MoveGroupCommander unable to connect to move_group action server

edit

Hi there,

I'm using ROS indigo and was trying to initialize a MoveGroupCommander but got an error. Below is my code:

self._moveit_group = movie_commander.MoveGroupCommander('arm')

And this is the error message:

RuntimeError: Unable to connect to move_group action server 'pickup' within allotted time (5s)

However, the move_group/MoveGroupPickPlaceAction is showing up in the terminal of move_group.launch, and also shows up when I did rosparam get /move_group/capabilities. I really don't know what the problem is.

I know this error is similar to this question, but in my case the error is caused by the MoveGroupCommander instead of Rviz.

Can anyone please help? Thank you soooo much!