Add cartesian_wrench controller to default_controllers.yaml

[708yamaguchi]

I added cartesian_wrench controller to default_controllers.yaml, because it is not listed in the yaml file.
The source code of cartesian_wrench controller exists in https://github.com/fetchrobotics/robot_controllers/blob/indigo-devel/robot_controllers/src/cartesian_wrench.cpp

[mikeferguson]

Have you tested this? Some controllers exist in the source, but haven't really ever been tested (which is why there weren't included). We debugged the Twist controller two summers ago with an intern, but I don't recall ever actually testing the wrench controller after porting it into robot_controllers.

[708yamaguchi]

I used cartesian_wrench controller on real fetch robot, and it actually moved.

In this link, I attach the movie in which our fetch robot moves its arm with cartesian_wrench controller.
https://drive.google.com/open?id=148utU3KsMGwQbQssEGhK5nY-i5ejOPmo

This is the source code which is used in the movie.

#!/usr/bin/python

import rospy
from geometry_msgs.msg import Wrench
import numpy as np


rospy.init_node('cartesian_wrench_test')

pub = rospy.Publisher('/arm_controller/cartesian_wrench/command', Wrench, queue_size=1)
msg = Wrench()
i = 0
while not rospy.is_shutdown():
    msg.force.x = 50 * np.sin(np.deg2rad(i * 30.0))
    msg.force.y = 50 * np.cos(np.deg2rad(i * 30.0))
    pub.publish(msg)
    rospy.sleep(0.1)
    i += 1
    i %= 360

However, I am not sure whether this is the desired motion.
If you have any idea, could you please tell me how to test the cartesian_wrench controller?

[moriarty]

@erelson perhaps you & @aparker-fetch would want to test/review this before we accept/merge it?

[moriarty]

https://translate.googleusercontent.com/translate_c?depth=1&rurl=translate.google.com&sl=ja&sp=nmt4&tl=en&u=https://github.com/jsk-ros-pkg/jsk_demos/issues/1255

@708yamaguchi we still haven't gotten around to testing this sorry.
Are you running Kinetic or Indigo on your Fetch?

We're preparing to announce the upgrade process to Melodic, and things are currently in ros-shadow-fixed but they're not ready for use yet... (ros/rosdistro#20397 we're still finding small issues)

[moriarty]

@708yamaguchi sorry this didn't get into Indigo before the Indigo End of Life date.

Do you plan to move to Melodic?

[708yamaguchi]

For the time being, our Fetch robot continues to be indigo.

I am sorry, but I will not be able to test this Pull Request on melodic.

[moriarty]

@708yamaguchi okay no problem.

I’ll put it on our backlog.