What's New Getting Started Tachyon User Manual

Screen shot (23k)

Tachyon is a constraint-based system for temporal reasoning, capable of reasoning about both qualitative and quantitative aspects of time. Tachyon is being developed at GE CR&D with partial funding from ARPA and US Air Force Rome Laboratory as part of their planning and scheduling initiative.
For a summary of some of our recent work, take a look at the slides from our recent talk at Rome Laboratory.


Sun OS 4.1.3
X11R4 or later
SUN SPARC series
Minimum of 32MB RAM, 1 GB Hard disk.


Prototype, has been integrated with several other prototype systems, available upon request.


User Guide, Tutorial, Object Description Document.


Jonathan Stillman
GE Corporate Research & Development Center

James Farley
GE Corporate Research & Development Center

Richard Arthur
GE Corporate Research & Development Center


Tachyon provides powerful temporal reasoning capabilities that can be applied effectively to a number of critical problems. We have concentrated on Tachyon's use in refinement and feasibility tracking of the temporal aspects of courses of action (projecting critical steps in a deployment plan to insure proper interaction between them), and on preserving temporal consistency during force package structuring and deployment (used in coordination with ForMAT and/or TPEdit, a TPFDD editor). We have also applied Tachyon to plan recognition tasks, where it was used to validate temporal sequencing of events as an aid in formulating plan hypotheses, to plan generation and monitoring, to scheduling for plastics and power systems manufacturing, and to retrieval and situation refinement in a prototype spatio- temporal data management system. Tachyon's constraint propagation capabilities were used there together with partial information about interrelated events to provide temporal refinement for tasking support. We have also developed a prototype integrating Tachyon with CAFE, GE's case-based reasoning system for constraint- directed force expansion.

Some of Tachyon's key features are summarized below:

Tachyon is provided with a graphical user interface (GUI) to facilitate interaction on a dynamic level. One can use Tachyon to test consistency of a network, fine tune it, or test it in ``What if...'' scenarios as desired, then save the network. The interface itself is a CAD-like direct-manipulation editor for the graphical representation of the underlying network. We have also isolated the interface itself to provide a generic graph editor library. Tachyon is available in a ``batch mode'' form, in which interaction is performed via text files (that may be created using the GUI or by another process).

As appropriate for the application. Tachyon takes as input a specification of a temporal constraint network that specifies events (tasks), windows of feasibility for events, and inter -event constraints. Currently, input is provided either via the GUI, files, or RPC communication from another process. Tachyon produces a refined version of the temporal constraints that expresses the maximal feasible times of occurrence of the events given the input constraints.

If you are already familiar with Tachyon: What's New
If you want to get it up and running: Getting Started
For more comprehensive information: Tachyon User Manual