The UM Nonlin Planning System

Parallel Understanding Systems Group
Computer Science Department, University of Maryland at College Park


UM Nonlin is a Common Lisp version of Austin Tate's Nonlin planning system - a domain-independent, partial-order, hierarchical task network planner. UM Nonlin is available for public ftp (see below). The code is being distributed free of charge with no implied warranty or support.

UM Nonlin has been used for many domains. One of the more complex ones is UM Translog, a transport logistics planning domain.


The original Nonlin is described in detail in Project Planning Using a Hierarchic Non-Linear Planner by Austin Tate, Research Report 25, Dept. of Artificial Intelligence, University of Edinburgh, 1975.

A briefer description of Nonlin can be found in "Generating Project Networks" by Austin Tate in Readings in Planning (Eds. J. Allen, J. Hendler, & A. Tate), 1990.

The User Manual for UM Nonlin Version 1.2.2 describes how to use our implementation of Nonlin.

Mailing Lists

The following electronic mailing lists have been set up:


The latest "official" version of UM Nonlin is version 1.2.2 (Nov. 1992).

A "beta" version, UM Nonlin 1.3.5 (March 1995), is also available. This version has some minor fixes and is recommended for use with the UM Translog domain. The "beta" version, however, may still be somewhat buggy.

FTP'ing UM Nonlin

If you FTP Nonlin, please send mail to if you ftp Nonlin so we can keep you posted about bug fixes, updates, etc.

To FTP UM Nonlin, do the following:

  1. Choose the Release Version (version 1.2.2) or the Beta Version (version 1.3.5).
    (The beta version is recommended for use with the UM Translog domain. See notes above.)
  2. When prompted by Mosaic to save the BINARY file, enter the name nonlin-files.tar
  3. To extract the files, issue the UNIX command:
    tar -xvf nonlin-files.tar

To see the README file for FTPing UM Nonlin, click here.
(The FTP instructions in the README file apply only when FTPing via the UNIX FTP command. To FTP from Mosaic, follow the instructions above.)