Set joint positions in JointController disabled

[osrf-migration]

Original report (archived issue) by Nate Koenig (Bitbucket: Nathan Koenig).

---

Setting a joint angle in JointController is disabled because updating the collision elements is not working.

Please vote for this issue if you want to see this fixed.

[osrf-migration]

Original comment by Steve Peters (Bitbucket: Steven Peters, GitHub: scpeters).

---

I don't fully understand the description of this bug. Is it related to this code in JointController.cc?

[osrf-migration]

Original comment by John Hsu (Bitbucket: hsu, GitHub: hsu).

---

little more background please, e..g why was it disabled? when was it disabled?

[osrf-migration]

Original comment by Nate Koenig (Bitbucket: Nathan Koenig).

---

It has been disabled for a very long time. The code that would set the joint to a specific position in the update loop was already commented before pull request #1048. Looking at the blame, the comments occurred back in Oct of 2012.

There are no test for this code, and the comments indicate that it's broken. The result is to disable to code and put in a warning message.

If you think the code in question is valuable, please write tests and put it back in.

[osrf-migration]

Original comment by John Hsu (Bitbucket: hsu, GitHub: hsu).

---

@nkoenig Thanks for digging that up! I say we wait for votes or comments.

[osrf-migration]

Original comment by John Hsu (Bitbucket: hsu, GitHub: hsu).

---

needed for atlas animation tutorial

[osrf-migration]

Original comment by John Hsu (Bitbucket: hsu, GitHub: hsu).

---

needed to fix #1072

[osrf-migration]

Original comment by Andreas Bihlmaier (Bitbucket: andreasBihlmaier).

---

This is pretty bad.
I just updated to gazebo 3.0 and found that none of our many use cases, in which we run gazebo with physics disabled and use Joint::SetAngle() through model plugins, are working anymore.

Please increase the priority of fixing this bug.

For now I have to revert to gazebo 2.X.

[osrf-migration]

Original comment by John Hsu (Bitbucket: hsu, GitHub: hsu).

---

• changed priority from "minor" to "blocker"

[osrf-migration]

Original comment by John Hsu (Bitbucket: hsu, GitHub: hsu).

---

working on a fix. Need to recover SetJointPosition et. al.

[osrf-migration]

Original comment by Andreas Bihlmaier (Bitbucket: andreasBihlmaier).

---

Very much appreciated :)

[osrf-migration]

Original comment by Dave Hershberger (Bitbucket: dave_hershberger).

---

Well I've just spent my morning trying to understand why my robot's position was not initializing correctly.

I guess I'm not seeing the result of the "gzwarn" line for some reason, so I didn't find this until I looked at the Gazebo source.

So what's the status of the fix?

Is there any workaround? Redefine my URDF so that zero positions of joints are in other places, I guess? (ouch)

[osrf-migration]

Original comment by Tian X (Bitbucket: tmoneyx).

---

Try gazebo 1.9.

[osrf-migration]

Original comment by Andreas Bihlmaier (Bitbucket: andreasBihlmaier).

---

2.2 works, too.

[osrf-migration]

Original comment by John Hsu (Bitbucket: hsu, GitHub: hsu).

---

I am working on recovering it for 3.0. Current trajectory is going towards:

1. deprecate, recover and move JointController::SetJointPosition into Joint::SetPosition(unsigned int index, double position, double velocity = 0), which will recursively set all descendant links of a joint based on joint position specified. Operation fails if the parent link of the joint is a descendant link of the same joint (loop).
2. deprecate Joint::SetAngle by Joint::SetPosition.
3. update Joint::SetVelocity so it changes all downstream link states based on joint velocity specified (as implemented in Bullet). Currently ODE uses amotor, this need to be fixed.

[osrf-migration]

Original comment by John Hsu (Bitbucket: hsu, GitHub: hsu).

---

please see / test out pull request #1096

[osrf-migration]

Original comment by John Hsu (Bitbucket: hsu, GitHub: hsu).

---

@nkoenig
Is the bug mentioned in the ticket description about "updating the collision elements is not working" tracked by another issue or fixed?
Thanks.

[osrf-migration]

Original comment by Andreas Bihlmaier (Bitbucket: andreasBihlmaier).

---

Compiled gazebo from source (branch set_joint_position) together with gazebo_ros_pkgs.
After :%s/SetAngle(/SetPosition(/g in my gazebo plugins EVERYTHING WORKS at least as good as before (<= 2.2.2).
@hsu thank you very much

Once the patch is merged, will there be updated gazebo3 packages?

[osrf-migration]

Original comment by Nate Koenig (Bitbucket: Nathan Koenig).

---

@hsu I don't believe there was an issue tracking the "updating the collision elements is not working" problem.

@andreasBihlmaier Yes, we'll release a new debian of gazebo3.0 once this patch is in place.

[osrf-migration]

Original comment by Steve Peters (Bitbucket: Steven Peters, GitHub: scpeters).

---

• changed state from "new" to "resolved"

pull request #1096

[osrf-migration]

Original comment by Nate Koenig (Bitbucket: Nathan Koenig).

---

• set version to "all"

[osrf-migration]

Original comment by Nate Koenig (Bitbucket: Nathan Koenig).

---

• changed state from "resolved" to "closed"