[ros-users] how to use pr2_controller_manager with a different robot

[Wim Meeussen]

Adam,

I only found an old and out-of-date configuration file. So this will
not work, but might help you in coming up with a working
configuration. To find out what exactly you need, take a look at the
init method of the controller.

  <group ns="r_arm_cartesian_pose_controller" clear_params="true">
    <param name="type" type="string" value="CartesianPoseController" />
    <param name="root_name" type="string" value="torso_lift_link" />
    <param name="tip_name" type="string" value="r_gripper_tool_frame" />
    <param name="output" type="string"
value="r_arm_cartesian_twist_controller" />

    <param name="fb_trans/p" value="800.0" />
    <param name="fb_trans/d" value="12.0" />
    <param name="fb_rot/p" value="80.0" />
    <param name="fb_rot/d" value="0.0" />
  </group>


Wim



On Tue, Aug 31, 2010 at 6:29 PM, Adam Leeper <aleeper at stanford.edu> wrote:
> Thanks Wim.
>
> If robot_mechanism_controllers/CartesianPoseController is generic, is there
> a sample config or launch file for setting the parameters? Sachin sent one
> out earlier for JTTeleop, but I guess that is pr2-specific.
>
> Thanks.
>
>
> Adam Leeper
> Stanford University
> aleeper at stanford.edu
> 719.358.3804
>
>
> On Tue, Aug 31, 2010 at 6:17 PM, Wim Meeussen <meeussen at willowgarage.com>
> wrote:
>>
>> > When I launch and try to check the status of the controllers using
>> > pr2_controller_manager list, it hangs and if I kill it the traceback
>> > says it
>> > was waiting for 'pr2_controller_manager/list_controllers.' When I run
>> > the
>> > pr2 in gazebo, that service is advertised by gazebo itself... so
>> > obviously I
>> > have a problem.
>>
>> The pr2 controller manager is a library, not an executable. So when
>> you run in simulation, Gazebo creates the controller manager, and when
>> you run on the pr2, pr2_ethercat creates the controller manager.  When
>> you launch "controller_manager.launch", this will only load the
>> configuration for the controller manager on the parameter server, and
>> run some supporting nodes (diagnostics, state publisher, etc), but
>> this will not run the controller manager. Take a look at the
>> pr2_etherCAT package for an example on how to start the controller
>> manager.
>>
>>
>> > What is the correct procedure for interfacing my own hardware with ros?
>> > I
>> > know at some point I need to hook all this up to actual joint data
>> > coming in
>> > off my hardware. Can someone point me to an example of how that is
>> > published? Also, do the CartesianPoseController and JTTeleopController
>> > work
>> > with a generic urdf, or are they pr2-specific?
>>
>> There are multiple ways to do this:
>>  * You can create a ROS node for each piece of hardware, and allow
>> other nodes in your system to interact with the hardware over
>> topics/services/actions. This is a very easy approach. The
>> disadvantage is that you won't be able to create a closed loop in hard
>> realtime, and you won't be able to reuse the controllers we built for
>> the PR2. But I would think that most people have used this approach
>> when porting their robot to ROS.
>>
>>  * You can implement the hardware interface (pr2_hardware_interface)
>> for your hardware, and use the controller manager. The pr2 hardware
>> interface is however PR2 specific, so this approach will only work for
>> robots that are in some ways similar to the PR2. The hardware
>> interface for example only supports effort controlled joints.  All the
>> controllers we built, are using the "JointState" object of the
>> hardware interface. So, take a look at the class, and see if you could
>> implement this for your robot.
>>
>> The controllers that are not PR2 specific live in stacks that don't
>> have the pr2-prefix. The robot_mechanism_controllers package for
>> example contains a set of non-pr2-specific controllers.
>>
>>
>> Hope this helps,
>>
>> Wim
>>
>>
>>
>>
>> --
>> --
>> Wim Meeussen
>> Willow Garage Inc.
>> <http://www.willowgarage.com)
>> _______________________________________________
>> ros-users mailing list
>> ros-users at code.ros.org
>> https://code.ros.org/mailman/listinfo/ros-users
>
>



-- 
--
Wim Meeussen
Willow Garage Inc.
<http://www.willowgarage.com)