Banachowicz¶

Proposed by Konrad Banachowicz

Part of http://wiki.ros.org/trajectory_msgs/Reviews/Cartesian%20Trajectories_API_Review_2013_06_05

Feature list¶

Multiple possible effector names

Multiple trajectories in one goal (One for each effector?)

Trajectory points consist of pose and twist

Contains impedance for each effector with * Center of compliance * stiffness * damping

Contains path and goal tolerances in * absolute position distance * absolute rotation angular error * absolute linear velocity * absolute angular velocity

Contains posture information to handle redundancies (for each effector???)

Contains a nullspace impedance

Features required from hardware / driver¶

Control interface

Impedance control

Message definition¶

[CartesianTrajectoryGoal]
Header header  # A stamp of 0 means "execute now"
string[] effector_names
CartesianTrajectory[] trajectory
  Pose tool  # The frame (offset ?) which is being controlled or it can be treated as separate effector ?
  CartesianTrajectoryPoint[] points
    duration time_from_start
    Pose pose
    Twist twist
CartesianImpedance[] impedance
    Pose center_of_compliance # or it can be treated as separate effector ?
    TBD stiffness % cartesian stiffness
    TBD damping % damping ratio
CartesianTolerance[] path_tolerance  # Tolerance for aborting the path
  float64 position
  float64 orientation  # Permitted angular error
  float64 velocity
  float64 angular_velocity
CartesianTolerance[] goal_tolerance  # Tolerance for when reaching the goal is considered successful
string[] joint_names
JointTrajectoryPoint[] posture  # For determining the redundancy
JointImpedance[] nullspace_impedance
  float64[] stiffness
  float64[] damping