Design Of Embedded Ultrasonic Ranging System

This article mainly introduced the embedded design of ultrasonic ranging system based on AVR microcontroller,mainly realize the function of the membrane as matrix keyboard safe distance and the digital tube display,test distance by the LCD display,the DS18B20 temperature acquisition and display on the LCD and temperature compensation of ultrasonic distance measurement,and to determine the ultrasonic transmission speed,when the test distance is less than the safe distance,LED lights flashing alarm.The designed hardware operation platform USES ATmega128 single-chip microcomputer launched by ATMEL company.Ultrasonic probe,matrix thin film keyboard,LCD display screen and DS18B20 temperature sensor are connected with the designed hardware platform through the pin.First temperature detection,based on the current temperature value determine the propagation velocity of ultrasonic wave,a temperature compensation,and then by the ATmega128 send a high level trigger ultrasonic probe,by the receiving probe returns a high level,high level duration and ultrasonic time back and forth,the same need to calculate the echo duration in the process of software realization,and then through the T1 timer/counter timing and calculate the obstacle distance,and displayed on LCD and the distance to the PC through serial communication data,finally will test distance compared with by the keyboard input of a safe distance,When the distance is smaller than the safe distance,the LED light flashing alarm is controlled by ATmega128 pin with alternating output of high and low level.The system can work normally,and realize the functions of distance detection,display,data uploading and comparison.The system operation result is correct,which proves that the design idea is correct.