Action API

The opendoors node provides an implementation of a SimpleAcionServer (see actionlib documentation), that take in goals containing opendoors/GraspHandleGoal messages. You can communicate with the move_arm node over ROS directly, but the recommended way to send goals to move_arm if you care about tracking their status is by using the SimpleActionClient. Please see actionlib documentation for more information.

Downloading

The opendoors package is a part of the mit-ros-pkg repository. To download the most recent version of the stack without downloading the whole repository use

svn co `roslocate svn opendoors`

Tutorials

The tutorials for this package are in the GraspHandleAction tutorial

Videos

In this video, the PR2 first finds the position the handle of the cupboard by using point clouds from its laser scan. Then, it moves it gripper 10cm away from where it thinks the cupboard handle is and opens it gripper to prepare to grasp the handle. Then moves the arm 10cm forward to get to the handle, where it finally closes the gripper.

Here, PR2 is opening the cupboard door from a position where its right elbow is to the right of the robot and its arm is bended.

Here, PR2 is opening the cupboard door from an initial arm configuration in which PR2's shoulder joint is forced to move while bending the arm to open door.

Improvements

GraspAction is a simple action server that basically relies on move_arm action service. In order to improve it to a complex action server that people can use to open an cupboard, it is recommended that force controller be used. One can use ee_cart_imped_action, which is a nicely implemented force and torque controller for the arms of PR2. Secondly, to make the action server robust a loop controller can be used. A simple loop controller may adjust the force applied on PR2 arms based on the position of the arms relative to the frame of the cupboard being opened. For simple tracking purpose, tf package can be used. Thirdly, the suggestions above can be made into an action server along with the GraspHandle and tabletop_for_cupboard (object detection action that is specifically designed to work with opening cupboards) action servers to make one robust action service that works well with any type of cupboard or doors.