Smooth Reference Command Generation and Control for Transition Flight of VTOL Aircraft Using Time-Varying Optimization

TL;DR

This paper introduces a novel time-varying optimization approach for generating smooth reference commands during VTOL aircraft transition flights, addressing abrupt transitions caused by traditional offline methods.

Contribution

It proposes a prediction-correction interior-point framework that solves an ODE for real-time, smooth command generation, improving transition control in VTOL aircraft.

Findings

Successfully generates smooth reference commands in simulations

Demonstrates real-time applicability of the method

Enhances transition flight control for VTOL aircraft

Abstract

Vertical take-off and landing (VTOL) aircraft pose a challenge in generating reference commands during transition flight. While sparsity between hover and cruise flight modes can be promoted for effective transitions by formulating $\ell_{1}$-norm minimization problems, solving these problems offline pointwise in time can lead to non-smooth reference commands, resulting in abrupt transitions. This study addresses this limitation by proposing a time-varying optimization method that explicitly considers time dependence. By leveraging a prediction-correction interior-point time-varying optimization framework, the proposed method solves an ordinary differential equation to update reference commands continuously over time, enabling smooth reference command generation in real time. Numerical simulations with a two-dimensional Lift+Cruise vehicle validate the effectiveness of the proposed method, demonstrating its ability to generate smooth reference commands online.