Assembly order stops needing after-the-fact repair: a constraint-preserving planner returns the exact best remaining sequence in all 128 recoverable disturbance cases
In modular assembly the robot's task order must respect assembly precedence and be reordered when conditions change after work begins. Constraint-Aware Genetic Task Planning (CGTP) keeps initialization and variation inside the precedence-feasible region and, on replanning, freezes completed operations and re-optimizes only the remaining task graph. On an exhaustively verifiable eight-task benchmark it returned the exact best feasible suffix in all 128 structurally recoverable scenarios and flagged all 3 unrecoverable ones; on a 90-instance corpus, per-class recovery ran from 0.881 to 1.000 with no budget-conditional search failures.