One of the difficult problems in robotics is to define a path for the motion of a robot's arms to grasp an object, especially when obstacles may obstruct the most obvious path of motion. Fortunately, a ROS package called MoveIt allows us to plan and execute a complicated trajectory.
A video created at Rethink Robotics shows how to use MoveIt to plan the motion of Baxter's arms and then have MoveIt actually cause a real or simulated Baxter to execute the motion. To see the video, go to https://www.youtube.com/watch?feature=player_detailpage&v=1Zdkwym42P4.
A tutorial is available at the Rethink wiki site at http://sdk.rethinkrobotics.com/wiki/MoveIt_Tutorial.
First, start the Baxter simulator in Gazebo:
$ cd baxter_ws $ ./baxter.sh ...