public static bool IsWithinDefaultSafetyRestrictions(Pose pose, out string firstBadStatement) { bool result = true; firstBadStatement = ""; Z3Body input = Z3Body.MkZ3Const(); Z3Body transformed = pose.Transform.Transform(input); BoolExpr transformedRestricted = pose.Restriction.Evaluate(transformed); var restrictions = Safety.DefaultSafetyRestriction().Restrictions; var composite = new CompositeBodyRestriction(); foreach (var restriction in restrictions) { composite.And(restriction); BoolExpr inputSafe = composite.Evaluate(transformed); BoolExpr expr = Z3.Context.MkAnd(transformedRestricted, inputSafe); SolverCheckResult solverResult = Z3AnalysisInterface.CheckStatus(expr); if (solverResult.Status == Status.UNSATISFIABLE) { firstBadStatement = ((SimpleBodyRestriction)restriction).Message; result = false; break; } } return(result); }
/// <summary> /// Checks if the pose is within default safety /// restrictions when the transform and restrictions /// are applied. /// </summary> /// <returns>True if it's safe</returns> public static bool IsWithinSafetyRestrictions(Pose pose, out Z3Body witness) { Z3Body input = Z3Body.MkZ3Const(); Z3Body transformed = pose.Transform.Transform(input); IBodyRestriction safe = Safety.DefaultSafetyRestriction(); BoolExpr inputSafe = safe.Evaluate(input); BoolExpr transformedRestricted = pose.Restriction.Evaluate(transformed); // Try to generate a unsafe witness using the transform BoolExpr outputUnsafe = Z3.Context.MkNot(safe.Evaluate(transformed)); // Put together all expressions and search for unsat BoolExpr expr = Z3.Context.MkAnd(inputSafe, transformedRestricted, outputUnsafe); SolverCheckResult solverResult = Z3AnalysisInterface.CheckStatus(expr); if (solverResult.Status == Status.SATISFIABLE) { //Z3Body witness = Z3AnalysisInterface.CreateBodyWitness( transformed, solverResult.Model, pose.GetAllJointTypes(), JointTypeHelper.CreateDefaultZ3Body()); return(false); } else if (solverResult.Status == Status.UNKNOWN) { //Z3Body witness = JointTypeHelper.CreateDefaultZ3Body(); return(false); } else { Contract.Assert(solverResult.Status == Status.UNSATISFIABLE); witness = null; return(true); } }
public static bool IsInternallyValid(Pose pose) { Z3Body input = Z3Body.MkZ3Const(); Z3Body transformed = pose.Transform.Transform(input); // We have to check that the pose is within the default safety restriction IBodyRestriction safe = Safety.DefaultSafetyRestriction(); BoolExpr inputSafe = safe.Evaluate(input); BoolExpr transformedRestricted = pose.Restriction.Evaluate(transformed); // Try to generate a safe witness using the transform BoolExpr outputSafe = safe.Evaluate(transformed); // Check to see if the transform is not satisfiable -- if so, then it is not internally valid BoolExpr expr = Z3.Context.MkAnd(inputSafe, transformedRestricted, outputSafe); SolverCheckResult solverResult = Z3AnalysisInterface.CheckStatus(expr); if (solverResult.Status == Status.SATISFIABLE) { // We can create a witness - therefore the pose must be valid return(true); } else if (solverResult.Status == Status.UNKNOWN) { return(false); } else { Contract.Assert(solverResult.Status == Status.UNSATISFIABLE); // Pose is not internally valid and as a result there can be no witness created return(false); } }