Setting workspace bounds

[adhitir]

What is the best way to set hard workspace limits on the motoman hc10dt?
The inverse kinematics solutions sometimes lead to configurations that take move the joints of the robot and make it collide with the floor. Obviously, I wish to avoid this as its really hard to move the robot out of a collided pose. How can I set hard workspace bounds for the robot, not for the end-effector in task space but to avoid joint collisions with the floor.

[EricMarcil]

You can setup spatial limits with the Functional Safety Unit (FSU).
Please refer to the related manuals:
https://www.motoman.com/getmedia/53EE5B5C-74C0-44BC-B8C9-96A751B7ED41/178949-1CD.pdf.aspx?ext=.pdf

[adhitir]

Is there a similar manual but for the smart pendant?

[EricMarcil]

It's in the Smart Pendant manual, section 11.4 Functional Safety Functions
https://www.motoman.com/getmedia/B0793234-D85A-478B-B17C-6456372EA2DB/184775-1cd.pdf.aspx?ext=.pdf

[gavanderhoorn]

The inverse kinematics solutions sometimes lead to configurations that take move the joints of the robot and make it collide with the floor.

are you using a motion planner -- like MoveIt or Tesseract?

if you are, I would expect the collision avoidance to prune those solutions as they would be invalid.

Unless your environment model doesn't include all obstacles of course. A robot in an empty space would never be in collision.

If you are not using a motion planner (with environmental awareness), you would be responsible for making sure your trajectories don't collide.

The FSU would be a good thing to configure, but note that it would be completely invisible to ROS. It will not affect motoman_driver directly, nor will it inform anything on the ROS side about any additional limitations you've configured.

[adhitir]

I'm not using a motion planner. I'm using trac_ik and I'm working with real hardware so I have the floor to contend with. I'm not worried about the tool, I'm worried about the robot joints. During one of the trajectories I set, the robot moved in a weird way and the elbow collided with the floor.

[gavanderhoorn]

I'm using trac_ik [..]

if you're just using plain IK solutions than that could explain why you're running into the issue you describe.

There is no environment model used anywhere by trac_ik, so the best you could do would be limiting the allowable joint ranges. But that's not necessarily a good approach, as depending on the joint(s), it will severely limit the search space.

The only thing I could suggest would be make sure you've set the solve_type parameter of trac_ik to Distance.

There is nothing in the driver which could help you with this I'm afraid.

[EricMarcil]

It's in the Smart Pendant manual, section 11.4 Functional Safety Functions
https://www.motoman.com/getmedia/B0793234-D85A-478B-B17C-6456372EA2DB/184775-1cd.pdf.aspx?ext=.pdf

[adhitir]

Thank you very much. Would you also happen to know what the default password to enter the safety mode is?

[EricMarcil]

The default password is 5555555555555555 (16 of them) but most system ship with a unique preset password.
It should have been included with robot documentation in a large sealed envelop.
If you cannot find it, you will have to contact the technical support department. For North America that would be: [email protected]

This is no longer ROS related questions, so I will be closing this discussion. Tech Support should be able to help you with any robot setting and operation related questions.