| Air-condition of automobile is the abbreviation of equipment that regulating air. Namely, using some equipment to control the temperature, humidity of air, air quality and air flow, so that creating fresh and comfortable environment on the car. The ability that air-condition accommodate the environment is more and more becoming standard to evaluates the comfortableness of the car.So, testing the performance of the air-condition before soling in order to increase repair rate is gently request of the factory.The automobile test system of air-condition that was originally designed in the thesis is the horizontal subject of cooperating with second car factory of the First Automobile Factory of China. Though there are many factors that control the comfortable feels of human being, the most important ones are temperature, humidity, and wind speed. The system that is designed to test temperature, humidity, and wind speed of air-condition installed in the red flag car. The research work presented in this paper designs hardware, software, and methods of processing data. 1. Design precept of the testing system A testing system is consisting of sensor, signal process part and display part. It is need to install three types sensors that output signals is digital data in order to omit to use A/D convertor , to measure temperature, humidity and wind speed. After measuring the signals, it is delivering to computer to processing. Sensors should be installed close to air-condition ,because of the car is moving on the line, while worker watch on the data in the workshop, the solution is dived the test system into two parts, one part is in the cars the other one is in the workshop, two parts are depend on wireless to communicate data.2. Method to measure the performance of air-condition 1) Measure the wind speed of air-conditionThe wind speed of air-condition is measured by hot ball anemograph of QDF produced in Beijing, it consist of the hot ball head and instrument. Consider of the narrow space of car, we only use the head part. The signal is exported in voltage form that offered and encouraged by permanently source. The exported voltage is the level of mV, after enlarging to the level of V by the amplifier and changed to digital signal by ADAM 4017 module; it was send to serial communication interface of biscuit computer after changed by RS232/RS 485.2) Measure the temperature of air-conditionIn the course of testing the air-condition, it need to multi-measure the temperature in order to acquaint the distribution situation of temperature, improve exactness of measuring and alleviate the worker's word force. We use LTM8301 module and DS18B20 temperature sensor that produced by Changying technologies co.Ltd to measure the temperature of air-condition.The course of measuring temperature of air-condition is that: Make the temperature sensor close to air-condition outlet, and then send data to module. Modules deliver the data to serial communication interface of biscuit computer through RS-232/ RS-485 convertor. CPU control PTR2000 module deliver out the data after receiving and storing them. Industry computer then control PTR2000 to receive, examine and deposit data in corrects in order to show them.3) Measure the humidity of air-conditionIn the course of measuring the humidity of air-condition, we select to use module LTM 8301, cooperating with LTM8802 humidity sensor to measure it. The course of measuring the humidity is the same as course of measuring temperature; the only difference is the forms of reading. 3. Wirelessly deliver and receive module In order to complete the he wireless communication function, we select to use PTR 2000 MODEM that produced by Xuntong technology co.Ltd. This module has some characteristics as follows: it can both receive and deliver, can operate with 433 MHz frequency, has strong ability, especially suitable for industrial control occasion. The module can link to serial communication interface of the computer directly, but the PTR2000's logic regulation is diff...
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