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moveit / moveit_task_constructor

A hierarchical multi-stage manipulation planner
https://moveit.github.io/moveit_task_constructor
BSD 3-Clause "New" or "Revised" License
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travel (trajectory) length and time of end-effector joint #599

Open h3ngy1ng opened 1 month ago

h3ngy1ng commented 1 month ago

[rookie] ive a robot arm of 6 joints and would like to know:

  1. how does mtc and rviz know joint1 corresponds to the base joint, etc.
  2. i have the below code snippet calc the total trajectory length and time but i believe it computes both linear and rotary movement of all 6 joints. (x, y, z) from home position to an arbitrary (0, 0.5, 1.5) metres: Screenshot from 2024-07-18 10-02-32 Screenshot from 2024-07-18 10-03-57

how do i verify mtc and rviz are reading the last joint (joint 6) as end-effector joint and get the travel (trajectory) length, time of specified joint.

rhaschke commented 1 month ago
  • how does mtc and rviz know joint1 corresponds to the base joint, etc.

From the URDF, which defines the kinematics as a tree. The root of the tree is the base link / joint.

  • i have the below code snippet calc the total trajectory length and time but i believe it computes both linear and rotary movement of all 6 joints.

Indeed this only computes path length in joint space. Have a look at the existing cost functions instead: