Open Gripper¶

In this exercise, the objective is to use a "grasp action client" to send a grasp goal that will open the gripper.

Locate Function¶

In the main program , locate the function call to '''application.set_gripper()'''.
Go to the source file of that function by clicking in any part of the function and pressing "F3".
Remove the fist line containing the following '''ROS_ERROR_STREAM ...''' so that the program runs.

Complete Code¶

Find every line that begins with the comment "''Fill Code: ''" and read the description. Then, replace every instance of the comment "''ENTER CODE HERE''"with the appropriate line of code.

/* Fill Code: 
     .
     .
     .
*/
/* ========  ENTER CODE HERE ======== */

The 'grasp_goal' goal property 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 in QT

Project -> Build Project

Alternatively, in a terminal cd into the '''demo_manipulation''' directory and do the following

catkin build collision_avoidance_pick_and_place

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.

API References¶

sendGoal()

Open Source Feedback

See something that needs improvement? Please open a pull request on this GitHub page