Problems with model, simulation behaves like there is moon gravity - Solved [closed]

asked 2017-09-19 03:48:12 -0500

wentz gravatar image

updated 2017-10-02 06:17:37 -0500

Hi Guys,

i have pretty bad problems with my model of the KUKA youbot. I used this model with Gazebo-2 and ROS Indigo and all was pretty fine. Since i have went to Gazebo 7 - ROS Kinetic the model behaves strange like its falling in super slow motion and when i give velocity commands its doing a wheely.image description

I recently tried: - changing the inertias of all links - converted the model to a sdf file and spawned the sdf and nothing changed the result.

I tried also to use the official gazebo model of KUKA youbot, but every time I spawn it, the gazebo window hangs and i have to force a quit.

The unmodified model i use can be found here: github/luh_youbot_os. The inertias of the model might look much to big but the behavior is the same as with my modified model.

If someone has any idea, i will be grateful for help.

Edit: I debugged my nodes to control the robot in the simulation. These are basically the plugins of gazebo_ros_pksg that are slightly modified. The problem was the joint controller that uses a SetPosition() function in the UpdateChild() function of the controller. If anyone has a similar problem try the changes shown in the screenshots below:

This is how it looks before

image description

Here are the changes i made

image description

edit retag flag offensive reopen merge delete

Closed for the following reason question is off-topic or not relevant by wentz
close date 2017-09-20 04:53:51.161080


Have you tried inserting the robot without connecting to ROS at all? Do you still see the strange behavior?

chapulina gravatar imagechapulina ( 2017-09-19 11:04:30 -0500 )edit

So i tried it and it shows up that there is no problem with the model when i uncomment all ROS plugins in the sdf. This also means there is a problem with the joint controller i use... which is even worst. But well now i know where to search. Thanks!

wentz gravatar imagewentz ( 2017-09-19 14:17:47 -0500 )edit