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ow_autonomy

This package contains a candidate onboard autonomy component for an Ocean Worlds lander, namely a ROS node embedding a PLEXIL application.

It's called the autonomy node, and only one instance of this node in an OceanWATERS application/mission is envisioned at this time.

Contents

src/plans directory contains the PLEXIL plans.

src/plexil-adapter contains the supporting code needed to run them, and also the ROS node implementation (for now).

See the README files in each subdirectory for more information.

Build

A prerequisite for building and running this application is a working PLEXIL installation, which has its own prerequisites. For instructions see the "Development Environment" Confluence page. The environment variable PLEXIL_HOME must be set to PLEXIL's installation pathname.

Your ROS environment should also first be set up:

 source <catkin-workspace>/devel/setup.sh

Assumed is this directory filed properly within an OceanWATERS ROS workspace (see Conftluence for instructions). Build the entire workspace with:

 catkin build

Build just the ow_autonomy package with:

 catkin build ow_autonomy

NOTE: If any new PLEXIL plans (.plp or .ple files) have been added since your last build, a clean rebuild of ow_autonomy is needed. See bottom of this file for instructions.

Run

1. Start the simulator:

  roslaunch ow europa_test_dem.launch arm_sim_enable:=true

NOTES: - for faster performance, add gzclient:=false - for even faster performance, gazebo:=false - for better terrain, use europa_terminator.launch

2. (optional, as needed) Start rqt for visualization and monitoring.

   rqt

   If you wish to view camera images:

   a) Select Plugins/Visualization/Image View b) In the topic pulldown menu, select /StereoCamera/left/image_raw

   Note that /StereoCamera/left/image_raw_mouse_left appears in the box below.

3. Start the autonomy node. To use the default plan:

   roslaunch ow_autonomy autonomy_node.launch

   This invocation loads the default PLEXIL plan, Demo.plx, which demonstrates a variety of lander functions: arm planning, guarded move, publishing trajectory (for Gazebo), and panoramic imaging. It is equivalent to:

   roslaunch ow_autonomy autonomy_node.launch plan:=Demo.plx

   Alternatively, you may specify a plan to load, by setting the 'plan' argument to a .plx file found in:

   <ow_workspace>/devel/etc/plexil

Plans

Here are some interesting autonomy plans. Run them as shown, substituting for Foo.plx:

roslaunch ow_autonomy autonomy_node.launch plan:=Foo.plx

1. The Europa reference mission Sol 0 prototype: EuropaMission.plx

   At present, this plan is stubbed except for the (shortened) panoramic landing site imaging that happens near the beginning.

2. A short panoramic imaging demo: TestAntennaCamera.plx

   A small area is imaged, with an iteration of tilts and pans. To try other regions, edit ow_autonomy/src/plans/TestAntennaCamera.plp and enter

   catkin build ow_autonomy

   before restarting the autonomy node. You don't need to restart the simulator.

3. Overtorque detection: TorqueTest.plx

   This plan attempts to push the scoop into the ground, which creates joint over-torquing warnings and errors.

4. Concurrency demo: TestPlanning.plx

   This runs the arm planning ROS service, while concurrently printing an "in progress" message. This was not possible before service calls were threaded.

5. ROS Action demo: TestActions.plx

   This runs a dummy GuardedMove action (not connected to simulator) concurrently with the real GuardedMove service.

Fault Detection

A rudimentary version does nothing more than check relevant fault parameters for each lander operation. Run any plan you like, while setting fault parameters as desired (see ow_faults/README.md for instructions). Faults are reported as ROS warnings -- that's all for now.

Clean

To clean (remove all build products from) just the ow_autonomy package:

cd <ow_workspace>/build rm -rf ow_autonomy

To clean the entire ROS workspace (not needed if you're just rebuilding ow_autonomy):

catkin clean