Design for reliability for the high reliability fuze

Sun²,

International Journal of Antennas and Propagation

et al. 2021

The present study proposed the equivalent test method for the strong electromagnetic field radiation of electric explosive devices (EEDs) of the weapon equipment to satisfy the military requirements of the electromagnetic radiation safety test, as well as the evaluation of the electric ignition, the electric initiation ammunition, or missiles. Under stable conditions, the ignition excitation test and the bridge wire temperature increase test were performed to determine the ignition temperature of the EED. As radiated by the strong electromagnetic field, the relationship between the temperature increase of the bridge wire and the electric field intensity of the EED was developed based on the theoretical analysis and the experimental test. Given the ignition temperature of the EED, the radiation field intensity of the EED at 50% ignition was determined. As compared with the 50% ignition field intensity of the EED directly radiated by the strong electromagnetic field, an error less than 1 dB was caused. On that basis, the correctness of the equivalent test method was verified. Accordingly, this method was suggested to act as an effective method and technical means to test and evaluate the electromagnetic radiation safety of ammunition and missiles in unfavorable electromagnetic environments.

Section: Introductionmentioning

confidence: 99%

Equivalent Test Method for Strong Electromagnetic Field Radiation Effect of EED

Sun²,

International Journal of Antennas and Propagation

et al. 2021

“…After infant mortality, there exists a stable, low failure rate (operational life) and finally increasing failure rate towards the end of life for electronic products. Sharp et al [19] discussed the design for reliability (DFR) for cluster munition fuze (CMF) with the reliability of more than 99%. They also explained the concept and introduction of redundancies in the case of a high-reliability application where human safety and operational reliability are required.…”

Section: Introductionmentioning

confidence: 99%

“…Here we have only four average values of detonating samples collected after 2.5 years. Equation (19) is used to calculate a prediction of future values in GM (1,1). Using the grey forecasting model GM (1,1) the values show that the total life of the detonator is more than 20 years, with the remaining useful life of more than 10 years as shown in Table 1.…”

mentioning

confidence: 99%

Reliability and Remaining Life Assessment of an Electronic Fuze Using Accelerated Life Testing

et al. 2020

An electronic fuze is a one-shot system that has a long storage life and high mission criticality. Fuzes are designed, developed, and tested for high reliability (over 99%) with a confidence level of more than 95%. The electronic circuit of a fuze is embedded in the fuze assembly, and thus is not visible. Go/NoGo fuze assembly mission critical testing does not provide prognostic information about electrical and electronic circuits and subtle causes of failure. Longer storage times and harsh conditions cause degradation at the component level. In order to calculate accrued damage due to storage and operational stresses, it is necessary to perform sample-based accelerated life testing after a certain time and estimate the remaining useful life of mission critical parts. Reliability studies of mechanical parts of such systems using nondestructive testing (NDT) have been performed, but a thorough investigation is missing with regards to the electronic parts. The objective of this study is to identify weak links and estimate the reliability and remaining useful life of electronic and detonating parts. Three critical components are identified in an electronic fuze circuit (1) a diode, (2) a capacitor, and (3) a squib or detonator. The accelerated test results reveal that after ten years of storage life, there is no significant degradation in active components while passive components need to be replaced. The squib has a remaining useful life (RUL) of more than ten years with reliability over 99%.

“…To realize the steady state with duty cycle time 0.3-0.5 of CFETR, Cao et al [12] studied the relations between steady-state operation with duty cycle time 0.3-0.5 and the reliability of divertor. Based on Probabilistic Design and Physics of Failure Analysis, Sharp et al [13] used the reliability design to mitigate the harms of armaments to civilians. By melding multi-source lifetime or failure information, Xu et al [14] proposed a reliability-based design optimization method based on the Bayesian Melding Method.…”

Section: Introductionmentioning

confidence: 99%

Complex Satellite Lifetime Optimization Based on Bayesian Network Reliability Compression Inference Algorithm

Zheng

Yao²,

et al. 2019

IEEE Access

In the satellite lifetime optimization, reliability is a critical issue. For the complex satellite system, Bayesian network (BN) is an important method for reliability modeling and inference. As the number of system's components increases dramatically, the memory storage requirements of the system's node probability table (NPT) will exceed the computer's random access memory (RAM). To solve this challenge, compression methods have been proposed to reduce the memory storage requirements of NPT. However, for the complex satellite system with extreme large number of components and the explosion of probable state combination, the existing methods still face big challenge in compression efficiency. Therefore, an improved encoding compression algorithm is proposed to further enhance the NPT compression effect in this paper. For the hierarchical complex satellite system that has multiple subsystems which are further composed of multiple components, the multilevel BN reliability model is first constructed based on the proposed encoding compression algorithm. By the variable elimination algorithm, a multilevel BN reliability inference algorithm is proposed to perform the inference of the multilevel BN reliability model. Based on the basis of the reliability model above, further considering system mass, power and cost requirement, the satellite lifetime is properly designed by optimizing the system component configuration, including component model/type selection and number determination for redundancy. Finally, two cases are studied to demonstrate and validate the proposed algorithms.