The Design And Development Of Large Distance Ultrasonic Range Instrument Based On ARM

In recent years,with the rapid development of Chinese urbanization,tower crane which is the basic transport equipment in construction industry has been great development and the tower cranes in construction site are increasing in number.The accidents of tower cranes occurred frequently because of the complex workplace and high strength work.The collision and fall of tower cranes is the worst accident.Immature tower crane anti-collision technology restricted the development of tower crane industry badly.It is very important to develop mature and reliable tower crane anti-collision technology.In this paper,the tower crane anti-collision technology based on ultrasonic detection is studied.The purpose is to design a kind of miniaturized ultrasonic distance measuring instrument.It improve the scope of application and reduce costs of the instrument.Firstly,a new Least Mean Square Adaptive Time Delay Estimation(LMSTDE)in ultrasonic echo time delay estimation which is based on Discrete Particle Swarm Optimization(DPSO)Algorithm was proposed.This method not only keep the high accuracy and good antinoise ability of the original algorithm,but also increase the computation speed by 25 times.It can be used in the real time detection of middle and long distance obstacles and its reliability is high.Ranging equipment can be divided into two parts: hardware circuit design and software function development.For the hardware circuit,it used ultrasonic transducer DYA-25-20 C and the Micro controller is STM32F4.It used pulse transformer to increased driving voltage.The receiver module can be divided into band pass filter and amplifying circuit.It used MF50 to Measure temperature in order to fix sound velocity.Serial communication module is used to transmit data from host computer to slave computer.For the software,the ARM program wrote by C language is used to transmit PWM,collect signal,measure temperature,fix sound velocity and calculate distance.The final chapter test the working performance of ultrasonic transducer driving signal,Band pass filter,logarithmic amplifier circuit and algorithm of distancemeasurement.The result show that the new algorithm of distance-measurement is stronger than others and the ultrasonic distance measuring instrument have a good working performance.