Research on the evaluation method of pilot workload in EVTOL aircraft operation

In the study of pilot control strategies for manned eVTOL aircraft, it is essential to delve into the workload imposed by pilot control. Such an inquiry can facilitate the identification of more rational and efficacious control strategies, thereby alleviating the strain on pilots. So far, the Cooper-Harper rating (HQR, Handling Quality Rating) is still the main standard for analyzing pilot control workload. However, this subjective evaluation often makes it difficult to determine the main factors and their impact accurately and quantitatively on the control workload. This paper introduces an assessment technique for the workload of pilot control, utilizing wavelet transformation to account for the correlation between the intensity of pilot control, its frequency constituents, and the associated level of control challenge. Initially, the paper offers a concise overview of the methodologies for analyzing control actions, encompassing both temporal and spectral perspectives. Then, we evaluate the pilot control workload using actual pilot control inputs and HQR ratings from a helicopter flight test. The results indicate that the wavelet analysis based on time-frequency representation can identify the frequency components and energy levels of pilot control actions at different time points. Furthermore, a correlation is identified between the amplitude of pilot control inputs, their frequency components, and the HQR ratings.