List of Planners Under Investigation

This page presents a list of planners Tim Fluharty is researching in order to understand the types of architectural components that are typically present in planners. See here for a page organized by components. Currently the research is focused on planners that use some heuristic to guide search through state-space.

Disclaimer: This page is for the author's benefit and not meant to be used for comparing or assessing planners. Summary descriptions of the planners, source code, and shortcomings may be inaccurate or the result of improper installation/execution. Summary descriptions may also be lifted from web pages and papers. Please e-mail corrections to the author. Wherever possible links to the planners, authors, and reference papers will be provided.

Each planner is summarized by the same features that are organized in tables. What is entailed in some of the non-obvious features is summarized here.
Automated or hand-coded This distinction was made in 2000 and 2002 competitions. Hand-coded planners will likely be omitted from Bus and not researched as thoroughly.
Versions Reports on changes for each version of the planner. Within each version the following will be reported (if applicable or if it changes from previous version).
  • Summary: (if a radically different version)
  • Capabilities: What planner supports
    • PDDL version
    • PDDL requirements (equality, typing, adl)
    • conditional effects
    • universal quantification
    • existential quantification
  • Competed: If it competed
  • Source: Source code availibility and dependencies
  • Comments: Personal comments about the source code (readability, structure, size, commenting etc.)
  • Problems: Any problems running the source code
  • Components: Major components and optimizations
  • References: References specific to that version of the planner.
Related planners Conceptually related planners or planners with code that the planner borrowed/adapted.
Added to Bus? What version is present in Bus (the metaplanner described here Reference)
Interesting Results Any domain or problem-specific results that may shed light on the research.

List:

Alphabetical By Competitions
AltAlt
GRT
STAN
1998
STAN
2000
AltAlt
GRT
STAN (Version 4)

Not Included:


Planners

AltAlt (A Little of This and a Little of That) Website

Authors
Automated or Hand-coded Automated
Brief summary AltAlt combines STAN's code that has a more efficient implementation of Graphplan and HSP-r's code to perform regression search.
Versions
  1. Version 1
    Capabilities: STRIPS
    Competed: 2000
    Source: C++ and Common Lisp versions available. C++ version requires flex and bison.
    Components:
Related planners
  • STAN's Graphplan (borrows code)
  • HSP-r's Regression search (borrows code)
Interesting Results
Added to Bus? Yes
References
  • "Planning Graph as the Basis for deriving Heuristics for Plan Synthesis by State Space and CSP Search." Reference This lengthy paper summarizes material covered in these three papers
    • "AltAlt: Combining the advantages of Graphplan and heuristic state search" Reference Overall description of AltAlt
    • "Extracting effective and admissible heuristics from the Planning Graph" Reference
    • "Distance based goal ordering heuristics for Graphplan" Reference


GRT (Greedy Regression Tables) Website

Authors
Automated or hand-coded GRT competed in both the automated and hand-coded divisions in the 2000 competition.
Classification Heuristic state space planner. Results of regressive heuristic calculated once and stored. Forward best-first search.
Brief summary
Versions
  1. Version 1
    Summary: Competition version with few extra features.
    Capabilities: STRIPS, no typing
    Competed: 2000
    Source: Available (but appears incomplete)
    Components:
  2. Version 2
    Summary: Several features added and now handles resources.
    Capabilities: (TODO)
    Competed: No
    Source: Available (but Clayton commented it didn't build)
    Components:
Related planners Similar to other heuristic planners such as HSP and its precursor ASP. Also, GRT is an extension of an earlier planner by the same authors called SSPOP.
Interesting Results
Added to Bus? No
References
  • "The GRT planning system: Backward heuristic construction in forward state-space planning." 2001Best summary of heuristic, added features, and results Reference
  • Exploiting State Constraints in Heuristic State-Space Planning 2000 Calculating and using XOR Constraints Referencel
  • "On Determining and Completing Incomplete States in STRIPS Domains" 1999 Describes completing goal states Reference
  • "GRT: A Domain Independent Heuristic for STRIPS Worlds Based on Greedy Regression Tables" 1999 An initial paper on GRT before many features are added Reference


STAN Website

Authors
Automated or hand-coded Automated
Brief summary STAN is a Graphplan style planner that has a more efficient way of constructing the planning graph. Searching beyond the fix point of the graph is also improved with the "wave front" mechanism. STAN also uses the TIM module to look for type structures and resource invariants.
Versions
  1. Version 1
    Capabilities: STRIPS
    Competed: 1998
    Source: Not available
    Components:
  2. Version 2
    Summary: Clean up of Version 1
    Source: Version 2/3 available
  3. Version 3
    Summary: Bug-fixes and several implementation improvements for greater efficiency.
    Components:
    • Kambhampati's EBL/DDB (TODO)
    • TIM module - symmetry. (TODO)
  4. Version 4
    Summary: A very different version of STAN that chooses between Graphplan style search of previous versions or forward heuristic search similar to FF or HSP.
    Capabilities: STRIPS, ADL?
    Competed: 2000
    Source: Only executable available. Authors warn of robustness issues and bugs.
    Components:
    • TIM module - action filtering (TODO)
    • Abstraction of sub-problems (path planning and resource handling)
Related planners
Interesting Results
Added to Bus? Version 4
References "Efficient Implementation of the Plan Graph in STAN." Reference

Last modified: Wed Sep 1 11:46:34 MDT 2004