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2018-10-29 21:40:55 -0500 asked a question How to reset Kuri using the ROS interface

How to reset Kuri using the ROS interface My Kuri is having trouble doing the hardware-reset (holding down power and up-

2014-08-11 12:42:39 -0500 answered a question How to get clusters location in tabletop_object_detector ?

The segmentation service just returns the points in the cluster. If you want a representative 'location' for the clusters, you might find the bounding box and use that. This service, for instance, can give you a bounding box based on 2-D PCA (z-axis is up, like you probably want on a table). (You want the non-3d version for table objects.)

https://github.com/ros-interactive-ma...

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2013-08-19 11:10:48 -0500 commented answer What happened to the Pick And Place Manager in groovy?

No plans, alas. It's likely you'll just have to pick one or the other forever. Sorry!

2013-08-18 20:24:23 -0500 commented answer What happened to the Pick And Place Manager in groovy?

BTW, make sure you do sudo apt-get remove ros-groovy-geometric-shapes before trying to install. There's a geometric_shapes dry package in arm_navigation that conflicts with the wet version used by MoveIt! so if you've installed MoveIt! on your computer, you'll have to uninstall it before arm_navigation will compile.

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2013-08-15 17:39:16 -0500 answered a question What happened to the Pick And Place Manager in groovy?

Pick and place manager has been updated and added back to branch groovy-devel in https://github.com/ros-interactive-manipulation/pr2_object_manipulation . Sorry it took so long! Hopefully you had good luck with MoveIt! in the meantime. :)

The pick and place manager will definitely not be in Hydro, in any event--arm navigation and all of that has been deprecated. Switch now if you can!

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2013-07-26 09:52:24 -0500 answered a question PR2 sensing question

The graspable objects in the pick_and_place_manager contain the point clusters, which have RGB information. These webpages will hopefully make it clear how to access that information: https://kforge.ros.org/Sushi/trac/wiki/Perception/PointCloud2InPython https://kforge.ros.org/Sushi/trac/wiki/Perception/PointCloud2MessageStructure

if you just take the average r and b values for the points in each object, you should be able to tell red from blue.

2013-06-13 09:57:50 -0500 answered a question What happened to the Pick And Place Manager in groovy?

I just didn't port it forward because we were planning to switch to MoveIt! imminently. The switch still hasn't happened, though, so it should be brought back. It wouldn't be hard to upgrade--just some of the messages have changed somewhat. If you have time to get to it now I'd be happy to merge a pull request with it. Otherwise I'll try to get to it eventually-soonish.

2013-05-30 19:05:01 -0500 commented answer Problem running pick and place application tutorial

Once that happens, check that pr2_object_manipulation is also green, and then try sudo apt-get upgrade to get the newest debs. Then hopefully things will work again. If not then comment here again.

2013-05-30 19:02:06 -0500 commented answer Problem running pick and place application tutorial

I'm guessing you're using the public repos (http://packages.ros.org/ros/ubuntu) then. When http://ros.org/debbuild/fuerte.html shows FbinP64 for perception_pcl having a green box (mouseover the green box should read ros/Public 1.2.4) then the new release of perception_pcl will be done building.

2013-05-28 17:58:27 -0500 commented answer Problem running pick and place application tutorial

There have been some build-farm compilation issues with compile flags lately, that might be causing the undefined-symbol problems you're seeing. Try just compiling and using object_manipulation and pr2_object_manipulation from source.

2013-05-28 17:55:28 -0500 commented answer Problem running pick and place application tutorial

Hrm. That's odd. Fuerte debians, latest version? Are you using shadow-fixed or public repos? What version of Ubuntu? 64-bit or 32-bit? I just tried using pr2_table_object.launch, both stereo:=true and stereo:=false, and both worked fine on my laptop.

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2013-05-25 11:30:42 -0500 commented answer Problem running pick and place application tutorial

You're using the stereo camera and looking at the table and it says Call to segmentation service failed? Any other error messages around it? Which ROS distro are you using?

2013-03-17 10:25:04 -0500 commented answer Anyone tried tabletop_object_detector for Kinect based pointclouds

Any point cloud will do. Just remap cloud_in to be your kinect point cloud. (Which you can generate by launching openni.launch in package openni_launch.)

2013-02-28 17:10:04 -0500 answered a question Object manipulation pipeline: how to motion plan with the hand, but grasp without it...?

That is odd. The table ought to be added to the planning scene separately, which would result in the gripper avoiding the table properly. Does the table show up as a polygon when you display the planning scene topic in rviz? If not, it's not being added to the planning scene. (You can add it using processCollisionGeometryForTable in collision_map_interface.cpp in the tabletop_collision_map_processing package.)

If the table is in the planning scene, then the move to the pre-grasp pose should be avoiding colliding with it. Disabling collisions between the grasp and the table is only done when checking for collisions with the final grasp pose, not the pre-grasp pose. So the pre-grasp pose should not be in collision with the table. We use move_arm to get to the pre-grasp pose, with collisions enabled between the gripper and the table, so there shouldn't be any collisions there.

2013-02-28 17:06:48 -0500 answered a question Object manipulator: how to lift upwards? (using different approach & lift directions for grasping)

Hm. Your message looks like it ought to be correctly specifying an upward lift. Is 'base_link' the robot_frame specified in your hand description file? If not, it won't let you use it as the frame (although it ought to throw an exception in that case).

If you set the min_distance and desired_distance to 0, it should disable the lift entirely, and you can just execute a Cartesian move upwards yourself. I often do an open-loop Cartesian move upwards if the grasp succeeded but the lift claims to have failed anyway, which happens fairly often with the PR2. (Also, setting min_distance and desired_distance to 0 is useful for grasping things like handles, where you really just wanted to close your gripper around the handle.)

2013-02-18 05:22:53 -0500 commented answer Most stable ROS version for running PR2?

Yup, Groovy/Precise.

2013-02-17 16:13:36 -0500 answered a question Problem running pick and place application tutorial

Is the robot looking at the table/object? Segmentation won't succeed otherwise. If you're in Fuerte or Groovy, you can use interactive manipulation to position your robot, see http://www.ros.org/wiki/pr2_pick_and_place_demos/Tutorials/The%20Pick%20and%20Place%20Autonomous%20Demo/

Also, this shouldn't have been a problem back in April 2012, but recently if you were using Fuerte + Kinect, there was a launch misconfiguration that was killing segmentation that is now fixed.

Sorry not to answer in a very timely fashion. All my ROS answers emails were getting spam-filtered. :P

2013-02-17 16:04:11 -0500 commented answer Most stable ROS version for running PR2?

Hm. Those are pretty out of date, aren't they? I just updated the pick and place autonomous demo tutorial: http://www.ros.org/wiki/pr2_pick_and_place_demos/Tutorials/The%20Pick%20and%20Place%20Autonomous%20Demo/ for Fuerte. Let me know if something still doesn't work.

2013-02-17 13:41:41 -0500 commented answer Most stable ROS version for running PR2?

which tutorials?

2013-02-17 12:40:13 -0500 answered a question Most stable ROS version for running PR2?

PR2 simulation in Groovy is still not the most stable. Would recommend sticking to Fuerte for now. I use Groovy on the real PR2, which is fine, but switch between Fuerte and Groovy still for simulation.

2013-02-06 15:28:22 -0500 answered a question Using object_manipulator on a non-PR2 robot

I patched object_manipulator in Fuerte trunk (0.6 branch) to make the plugin name a param. Please let me know if it doesn't meet your needs. (I'll release soon--Fuerte debs in shadow-fixed are all screwed up at the moment, waiting for that to be fixed.)

Sorry I didn't see your post until now--all ROS Answers emails were going straight to my spam folder. :P

2013-01-28 08:03:40 -0500 commented answer Gripper Grasp Planner Cluster - gripper model changes during grasp testing

btw, if your 'thumb' really is that short, unless it and the fingers actually move to cover the entirety of your blue grasping area, I would recommending making the blue grasping box at least a bit shorter.

2013-01-28 08:01:05 -0500 answered a question Gripper Grasp Planner Cluster - gripper model changes during grasp testing

I've seen that issue as well--as far as I can tell, it's an issue with tf and rviz visualization; it doesn't affect the actual grasp planning. I'm using a tf broadcaster to broadcast the object frame to draw the gripper model, and my guess is that there are issues with the timing of messages and which tf message rviz is using to draw various boxes. But I'm not using tf to transform the points into the wrist frame when computing collisions and points-in-the-grasp-box, so the actual grasp planning is unaffected by that.

2013-01-09 13:17:25 -0500 answered a question Which grasp planner to use, manipulation pipeline, non PR2 robot

If you look in the config folder in the pr2_gripper_grasp_planner_cluster package, you can see the config files I made for the Schunk hand and for the RobotIQ hand (as well as the one for the PR2). If you want to use the cluster planner, you just have to make one for your hand--it specifies axis-aligned boxes (relative to the frame you want the pose for when defining a grasp in the world, which for the PR2 is the wrist roll link frame) that denote spaces where there shouldn't be any points (because your hand takes up that space) and space where there should be points (because that means there's something inside your hand). And a few other params whose explanation is in the code. (Sorry there isn't better documentation. If you need help with that, just email.)

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2012-08-15 16:51:14 -0500 commented answer Problem installing tabletop_object_perception package

Good point. I added notes to both wiki pages, along with the urls for Electric and Fuerte code.

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2012-08-09 15:10:56 -0500 answered a question problem with pick and place application tutorial

Hm. Stuff seems to work fine for me out of current Electric debians, launching pr2_table_object.launch in manipulation_worlds and then pr2_tabletop_manipulation.launch.

You do have to move the arms to the side first if you use that simulation, which that particular tutorial doesn't address. If you rosrun pr2_pick_and_place_demos pick_and_place_demo.py, then use the commands 'r', 'j', 'l', 'j' (right-arm move-to-side, left-arm move-to-side), it'll get both arms off to the side, then you can quit and run the tutorial code. Although there does seem to be an issue with the fingertip contacts jittering and causing the grasp to 'fail', which you can ask the code to ignore because it's actually fine (which is what we do in the pick and place demo), but that tutorial doesn't, alas.

Are you using the standard Electric debians? Do you have any code overlays?
Also, what is that simulation world you are launching?

2012-07-14 13:09:29 -0500 answered a question problem with pick and place application tutorial

Sounds like the collision map processing service crashed? There's not nearly enough info to tell what happened. Does this happen every time you run? Simulated or real robot? Electric or Fuerte? Did you launch the robot and pr2_tabletop_manipulation.launch first?

If you post a copy of the entire terminal output from where you launched pr2_tabletop_manipulation.launch and also where you ran the tutorial program online someplace and put a link in your comment, I'll take a peek and give you my best guess about what's going wrong.

2012-07-14 13:08:56 -0500 answered a question problem with pick and place application tutorial

Sounds like the collision map processing service crashed? There's not nearly enough info to tell what happened. Does this happen every time you run? Simulated or real robot? Electric or Fuerte? Did you launch the robot and pr2_tabletop_manipulation.launch first?

If you post a copy of the entire terminal output from where you launched pr2_tabletop_manipulation.launch and also where you ran the tutorial program online someplace and put a link in your comment, I'll take a peek and give you my best guess about what's going wrong.

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2012-05-08 13:36:27 -0500 answered a question pr2 Keeps Dropping Objects

The object wiggles out of the robot's grasp because ODE's simulation of contacts is not very realistic. You can add John Hsu's grasp hack to the object to make it much harder to drop the object--when both fingertips have contacted the object for some number of seconds, it records the relative pose between the object and the gripper and keeps warping the object back there until the gripper opens and lets go. (Sometimes the object still falls if you move around too fast or hit the world with it, but that's actually more realistic than otherwise.)

Look at cup.urdf in manipulation_worlds/urdf, in stack pr2_object_manipulation, for an example of how to add the grasp hack to an object.

2012-05-08 13:36:06 -0500 answered a question pr2 Keeps Dropping Objects

The object wiggles out of the robot's grasp because ODE's simulation of contacts is not very realistic. You can add John Hsu's grasp hack to the object to make it much harder to drop the object--when both fingertips have contacted the object for some number of seconds, it records the relative pose between the object and the gripper and keeps warping the object back there until the gripper opens and lets go. (Sometimes the object still falls if you move around too fast or hit the world with it, but that's actually more realistic than otherwise.)

Look at cup.urdf in manipulation_worlds/urdf, in stack pr2_object_manipulation, for an example of how to add the grasp hack to an object.