Accelerated Degradation Reliability Modeling and Test Data Statistical Analysis of Aerospace Electrical Connector

As few or no failures occur during accelerated life test,it is difficult to assess reliability for long-life products with traditional life tests.Reliability assessment using degradation data of product performance over time becomes a significant approach.Aerospace electrical connector is researched in this paper.Through the analysis of failure mechanism,the performance degradation law is obtained and the statistical model for degradation failure is set up; according to the research on statistical analysis methods for degradation data,accelerated life test theory and method for aerospace electrical connector based on performance degradation is proposed by improving time series analysis method,and the storage reliability is assessed for Y11X series of aerospace electrical connector with degradation data from accelerated degradation test.The result obtained is basically consistent with that obtained from accelerated life test based on failure data,and the two estimates of product＇s characteristic life only have a difference of 8.7%,but the test time shortens about a half.As a result,a systemic approach is proposed for reliability assessment of highly reliable and long-life aerospace product.

Technical research on optimization design of contacts of electrical connector

Pin and socket contacts are the key parts of electrical connector as aerospace electronic components. The contacts are also the direct carriers for signal transmitting of electronic equipments, passing the signal from the input end to the output end of electrical connector. The reliability of pin and socket contacts directly influences signal transmission. The goal of this study is to enhance the contact reliability of aerospace electrical connector. Computer simulation analysis was made on contacts performance data by utilizing the simulation system developed by PCL Language of MSC software. Furthermore, the results were experi- mentally validated so as to realize the objective of optimizing contacts design.

Step-stress Accelerated Degradation Test Modeling and Statistical Analysis Methods

In order to get a rapid assessment on the storage reliability of high-reliable and long-life products within the storage period, accelerated degradation test data with a large amount of reliability information of product is adopted. Conducting a constant-stress accelerated degradation test（CSADT） is generally very costly as it requires a large sample size and long time for test. To overcome this problem, it is necessary to carry out research on modeling and statistical analysis methods of step-stress accelerated degradation test （SSADT）. Taking electrical connectors as the object, a research is conducted on statistical model and assessment method for SSADT. On the basis of mixed-effect degradation path model, the statistical model of SSADT for electrical connectors is presented, the maximum likelihood method for SSADT data based on mixed-effect degradation model is proposed. SSADT accelerated by temperature stress is conducted to Y11X-1419 type of electrical connectors, and the storage reliability is assessed with the SSADT data. Compared with the result obtained from accelerated life test, the reliability estimation of 32-year storage period for electrical connectors obtained from S SADT data only have a difference of 0.869%, which validates the accuracy of the degradation model and the feasibility of the test data statistic analysis method put forward.

Lifetime prediction of electrical connectors under multiple environment stresses of temperature and particulate contamination

Electrical connectors play a significant role in the electronic and communication systems. As they are often exposed in the atmosphere environment, it is extremely easy for them to cause electrical contact failure. It is essential to carry out the reliability modeling and predict the lifetime. In the present work, the accelerated lifetime testing method which is on account of the uniform design method was designed to obtain the degradation data under multiple environmental stresses of temperature and particulate contamination for electrical connectors. Based on the degradation data, the pseudo life can be acquired. Then the reliability model was established by analyzing the pseudo life. Accordingly, the reliability function and reliable lifetime function were set up, and the reliable lifetime of the connectors under the multiple environment stresses of temperature and particulate contamination could be predicted for electrical connectors,

A Novel Model of Failure Rate Prediction for Circular Electrical Connectors

The reliability of electrical connectors has critical impact on electronic systems. It is usually characterized by failure rate prediction value according to standard MIL-HDBK-217(or GJB-299 C in Chinese) in engineering practice. Given to their limitations and mislead results, a new failure rate prediction models needs to be presented. The presented model aims at the mechanism of increase of film thickness which leads to the increase of contact resistance. The estimated failure rate value can be given at different environmental conditions,and some of the factors affecting the reliability are taken into account. Accelerated degradation test(ADT) was conducted on GJB599 III series electrical connector. The failure rate prediction model can be simply formed and convenient to calculate the expression of failure rate changing with time at various temperature and vibration conditions. This model gives an objective assessment in short time, which makes it convenient to be applied to the engineering.

Prediction of electrical contact endurance subject to micro-slip wear using friction energy dissipation approach

Fretting wear is a common cause of failure of an electrical contact(EC). In this study, we analyzed in detail the failure of EC induced especially by sliding using the representative electrical terminals. Furthermore, combining the friction energy dissipation theory, we proposed a prediction model to evaluate the electrical connector endurance(ECE) based on the contact stress and geometrical changes during the wear process obtained from a numerical model. The study helps establish that the friction energy dissipation theory is a powerful tool to analyze a contact failure due to wear. The proposed model proves to be effective in predicting the ECE for all considered cases such as micro-slip amplitude, contact force, overturning angle, superficial layer thickness, and friction/wear coefficients.

Programmable quantum logic gates using teleportation with non-maximally entangled states

A scheme is proposed for involving programmable quantum logic gates via teleportation,which is a unique technique in quantum mechanics.In our scheme,considering the inevitable decoherence caused by noisy environment,the quantum states are not maximally entangled.We show the implementation of single qubit quantum gates and controlled-NOT(C-NOT) gate,which are universal quantum gates.Hence,any quantum gate can be implemented by using teleportation withnon-maximally entangled states.Furthermore,two schemes in differet connections of universal gates are proposed and compared,and our results show the parallel connection outperforms the cascade connection.