Patent · US Expired

SAT-based image computation with application in reachability analysis

US6728665B1 · kind B1 · utility

15Cited by
4References
28Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 23, 2000
Grant dateApr 27, 2004
Priority date
Expiry dateAug 14, 2022

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F30/3323
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A method of performing image or pre-image computation for a system is disclosed. The method comprises representing the system by a finite state model; representing state sets using Binary Decision Diagrams (BDDs); performing a satisfiabilty checking (SAT) based backtrack search algorithm, wherein, the SAT decomposes the search over an entire solution space into multiple sub-problems, and wherein a BDD-based image computation is used to solve each sub-problem by enumerating multiple solutions from the solution space. Further, a method for pruning a search space in a SAT procedure is disclosed. The method comprises using BDD Bounding against an implicit disjunction or conjunction of a given set of BDDs; continuing search if a partial assignment of variables satisfies the implicit disjunction or conjunction, and backtracking if a partial assignment of variables does not satisfy the implicit disjunction or conjunction.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.