marip8
commented
1 year ago Do you think it might be possible to study reachability in a volume ? Instead of having a mesh and generating a point cloud on it, would it be possible to have just a point cloud in a volume and evaluate reachability in that point cloud ?
Definitely. The function of the TargetPoseGenerator interface is to allow the user to customize the generation of target waypoints for the reach study. The current implementations read point/normals from a .pcd file, but you could implement your own plugin to do this in the way you describe. See here and here for an example in c++ and here for an example in Python.
One other question I had is a more tricky one. I would like to study the reachability of a mobile manipulator that has two arms. Do you think it's possible with the package, and how ? Otherwise, do you think it's possible to do some tricks with the code in order to make this study possible ?
Yes, with some caveats; I've done this before with this robot. To use reach as-is, you'll need to:
- define a URDF with two prismatic joints (along x, y) and a revolute joint (about z) to move the mobile base
- define a motion group that includes these 3 joints and the joints of one of your robot arm(s) and an IK solver that can solve
- You might be able to define a motion group that includes both arms of the robot, but you may not find an IK solver that knows how to resolve both arms for a single target position (thinking specifically about MoveIt). You'll probably have to define two motion groups, where each includes only one of the arms, run two reach studies, and manually combine/compare the results.
FWIW, I'm running a workshop at ROSCon 23 where I plan to talk in more detail about customizing reach for use-cases that look significantly different than the one example in the repository. As a part of prep for that workshop, I can add some more documentation about plugin customization and additional examples, so keep an eye out for that and feel free to make suggestions for content
Thank you for providing this package to the community, it is very powerful and useful.
I have a question regarding the possibilities offered by the package.
Do you think it might be possible to study reachability in a volume ? Instead of having a mesh and generating a point cloud on it, would it be possible to have just a point cloud in a volume and evaluate reachability in that point cloud ? The idea I had to do it with a mesh is to have a vertical plane mesh, thin on the x axis, and doing the reachability study with this plane multiple times with a position further and further from the robot, and then compile all the results to make a volume.
Does it make sense according to you ?
One other question I had is a more tricky one. I would like to study the reachability of a mobile manipulator that has two arms. Do you think it's possible with the package, and how ? Otherwise, do you think it's possible to do some tricks with the code in order to make this study possible ?
Thank you for your help.