Graph-Based Post-Failure Reconfiguration
After irreversible damage the system does not attempt to recover the nominal configuration. It reconstructs the feasible stable-state space, evaluates admissible transitions, and searches for a safe path to the best mission-relevant state that remains reachable.
Stable states, not configuration labels
A graph node is admitted only when the corresponding configuration has a stable operating point under the current residual-resource vector. The post-failure search therefore happens over safely reachable stable states.
The plant dynamics depend on the physical state, control input, residual resources and selected configuration.
Each node combines configuration, stable operating point, resource context and mission-weighted utility.
Damage changes the feasible state space
The example removes actuator A2 permanently. V0 remains visible as historical context, but it is no longer a valid node in the post-damage feasible graph.
Graph before damage, graph after damage, selected path
Use the controls to inspect the nominal topology, prune it with the damaged resource vector, or animate the computed reconfiguration path. The diamond qf is a transient failure point and is intentionally excluded from the stable-state matrices.
Transitions shown as matrices
The same topology is exposed numerically. A(ρ) answers whether a direct stable-state transition is admissible. C(ρ) carries the normalized transition penalty used by the graph search.
| V0 | V1 | V2 | V3 | V4 | V5 | V6 | |
|---|---|---|---|---|---|---|---|
| V0 | 0 | 1 | 1 | 1 | 0 | 1 | 1 |
| V1 | 1 | 0 | 1 | 1 | 0 | 1 | 1 |
| V2 | 1 | 1 | 0 | 0 | 1 | 1 | 1 |
| V3 | 1 | 0 | 1 | 0 | 1 | 1 | 1 |
| V4 | 0 | 0 | 1 | 0 | 0 | 1 | 1 |
| V5 | 0 | 0 | 0 | 0 | 1 | 0 | 1 |
| V6 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| V0 | V1 | V2 | V3 | V4 | V5 | V6 | |
|---|---|---|---|---|---|---|---|
| V0 | 0 | 0.10 | 0.12 | 0.15 | ∞ | 0.08 | 0.05 |
| V1 | 0.20 | 0 | 0.17 | 0.25 | ∞ | 0.11 | 0.08 |
| V2 | 0.16 | 0.13 | 0 | ∞ | 0.19 | 0.10 | 0.07 |
| V3 | 0.20 | ∞ | 0.15 | 0 | 0.24 | 0.09 | 0.07 |
| V4 | ∞ | ∞ | 0.18 | ∞ | 0 | 0.08 | 0.07 |
| V5 | ∞ | ∞ | ∞ | ∞ | 0.17 | 0 | 0.05 |
| V6 | ∞ | ∞ | ∞ | ∞ | ∞ | ∞ | 0 |
Prototype weighting: transition time, energy demand, transient risk and additional degradation. All components are normalized before weighting.
Choose the best safely reachable terminal state
The capture state V1 is the search origin. Dijkstra supplies the minimum transition cost to each reachable stable state; mission utility then competes with path cost.
The prototype chooses the feasible state with maximum mission-weighted utility after accounting for transition burden.
| State | Feasible | Φ | Path C | J |
|---|---|---|---|---|
| V0 · Nominal | no | 0.96 | — | — |
| V1 · Capture | yes | 0.52 | 0.00 | 0.52 |
| V2 · Reduced BW | yes | 0.69 | 0.17 | 0.63 |
| V3 · Observer | yes | 0.61 | 0.25 | 0.52 |
| V4 · Mission | yes | 0.84 | 0.36 | 0.72 |
| V5 · Safe hold | yes | 0.39 | 0.11 | 0.35 |
| V6 · Shutdown | yes | 0.08 | 0.08 | 0.05 |
Transitions shown as transitions
The global graph explains the space; the trace explains the actual recovery route. A forbidden direct jump is not hidden — the route must pass through stable intermediate states.
Graph theory inside a supervisory control process
The graph planner is only one subsystem. UML views make explicit when the resource estimator, graph builder, planner and supervisor exchange authority and evidence.
The target is not the nominal configuration. It is the best safely reachable stable state.
EXP-02 makes the distinction explicit: damage changes the graph itself. Reconfiguration therefore requires topology reconstruction, matrix-level admissibility evidence, graph search, and transient verification before a degraded mission state can be accepted.