无人机载数据记录仪软件的实时性分析与优化

为了给飞行安全、 维护管理以及训练提供重要数据保障, 设计了无人机载数据记录仪, 对该记录仪软件的实时性进行了研究。对影响数据记录仪软件实时性的因素进行分析, 根据所需记录数据的帧长度及中断频率得到数据记录仪对中断响应延时的要求； 利用软件设置GPO（General Purpose Output）翻转, 结合示波器测得存储单元在不同寻址方式下的响应时间延时； 再根据寻址响应延时及乒乓缓存深度关系得到最优记录模式。通过搭建测试平台对优化前后的数据记录仪软件进行测试。结果表明, 优化后的数据记录仪最短中断响应时间间隔为56 μs。该数据记录仪能实时记录所有中断源数据, 丢帧率为0, 满足无人机对数据记录仪的高实时性要求。

Analysis and Optimization of Real-Time Software in Data Recorder Based on UAV

In order to provide important data protection for flight safety, flight maintenance and flight training, a data recorder is designed and its embedded software is investigated. First, analyze the key factors which influence the real-time data recorder software and figure out the interrupt response delay requirements according to the records of frame length data and the interrupt frequency. Then measure the interrupt response delay under different addressing modes by use of software GPO（General Purpose Output） and oscilloscope. Finally optimize the addressing recording mode according to the relationship between delay and ping-pong buffer depth. A platform is built to test the data recorder software. Experimental results indicate that the optimized software has shorter interrupt response time interval than non-optimized one. The shortest interval can reach 56 microseconds. The recorder can record all the interrupt source data with no missing data. It can satisfy the system requirements of real time and rapid speed.