Constraint Satisfaction Problems: Formulation Brian C. Williams 16410-13 September 29th, 2003 Slides adapted fro 6. 034 Tomas lozano perez and AIMA Stuart Russell Peter Norvig Reading Assignments: Constraints Much of the material covered only in lecture slides

September 24, 2003 Scheme Tutor notes In scheme tutor stick to r5rs scheme The Tutor uses SCM, not miT scheme Strategy: click\Check\button on initial code, in order to view test cases pt.24,2003 16410/16413 Even more scheme

Out line Propositional Satisfiability Propositional Clauses Backtrack search Unit Propagation DPLL: Unit Propagation Backtrack Search Characteristics of dPLl local search using GSAT Propositional Clauses

Solving CsPs Solving CSPs involves some combination of 1. Constraint propagation eliminates values that cant be part of any solution 2. Search explores valid assignments Arc Consistency Arc consistency eliminates values of each variable domain that

Histol · Kautz and selman.1992 Inspired by improvements in satisfiabity algorithms Big Idea Encode planning problem as a(very large) logical formula Initial-state all-possible-actions goal Find a satisfying assignment to action-time propositions, and we have a plan

Assignment Reading Model-based Diagnosis-Lecture notes Propositional Logic AIMA Chapter 6 Problem set Model-based Diagnosis implementation Propositional Logic 16.413: Hello World implementation Due Monday, November 17th

WORLD observations Plant actions P(S sense act Diagnostic Agent Monitors diagnoses AGENT Repairs avoids Probes and tests

Integer Programs LP: Maximize 3x1+ 4x2 IP: Maximize 3x1+ 4x2 Subiect to: Subject te

Assignment problem Persons and tasks connected by links Objective: Minimize total task time minutes Carburetor Manny 4 minutes Valves

Robot Localization using SIR Take sample set X+_11 ll. iterate For each sample xt-1 1) Sample from p(X,1 X+1, a) 2) Attach importance weights