Real-Time Nonlinear Model Predictive Control of Large Multirotor Aircraft

This brief introduces a nonlinear model predictive control (NMPC) scheme for multirotor electric Vertical Take-off and Landing (eVTOL) aircrafts with many actuators. We present a novel modeling approach using real-time iteration (RTI), which directly incorporates constraints on numerous actuators, effectively handling common control allocation issues within the model predictive control (MPC) formulation. This approach in particular accounts for the slower actuation system dynamics inherent to large-scale multirotors while satisfying real-time embedded computational constraints. Hardware-in-the-loop (HIL) tests on a Jetson TX2 confirm up to ~70% faster solve times at <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$N=32$</tex-math> </inline-formula> while maintaining the flight stability.