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MuSHR is an open-source robotics platform for learning and researching AI with autonomous vehicles.


Problem with Initial Tutorial

December 21, 2020 at 4:28am

Problem with Initial Tutorial

December 21, 2020 at 4:28am
Hello, Everthing went well with the initial tutorial until playing with the keyboard WASD to make the car move in the simulation. It works when the map is sandbox.yaml but if I change the map to any other real-floor0 or real-floor4_corridor it does not work. In the real-floor4_corridor, the car is inside the wall not in the corridor and I do not know how to place the car in the corridor.
Thank you for any help.

December 21, 2020 at 12:49pm
Hi precioso! If you click 2D Pose Estimate then click and drag in a free region of the environment, the car should appear where you clicked.

December 24, 2020 at 1:43am
Thank you so much!
Unfortunately, I was a bit too optimistic with my previous post. The tutorial code is very unstable (on my machine at least). Sometimes it works, sometimes it doesn't. I always get the following error message:
[FATAL] [1608773386.317267100]: Failed to load nodelet '/car/mux/ackermann_cmd_muxof typeackermann_cmd_mux/AckermannCmdMuxNodeletto managernodelet_manager'
Then I get the following repeated error:
[ WARN] [1608773386.692329100]: Shutdown request received. [ WARN] [1608773386.733229000]: Reason given for shutdown: [new node registered with same name] [car/mux/ackermann_cmd_mux-7] process has died [pid 4196, exit code 255, cmd /opt/ros/melodic/lib/nodelet/nodelet load ackermann_cmd_mux/AckermannCmdMuxNodelet nodelet_manager /car/initialpose:=/initialpose name:=ackermann_cmd_mux log:=/home/precioso/.ros/log/3ea91156-432b-11eb-ab5e-00155d8cbdfd/car-mux-ackermann_cmd_mux-7.log]. log file: /home/precioso/.ros/log/3ea91156-432b-11eb-ab5e-00155d8cbdfd/car-mux-ackermann_cmd_mux-7*.log [car/mux/ackermann_cmd_mux-7] restarting process
This is not directly related with the initial tutorial working or not, since I always get these errors, but then sometimes WASD is moving the car, sometimes nothing moves. I use Mushr install in Windows 10, inside WSL2 with ROS Melodic and VcXsrv.
Thank you again for your help, changing the car location works now with your help on any map like on real-floor4_corridor.

December 24, 2020 at 6:07pm
Yeah it seems somehow two ackermann_cmd_mux are being possibly being started calling this error. As a quick sanity check: are you using WASD while clicked on the gray window? And the car is in free space?
Thank you very much Matt for answering while you are probably preparing Xmas eve. The answers to your sanity check are both yes: using WASD while being in the gray window and while the car is in free space. Something I identified is that it seems related to the order for the processes to be launched: when I launch the ros command, then when I launch the rviz command, and the time I Iet between these two commands and also with using WASD keys. I suspect it could be related to WSL2 processing which is not as direct as launching everything in a Ubuntu system. Thank you again very much for spending time helping me. I will investigate all this next year.
Best wishes

January 4, 2021 at 7:14pm
hmm yeah this is an unusual issue that could be related to you windows install. How exactly did you install the stack?
In regards to timing, does it work if you wait 10 seconds between launching the sim and launching rviz? it seems odd that it would be related to that because rviz just visualizes everything. Something you could try is launch the sim in the sandbox. Then run rostopic echo /car/car_pose and try WASD and whether the position numbers are changing. This separates whether it is a problem with rviz (unlikely).