Hardware-in-the-loop test for fault diagnosis system of tilt rotor UAV

The tilt rotor UAV developed in KARI has fault diagnosis functions to enhance system reliability, which were implemented using the operational flight program (OFP) of the flight control computer (FCC). Basically, they conduct built-in-test (BIT) between the FCC and onboard systems such as the communication system, navigation system, and actuators, etc. If a system has no BIT function, fault diagnosis can be performed by checking if the corresponding physical data exit within the available range. In order to test each function, a test device for fault diagnosis was developed and used for hardware-in-the-loop simulation (HILS). The test apparatus consists of the operation control computer (OCC) and the verification computer (VC), which can be interfaced with the simulation computer via Ethernet. The OCC creates faults into the VC and displays the result of fault diagnosis. The VC has simulation models for each onboard system and provides output information to FCC. The FCC performs fault diagnosis and returns the result of fault diagnosis. This paper describes the fault diagnosis functions of the tilt rotor UAV, the test environment used to evaluate them and the test result in hardware-in-the-loop simulation environment.