Investigations on boundary avoidance tracking and pilot inceptor workload

Abstract

Handling qualities research largely depends on the understanding of the pilot's behaviour in the control loop. Conventional pilot models are based on the idea that the pilot tries to achieve target conditions, e.g. a specific attitude. In 2004, Gray introduced the so-called boundary avoidance tracking theory which considers the pilot as someone who tracks away from threatening conditions (boundaries) when they become dominant. In the frame of a preliminary simulator study with five test subjects, the flight test technique which is associated with boundary avoidance tracking was performed and the concept was investigated in detail. Especially, the presumption was considered that this new technique can raise the pilot gains in a buildup fashion and can, therefore, be more effective than conventional techniques. Gray's pilot inceptor workload criterion, a new pilot gain measure, was enhanced and used to explain these specific effects. AbbreviationsBAT Boundary avoidance tracking FPM Flight path marker FTT Flight test technique HQDT Handling qualities during tracking PIO Pilot induced oscillation PIW Pilot inceptor workload RMS Root mean square TTB Time to boundary

Estimating pilots’ cognitive load from ocular parameters through simulation and in-flight studies

“…The experimental piloting task was designed to effect fine variation in cognitive load, instead of gross variation. The pilot pitch tracking task was superimposed with constantly closing boundary to bring in gradual increase in cognitive load in fine steps (Niewind, 2011). In the following subsections, we have described our study in detail.…”

“…Gray (2005) hypothesized that the boundary avoidance tracking theory which considers the pilot tracks the boundaries imposed in flying when they become dominant in terms of threatening conditions. In the frame of a preliminary simulator study with five participants, the flight test technique which is associated with boundary avoidance tracking was performed by Niewind (2011), and the concept was investigated in detail (Blake, 2009). Niewind's study confirmed that the new technique can systematically and gradually raise the pilot gains in a buildup fashion.…”

“…To analyze the fine variation in cognitive load we analyzed the variations in number of saccades and fixations between each boundary size to observe the effect caused by boundaries on cognitive load (Niewind, 2011). We analyzed the correlation of number of saccades and fixations with pilots' control inceptor movement and tracking error in further details.…”

“…• Duty Cycle is a measure of Pilot Inceptor Workload (PIW) and is measured by the percentage of time with significant stick movement (Niewind, 2011).…”

“…• Aggressiveness is another measure of pilot inceptor workload and measured by the RMS value in deg/sec of the speed with which the stick is moved (Niewind, 2011).…”