Design and implementation of a hardware-in-the-loop simulation system for small-scale UAV helicopters

We present in the paper the design of a hardware-in-the-loop simulation framework and its actual implementation on our custom constructed unmanned-aerial-vehicle (UAV) helicopter systems. Real-time hardware-in-the-loop simulation is one of the most effective methods for the verification of the overall control performance and safety of the UAVs before conducting actual flight tests. In our proposed framework, four modules, which include onboard hardware, flight control, ground station and software, are integrated together to realize the hardware-in-the-loop simulation. This design is successfully utilized for simulating several flight tests including basic flight motions, full-envelope flight and multiple UAV formation flight. Results obtained show that the constructed hardware-in-the-loop simulation system is highly effective and useful.