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I follow tutorials in *http://docs.ros.org/kinetic/api/moveit_tutorials/html/doc/pr2_tutorials/planning/src/doc/move_group_interface_tutorial.html*,and when i plan a Cartesian Paths for UR3, i write the following codes for UR3:

std::vector<geometry_msgs::Pose> waypoints;

  geometry_msgs::Pose target_pose2 = target_pose1;

  target_pose2.position.z += 0.1;
  waypoints.push_back(target_pose2);  // up 
   target_pose2.position.y -= 0.1;
  waypoints.push_back(target_pose2);  // left
  target_pose2.position.z -= 0.1;
  target_pose2.position.y += 0.1;
  target_pose2.position.x -= 0.1;
 moveit_msgs::RobotTrajectory trajectory;
  const double jump_threshold = 0.0;
  const double eef_step = 0.005;
  double fraction = move_group.computeCartesianPath(waypoints, eef_step, jump_threshold, trajectory);
  ROS_INFO_NAMED("tutorial", "Visualizing plan 4 (cartesian path) (%.2f%% acheived)", fraction * 100.0);

ROS_INFO_STREAM("cartesian path .....");
my_plan.trajectory_= trajectory;

The problem is that the fuction double fraction = move_group.computeCartesianPath(waypoints, eef_step, jump_threshold, trajectory); seems work not well .In the terminal i got the following information:

 INFO] [1489330212.136327474]: Visualizing plan 4 (cartesian path) (0.00% acheived)
[ INFO] [1489330227.136626416]: cartesian path .....
[ WARN] [1489330227.461583608]: Skipping path because 1 points passed in.

Some problem occur when running the function for 0.00% has achieved as terminal implied. So it didn't plan out the cartesian path. soi can't see the path in rviz.

Originally posted by kaijianliu on ROS Answers with karma: 36 on 2017-03-12

Post score: 0

Original comments

Comment by jrgnicho on 2017-03-14:
I see that you are making tool motion increments of 0.1 m for each point which may cause some of the points to have unreachable orientation, especially in the case of an arm with a small work envelope like the UR3.

Comment by jrgnicho on 2017-03-14:
See the method description here

Comment by tengfei on 2017-12-21:
hello,I also have the same question.so you mean that the first point of the cartesian path should be the gurrent pose of the robot right? By the way how can I know whether the point I want to put in the waypoints is reachable before I fail to compute the path?


1 Answer 1


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I have worked out the problem. It was due to the reason that i should execute to the start point of the waypoints before i start compute cartesian. And also, I should set a longger time for compute cartesian path to ensure 100% acheved. Anyway, thanks.

Originally posted by kaijianliu with karma: 36 on 2017-03-14

This answer was ACCEPTED on the original site

Post score: 2


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