[Rock-dev] Assignment of a task to service by profiles

[Christian Rauch]

Hi,

I have a problem with the automatic assignment from a task to a service. 
The flavour is next.

I have the following Composition, that is writing on a command_in port 
of a Motion2DControlledSystemSrv (might be a robot or simulation):
{{{
class BaseMotion < Syskit::Composition
    argument :translation, :default => 0
    argument :rotation, :default => 0

    add Base::Motion2DControlledSystemSrv, :as => 'system'

     on :start do |ev|
        @cmd_writer = 
system_child.as(Base::Motion2DControlledSystemSrv).command_in_port.writer
     end

     poll do
         @cmd_writer.write(:translation => translation, :rotation => 
rotation) if @cmd_writer
     end

     on :stop do |ev|
         @cmd_writer.write(:translation => 0.0, :rotation => 0.0) if 
@cmd_writer
     end
end
}}}

In the profile (models/profiles/seekurjr/robot.rb), there is:
{{{
module Virgo
     module Profiles
         profile 'Robot' do
             [...]

             robot do
                 device(Dev::Platforms::MobileRobotics, :as => "seekur").
                     period(0.1).
                     frame('body')
		[...]
             end

             [...]

             use Base::Motion2DControlledSystemSrv => seekur_dev
             define 'base_motion', Virgo::BaseMotion.use('system' => 
seekur_dev)
}}}

where "Dev::Platforms::MobileRobotics" is defined by:
{{{
Dev::Platforms.device_type 'MobileRobotics' do
     provides Base::Motion2DControlledSystemSrv
     provides Virgo::BumperSrv
end

class Aria::Task
   driver_for Dev::Platforms::MobileRobotics, :as => 'device'
   [...]
end
}}}

That profile is selected in the action interface 
(models/actions/seekurjr/main.rb):
{{{
require 'models/actions/common_prediction'
require 'models/actions/common_base'

class Main < Roby::Actions::Interface
     use_profile Virgo::Profiles::Robot
     use_library Virgo::ActionsInterface
end
}}}

and (models/actions/common_base):
{{{
module Virgo
     module ActionsInterface
       action_library

     describe("Move forward with 0.25 m/s").
         returns(Virgo::BaseMotion)
     def fwd_025
         Virgo::BaseMotion.with_arguments(:translation=>0.25, 
:rotation=>0.0).as_plan
     end

     end
end
}}}


Now, if I execute "syskit run -r seekurjr fwd_025!" I expect that the 
service "Base::Motion2DControlledSystemSrv" is filled by Aria::Task 
automatically, as it is explicitly defined in the Robot profile (by 
seekur_dev) that is selected by the option "-r".

What I get is:
{{{
17:21:20.638 (Roby) cannot find a concrete implementation for 1 task(s)
17:21:20.638 (Roby) Syskit::TaskContext placeholder for 
Base::Motion2DControlledSystemSrv
17:21:20.638 (Roby)   3 candidates
17:21:20.638 (Roby)     Skid4Control::SimpleController,
17:21:20.638 (Roby)     Aria::Task,
17:21:20.638 (Roby) 
Base::ControlLoop/[controller.is_a?(Base::Motion2DControlledSystemSrv)]
}}}

Why is Aria::Task not automatically used? If I use the "base_motion_def" 
from the same profile, the Aria::Task is used as expected.
At the end, we want to switch profiles, where each profile defines what 
Task is providing the Base::Motion2DControlledSystemSrv.

Regards,
Christian


-- 
  Christian Rauch
  Space Robotics

  Universität Bremen
  FB 3 - Mathematik und Informatik
  AG Robotik
  Robert-Hooke-Straße 5
  28359 Bremen, Germany

  Tel:     +49 (0)421 178 45-6619
  Empfang: +49 (0)421 178 45-6611
  Fax:     +49 (0)421 178 45-4150
  E-Mail:  Christian.Rauch at dfki.de

  Weitere Informationen: http://www.informatik.uni-bremen.de/robotik