Abstract
In recent years, China's rapid economic development, increasing people's standard of
living, the number of motor vehicles and drivers has soared, drunk driving has caused
serious consequences of illegal crime is also increasing, to the society and the life of
the masses, causing serious harm to health. Since 2000, drinking and driving behavior
caused by increasing number of accidents, on the social impact is also growing,
alcohol has become fierce" killer on the road". According to the statistics, the whole
world because of traffic accident every year the number of people killed more than
600000 people, left permanently disabled in 4000000 above, general injuries are too
many to count. In many countries, traffic accident has become the first cause of
accidental death. In addition, the traffic accidents caused by the economic loss is quite
amazing. According to statistics, approximately 50% - 60% of the accidents are
related to alcohol. China public security departments in 2009August, throughout the
country to strengthen and driving force, so as to reduce the driving caused by
malignant traffic accident. To investigate the related to detection of human with an
alcohol content and the use of equipment to detect problem.
In recent years, industry of our country coal production safety situation is not
optimistic, middle and small coal mine situation is particularly serious, has a direct
threat to the stable production of the whole coal industry, to the national property and
people's lives and caused great damage, as" the worst of all evils" methane explosion
is a major accident rate in the first. For security reasons, the methane concentration
measurement, appear particularly important.Based on the above, the gas concentration
detection problem, critical. This paper studied and designed a variety of gas
concentration can be measured, and can alarm intelligent tester. The design scheme
based on STC89C52 MCU, MQ3 alcohol concentration sensor, MQ4 methane
concentration sensor. System circuit of the sensor output signals from the AD0832 as
the core of the A / D conversion circuit after conditioning, through the single-chip
microcomputer for data processing, LCD display by the alcohol concentration value.
And the design of certain limits, overrun alarm. Limit value by the keys to adjust.
Considering the SCM calculation ability is limited, to complex data processing, so
single-chip system and PC system through the RS-232 serial communication port
interconnect, thereby SCM as the next bit machine data acquisition and control
equipment, and the machine used PC do PC for complex data processing and the
SCM control. This paper introduces the data acquisition subsystem, data processing
and data display system and alarm circuit, SCM and PC communication hardware and
software to achieve the design method and process. System for sampling locations
beyond the prescribed specified gas concentrations, through sound and light alarm
circuit to remind staff monitoring. At the same time, the operator for a specific alarm
limit values can be set through the single-chip programming.
Key words: alcohol oncentration sensor (MQ3), methane concentration sensor
( MC113), STC89C52, A/D converter,Dataelector (74HC4051), serial communication,
RS232,VB;