An Active Suspension System for Mitigating Motion Sickness and Enabling Reading in a Car.

INTRODUCTION: The advent of autonomous automobiles raises new challenges for maintaining passenger safety and comfort. The challenge addressed here is how to predict and mitigate motion sickness when passengers read in a moving vehicle. METHODS: We utilized a car equipped with a commercial active suspension system developed for attenuating the transmission of road surface fluctuations to passengers. The system was used to reproduce, in a parked car, either the vibrations that would be experienced in a moving car equipped with a conventional suspension system (unmitigated ride) or the attenuated vibrations that would occur on the road with the active cancellation system engaged (mitigated ride). We evaluated the consequences of these two simulated ride conditions for reading performance, comfort, and evocation of motion sickness. RESULTS: Both ride conditions reduced the 0 to 0.8 Hz vibrations to below threshold for evoking motion sickness during passive exposure [corrected]. Only the mitigated ride condition attenuated frequencies in the 0.8 to 8 Hz band where visual suppression of the vestibulo-ocular reflex is known to break down, and this condition also reduced the motion sickness induced by reading and increased reading comprehension and comfort relative to the unmitigated ride. DISCUSSION: The palliative effects of 0.8 to 8 Hz attenuation are discussed in terms of the different mechanisms underlying motion sickness evoked by reading in a vehicle versus mere exposure to vehicle motion without reading. Implications for ISO-2631 standards for human exposure to vibration are also discussed.DiZio P, Ekchian J, Kaplan J, Ventura J, Graves W, Giovanardi M, Anderson Z, Lackner JR. An active suspension system for mitigating motion sickness and enabling reading in a car. Aerosp Med Hum Perform. 2018; 89(9):822-829.

The influence of sleep deprivation and oscillating motion on sleepiness, motion sickness, and cognitive and motor performance.

Our goal was to determine how sleep deprivation, nauseogenic motion, and a combination of motion and sleep deprivation affect cognitive vigilance, visual-spatial perception, motor learning and retention, and balance. We exposed four groups of subjects to different combinations of normal 8h sleep or 4h sleep for two nights combined with testing under stationary conditions or during 0.28Hz horizontal linear oscillation. On the two days following controlled sleep, all subjects underwent four test sessions per day that included evaluations of fatigue, motion sickness, vigilance, perceptual discrimination, perceptual learning, motor performance and learning, and balance. Sleep loss and exposure to linear oscillation had additive or multiplicative relationships to sleepiness, motion sickness severity, decreases in vigilance and in perceptual discrimination and learning. Sleep loss also decelerated the rate of adaptation to motion sickness over repeated sessions. Sleep loss degraded the capacity to compensate for novel robotically induced perturbations of reaching movements but did not adversely affect adaptive recovery of accurate reaching. Overall, tasks requiring substantial attention to cognitive and motor demands were degraded more than tasks that were more automatic. Our findings indicate that predicting performance needs to take into account in addition to sleep loss, the attentional demands and novelty of tasks, the motion environment in which individuals will be performing and their prior susceptibility to motion sickness during exposure to provocative motion stimulation.