传统仪器设计过程回顾现代化的自动仪器设备均具有如下几方面的性能和特点前端的信号检测，适时数据采集，数据处理，实现其功能的光机电一体化的自动装置，以及人机操作界面，除此之外还必须有完备的上下位机的控制程序软件包。为实现以上几个方面的性能，以高性能的微处理器为基础的嵌入式单板机就似乎成为迄今仪器设计的选择。从而，在仪器具体的性能要求确定以后，单板机的软硬件设计制造工作就进入议事日程。这项工作是非常专业和浩繁的，比较小的公司不可能储备如此多的专业技术人员，所以靠自身的技术力量是无法完成的。为此就必须支付高昂的设计开发费用，而且，整机软硬件及外部设备的联调也需要大量的时间以及返工和重新设计。同样，大公司也并非不存在类似问题。特别是在新技术新方法摸索创新的样机试制阶段设计过程详实（以自动生化分析仪为例自动生化分析仪是用于医院临床检验血液生化指标的复杂仪器，在分析类仪器中，它的复杂程度是高的生化分析仪的基本功能是按照各自不同的生化方法要求设定测试参数，然后自动机构取样并按照设定对各样品及同一样品不同测试加入所需的试剂，按所需特定比例进行稀释。进而分别注入比色杯对反应液进行保温和延时（经稀释后的样品称为反应液下一步对反应液按照所需编排好的测试方法和时间进行测试，后计算并储存和打印测试结果。仪器的具体构造此不赘述从而得到生化分析仪对电子系统的软硬件要求,并据此选择PLC的软硬件配置。

Review of traditional instrument design process modern automatic instruments and equipment have the following performance and characteristics: front-end signal detection, timely data acquisition, data processing, optical electromechanical integration automatic device to realize its functions, and man-machine operation interface. In addition, there must be a complete control program software package for upper and lower computers. In order to achieve the above performance, the embedded single board computer based on high-performance microprocessor seems to be the only choice for instrument design so far. Thus, after the specific performance requirements of the instrument are determined, the software and hardware design and manufacturing of the single board computer will enter the agenda. This work is very professional and numerous. It is impossible for a relatively small company to reserve so many professional and technical personnel, so it is impossible to complete it with its own technical strength. Therefore, high design and development costs must be paid, and the joint commissioning of the software and hardware of the whole machine and external equipment also requires a lot of time, rework and redesign. Similarly, large companies are not without similar problems. In particular, the design process is detailed in the trial production stage of exploring innovative prototypes with new technologies and methods (take the automatic biochemical analyzer as an example. The automatic biochemical analyzer is a complex instrument used for clinical testing of blood biochemical indicators in hospitals. Among the analytical instruments, its complexity is the highest. The basic function of the biochemical analyzer is to set the test parameters according to the requirements of different biochemical methods. Then, the automatic mechanism samples and adds the required reagents to different tests of each sample and the same sample according to the settings, and dilute them according to the required specific proportion 。 Then inject the cuvette respectively to keep the reaction liquid warm and delay (the diluted sample is called the reaction liquid). Next, test the reaction liquid according to the required test method and time, and finally calculate, store and print the test results. The specific structure of the instrument is not described here, so as to obtain the software and hardware requirements of the biochemical analyzer for the electronic system, and select the software and hardware configuration of PLC accordingly.