Hitachi and Honda Motor Co
have announced they have successfully developed a prototype of a portable
alcohol detector that is tamper-resistant as it can distinguish human breath
from alternative gases and that can be integrated into smart key. This device
is capable of distinctively detecting the saturated water vapour from human
breath and accurately measuring alcohol level within 3 seconds once a driver
exhales breath onto the device. Hitachi and Honda jointly collaborated on this
technology development in an effort to create the ideal alcohol detector.
They also developed a system
that can show the alcohol level measured by the detector on the vehicle’s
display panel. It can become an ignition interlock to stop a vehicle starting
its engine when it detects a driver under the influence of alcohol.
The effort to prevent or stop
drunk driving is global and is an on-going focus of progress in safe driving
technology. In Japan, transportation operators are required to use an alcohol
detector to test whether professional drivers are under the influence of
alcohol before they begin their shifts. Meanwhile, in the U.S., the National
Highway Traffic Safety Administration (NHTSA) has launched and directed the
development of ignition interlock technology that connects alcohol detectors to
a vehicle’s engine.
The prototype developed by
Hitachi and Honda has advantages over the other ignition interlocks. These
other systems require drivers to perform the test from the driver’s seat once
they are already inside the vehicle. With the Hitachi/Honda device, drivers can
measure their alcohol level from anywhere and, importantly, prior to entering
their vehicle, thus reducing the temptation to drive. In addition, the
Hitachi/Honda device can confirm that the applied gas is human exhaled breath
and can detect the level of alcohol at the same time, an enhancement over
currently available devices. Advancements like these will contribute to
reducing or eliminating instances of drunk driving.
The features of this newly
developed technology are as follows:
(1) Achieved both portability and human breath
detection at the same time by making the saturated water vapors sensor very
small. Also saves power.
Hitachi has developed sensor
technology that can detect the saturated water vapors from human breath with a
high degree of sensitivity. When human breath is exhaled onto the sensor which
is an oxide insulator sandwiched between the electrodes, the water vapors from
the breath is adsorbed on the insulator and then an electric current flows
between the electrodes.
When this phenomenon occurs,
the sensor can recognise if the applied gas is human breath. Furthermore, micro
comb-shaped electrodes are used to extend the length of electrodes and to
narrow the distance between electrodes, improving the sensitivity of the
sensor. This enables the device to detect a tiny amount of saturated water
vapors even though the sensor area has been decreased to only a 5mm square. As
a result, the device is highly portable and can be used prior to a driver
entering his vehicle. The device is also battery powered that is achieved from
a design with the low power consumption technology.
(2) Achieved high accuracy
measurement of ethanol concentration using three types of semiconductor gas
sensors
In compliance with Japan’s
regulations related to drunk driving, the device has an improved ability to
accurately measure the ethanol concentration from exhaled breath. The ethanol concentration is measured*2 by
three types of semiconductor gas sensors to detect ethanol, metabolized
acetaldehyde in breath after drinking, and hydrogen. This method improves
accuracy by about three times*3 compared with devices that only use an ethanol
sensor for measurement. Also, the device is capable of measuring as little as
0.015 mg/L (an ethanol concentration) compared to 0.15 mg/L of the alcohol
which constitutes being “under the influence of alcohol” and a charge of drunk
driving in Japan.
(3) Developed a system that is
integrated into a smart key function
By applying the recorded
measurement result of the alcohol detector into the engine ignition mechanism,
the system can prevent the vehicle’s engine from starting if it detects that
the driver’s breath is over the preset limit. An alert indicator also shows the
measurement results on the vehicle’s display panel if the detector equipped
smart key is close to the driver seat.
When validating the efficacy
of this newly developed prototype, it was confirmed that the device can detect
whether drivers are under the influence of alcohol based on the Japan’s drunk
driving regulation within three seconds.
Hitachi and Honda are aiming
to commercialise this developed technology through effectively collecting data
from future validation tests.
Source: Honda Motor Co.