Toolkit for approximating and Adapting POMDP solutions In Realtime (TAPIR)

TAPIR [1] is a C++ implementation of the Adaptive Belief Tree (ABT) algorithm [2]. ABT is an online POMDP solver capable of adapting to modifications to the POMDP model without the need to reconstruct the policy from scratch. For continuous action spaces, TAPIR also includes an implementation of General Pattern Search in Adaptive Belief Trees (GPS-ABT) [3].

[1] D. Klimenko and J. Song and. H. Kurniawati. TAPIR: A Software Toolkit for Approximating and Adapting POMDP Solutions Online. Proc. Australasian Conference on Robotics and Automation. 2014. [pdf]

[2] H. Kurniawati and V. Yadav. An Online POMDP Solver for Uncertainty Planning in Dynamic Environment. Proc. Int. Symp. on Robotics Research. 2013. [pdf]

[3] K. Seiler and H. Kurniawati and S.P.N. Singh. An Online and Approximate Solver for POMDPs with Continuous Action Space. Proc. IEEE Int. Conference on Robotics and Automation (ICRA). 2015. [pdf]

For the latest news, please visit the TAPIR website.

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TAPIR Development Team

• Main developers:
  • Dimitri Klimenko (core toolkit)
  • Konstantin Seiler (continuous action spaces)
  • Joshua Song (ROS + VREP interface)

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System Requirements

Operating systems: Linux.

Building and running the C++ source code requires:

• GNU C++ compiler (>= 4.8) or equivalent
• libspatialindex (>= 1.7.0) Debian/Ubuntu package name: "libspatialindex-dev"

Ubuntu 12.04 NOTE:

Ubuntu 12.04 by default ships with g++ 4.6. One option is to replace g++ 4.6 with g++ 4.8. Otherwise, to have both g++ 4.8 and g++ 4.6:

sudo add-apt-repository ppa:ubuntu-toolchain-r/test
sudo apt-get update
sudo apt-get install g++-4.8
sudo update-alternatives --install /usr/bin/g++ g++ /usr/bin/g++-4.8 60
sudo update-alternatives --install /usr/bin/g++ g++ /usr/bin/g++-4.6 40

Here, 4.8 priority is set to 60, higher than 4.6. To swap to 4.6 use:

sudo update-alternatives --config g++

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Quick Start (Command-line Interface)

TAPIR with command-line interface has been tested with Ubuntu 12.04 -- 14.04.

Setup and Installation

At the top level directory of TAPIR (where this README file is located), run:

make all

or, for faster compilation via multi-threading,

make all -jN

where N is the number of threads you want to use - 8 is a good choice on many CPUs.

This will create the executables for a command-line interface for each of the example problems - these are created in problems/[problem-name], and also in src/problems/[problem-name] for convenience while editing the source files.

Running

After compiling, you can try the following commands to try using TAPIR on RockSample, which is a well-known example POMDP:

cd problems/rocksample
./simulate --no-load

This runs the simulator starting with an empty policy, with all of the calculations being done online during the simulation. To pre-generate an initial policy and use it as the starting point for a simulation, you can use the "solve" executable, i.e.

cd problems/rocksample
./solve
./simulate

You can also run RockSample[11,11], a version of RockSample with a larger map and much larger state space, by using the command-line setting --cfg default-11-11.cfg, i.e.

cd problems/rocksample
./simulate --no-load -cfg default-11-11.cfg

The command "solve" uses the parameters set in a problem-specific configuration file, which for RockSample is, by default, here. The purpose of "solve" is to output a policy, which by default will be written to the file "pol.pol" in the current working directory.

The command "simulate" uses the same default configuration file, but its function is to run online simulations to evaluate the performance of the TAPIR solver. By default it starts by loading an initial policy from the policy file (default "pol.pol"), but with the argument "--no-load" it begins with an empty policy instead. Following this, "simulate" runs a step-by step simulation of the POMDP. The online solver is run on every step so that the policy can be dynamically generated on every step.

Changing Configuration Files

To change the configuration settings, edit the default configuration files, or copy them and make your own version, e.g.

cd problems/rocksample
cp default.cfg my_settings.cfg

Now you can edit my_settings.cfg to change the settings. To use with a different configuration file, use the command-line argument --cfg, e.g.

cd problems/rocksample
./solve --cfg my_settings.cfg

Note that "solve" is still searching for configuration settings in the directory "problems/rocksample" - you can change this by using the argument --base-path <path>.

Other Options

Some of the core settings can also be set via command-line arguments. Any command-line options given will override the values specified in the configuration file. For details, run

./solve --help

or

./simulate --help

to see the command-line options for either executable.

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Quick Start (ROS and V-REP Interface)

TAPIR provides an interface with ROS and V-REP, tested on:

• Ubuntu 12.04 with ROS Hydro + V-REP PRO EDU V3.1.2.
• Ubuntu 14.04 with ROS Indigo + V-REP PRO EDU V3.1.2.
• Ubuntu 16.04 with ROS Kinetic + V-REP PRO EDU V3.3.2.

Additional system requirements

ROS

Go here for instructions on how to install ROS. Some possible issues and ways around them are:

• Ubuntu 12.04: ROS Hydro defaults to using Boost 1.46 instead of Boost 1.48, and the Boost 1.48 headers are incompatible with C++11 (as used by TAPIR). To resolve this issue, you will need to install Boost 1.48 from source. The easiest way to set up Boost 1.48 for use with ROS and TAPIR is, at the top level directory of TAPIR, to do the following:

  1. Set CUSTOM_BOOST_148_DIR in the root Makefile to the location of your Boost 1.48 installation, or, if you haven't installed it yet, the desired directory for it (e.g. ~/vrep)
  2. Run the command make boost

  The command make boost will find if a Boost installation is in CUSTOM_BOOST_148_DIR. If it doesn't find a Boost installation, it will automatically download Boost and install it to the directory you've specified at CUSTOM_BOOST_148_DIR. It will also patch a bug in the Boost headers that causes problems with GCC >= 4.7.0. These functions are performed by several scripts in the .ros-scripts directory.

  If you wish to compile Boost 1.48 manually with GCC >= 4.7.0, you should use the patch provided here.

• Ubuntu 14.04: On Ubuntu 14.04 you must instead use ROS Indigo, which is available via the package "ros-indigo-desktop-full"

V-REP

Go here, download V-REP, and extract it to the directory of your choice. TAPIR has been tested with V-REP PRO EDU V3.1.2.

• Ubuntu 14.04: On Ubuntu 14.04 the version of the ROS plugin that ships with V-REP will not work out of the box - it causes a segmentation fault in V-REP! You will need to recompile the plugin.

V-REP ROS plugin

V-REP comes with a plugin for ROS, but the default version of this plugin may not work properly for you - in particular, the current distribution of V-REP is not designed for ROS Indigo, and so if you're on Ubuntu 14.04 you will need to rebuild it.

TAPIR comes with a script to automatically recompile the V-REP plugin for you, which can be run using the command

make vrep_plugin

Note that this requires you to set the VREP_DIR and ROS_SCRIPT variables in the root Makefile before it will work properly. The script should automatically rebuild the plugin and copy it to VREP_DIR.

If you instead wish to manually rebuild the plugin, follow the tutorial here. To do this on Ubuntu 14.04, you will also need to change line 14 of
VREP_DIR/programming/ros_packages/vrep_plugin/CMakeLists.txt to
link_directories("/opt/ros/indigo/lib")
instead of
link_directories("/opt/ros/hydro/lib")
Please note that the V-REP plugin also requires the ROS joystick packages in order to compile - for ROS Indigo those packages should be available via the Ubuntu/Debian package ros-indigo-joy.

Setup and installation (for use with ROS and V-REP)

This package is designed to be used with the ROS Catkin build system, and as such must be compiled within a Catkin workspace. To do this, start at the top level directory of TAPIR (where this README file is located) and do the following:

1. Set the following variables in the root Makefile :
   • CUSTOM_BOOST_148_DIR - A custom path to Boost 1.48; leave this empty if you just want to use your system default version of Boost.
   • ROS_SCRIPT - path to the main ROS setup script; the default is /opt/ros/hydro/setup.sh
   • CATKIN_WS_DIR - path to the desired Catkin workspace directory; the default is ../catkin_ws (relative to the root tapir directory, i.e. the location of this README)
   • VREP_DIR - path to where you have extracted V-REP; the default is ../vrep
2. Run the command make ros

The command make ros can automatically set up a workspace for you and will add a symbolic link to the source directory into the workspace.

Running (with ROS and V-REP)

If you compiled with make ros, TAPIR will automatically create a script to run the Tag example problem together with the ROS and V-REP interface. To run Tag with ROS+VREP, go to the top level directory of TAPIR (where this README file is located), and run the following commands:

cd problems/tag
./simulate-ros

The script simulate-ros will automatically run a roscore, and then launch V-REP (if it is not already running). Note that the roscore must already be running when you start V-REP, or the ROS plugin will fail to load; it is also important to read the console messages when V-REP is staring up in order to make sure that the ROS plugin loads correctly. If there is an issue with loading the ROS plugin, you may need to recompile it - follow the instructions in the previous section on the V-REP plugin.

If you run a roscore and launch V-REP manually, and have sourced the setup script for your Catkin workspace, i.e.

source [path/to/catkin/workspace]/devel/setup.bash

you can simply run

roslaunch tapir tag.launch

in order to start the Tag problem.

After a couple of seconds, the simulation should start automatically; it can also be paused at any time via the V-REP interface. During the simulation you can also actively manipulate the environment using the mouse to left-click on squares in the Tag grid:

• To remove an obstacle, left-click on a cell and wait momentarily.
• To add an obstacle, left-click on a cell and wait momentarily.
• You can also add or remove multiple cells at the same time by holding down the CTRL key while clicking on those cells.

Interface details

Additional detail on how to interface with ROS and V-REP when implementing your own POMDP problems is provided in in the ROS/V-REP Guide.

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Implementing a new POMDP model

To create a new POMDP model and use it with the the command-line interface,

1. Read the README on implementing a new model

2. Create a new subdirectory for your POMDP in the problems directory

3. Implement all the required classes, as per the new model README

4. Add a new Makefile to your problem directory - just copy the Tag Makefile and change MODULE_NAME to match your new problem.

5. Add your problem to the CHILD_DIRS variable in the problems Makefile

6. Create a new subdirectory in the config directory for your problem, and add any required configuration files there.

7. Compile your code via make [problem-name], or simply by running "make" from your new subdirectory of src/problems, e.g.

    cd src/problems/tag
    make
   

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Acknowledgements

The development of this package is partially funded by the University of Queensland BEE Division Grant 2013 and the BME Early Career Researcher 2014 to Hanna Kurniawati.

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Release Notes