Design of Testing Equipment for Electronic Products
|School||Harbin Institute of Technology|
|Course||Mechanical and Electronic Engineering|
|Keywords||Automatic test equipment Mechanical Design Finite Element Analysis Signal processing Wavelet Denoising Counting method|
Combustible gas alarm is the device that could monitor the concentration of combustible gases in the air automatically. It could performance stably with a compact structure, and it consumes little power. The circuit board, which is the most important component of the alarm, need to be inspected to ensure the quality of the product in production process. At present, the monitoring equipment of the circuit board is usually special for the product domestic and abroad, which is also very expensive. This paper designs an auto testing equipment for combustible gas alarm which could finish positioning, clamping and testing. This testing equipment costs lowly and is maintained easily. It is very suitable for on line testing rapidly.This paper includes the design of the positioning and clamping mechanism for the circuit board firstly. The size of the key parts of the structure is determined by dynamic analysis of the device. And appropriate driving components are selected suitably. The finite element analysis of the key components is finished through simulation software. That is to ensure the carrying capacity of parts and security of operation. Finally the structure of the parts that can’t bear the maximum stress is optimized for normal operation. This analysis process is very necessary for safe and stable operation of the equipment.A microcontroller is used as the core of the testing and motion control system which could acquire signal of the tested node, judge the results of the node, and it also controls the motion of the lifting and clamping mechanism. The system includes a communication interface, and this left the opportunities for function expansion and further analysis of the testing result in the future. Many experiments are applied to analyze the performance of the hardware system, and it could also determine the parameters of many electronic components. According to the working process of the testing and control system, the software is designed to complete test tasks successfully through many repeated debugging.At last the paper studies the methods of digital signal processing. Testing signal usually includes some noise. Method based on wavelet analysis is used to process the testing signal. The paper chooses a suitable method of wavelet analysis through many experiments. The method this paper applied is of many advantages compared with other methods. Counting method is combined with median method so that the interference of the signal could be ignored to ensure that the testing results are accurate.