INDI Control Law Structure for a MEDEVAC eVTOL and Its Reference Models: Feedforward, Physical Limitations, and Innerloop Dynamics for Optimal Tracking

This paper presents the implementation of an Incremental Nonlinear Dynamic Inversion (INDI) control law structure for a Medical Evacuation (MEDEVAC) electric Vertical Take-Off and Landing (eVTOL) aircraft, focusing on its reference models, feedforward strategies, physical limitations, and innerloop dynamics for optimal tracking. The INDI approach addresses the limitations of Nonlinear Dynamic Inversion (NDI) by utilizing measurement-based adjustments to enhance robustness in control performance. The proposed reference model structure, including feedforward mechanisms, is designed to handle the physical limitations and dynamic requirements of the eVTOL. Detailed flight test insights and results are provided, demonstrating the efficacy of the INDI control law and reference model in ensuring stability, accurate tracking, and overall performance under various operational conditions. These findings offer valuable information for the future development of reliable and efficient control systems for advanced aerial mobility solutions.