Research and Analysis of a Portable Precision Temperature Sensor

Based on the excellent performance of Pt100, a portable low-cost precision temperature sensor has been designed, whose core chips are REF03, AD8603, AD7788 and precision resistors. Constant current source (CCS) for 4-wire Pt100 is constituted by REF03, AD8603 and precision resistors. AD7788 measures the differential signal on Pt100 and suppresses the common mode interference signal. Analysis software running on the micro control unit (MCU) filters the digital code from AD7788, and then calculates the current temperature value according to the resistance-temperature mathematical model of Pt100. Analysis and experimental results show that the temperature measurement accuracy of the sensor can reach ±1°C within the range of 0°C-650°C.

Rapid Temperature Measurement of Meteorological Detection System Based on MEMS

This paper is based on a meteorological detection system, which contains MEMS barometric pressure sensors, MEMS temperature sensors, MEMS humidity sensors and GPS receiver. The micro control unit of this system is based on C8051F120 microcontroller. By Comparing SHTXX series of temperature and humidity sensor and PT100 thermal resistance, we obtain a measurement scheme that can measure environment temperature rapidly and relatively accurate when the volume, weight and power are limited. It can meet the harsh environments and high reliable needs. In addition, the simulation analysis and the experiment of temperature are carried out.

GPS Positioning System Design Based on Micro Control Unit

This device uses GPS module to sample the data, and transmits data with the wireless module. The handheld terminals can display information such as longitude, latitude, time independently. The transmitting section collects data which is parsed and processed by the MCU, and displays it on the Liquid Crystal Display (LCD). The receiver receives and analyses wireless data, then displays the data including the current geographic information through the upper machine at the same time. Experiments show that the device could realize the function of positioning and transferring information within 200 meters and we could also use Google Map, the PC software, to get map information. This device, compared with the traditional system, is small in size, light in weight, easy carrying and can accurately position an object. It can be widely used in the sphere of investigation, exploration, navigation and positioning.

Design and Research of Freescale Smart Car Keyboard in Mechanical Manufacturing Engineering

The keyboard is made up of a number of key switch matrix. It is the simplest digital input device of MCU (micro control unit). The operator inputs data or commands through the keyboard and realizes the communication between people and machine. In the process of Freescale intelligent car competition, many operations are completed by keyboard such as speed adjustment, mode switch, reference frame changing and so on. In order to improve the adaptive ability of intelligent car, the keyboard plays an important role. So the design of the keyboard also becomes a very critical process in smart car design.