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Bioengineering

Warnings against drowsiness

Designed to prevent accidents, special seat vibrates, ventilates, and warns drivers when they are tired

Photo: Miguel Boyayan | Illustration: Alexandre AffonsoDrowsiness, fatigue, and distraction at the wheel—in addition to drunkenness and excessive speed—are among the leading causes of traffic accidents that kill about 42,000 people in Brazil every year, according to the Mortality Data System (SIM) coordinated by the Ministry of Health. This is a global phenomenon, according to the World Health Organization (WHO), which recorded 1.2 million fatalities every year due to traffic accidents. In its Global Report on Road Safety 2015, the WHO, citing data from SIM for Brazil, observes that among total automobile accident deaths, 5% were automobile drivers, 18% were passengers in those vehicles, 1% were bus passengers and drivers, 2% were truck passengers and drivers, 28% were motorcyclists, 20% were pedestrians, and 23% were not specified in the reported data.

Given the magnitude of the problem, technologies that could somehow reduce these numbers are always welcome. Two such technologies are now being developed in Brazil to try to at least curb the accidents that occur among drivers of trucks and buses and are caused by drowsiness, fatigue, or distraction. The first is an anti-sleep seat designed by the companies Marcopolo, TWE, and the Multidisciplinary Centre for Sleepiness and Accidents (CEMSA) that are trying to reduce the fatigue experienced by professional drivers and prevent them from falling asleep while driving. The other device is from Vale and known as the Brain Computer Interface (BCI). It is able to capture electrical waves from the brain and use them to anticipate actions that a truck driver at its mines would take during the normal course of activities at the company and in the future, while operating heavy vehicles that travel the highways. The device could even handle actions by a locomotive engineer—braking, for example—and perform them even before the driver takes the initiative.

The driver’s seat developed by Marcopolo, a manufacturer of bus bodies, has been dubbed the Antisleep Seat and was designed by the company at its Innovation Center (MIC) situated in Caxias do Sul, Rio Grande do Sul State. Marcopolo worked with CEMSA in Belo Horizonte and TWE, a company that is part of the Canadian group Woodbridge, manufacturer of the molded foam used to cushion the seats. CEMSA was founded by Marco Tulio de Mello, an expert in sleep disturbances and who designed the seat. “This is a research company and our objective is to support companies in managing the fatigue risk experienced by their employees.”

Photo: Eduardo Cesar | Illustration: Alexandre AffonsoThe seat is equipped with four devices—a vibrating seat bottom, a thermal heating blanket, a cooling function, and speakers to convey messages. These function during times of driver fatigue and drowsiness in order to keep drivers alert. The seat commands are activated by a cellular application developed by CEMSA that communicates via Bluetooth.

The application comes in three versions. These are not complementary stages; each has different specifications and all are intended to determine a driver’s baseline fatigue before he begins his workday. In the first version, the workers themselves feed the program with personal data such as age, weight, marital status, number of children, daily transportation routine, and how they sleep. Drivers also report the times they begin and end their shifts and how many hours of sleep they had in the preceding 48 hours. “The second version conducts a test of attention and concentration, using something similar to a cellphone game,” Mello explains.

The third version uses a piece of equipment known as a strength platform that looks like a scale, which the driver has to stand on. “It detects balance, and that data can tell us how tired the person is,” says Mello. These assessments and tests furnish the data points that serve as parameters for comparisons with the driver’s state over the course of the workday and should therefore be done soon after the driver awakens from a good night of sleep and shortly before beginning a trip. “By comparing the results, an algorithm (set of mathematical instructions), also developed at CEMSA, calculates the professional’s level of fatigue at the start of a trip and anticipates when would begin to be tired, activating the alert devices at different levels and times, depending on the severity of the fatigue,” explains Eduardo Kakuichi, an innovation analyst at the Marcopolo Innovation and Competitive Intelligence Division. “The seat was initially designed to be used by bus drivers, but in the future we will be able make it available for use in trucks, farm machines, trains, and aircraft.

Vale Simulator used by Vale in Vitória (ES) to capture electrical brain waves during tests of train engineersVale

To make these calculations and determine the level of fatigue, the application also considers the circadian cycle, the 24-hour period on which the biological rhythm of almost all living beings is based. “The internal temperature of the human body does not vary within a time frame that runs from 6:00 a.m. to 9:00 p.m., with a slight drop after midday,” Kakuichi says. “After 9:00 p.m., body temperature falls until it reaches the minimum at about 4:00 or 5:00 a.m.”

The application determines the time at which the seat should vibrate or warm the driver’s back using the thermal blanket. “The actions of the seat alter the temperature of the surface of the body and thus its internal temperature, delaying the start of the fatigue phase,” Kakuichi explains. “At another point, the ventilators installed in the seat will blow air on the driver’s neck and calves, lowering local peripheral temperature, causing a mild thermal shock that leaves the driver more alert. In addition, the driver receives audio messages through built-in speakers, which serve to break the monotony and re-establish attentiveness.”

Among the available messages are warnings about the pending onset of fatigue: “You have already been working or awake for some time—at your next stop, stay near a bright light.” In more critical conditions, the following message would be broadcast: “Attention, attention, attention! Your fatigue has reached an extreme level. It is urgent that you end your workday or stop to rest. Please don’t take risks, be smart, be careful.”

Before the driver can act
The BCI device produced by the Vale Technological Institute (ITV) in Belém, Pará State, works through an interaction between brain and computer. Using electrodes attached to the head, the device captures electroencephalographic signals—electrical brain waves—during the performance of a task. To test the BCI, those waves were captured from the brain of an engineer while he “drove” a train using a simulator located in Vale’s Logistical Engineering Center in Vitória, Espírito Santo State. What the developers of the device were interested in were the electroencephalographic signals recorded immediately before, during, and after certain actions—such as vehicle braking, acceleration, and deceleration—were taken by the driver.

Project coordinator Shubert Carvalho, a computer scientist and researcher at the ITV, explains that this w

Volvo LED bulbs on the dashboard shine invisible infrared light on the driver’s face. Sensors capture the reflected light and identify signs of drowsiness and fatigueVolvo

as done several times with different engineers operating the simulator to create a database of the signals captured from their brains as they performed certain actions. Carvalho explains that those signals are continuous and that in order to be used by the BCI, they need to be divided into parts. “Technically, those pieces are known as epochs,” he explains. “Each has a fixed size, a frequency band, and a temporal relationship with an action. The zero point is where the action, such as braking, occurred. The negative time refers to what precedes its execution and the positive time refers to what comes afterward.”

The BCI is programmed to recognize those patterns of electrical and frequency signals and associate them with an action that the driver of the vehicle would take. In tests conducted on the simulators at the logistical center, the anticipation by the BCI device occurred within one second, with 90% accuracy. In an actual situation, this would mean that the vehicle would be braked several meters earlier than a human driver would do so, thus preventing the accident or reducing the resulting damage.

Of the two technologies, the Marcopolo Antisleep Seat is closest to being put into use. “The Antisleep Seat is being field tested now, installed in buses owned by partner companies and monitored to evaluate potential improvements,” says Kakuichi. “We are working to make industrial-scale production viable, identifying the partners who will supply the components. The expectation is that it will be available for sale sometime in 2017.”

Vale’s BCI is still in the laboratory testing and prototype production phase. No date has been set for product launch. “This is a new technology, one that is not yet on sale anywhere in the world,” says Carvalho. The hardware will be manufactured by another company, yet to be determined. The device will be shaped like a tiara and weigh between 50 to 60 grams. “It will be comfortable and should not bother someone those who wear glasses, for example,” says Carvalho. “This, plus the fact that it is lightweight, is why drivers will be able to use it for several hours, day or night.”

Smart sensors and tests
There are other technologies available on the world market that are intended to prevent drivers of all kinds of vehicles from falling asleep at the wheel and so may reduce the number of accidents. One of them, called Driver State Estimation, is being developed by Volvo. It uses small LED bulbs that shine infrared light (invisible to humans) on the face of the driver. Sensors installed on the dashboard capture the reflected light and, according to certain data—such as how wide the eyes are open or the position and inclination of the head—“perceive” whether the driver is drowsy or has fallen asleep and send audio signals to warn him.

There are some U.S. systems that instead of acting on the driver, work on the car. This is the case of the so-called Safety Pilot being developed at the University of Michigan. Using a wireless network, the system enables automotive vehicles to communicate with each other in real time, thereby preventing collisions and improving traffic flow. In Detroit, General Motors is testing a prototype windshield that gives the driver an enhanced view of certain reference points along the road. Baptized the Advanced Vision System, it uses infrared cameras to monitor the position of the driver’s head and the direction in which he is looking at the road. The system can also highlight the sides of the roads when the driver is driving in fog, for example.

In addition to employing new technologies, another way to attempt to reduce the number of traffic accidents and fatalities is by assessing drug use by drivers. In March 2016, Law No. 13.103 of 2015 took effect in Brazil. It requires professional drivers of vans, trucks, and buses to undergo toxicological testing whenever they renew their driver’s licenses, change the category of vehicle they are allowed to drive, or are hired by or sever their ties to a company. Based on a sample from hair or nails, the exam can detect whether drugs such as cocaine, crack, heroine, marijuana and amphetamines were used within 90 days prior to the test. The law is enforced by the traffic departments in each state when drivers update their documents.

“Consumption of alcohol and other psychoactive substances is increasingly common among those professionals,” says psychologist Lúcio Garcia de Oliveira from the Department of Forensic Medicine, Medical Ethics, and Social and Occupational Medicine of the University of São Paulo School of Medicine (FM-USP). In February 2017, he completed a study on the effects of the use of multiple drugs on truck driver drowsiness in the state of São Paulo.

During the research study, which began in 2012, Oliveira talked to 684 drivers. “We found that during the 30 days prior to the interview, 67.3% of the participants had used alcohol–34.6% of them doing so heavily. Some 26% indulged in binge drinking, and 9.2% were at risk of developing dependency,” Oliveira reports. “Furthermore, 54.6% of them reported having used alcohol in combination with other drugs. Consumption was heavier among that population, characterized by the addition of five servings in comparison with those who ingested only one serving.”

Project
Study on polydrug use, cognitive, mental, and emotional functioning and sleep disorders among truck drivers in the State of São Paulo (nº 11/11682-0); Grant Mechanism Young Researcher; Principal Investigator Lúcio Garcia de Oliveira (USP); Investment R$414,498.01.