Hardware in the loop laboratory simulation to test a distributed avionic system

After some years of development, a new fuel management distributed system has been proposed by a European Research Project. The system is based on new smart components connected via a fieldbus. All components have the same microcontroller with the same control code. The smart components are valves, pumps, and sensors. A laboratory physical simulator has been implemented, to support the development of the control code. The simulator includes scaled tanks and pipes, and smart components. Fuel management functions can be reproduced, and the fieldbus behavior can be monitored. In parallel, a computer simulation has been developed, using two interconnected computers. One of the computers simulates the physical plant: fuel, tanks, valves, pumps, etc. The other computer simulates in realtime the microcontroller network. Both computers are connected via analog signals, the same signals as in the laboratory physical simulator. Now computers and physical simulator can be mixed, by switching the origin of signals, form computer or from physical plant. In this way, malfunctions and problems can be studied with non destructive tests. The paper describes the research context, and focus on the development and functionality of the hardware in the loop simulation.