UR10 Gazebo Launching Problem

[mjpatell]

Hello all,
I am using UR10 arm. While lunching gazebo model of UR10 arm in the kinetic, it is falling down on the ground. I think but not sure this is the problem of the gravity. I tried to tune this parameter but not successed yet. If any one facing same problem and solve it than please let me know.

My setup:

• Ubuntu 16.04
• ROS Kinetic
• UR10 arm

[shloakmehta]

gazebo 7 or 9?

[mjpatell]

gazebo 7

[shloakmehta]

So I get these errors too which - according to the last two warnings - gravity acts weird, and to solve it, we either have to set gazebo_pid parameters, switch to the VelocityJointInterface or EffortJointInterface, or upgrade to Gazebo 9.

I may be wrong and am about to try myself right now with the UR10 but according to ros-simulation/gazebo_ros_pkgs#612 it should be the solution.

Let me know how you get on...

[ERROR] [1542388350.763274103, 0.342000000]: No pgain specified for pid.  Namespace: /gazebo_ros_control/pid_gains/shoulder_pan_joint
[ERROR] [1542388350.765508662, 0.342000000]: No p gain specified for pid.  Namespace: /gazebo_ros_control/pid_gains/shoulder_lift_joint
[ERROR] [1542388350.767169872, 0.342000000]: No p gain specified for pid.  Namespace: /gazebo_ros_control/pid_gains/elbow_joint
[ERROR] [1542388350.768819330, 0.342000000]: No p gain specified for pid.  Namespace: /gazebo_ros_control/pid_gains/wrist_1_joint
[ERROR] [1542388350.770428920, 0.342000000]: No p gain specified for pid.  Namespace: /gazebo_ros_control/pid_gains/wrist_2_joint
[ERROR] [1542388350.772307131, 0.342000000]: No p gain specified for pid.  Namespace: /gazebo_ros_control/pid_gains/wrist_3_joint
[ INFO] [1542388350.785158214, 0.342000000]: Loaded gazebo_ros_control.
[ WARN] [1542388350.786564225, 0.343000000]: The default_robot_hw_sim plugin is using the Joint::SetPosition method without preserving the link velocity.
[ WARN] [1542388350.786622491, 0.343000000]: As a result, gravity will not be simulated correctly for your model.
[ WARN] [1542388350.786664522, 0.343000000]: Please set gazebo_pid parameters, switch to the VelocityJointInterface or EffortJointInterface, or upgrade to Gazebo 9.

[ipa-nhg]

@ipa-mjp could you please give some details about how did you started the simulation?

This command roslaunch ur_gazebo ur10.launch ?? For kinetic and gazebo 7 this should work. Usually the error you have (as @shloakmehta pointed) is a problem with the controllers, the log should point to the concrete problem. Generally, an update of the controllers is strongly recommended for this cases. Also check that all the required packages are installed:

rosdep install --from-path src/universal_robot/ur_gazebo

@shloakmehta I have never had this issue, unfortunately I can't reproduce it. did you solve the problem? Are you mounting somewhere the arm or is it a "arm-solo setup"?

[waiyc]

@ipa-mjp Did you run this command line

sudo apt-get install ros-kinetic-universal-robot

[padhupradheep]

Hey,

ROS Distro: Kinetic
Gazebo Version: 7.0
I'm also facing the same issue with the position controller. If I use effort controllers or velocity controller as per the ros-simulation/gazebo_ros_pkgs#612 , I'm not sure on what PID values that needs to be set for the gains of both the arm controller and the gazebo ros controller. As I tried to follow this discussion in https://answers.ros.org/question/284241/mobile-arm-simulation-behaves-strangely-when-adding-ros_control-plugin-for-arm/ , still the robot wobbles.

Any help will be appreciated!

[ipa-nhg]

Unfortunately set the pid gains just break the arm and can't be controlled anymore. Our current version is working, although Gazebo shows the errors. Then I just can suggest to ignore the errors.
I open a PR with my experiments, keeping the pid configuration commented out for now:
#443