Austin Tate's Nonlin Planning System

The Nonlin hierarchical partial-order AI planning system, developed by Austin Tate at the University of Edinburgh, is available in a browsable and downloadable form here: or thanks to Aaron Sloman at the University of Birmingham for encouraging Austin to make it it run as it used to in a much earlier version of Poplog, so that it works in both Windows Poplog and Linux/Unix Poplog.

Get a copy of the freely distributable version of Poplog at [PC/Windows version 15.5 is available locally here - note this version is only for a 32 bit Windows OS]. Unpack the files to a temporary location and run "SETUP.EXE". It may be best to allow the installer to place the files in the default sugegsted position to avoid any problems with spaces in directory names. You can then run Poplog POP-11 in a Window via the "Pop-11" shortcut created.

Fetch the file and unzip it in any directory you wish to use to try it out.


Some information on getting Nonlin up and running in recent versions of Poplog are in the readme.txt. Help to run the program is available in the on-line instructions. Further information, including sample problem domain definitions using the Nonlin task formalism (TF) can be found in the release zip file or can be browsed on-line here. A short video demonstration of Nonlin is available here.


Tate, A. (1976) "Project Planning Using a Hierarchic Non-linear Planner", D.A.I. Research Report No. 25, August 1976, Department of Artificial Intelligence, University of Edinburgh. [ PDF Format (6.75MB) ]

A review of this paper on Nonlin by Subbarao Kambhampati in 2002 is available here.

Tate, A. (1977) "Generating Project Networks", Proceedings of the Fifth International Joint Conference on Artificial Intelligence (IJCAI-77) pp. 888-893, Boston, Mass. USA, August 1977. Reprinted in "Readings in Planning" (eds. Allen, J., Hendler, J. and Tate, A.), Morgan-Kaufmann, 1990. [ PDF Format (1.5MB) ]

Other documents on Nonlin are available here.

A note by Austin Tate, written on 9-Jan-2008, on choice ordering mechanisms and heuristic search in Nonlin, O-Plan and I-X/I-Plan is available here.

Edinburgh University - Artificial Intelligence - Planning Systems

A leaflet describing applications of Nonlin and AI Planning work at Edinburgh's Planning Group, published in 1983, is available in PDF Format (2.5MB) and as a JPG Image (4.2MB)

UM Nonlin

The University of Maryland produced a Common Lisp version of some core parts of the Nonlin planner incorporating its hierarchical partial order approach to planning. See for more details and to download that version.


Brian Drabble's Ph.D project Excalibur planner was based on Nonlin and linked HTN planning methods with qualitative process reasoning. More details available on the Excalibur Planner Web Page

POP-2 Documentation and Manuals

Documentation and manuals for the original POP-2 system can be found here:


Nonlin is subject to the "Copyright Notice for Poplog and Associated Files and Packages" available at [also locally available here].