Minimum jerk relative move

Description

Translate or rotate the robot with a smooth acceleration.

Library Description

The minimum_jerk_trajectory_planner repository contains the implementation of the library.

The following classes are used to generate a trajectory:

• Acceleration contains the parameters of an acceleration vector (x, y, theta)
• Velocity contains the parameters of an velocity vector (x, y, theta)
• Pose contains the parameters of an pose vector (x, y, theta)
• Trajectory compute the acceleration and the velocities (accelerations, velocities) from a timestamps vector and a poses vector
• TrajectoryPlanner:
  • the constructor take total_time which is the duration of the action and dt which is the interval between each intermediate pose, velocity, acceleration
  • the function generate_trajectory compute list_timestamps vector and a list_poses vector from a start pose and a target pose
• Robot:
  • the constructor take a ǹame, the total_time which is the duration of the action, a reference to a TrajectoryPlanner path_finder_controller, the start pose pose_start, the target pose pose_target and the move_type ("r" or "tx" or "ty")
  • the function generate_trajectorycompute the Trajectory odometry with the TrajectoryPlanner path_finder_controller

All parameters of all classes are accessible with getters.

Rotate Action

#goal definition
float32 target_yaw
float32 min_velocity
bool enable_collision_check
float32 yaw_goal_tolerance
bool enable_data_save
---
#result definition
builtin_interfaces/Duration total_elapsed_time
---
float32 angular_distance_traveled

Translate Action

#goal definition
float32 target_x
float32 min_velocity
bool enable_collision_check
float32 xy_goal_tolerance
bool enable_data_save
---
#result definition
builtin_interfaces/Duration total_elapsed_time
---
float32 distance_traveled

Evolution in time

Minimum Jerk Relative Move

• Launch the minimum jerk lifecycle node: ros2 launch minimum_jerk_ros minimum_jerk_launch.py
• Request rotation: ros2 action send_goal /rotate minimum_jerk_msgs/action/Rotate "{target_yaw: 2.7, min_velocity: 1, enable_collision_check: true, yaw_goal_tolerance: 0.1, enable_data_save: false}" --feedback
• Robot should be rotating by 2.7 rad.
• Request translation: ros2 action send_goal /translate minimum_jerk_msgs/action/Translate "{target_x: 2, min_velocity: 0.2, enable_collision_check: true, xy_goal_tolerance: 0.01, enable_data_save: false}" --feedback
• Robot should be translating by 2 m.

Documentation About Minimum Jerk Trajectory

See this documentation online.