A vehicle is provided that has a rigid dressing raft 200. The rigid dressing raft 200 provides a part of a fluid and/or electrical system to the vehicle. The rigid dressing raft comprises elongate fibers 232, which may provide strength to the raft. The fibers 232 are electrically conductive, and a voltage source may be applied to at least one of the fibers. The fiber 232 may form a part of an electrical measurement circuit 400, such as a wheatstone bridge, which may be used to determine the electrical resistance of the fiber 232. The electrical resistance of the fiber 232 may then be used to determine the temperature and/or stress/strain of the raft 200.