const

• Parameters:

  Parameter	Type	Description
  other	Input	Trajectory to be appended.
  blend_time	Input (optional)	Blend time.

• Return Value:

  The appended trajectory.

Trajectory Planner

Initialize Trajectory Planner

The trajectory planner can be initialized in two ways, as described below.

1. Initialize using start and end positions

   • Method:

     bool init(
         const std::vector<AbcType>& start_positions,
         const std::vector<AbcType>& end_positions,
         AbcType duration = 0,
         int velocity_scale = 100)

   • Parameters:

     Parameter	Type	Description
     start_positions	Input	Start positions.
     end_positions	Input	End positions.
     duration	Input (optional)	Planning duration. A value of 0 indicates that the duration is computed automatically.
     velocity_scale	Input (optional)	Velocity scaling factor. Valid range: 0–100.

   • Return Value:

     true if initialization succeeds, false otherwise.

2. Initialize using start/end positions, velocities, and accelerations

   • Method:

     bool initWithVelAcc(
         const std::vector<AbcType>& start_positions,
         const std::vector<AbcType>& start_velocities,
         const std::vector<AbcType>& start_accelerations,
         const std::vector<AbcType>& end_positions,
         const std::vector<AbcType>& end_velocities,
         const std::vector<AbcType>& end_accelerations,
         AbcType duration = 0,
         int velocity_scale = 100)

   • Parameters:

     Parameter	Type	Description
     start_positions	Input	Start positions.
     start_velocities	Input	Start velocities.
     start_accelerations	Input	Start accelerations.
     end_positions	Input	End positions.
     end_velocities	Input	End velocities.
     end_accelerations	Input	End accelerations.
     duration	Input (optional)	Planning duration. A value of 0 indicates that the duration is computed automatically.
     velocity_scale	Input (optional)	Velocity scaling factor. Valid range: 0–100.

   • Return Value:

     true if initialization succeeds, false otherwise.

Compute a Trajectory Point at a Specified Time

• Method:

  bool computeTrajectoryPoint(AbcType time, TrajectoryPoint& point)

• Parameters:

  Parameter	Type	Description
  time	Input	Time relative to the start time. For details, please refer to AbcType.
  point	Output	Trajectory point corresponding to the specified time. For details, please refer to TrajectoryPoint.

• Return Value:

  true if computation succeeds, false otherwise.

Generate Trajectory

• Method:

  Trajectory generateTrajectory(int sample_rate = 100)

• Parameter:

  Parameter	Type	Description
  sample_rate	Input (optional)	Sampling frequency, in Hz.

• Return Value:

  The generated trajectory.

Evaluate Trajectory

• Method:

  TrajectoryEvaluation evaluateTrajectory(const Trajectory& trajectory)

• Parameter:

  Parameter	Type	Description
  trajectory	Input	The trajectory to be evaluated.

• Return Value:

  Evaluation results. For details, please refer to TrajectoryEvaluation.

Set Collision Checker

• Method:

  void setCollisionChecker(std::shared_ptr<CollisionChecker> checker)

• Parameter:

  Parameter	Type	Description
  checker	Input	Collision checker. A shared pointer to a CollisionChecker object.

• Return Value:

  None (void).

Get Total Planned Duration

• Method:

  AbcType getTotalDuration() const

• Return Value:

  Total planned duration.

Register Trajectory Status Callback Function

• Method:

  void setStatusCallback(TrajectoryStatusCallback callback)

• Parameter:

  Parameter	Type	Description
  callback	Input	TrajectoryStatusCallback is a function pointer type. For details, please refer to TrajectoryStatusCallback. The callback function is called whenever a trajectory status update is received.

• Return Value:

  None (void).

Set Maximum Velocity and Acceleration Constraints

• Method:

  void setConstraints(
      const std::vector<AbcType>& max_velocities,
      const std::vector<AbcType>& max_accelerations)

• Parameters:

  Parameter	Type	Description
  max_velocities	Input	Maximum velocities.
  max_accelerations	Input	Maximum accelerations.

• Return Value:

  None (void).

Check a Trajectory Point for Collision

• Method:

  bool checkCollision(const TrajectoryPoint& point)

• Parameter:

  Parameter	Type	Description
  point	Input	Trajectory point. For details, please refer to TrajectoryPoint.

• Return Value:

  true if a collision is detected, false otherwise.

Get Minimum Distance

• Method:

  double getMinDistance(const TrajectoryPoint& point)

• Parameter:

  Parameter	Type	Description
  point	Input	Trajectory point. For details, please refer to TrajectoryPoint.

• Return Value:

  Minimum distance.

Poly5 (Fifth-Order Polynomial) Trajectory Planner

The Poly5Planner class inherits from the TrajectoryPlanner class. The initWithVelAcc() method is newly added, while the other methods are overrides of those in the base TrajectoryPlanner class.

Initialize Trajectory Planner

• Method:

  bool initWithVelAcc(
      const std::vector<AbcType>& start_positions,
      const std::vector<AbcType>& start_velocities,
      const std::vector<AbcType>& start_accelerations,
      const std::vector<AbcType>& end_positions,
      const std::vector<AbcType>& end_velocities,
      const std::vector<AbcType>& end_accelerations,
      AbcType duration = 0,
      int velocity_scale = 100)

• Parameters:

  Parameter	Type	Description
  start_positions	Input	Start positions.
  start_velocities	Input	Start velocities.
  start_accelerations	Input	Start accelerations.
  end_positions	Input	End positions.
  end_velocities	Input	End velocities.
  end_accelerations	Input	End accelerations.
  duration	Input (optional)	Planning duration. A value of 0 indicates that the duration is computed automatically.
  velocity_scale	Input (optional)	Velocity scaling factor. Valid range: 0–100.

• Return Value:

  true if initialization succeeds, false otherwise.

Compute a Trajectory Point at a Specified Time

• Method:

  bool computeTrajectoryPoint(AbcType time, TrajectoryPoint& point)

• Parameters:

  Parameter	Type	Description
  time	Input	Time relative to the start. For details, please refer to AbcType.
  point	Output	Trajectory point corresponding to the specified time. For details, please refer to TrajectoryPoint.

• Return Value:

  true if computation succeeds, false otherwise.

Get Total Planned Duration

• Method:

  AbcType getTotalDuration() const

• Return Value:

  Total planned duration.

Set Maximum Velocity and Acceleration Constraints

• Method:

  void setConstraints(
      const std::vector<AbcType>& max_velocities,
      const std::vector<AbcType>& max_accelerations)

• Parameters:

  Parameter	Type	Description
  max_velocities	Input	Maximum velocities.
  max_accelerations	Input	Maximum accelerations.

• Return Value:

  None (void).