Study on the evaluation method of pilot workload in eVTOL aircraft operation

This paper investigates the pilot control strategy and workload associated with the manned electric Vertical Take-Off and Landing (eVTOL) aircraft. This research aims to identify control strategies that are both rational and effective in reducing the pilot's workload. Although the Cooper-Harper rating (HQR, Handling Quality Rating) remains the prevalent benchmark for assessing pilot workload, its subjective nature often complicates the precise quantitative identification of the key factors influencing workload. This study introduces an assessment method for pilot control workload using wavelet transform to evaluate pilot workload, focusing on the correlation between pilot control magnitude, frequency components, and complexity. We begin with a review of control action analysis methods in both time and frequency domains. Subsequently, by selecting an appropriate wavelet function and a sampling frequency, we develop the assessment method for pilot control strategy and workload based on wavelet analysis. Finally, we assess pilot workload using real pilot inputs with HQRs obtained from helicopter flight tests and tilt-rotor aircraft conversion simulations. The results indicate that this approach is capable of precisely pinpointing the frequency components and energy levels within pilot control actions throughout different time periods. Furthermore, a significant correlation is observed between pilot control characteristics, frequency components, and HQRs. Consequently, the developed approach provides a rational framework for quantifying and analyzing pilot workload in a range of eVTOL aircraft scenarios.