Evaluating Stick Stiffness and Position Guidance for Feedback on Flight Envelope Protection

Abstract

Contrary to this, however, it was found that haptic feedback mainly contributed to pilot learning, and performance persisted after haptic support was removed. In addition, haptic support did not improve performance during the first run, which indicates that when implemented on an aircraft, it might not provide pilots with support the very first time they encounter a new situation. As the haptic feedback system aimed to support pilots also in new, unforeseen circumstances, a new iteration of the haptic feedback is required.Actively supporting the pilot has been found to help at the first encounter, yet is subject to reversion to base performance when the support is removed. In a skill acquisition task where a slider had to be moved left and right, four groups of participants received feedback on their performance in a training phase at different times: after each run, or an average score after every five, ten or fifteen runs. [9] Their results showed that increasing the amount of feedback increases performance. Immediately after the training phase, another set of measurements was performed where no feedback was provided. There, the group with the most amount of feedback in the training performed worst, although not significantly different from the other groups. Another measurement was performed two days after the initial training, which showed again a tendency for decreasing performance with increasing feedback during training. This phenomenon is called the "guidance hypothesis": a dependency on the feedback develops while learning the task; disabling this feedback then results in worse performance, due to required re-adaption. This phenomenon was also reported in a similar, vertical task. [10] Within the field of haptic feedback, different applications have been recently designed to support the human operator in a task, and to provide support from the first encounter. Examples of this are a support for an abstract control task ([11]), a lane keeping assist in the automotive domain ([12, 13]), and an obstacle-avoidance system for UAV tele-operation. [14] These examples used active haptic feedback, for example an increased stiffness or actively moving control device, to guide the operator to complete the task. Transferring these active haptic feedback principles to the aircraft flight envelope protection system might provide a feedback system which supports pilots from the first run and solve the issue with our previous 'cueing' system. [8] Nevertheless, such implementations of haptic support have been found to be also hindered by to the guidance hypothesis described before, and it should be investigated whether this is also true in our particular application.The aim of this paper is to present a new haptic feedback for FEP design which is more actively 'guiding' the pilot, and to compare the results of this guidance haptic feedback system, as well as the existing 'cueing' haptic feedback system, to the results of a group of pilots who did not receive any haptic feedback at all. It is hypothesised that the group wi...