Robotics StackExchange | Archived questions

turtlebot_arm, no motion plan found error

image description I m trying to use turtlebot_arm package for ROS hydro. it runs perfect with setting start and end state in rviz workspace but when i run the pick and place code it gives me this error...

"[ WARN] [1433588765.336846927]: Fail: ABORTED: No motion plan found. No execution attempted."

i have searching over the internet but couldnt find any solution to this issue i even tried on indigo but same problem occurs..

Asked by Nouman Tahir on 2015-06-08 13:03:22 UTC

Comments

Answers

Hi, probably you hit over this issue. To verify this, please check the moveit's log and look for messages saying something ¨Orientation constraint violated ..."

If this is your problem, you need either to

a) modify moveit code as I did b) try this workaround

good luck!

btw, I improved turtlebot_arm greatly on indigo.... you cannot use it instead of hydro?

Asked by jorge on 2015-06-08 15:40:28 UTC

Comments

i have tried in indigo as well but facing same error. the issues you linked plans the path in some way but my arm does not plan any path at all, all it does with pick and place code is goes from home to rest pose

Asked by Nouman Tahir on 2015-06-09 01:19:20 UTC

There are not turtlebot_arm hydro branch, so I understand you are running indigo devel code on hydro, right? Are you trying the running moveit demo? In emulation or with real robot (should not make any difference)

Asked by jorge on 2015-06-10 14:38:30 UTC

Running "roslaunch turtlebot_arm_moveit_config demo.launch" and then "rosrun turtlebot_arm_moveit_demos pick_and_place.py" works for me, so I need more details to reproduce the problem

Asked by jorge on 2015-06-10 15:15:30 UTC

Yes, I m running it on hydro but even in indigo it fails with same error meassage and I m trying in simulation only I couldn't find any source to buy it up till now, plz let me know if u know any source.

Asked by Nouman Tahir on 2015-06-11 04:01:35 UTC

When you start "roslaunch turtlebot_arm_moveit_config demo.launch" without arguments, it starts a "fake" arbotix controller that just mover the arm model on RViz, so you can run pick and place demo without a real robot. Of course this is not a simulation, but is an easy start.

Asked by jorge on 2015-06-11 05:29:52 UTC

That said, I can simulate the arm on Gazebo. LAunch and config files are here. But I would rather try to fix the planning problem just starting moveit with a "fake" arm, as explained in my previous comment

Asked by jorge on 2015-06-11 05:32:33 UTC

in my case, i dont have real arm at all, i have clone turtlebot arm from github and built is using catkin_make after resolving arbotix and dependencies and using the hydro version of moveit. even running the pick and place with demo.launch doesnot work. p.s. moveit pr2 tutorial codes runs fine

Asked by Nouman Tahir on 2015-07-01 04:39:38 UTC

please do refer to screenshot I posted

Asked by Nouman Tahir on 2015-07-01 04:57:47 UTC

Hi again, sorry, I'm quite puzzled by your problem. Watching at the screenshot, seems like you have a (simulated?) kinect. Just a guess: could be that the kinect "sees" an obstacle blocking the pick path?

Asked by jorge on 2015-07-01 18:53:12 UTC

Another thing to try: can you use the moveit RViz interactive marker to move the arm somewhere close to the pick target? would be interesting to verify if is just a pick problem or a general planning problem

Asked by jorge on 2015-07-01 18:54:01 UTC

moving arm using interactive marker works perfect, i cleanly plan and execute paths on rviz simulaiton

Asked by Nouman Tahir on 2015-07-01 20:06:37 UTC

p.s. i have no kinect in simulation though i have one for robot but its not connected. after attempting for pick operation, the arm directly goes to the rest/folded position

Asked by Nouman Tahir on 2015-07-01 20:09:21 UTC

did you try to set the interactive market over the object to pick? if it works, there must be something wrong with the pick part. Also you said that PR2 demo works... it is on C++, so,,,, maybe your problem has something to do with the Python wrapper. Did you try to rewrite the demo as C++?

Asked by jorge on 2015-07-02 05:59:54 UTC

hmm okay i should give it a try, anyway do you think this could have caused because of 4-dof arm instead of 6-dof

Asked by Nouman Tahir on 2015-07-02 18:26:51 UTC

normally not; in the movit configuration there´s an extra 5th "fake" joint so moveit can generate paths for a 4-dof arm. But this small number of dofs imposes that, for pick, the grasping pose cannot be arbitrary. But unless you changed these poses in the demo, it should work

Asked by jorge on 2015-07-06 06:30:57 UTC

sorry i couldnt update post in while, can you tell me where i can have instructions on building a real arm....files for 3d printing and other stuff so i may be able to test it for real

Asked by Nouman Tahir on 2015-09-17 10:10:11 UTC

Sure! http://wiki.ros.org/turtlebot_arm/Tutorials/indigo/AssemblingTheTurtlebotArm Btw, did the simulation finally work?

Asked by jorge on 2015-10-08 11:21:37 UTC

Not but I was close, one of the issue is with python library using c++ helps, but it was too late, my juniors are now working on this project and I am helping them to get the best out in limited time.

Asked by Nouman Tahir on 2015-10-11 09:48:48 UTC