A smooth control allocation method for a distributed electric propulsion VTOL aircraft test platform

Abstract

Distributed electronic propulsion (DEP) aircraft with vertical take-off and landing (VTOL) ability mostly equipped with multiple redundant tiltable propulsors, which are used to provide not only thrusts, but also control torque in all flight mode. The features make the control allocation problem of these aircraft both complex and important. Therefore, this paper proposes: (і) a prototype platform for DEP VTOL aircraft that allows researchers to design and analyse control allocation strategies, and (іі) a uniform hierarchical control allocation method that can be adapted to both MC and FW modes. The platform contains ten fully actuated thrusters, which are distributed in the scaled geometry of a typical DEP-VTOL aircraft. The proposed control allocation strategy uses hierarchical structure to avoid high-dimensional matrix operations for the redundant actuators. The additional constraints on the thrust and tilt angles of the actuators are addressed by adopting cascade generalized inversion (CGI) to force decompensation (FD)-based methods by a coordinate transformation. A novel smooth strategy through Schur Complement is also presented to achieve steady and smooth transition from MC to FW mode. Finally, the proposed method is implemented in the authors' novel platform in both simulations and flight experiments to demonstrate its effectiveness and smoothness.

Optimal decision for the satellite navigation system under navigation countermeasures based on spoofing effect evaluation results

“…Based on Figure 1, according to the characteristics of three testing methods (full digital simulation method, hardware‐ in‐the‐loop simulation method, and full physical testing method) [34], the definitions, mathematical models, and testing steps of common indices are created to evaluate the GNSS spoofing effect as the basis for building the benefit matrix.…”

Improved PVTOL Test Bench for the Study of Over-Actuated Tilt-Rotor Propulsion Systems

“…For example, in [14], the control allocation for a spacecraft using two kinds of actuators was solved by a proportional distribution of the desired control torque considering the characteristics of each actuator. Physical insight has also been used to refine Cascade-Generalized Inversion (CGI) approaches, such as in [15], where a test bench for a vehicle with multiple tilting rotors was controlled by grouping several physical actuators in a hierarchical manner. There are also several mathematical tools which can aid in solving the allocation problem, such as the Moore-Penrose pseudoinverse matrix and the Karush-Kuhn-Tucker (KKT) optimality conditions [16].…”