In this exercise, the objective is to use a “grasp action client” to send a grasp goal that will open the gripper.
- In the main program, locate the function call to
- Go to the source file of that function by clicking in any part of the function and pressing F2 in QtCreator.
- Remove the first line containing the following
ROS_ERROR_STREAM ...so that the program runs.
Find every line that begins with the comment
Fill Code:and read the description. Then, replace every instance of the comment
ENTER CODE HEREwith the appropriate line of code.
/* Fill Code: . . . */ /* ======== ENTER CODE HERE ======== */
grasp_goal.goalproperty can take on three possible values:
grasp_goal.goal = object_manipulation_msgs::GraspHandPostureExecutionGoal::GRASP; grasp_goal.goal = object_manipulation_msgs::GraspHandPostureExecutionGoal::RELEASE; grasp_goal.goal = object_manipulation_msgs::GraspHandPostureExecutionGoal::PRE_GRASP;
Once the grasp flag has been set you can send the goal through the grasp action client
Build Code and Run¶
Compile the pick and place node:
Alternatively, in a terminal:
catkin build collision_avoidance_pick_and_place
Run the supporting nodes with the launch file:
roslaunch collision_avoidance_pick_and_place ur5_setup.launch
In another terminal, run your node with the launch file:
roslaunch collision_avoidance_pick_and_place ur5_pick_and_place.launch
If the task succeeds you will see something like the following in the terminal (below). The robot will not move, only gripper I/O is triggered:
[ INFO] [1400553290.464877904]: Move wait Succeeded [ INFO] [1400553290.720864559]: Gripper opened [ERROR] [1400553290.720985315]: detect_box_pick is not implemented yet. Aborting.