In the first two parts of this blog series, The Safety Assistant: How electronics technology will help drivers keep passengers safe, Part 1 and The Safety Assistant: How electronics technology can help drivers keep occupants safe, Part 2, I have introduced some examples of the application of electronics technology that could save the driver of a car from a dangerous situation like falling asleep during a long ride or the situation of a pedestrian crossing the street in a blind point of the driver, where the driver cannot brake to avoid a collision simply for the reason that he did not see the pedestrian. Are there other situations in which electronics could help improve the safety of the driver and pedestrians? My first example is a system that monitors the condition of an impaired driver and detects a potentially dangerous situation: a passive alcohol sensor (see Figure 1) installed in the car could recognize a dangerous level of alcohol by analyzing the breath of the driver and a warning message could be sent accordingly to the other occupants of the car:
“The PAS IV Screening System combines: a) high-intensity, super-beam flashlight technology with b) a dynamic sampling system and c) a miniature alcohol sensor. It “sniffs” ambient air, the breath, open containers, or enclosed spaces for the presence of alcohol. The PAS functions as a non-intrusive “extension of the operator’s nose”. This hand-held, rapid alcohol detection instrument uses a platinum electrochemical fuel cell sensor of high alcohol specificity, accuracy and stability.”
The PAS system integrates a sensor that creates an electrical current in the presence of alcohol. That electric signal may be routed to the input of a microcomputer installed into the car, which could implement preventive actions to preserve the safety of the occupants of the car, like for example to render the car inoperable in the case of detecting dangerous levels of alcohol revealed in the breath of the driver indicating an illegal and unsafe blood alcohol content of the driver (see Figure 2):
“Blood alcohol sensor technology might cause cars to shut down if they sense drivers are over the legal blood alcohol limit, it has been revealed. … Breath-based and touch-based sensors could be employed in vehicles. The breath-based system, the clip explains, could measure alcohol molecules in the driver's breath. For the other option, the video's narration says 'This touch-based system uses near-infrared tissue spectroscopy to detect the level of alcohol in the blood. 'Alcohol absorbs specific wavelengths light. By measuring the light's intensity, the system can precisely pinpoint the driver's blood alcohol level.' For both sensors, if the driver's blood alcohol is higher than .08 - which is the legal limit - the car will stay put… ” (Source: Daily Mail online)
The touch-based and breath-based system by the Driver Alcohol Detection System for Safety (DADSS). (Source: dailymail.co.uk)
Electronics technology give an important contribution to the safety of the drivers by preventing dangerous situations related to an excessive consumption of alcohol by the driver, provided that the overall system presents no false alarms in order to avoid stopping the car of a driver who has not exceeded the legal limit of alcohol content in the blood. Therefore, the accuracy of the alcohol sensor, which is the core of the system, is a key point in ensuring the overall system accuracy.
The block diagram of an electrochemical sensor for measuring gas molecule concentration in human breath (Source: Prezi)
Electronics technology can be a helpful means to guarantee the safety of the drivers, passengers and pedestrians by preventing a drunk driver from driving his car. Do you think this solution will reduce the number of accidents caused by the excessive consumption of alcohol?