Ask Your Question
0

"WARNING: no messages received and simulated time is active. Is /clock being published?" - Force Torque

asked 2018-03-20 23:18:05 -0600

lr101095 gravatar image

updated 2018-03-21 17:40:24 -0600

Running ubuntu 16.04, ROS kinetic, gazebo 7.

Trying to implement a force torque sensor model onto the end-effector of a sawyer robot. Model was successfully implemented, but plugin doesn't publish any data. I get the warning from the question title. Yes, /clock is being published because calling "rostopic echo /clock" will show the simulation clock.

warning occurs when i call "rostopic echo /right_hand_ft_sensor/ft_sensor_topic

I've found solutions where it suggests to call the following: "rosparam set use_sim_time false" and that hasn't fixed anything.

I've also seen solutions where it says to set the update_rate of the sensor to 0 in the robot.urdf. I can't try this solution because my sawyer.urdf does not contain the relevant section in the code where i would can set it the update rate to 0. the sensor package is based on xacro and i just include in the launch file of the sawyer robot.

any suggestions or advice would be much appreciated.

edit retag flag offensive close merge delete

Comments

What command are you running that causes the warning message to be published?

imcmahon gravatar imageimcmahon ( 2018-03-21 09:10:31 -0600 )edit

@imcmahon please see edited post

lr101095 gravatar imagelr101095 ( 2018-03-21 17:39:41 -0600 )edit

1 Answer

Sort by ยป oldest newest most voted
0

answered 2018-03-21 09:20:39 -0600

imcmahon gravatar image

updated 2018-03-21 09:33:50 -0600

(Hopefully) you shouldn't need to implement your own force-torque sensor for Sawyer in Gazebo. The sawyer_gazebo package actually simulates the torque values being experienced by each joint in the arm directly. You can see each of these torques on the topic /robot/joint_states. A force-torque sensor is usually used to measure the force experienced at the end effector of the robot. Part of the simulation is a handy topic that reports all of these joint torques are transformed into the endpoint frame on the /robot/limb/right/endpoint_state topic using the intera_core_msgs/EndpointState message.

The following is the RViz rendering of the effort portion of the /robot/joint_states topic: Sawyer RViz Torques in Gazebo

edit flag offensive delete link more

Comments

i forgot to mention that i'm implementing the ft sensor on the end-effector of sawyer. made the correction in my post.

lr101095 gravatar imagelr101095 ( 2018-03-21 17:41:30 -0600 )edit

Ah, I see. I would recommend looking at the endpoint_state topic I mentioned above. It should give you the same data that a FT sensor would give in the endpoint frame.

imcmahon gravatar imageimcmahon ( 2018-03-21 18:06:05 -0600 )edit

Your Answer

Please start posting anonymously - your entry will be published after you log in or create a new account.

Add Answer

Question Tools

2 followers

Stats

Asked: 2018-03-20 23:18:05 -0600

Seen: 653 times

Last updated: Mar 21 '18