Mitigation Of Motion Sickness In Rotorcraft By Using H?-Control

Abstract

Motion sickness is a medical condition that presents with symptoms including nausea, disorientation, and vomiting. The condition is triggered by motion frequencies below 0.5 Hz, which affect the sensory organs of the passengers. The symptoms manifest over several minutes to hours and decrease when the motion exposure is terminated. In rotorcraft, low-amplitude, broadband rigid-body vibrations, caused by atmospheric disturbances, are the primary source of motion sickness. These vibrations are a reflexive response of the automatic flight control system and the pilot to atmospheric disturbances. A negative impression of the helicopter ride quality is likely to result if motion sickness is provoked during the flight. It is therefore beneficial to reduce the magnitude of the motions contributing to motion sickness. This can be achieved primarily through the disturbance rejection properties of the flight control system. Therefore, a systematic design procedure within the H? control framework is applied to shape the disturbance rejection properties of the flight control system, thus reducing the severity of motion sickness while complying with relevant requirements such as stability and handling qualities. The simulation results indicate a good performance of the H?-controller in reducing motion sickness while achieving level 1 handling qualities. Consequently, the proposed systematic design procedure is a promising approach to improve the ride comfort in rotorcraft.