LAPKT

Lightweight Automated Planning Toolkit

Miquel Ramirez [email protected] Nir Lipovetzky [email protected] Christian Muise [email protected] Last update: September 2014

CONTENTS

1. Overview of toolkit components
2. Building LAPKT
3. Search algorithms implemented
4. Examples
5. Contributing
6. Requirements

1 - OVERVIEW

LAPKT separates search engines from the data structures used to represent planning tasks. This second component receives the name of 'interface' since it is indeed the interface that provides the search model to be solved.

At the moment of writing this, the following interfaces are offered:

• 'agnostic': this interface does not depend on a particular planning language, so it is easy to wrap PDDL parsers, separating parsing representation of planning tasks from a representation optimized for off-line planning. This interface should also make easy to integrate STRIPS planners into applications by suitably defining planning tasks programatically.

• 'ff': this interface wraps FF parsing components to obtain 'agnostic' looking tasks. NOTE: this requires to compile the FF planner as a library. See the documentation on external/libff for instructions.

Future interfaces planned are:

• 'hsps': this interface wraps Patrik Haslum's HSP codebase, which supports parsing of PDDL 3.0 features.

• 'SAS+': this interface is meant to support SAS representations natively. Since there is no SAS-based planning language, this will probably be useful to integrate planners into applications that are able to define SAS planning tasks programatically.

Search engine components are meant to be modular, allowing users of LAPKT to assemble and combine features of different search engines to come up with customized search strategies, within reason and without sacrificing (much) efficiency. In order to do so, LAPKT makes heavy use of C++ templates and the Static Strategy design pattern. At the time of writing this, the modularity and decoupling of components isn't as high as I would like, there's still a lot of work to do :)

LAPKT is bound to change rapidly and dramatically over the next months, so please keep this in mind when using this library.

2 - BUILDING LAPKT

In order to build LAPKT you need to install scons (a GNU Makefile replacement) in your system. Refer to http://www.scons.org for directions on how to achieve this.

In order to compile some of the examples, you will also need a version >= 1.49 of the Boost C++ libraries available on your system. You can check the version you have either manually by looking at the macro defined in boost/version.hpp or, on debian systems, by running dpkg -s libboost-dev. Be aware that systems such as the Ubuntu 12.04LTS release ship with older versions of Boost.

Finally, LAPKT requires the Judy library (http://judy.sourceforge.net/index.html) to support the bitmap array class 'Varset Judy'. NOTE: This dependency will be optional or entirely deprecated in the future.

2.1. Build instructions

Issue the command

$ scons

at the root of the source directory to obtain the (static) library containing essential data structures and other miscellaneous utilities. If debug symbols are needed, the command

$ scons debug=1

builds the library with optimizations disabled and debug symbols enabled.

If you want to use the planners using the ff variants of our planners, you'll need to compile the FF sources included in this repository into a library by running the following commands:

cd external/libff
make clean
make depend
make

is achieved by invoking scons in a similar manner in the corresponding folder.

3 - EXAMPLES

3.1. AGNOSTIC INTERFACE EXAMPLES

The examples for the 'planner agnostic' interface can be found on

examples/agnostic-examples

and cover the following topics:

* agnostic-examples/assembling_strips_problems

	Shows how to define a STRIPS planning problem programatically.

* agnostic-examples/successor_generation
	
	Discusses the different way of generating successors during search.

* agnostic-examples/bfs
* agnostic-examples/bfs-double-queue 
* agnostic-examples/bfs-double-queue-secondary-heuristic

	Shows how can one assemble available components to deliver a
	planner built around a BFS search engine, with multiple queues and
	secondary heuristics, on a parametrized planning task.

* agnostic-examples/das

	Shows how can one assemble available components to deliver a
	planner built around Deadline Aware Search.

4 - REQUIREMENTS

LAPKT requires the following libraries: * boost::program_options * varjudy

In order to compile LAPKT, we recommend need g++ 4.6 or better. However, any compiler able to handle both boost libraries and C++0x standard new features, should also be usable (we have been able to compile it under Visual Studio 2010 and llvm).