Too often, we underestimate the importance of balance. And yet, if a detail disturbs it, we can suffer a fall or… dizziness! Human beings have involuntarily discovered the drawbacks of motion sickness –motion sickness– as their means of movement increased.
It is estimated that 25-30% of the population is regularly affected due to this phenomenon, a figure that may be underestimated, since little is known: it is often summarized in symptoms of discomfort (nausea, sweating, paleness, hypothermia, headaches, vomiting), although it can also manifest itself in milder forms such as drowsiness, apathy or decreased cognitive ability. 60-70% of travelers experience it at least once in their lives.
Is more common in cars. Passengers are more sensitive than drivers Due to the lack of anticipation of trajectories. The conflicts between the information provided by the different senses disturb our balance and the difficulties in adjusting our posture to adapt ourselves are the two main theories to explain it.
One would think that, in the more than a century since the development of the automobile, this problem would be solved. But it has not been that way. And as the automotive industry undergoes a technological metamorphosis, changes such as electrification, digitization, and vehicle automation are bringing benefits as well as new challenges.
Some of these advances run the risk of creating or accentuating this famous imbalance and further limiting users’ ability to anticipate. Consequently, they increase the risk of experiencing discomfort symptoms more frequently. Here are those whose effects have already been documented.
Electrification: fewer signals and more abrupt movements
The engine of an electric car is more linear and quieter than a combustion engine. This advantage has a drawback: it can hinder users’ ability to assimilate the movement of the vehicle. For example, for those used to estimating acceleration by the sound of the engine, they lose that clue with the silence of an electric motor.
Similarly, the vibrations of the combustion engine sometimes are perceived as calming. Resting your head against the vibrating window is indeed beneficial for some passengers. These same vibrations are almost completely eliminated in an electric car.
The adoption of regenerative braking (to regain electric range during deceleration) can also be disruptive. The decelerations induced by this system, generally low frequency and sometimes abrupt, can be particularly destabilizing. Conversely, jerks on the throttle can induce jerkiness due to the high torque of these engines.
Interiors that favor distraction
Another risky technological advance is the presence of increasingly large and numerous screens inside vehicles. Beyond their appeal to the user, these screens “overload” you with visual information.
Its omnipresence favors distraction, also at the risk of creating a conflict between visual information and inertial information of movement that the body receives. By concentrating on the content of the screens, the passenger limits his ability to assimilate the visual signals that allow him to correctly perceive his position and speed in space, that is, the exterior view of the vehicle. That is why it is not advisable to concentrate on a book or a screen during a hectic trip…
This trend is likely to increase in the coming years, with vehicles that could even have screens in the windows or offer virtual reality integration. All of them are invasive elements for passengers, which can affect their well-being.
Knowing that one is more prone to nausea when trapped in a space overloaded with screens can indeed stress vulnerable passengers. It is not a trivial question if one takes into account that psychological state greatly influences motion sickness: Up to 40% of the severity of symptoms can be attributed to it.
Autonomous driving and lack of foresight
Autonomous cars may also have repercussions.
At present, vehicles are only equipped with a partial level of automation, but in the future they will be able to drive themselves. This means that the task of driving, which is the best way to anticipate trajectories and limit symptoms, will disappear in the long run.
For those who have always driven, the situation can be complicated. Since our susceptibility to motion sickness depends in part on our habit of being passengersregular drivers can be susceptible to motion sickness to the point of not being able to travel in highly autonomous vehicles.
Also, with the disappearance of the driver’s seat, the cabins will be redesigned to be more welcoming, like lounges on wheels. These new configurations will offer more freedom to passengers, who will be able, for example, to turn their seats to face the road to chat with other occupants. However, it is believed that sitting with your back to the road increases the risk of discomfort. Although experiments have shown that it doesn’t make any differencethis idea it may be a psychological bias that facilitates the appearance of symptoms.
One of the promises of the autonomous vehicle is to allow its passengers to use their travel time in leisure or productivity activities. But, as we have seen, the use of screens favors dizziness. The popularization of taxi and VTC trips, in which users have their eyes glued to their tablets and other mobiles, has already confirmed this trend.
Finally, it should be noted that in non-autonomous vehicles, the incidence of motion sickness is still moderate, since drivers can adapt their driving style if their passengers show discomfort. However, this human dimension will disappear in autonomous vehicles, whose driving style will be less flexible and less natural than that of a human driver.
The stress or lack of confidence associated with this driving style could once again become an aggravating factor.
The human being, the main obstacle to technological advances?
The multiple factors mentioned could, therefore, penalize the appearance of the “vehicle of the future”, autonomous and electric, initially intended to increase mobility and be accessible to the greatest number of users.
In the absence of effective means to counteract it, it is possible that a increase in cases of motion sickness in these vehicles causes their rejection. Taking into account the ethical, psychological and legal dimensions of their development, the human factor is therefore the main obstacle to the introduction of these new types of vehicles.
For several years, there has been a growing interest from car manufacturers and suppliers for better understanding this phenomenon and ultimately reducing it effectively. Not for reasons of public interest, but because it would compromise the adoption of these new technologies.
To date, the causes and triggering mechanisms of motion sickness remain unclear, so industry research is focused on how to limit its occurrence. Various avenues are being explored. Among them, the use of signs visuals, audible and tactile to help the user to better perceive and anticipate the movements of the vehicle, and the programming of a comfortable and human-like driving style that limits sudden accelerations.
William EmmondDoctorant sur le thème de la réduction du mal des transports en voiture, Belfort-Montbéliard University of Technology
This article was originally published on The Conversation. read the original.
