Haptic Assistance For Helicopter Control Based On Pilot Intent Estimation

Haptic support systems have been widely used for supporting human operators when performing a manual control task. These systems are commonly designed to track known target trajectories. However, the trajectory to track is not known in many realistic cases. For instance, the pilot-intended trajectory is not known beforehand when considering a helicopter pilot flying in free-flight. This paper proposes a possible approach to design a haptic shared control system when the target trajectory is not known a priori. Especially, the aim of the proposed design is to help minimally trained pilots during a 2-degree-of-freedom lateral/longitudinal helicopter free-flight task. To accomplish this goal, first, a Pilot Intent Estimator (PIE) is developed to infer pilot intent. Then, the corresponding intended trajectory is generated. Finally, a haptic feedback is designed to track the estimated intended trajectory. The designed PIE was evaluated in a preliminary test with an experienced helicopter pilot. Then, a human-in-the-loop experiment with minimally trained participants was conducted to assess the proposed shared control system. Results showed the effectiveness of the PIE to estimate the correct direction of motion chosen by the pilot. Furthermore, the haptic feedback helped participants to accomplish the control task with better task performance (i.e., lower tracking errors and lower amount of control activity) compared with manual control.