激光测距系统设计

　　激光测距系统设计
　　摘要：本课题从设计1种成本低、工作稳定的高性价比车用LD测距仪出发，分别对测距仪的工作原理及参数确定、
　　发射驱动电路、光学系统、接收探测电路和软件 信号处理方面进行了分析和优化设计，设计了1种利用激光脉冲对车间距离进行测量的汽车防追尾碰撞系统，这是1种主动汽车安全系统。在激光从发射到接收这段时间范围内，通过充电电路对电容进行充电，充电结束时的电容端电压即与激光飞行时间相对应，然后通过A/D转换器转换成相应的数字量，再送人单片机进行分析处理，将相应的时间间隔换算为车间距离进行显示并驱动声光报警系统，从而提醒司机采取紧急措施以避免与前车发生碰撞等事故。所设计的LD测距仪达到了6 150m的测量量程和 1m的测距精度，工作 稳定可靠，对提高驾乘的安全性有良好的实用价值。
　　关键词：激光测距仪；汽车防撞；激光脉冲
　　The Range Acquisition of Laser System
　　Abstract：A LD rangefinder is designed which has the characters of low cost,reliable and high performance to price
　　ration.Optimal design of the laser rangefinder is discussed according to the system’s applied demand,laser transmit driver circuit,option system,laser detection circuit and signal process software.In this paper，vehicle rear-end collision avoidance system is discussed and studied which uses laser impulse to measure the distance between two vehicles．It is a kind of active safety system。The capacitance is charged through a kind of charging circuit during time intevals of laser impulse from sending out to receiving 。When it ends up charging ，we can get its voltage which is resistant to the time intevals of laser impulse，transform it into a certain figure by ADC convertor，then input the figure into the computer to analyze，changing the data into distance to display ，besides that，we can use it to drive voice and light panalarm to remind the driver of avoiding rear-end collision accident。The laser rangefinder used in antomobile crashworthy system can get 150m measured range and measurement accuracy easily,and improve security of drive and ride effectively,which confirms that the laser rangefinder is practicable.
　　Keywords:laser rangefinder;automobile crashworthy;laser burst