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UR5 zero position and ROS zero position different

To Whom It May Concern,

After updating partition sizes on the hard drive used by my Lab's Clearpath Husky equipped with a Universal Robots UR5, ROS continues to communicates accurately with the arm. However, the ROS zero position for the ur5armshoulderpanjoint is 90 degree, pi/4, different on the physical arm. The tool0controller, created by urmoderndriver, shows the accurate position of the end effector. However, the physical links themselves are off. As a result, when I send the UR5 to specified positions, the arm ends up in the wrong position because the ur5armshoulderpanjoint is off 90 degrees. I've looked into the huskyur5moveitconfig, https://github.com/husky/husky/tree/indigo-devel/husky_ur5_moveit_config, and urmoderndriver, https://github.com/ThomasTimm/ur_modern_driver, but haven't found anything that could cause this issue.

The only solution I've thought of yet is physically bolting the arm 90 degrees different from its current position; so that, ROS and the UR5 arm agree on their position. However, this isn't ideal.

Thank you for taking the time to read this post, as well as any help you are able to give. Have a great week. God bless.

Very Respectfully, CMobley7

Asked by CMobley7 on 2016-06-21 12:19:35 UTC

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Answers

To Whom It May Concern,

Adjusting the arm 90 degrees solved the issue.

Very Respectfully, CMobley7

Asked by CMobley7 on 2016-06-30 21:02:57 UTC

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Given your description of the problem (changing setup of the embedded computer of a Husky), and the fact that it's actually a commercial product supported by a company, perhaps it'd be a good idea to take this up with Clearpath support? Seems strange that a hdd migration would cause this.

Asked by gvdhoorn on 2016-07-01 02:00:54 UTC

I should have this clarified above. The UR5 worked correctly after resizing the partition. However, the husky_base no longer had comm with ROS. Clearpath support was able to solve this issue; however, after which the UR5 no longer had comm with ROS. The issue above surfaced after comm was restored.

Asked by CMobley7 on 2016-07-01 11:14:38 UTC

can I ask you how do send specific positions for ur5 joints. ??

Asked by Abdu on 2018-04-23 13:19:56 UTC