A feasibility analysis for the development of novel aircraft weight and balance monitoring systems based on fiber BRAGG grating sensors technology

This paper deals with a feasibility study of a new conception aircraft weight and balance (W&B) measurement system to be installed on aircraft landing gears, totally based on Fiber Bragg Grating (FBG) sensor technology. The basic idea relies on the determination of the instantaneous values of the weight and centre of gravity (CoG) coordinates of an aircraft by measuring, through the suitable combination of strain data provided by a FBG sensors network, the loads applied to the main/nose landing gears. To validate this system at the preliminary stage, we have designed and developed a lab mock-up demonstrator consisting of a metal plate (mimicking the aircraft body) supported by 3 PVC cylinders (simulating the landing gears), each one integrated with a FBG strain sensor. An extensive experimental analysis has been carried out by applying known weights to the plate placed at given coordinates, and then retrieving every value of weight and CoG from the strain data provided by the FBGs, once temperature effects are eliminated. Results obtained are in good agreement with those calculated with a suitably developed mathematical model, and demonstrate the capability of the proposed W&B architecture to determine the weight applied to the Lab mock-up with an accuracy <2%,as well as the CoG coordinates with millimetric precision.