MATHEMATICAL AND HYBRID DYNAMIC MODELING FOR SLED CRASH TESTING ON AIRCRAFT SEATS

摘要

Occupant lumbar load under CFR Part 23 and 25 is being obtained by using different methodologies including hybrid dynamic modeling and MADYMO analysis. The output of these methods is validated with full scale sled tests results. A crashworthy structure is designed such that in the event of crash, it absorbs impact energy in a controlled manner. The main subsystems of an aircraft involved in crashworthiness are seat cushion, which is part of seat structure, restraints, fuselage and landing gear. Polyurethane foams are being used as acoustic purposes, as padding in the finished interior panels of the aircraft, and seat cushions. Their main application is mostly in seating purposes to provide comfort for occupant. All the seat cushions have to pass Federal Aviation Administration (FAA) Regulations before being installed on the seats. These regulations require a dynamic sled test of the entire seat system for certifying the seat cushions. This traditional dynamic testing is also required for replacing the deteriorated cushions with new buildup cushions which is time consuming and costly. This research provides methodologies based on simulation and modeling to eliminate, or at least, minimize the number of full scale dynamic sled tests defined by regulations for aircraft seats.