Electro-explosive Devices Research Articles

Calculation, Simulation, and Measurement of Input Impedance and RF-Induced Current of Bridgewire Electro-Explosive Device

Calculation, Simulation, and Measurement of Input Impedance and RF-Induced Current of Bridgewire Electro-Explosive Device

Measurement, calibration, and verification on the critical ignition temperature of hot bridge wire electro-explosive device

To address the problem of the difference in temperature between the exposed and amorce-filled state of the bridge wire in the fiber optic thermometry, this paper proceeds from a mathematical model of the temperature rise of the hot bridge wire electro-explosive device (EED), the relationship between the critical ignition temperature and the current of hot bridge wire EED is discussed. Combining thermal ignition theory, the technique of measurement and calibration the critical ignition temperature of hot bridge wire EED is proposed, and the technique is validated by injection versus radiation. The results show that the critical ignition temperature of the tested hot bridge wire EED obtained by testing and calibration is 337.53 °C. The 50% ignition field strength of the hot bridge wire EED under radiation conditions obtained by the up-and-down method test is 1271 V m−1, while the equivalent ignition field strength determined from the critical ignition temperature under the same radiation conditions is 1345 V m−1, the error between the two is only 0.49 dB, which demonstrates the high accuracy of the proposed measurement and calibration technique.

Simulation and experimental on sensitive criterion of hot bridge wire EED

To address the problem of complex process and inaccurate results in the simulation for the sensitivity of hot bridge wire electro-explosive devices (EEDs) which is caused by subjective factors in the sensitive criterion, this paper established a temperature rise model for the hot bridge wire EED first, then, through theoretical and numerical analysis, the sensitive criterion of hot bridge wire EED was proposed, and based on the sensitive criterion, the simulation process for the critical ignition current of hot bridge wire EED was given, finally, the correctness of the proposed sensitive criterion was verified by simulation analysis and experimental tests. The simulation results show that the critical ignition current of the tested EED under constant current condition is 182.6 mA and the ignition temperature is 481.52 °C, the maximum error between the ignition temperature under pulse excitation and that under constant current excitation is 7.75 %. The experimental test showed that the 50 % ignition current of the tested EED under constant current condition is 189.4 mA, with an error of only 0.32 dB from the theoretical calculation, demonstrating the correctness of the theoretical model and the sensitive criterion.

Simulation on correlation of pulse ignition sensitivity for hot bridge wire EED

To solve the problem of testing the sensitivity under electromagnetic pulse radiation for a hot bridge wire electro-explosive device (EED), this paper simulated and analyzed the correlation between the critical ignition current under steady and pulse excitation. The simulation results showed that, under single pulse excitation, the critical ignition current of the EED decreases with the increase in the pulse width, and the variation law can be divided into three pieces: adiabatic, transition, and constant; while under pulse train excitation, due to the thermal cumulative effect, the critical ignition current is related to both material properties and excitation parameters. By analyzing the simulation results and considering the thermal ignition theory, the mathematical model of the critical ignition current under pulse excitation was established, and the mathematical model showed that under pulse train excitation, the critical ignition current is relevant not only to the single pulse excitation critical ignition current, pulse period, and duty cycle, but also to the ratio of single pulse and steady excitation critical ignition current and the thermal time constant. It was verified that the errors between the theoretical values obtained from the mathematical model and the results obtained from the simulation were within 2.5%.

Electromagnetic Compatibility Time Domain Response Characteristics of EEDs

The theory and algorithm of electric initiation are applied to the study of time-domain response of electromagnetic compatibility of electro-explosive devices(EEDs). based on the antenna theory and transmission line theory, the mathematical model of electromagnetic wave time domain response of different signal characteristics of EEDs was established, and the time domain response characteristics of electromagnetic field of typical EEDs were calculated and analyzed. The time domain characteristics of response of EEDs in electromagnetic field were tested and studied based on the characterization method of electromagnetic induction energy of transducer. The experimental results are consistent with the calculated results.

Effect of Electrostatic Discharge (ESD) on Heat Response Performance of NiCr Micro-heater

The NiCr micro-heater is a key element of MEMS-based electro-explosive device (mEED), while electrostatic discharge (ESD) may excite the micro-heater accidentally. To discover mechanism that how the ESD excitations effect on heat response performance of NiCr micro-heater, electro-thermal conversion process was numerically modelled by using commercial software. Three different shapes of micro-heaters, including rectangular, V-shape and square ones, are designed, and a series of simulation models are built under ESD events of 25kV, 5000Ω, 500pF and 25kV, 500Ω, 150pF. Heat response performance of NiCr micro-heater with different shapes and sizes were numerically computed under the said ESD events and compared with. The critical safety value at which LTNR and copper azide would not be ignited accidentally were calculated according to the fitted formulas. Conclusions are that maximum temperature decreases exponentially with increase of width of rectangular micro-heater, decreases exponentially with increase of wm and α of V-shape micro-heater, and decreases exponentially with increase of length or width of square micro-heater. The ESD event of 25kV, 500Ω, 150pF is a more severe case for micro-heater than ESD event of 25kV, 5000Ω, 500pF. These results could supply critical data to guide the design of MEMS -based EED for ESD protection.

Fabrication and performance of a nickel-chromium (NiCr) igniter integrated with TVS diode for ESD protection

The NiCr igniter is a key element of MEMS-based electro-explosive device (mEED), while electrostatic discharge (ESD) may excite the igniter accidentally. To protect the NiCr igniter from damage by ESD, a novel NiCr igniter by integrating the igniter onto a TVS diode based substrate was designed and fabricated through semiconductor technology. The microscope photograph, resistivity, breakdown voltage, firing performance, and ESD protection ability were tested. The results show that the surface of the chip is smooth, the edges of key structures are clear, and there are no major scratches, cracks, and other phenomena on the whole device. The resistivity of all the TVS-mNiCr igniters is between 5 and 7 Ω, and the TVS diode resistance value is normal. The breakdown voltages of the eight types of TVS diodes with different structures are all between 3.5 and 5 V, and the TVS-mNiCr igniters can fire reliably at a constant current of 2 A. After the ESD test, the microscope of the igniter does not change significantly, meaning that the TVS-mNiCr igniter chip has a certain ability of ESD protection. It is of vital importance to guide the design of electrostatic tolerant ability for the MEMS-based electro-explosive device.

Numerical simulation of the ignition law for a hot bridge wire electroexplosive device

Hot bridge wire electroexplosive devices (EEDs) are widely used as starting elements in aerospace and other fields. Their thermal ignition process and safety testing technology have always been a focus of research. In this paper, we construct a temperature rise model for a hot bridge wire EED by using the law of conservation of energy, and the temperature response of the bridge wire and the reagent is obtained. According to the theoretical and numerical analysis, the sensitive criterion for a hot bridge wire EED is given, and the simulation process for the critical ignition current is designed. Based on this process, the law of the influence of the bridge wire and reagent parameters on the ignition of a hot bridge wire EED was studied. The research results show that a first derivative of the reagent temperature with respect to the radial distance of greater than zero is a sensitive criterion for the ignition of a hot bridge wire EED with high accuracy. Compared with traditional numerical methods, the proposed process makes the acquisition of the critical ignition current more precise and programmable due to the use of sensitive criteria. In addition, the following significant features are noted: the critical ignition current first increases as the square root of the bridge wire radius and then linearly; the square of the critical ignition current increases linearly with the activation energy of the reagent; there is rapid exponential decay of the critical ignition current with increasing reagent combustion heat; asymptotic values are present. In engineering use, it is possible to conveniently design the ignition characteristics of a hot bridge wire EED by changing the radius of the bridge wire. This study serves as a foundational work for the safety testing of hot bridge wire EEDs and can provide theoretical guidance for the safety testing, actual production and use of hot bridge wire EEDs.

The Ignition Performance of Metal Film Bridge

The ignition voltage of micro-satellite and MEMS fuse become more and more lower, the conventional electro-explosive devices are hardly meet the requirement. In this paper, Ni-Cr metal film bridge of different size/substrate were designed by MEMS processing technology. By using Neyer D-optimal sensitivity test method, it got the result that the threshold of ignition voltage would decrease with the decrease of designing size, and the threshold of ignition voltage with the glass substrate would be less than the silicon substrate.

Lumped Parameter Analysis of Bridge Wire in an Electro Explosive Device of a Power Cartridge for Water-Jet Application: A Case Study

Lumped Parameter Analysis of Bridge Wire in an Electro Explosive Device of a Power Cartridge for Water-Jet Application: A Case Study

Novel Electro-Explosive Device Incorporating a Planar Transient Suppression Diode

In this letter, a novel, electrostatic discharge tolerant, semiconductor-based electro-explosive device was presented. The device which was called integrated semiconductor bridge (ISCB) chip consists of a monocrystalline silicon heating element, which was utilized to ignite pyrotechnic mix in weapon. Two planar transient suppression diode arrays were incorporated into the chip to protect against electrostatic discharge events. The characteristic of transient suppression diode array and electric discharge characteristic of the ISCB was tested by a capacitive discharge unit. Meanwhile, the behavior of the ISCB during electrostatic discharge events was also tested with a human body electrostatic discharge model. The results showed that the ISCB chip provided advantages including small size, fast ignition, electrostatic discharge insensitivity and low initiation energy applications.

Experimental simulation of self-powered overload igniter based on Lead Zirconate Titanate

In order to study the ignition performance of self-powered overload igniter based on Lead Zirconate Titanate (PZT), shock simulation tests for different electro-explosive devices (EED) were carried out by using separated Hopkinson pressure bar to simulate overload environment. The output energy of PZT, temperature rise process of bridge wire in EED, initiation temperature of the detonator, ignition energy, and initiation delay of igniter are experimentally analyzed. The experimental results show that: 1) the matching degree between the resistance of EED and PZT plays a key role in the sensitivity of the igniter; 2) Whether the igniter can detonate successfully depends not only on the maximum overload but also on the overload action time; 3) During the ignition process, the initiating explosive starts to react before the bridge wire fuses; 4) There is a delay time from the output energy to the reaction temperature of the initiating explosive to the complete reaction of the initiating explosive, which is the main reason for the delay of the igniter.

World’s first spaceflight on-orbit demonstration of a flexible solar array system based on shape memory polymer composites

With a 10% reversible compressive strain in more than 10 deformation cycles, the shape memory polymer composites (SMPCs) could be used for deployable structure and releasing mechanism. In this paper, without traditional electro-explosive devices or motors/controllers, the deployable SMPC flexible solar array system (SMPC-FSAS) is studied, developed, ground-based tested, and finally on-orbit validated. The epoxy-based SMPC is used for the rolling-out variable-stiffness beams as a structural frame as well as an actuator for the flexible blanket solar array. The releasing mechanism is primarily made of the cyanate-based SMPC, which has a high locking stiffness to withstand 50 g gravitational acceleration and a large unlocking displacement of 10 mm. The systematical mechanical and thermal qualification tests of the SMPC-FSAS flight hardware were performed, including sinusoidal sweeping vibration, shocking, acceleration, thermal equilibrium, thermal vacuum cycling, and thermal cycling test. The locking function of the SMPC releasing mechanisms was in normal when launching aboard the SJ20 Geostationary Satellite on 27 Dec., 2019. The SMPC-FSAS flight hardware successfully unlocked and deployed on 5 Jan., 2020 on geostationary orbit. The triggering signal of limit switches returned to ground at the 139 s upon heating, which indicated the successful unlocking function of SMPC releasing mechanisms. A pair of epoxy-based SMPC rolled variable-stiffness tubes, which clapped the flexible blanket solar array, slowly deployed and finally approached an approximate 100% shape recovery ratio within 60 s upon heating. The study and on-orbit successful validation of the SMPC-FSAS flight hardware could accelerate the related study and associated productions to be used for the next-generation releasing mechanisms as well as space deployable structures, such as new releasing mechanisms with low-shocking, testability and reusability, and ultra-large space deployable solar arrays.

In Situ Synthesized MEMS Compatible Energetic Arrays Based on Energetic Coordination Polymer and Nano-Al with Tunable Properties.

Integrating energetic materials with a microelectromechanical system (MEMS) to achieve miniaturized integrated smart energetic microchips is promising. The potential applications include actuation in lab-on-a-chip devices, ignition in automobile airbags, propulsion and attitude control of micro-/nano-satellites, and miniaturized electro-explosive devices. In this work, a new type of MEMS-compatible energetic arrays was in situ realized on a copper substrate, which comprised a new energetic coordination polymer (ECP; Cu1.5C2N8O2·H2O) with tunable nanostructures and a nano-aluminum (nano-Al) covering layer. The composition, morphology, and energetic characteristics of the energetic arrays can be easily tuned by adjusting the reaction time. The maximum heat release of 1850.2 J/g in thermal analysis and the intense flame in open burning experiment proved its excellent exothermic and combustion performance. A closed-bomb experiment further revealed that the ECP@nano-Al energetic arrays supported on Cu(OH)2 nanorods had a peak pressure (5.5 MPa) and a pressure duration (0.5 s) more than twice those of nanoscale Al/CuO powder because of the introduction of gas elements (e.g., C, H, and N). A preliminary impulse experiment was also conducted through the torsion pendulum method. The displacement of the torsion pendulum in the micrometer scale proved the potential application of the energetic arrays in micropropulsion systems. Overall, this work can serve as a reference for the synthesis and applications of ECPs.

A Device for Nanosecond Initiation of Powerful Shock Waves

A highly stable and highly efficient electroexplosive device for initiating powerful shock waves that contained a detonator based on a narrow copper foil coated with a polymer film and a semiconductor generator of submicrosecond current pulses that provides an electric explosion of the foil in a time of ~70 ns are considered. The possibility of using the developed device for detonating powerful explosives that are resistant to thermal and mechanical external influences is demonstrated.

Optimal design of simple step-stress accelerated life tests for one-shot devices under Weibull distributions

One-shot devices, such as rockets, airbags of automobiles, and electro-explosive devices, can be used only once and will be extensively destroyed. The actual lifetimes of the devices cannot be observed, no matter whether the outcomes are successful or not. Step-stress accelerated life tests, which are useful for shortening the lifetimes of devices and quickly collecting lifetime data in a limited time, are widely adopted in engineering reliability studies. However, optimal designs of step-stress accelerated life tests for one-shot devices have not been well studied. This paper provides a procedure of determining optimal designs of simple step-stress accelerated life tests for one-shot devices by minimizing the asymptotic variance of the maximum likelihood estimate of reliability at normal operating conditions under Weibull distributions, with respect to inspection times and sample allocations. Comprehensive simulation studies are carried out to study the optimal designs under Weibull distributions with various hazard rates, showing that the optimal designs can maintain the simulated standard deviations at the nominal level of standard error. Besides, sensitivity analysis is conducted to evaluate the robustness of determined designs when mis-specification on planning values of model parameters exists. Finally, an application in grease-based magnetorheological fluids is presented to illustrate the optimal designs.

On the Differential Input Impedance of an Electro-Explosive Device

In this paper, a model for the input impedance of a hot-wire electro-explosive device (EED) based on differential-mode measurements is proposed. The model represents the EED using three transmission line segments in cascade. The characteristics of each segment are estimated according to data reported in the literature and to measurements of the differential-mode input impedance of actual EEDs in the ultrahigh frequency range. The experimental procedure and model are presented in detail. In addition, the impedance measurements and the predictions of the proposed model are compared with previous results reported in the literature.

A hierarchical Bayes analysis for one-shot device testing experiment under the assumption of exponentiality

ABSTRACTThe article considers a two-stage hierarchical Bayes technique to analyze a dataset coming from a “one-shot” device testing experiment. The development is based on the assumption of exponential model for the lifetimes with failure rate regressed according to the Cox proportional hazards model. The Bayes implementation is done through a Gibbs–Metropolis hybridization scheme that easily entertains the missing data cases as well. Lastly, numerical illustration is provided based on a real data example on electro-explosive devices. The results show that the Bayesian method performs considerably well for such type of experiments.

Pin-pin ESD protection for electro-explosive device under severe human body ESD

Electrostatic discharge (ESD) may introduce huge damages to electro-explosive devices (EEDs). This paper studies the pin-pin ESD protection for EED under server human body ESD. We use the PSpice and MATLAB to simulate the ESD of EED protected with transient voltage suppressor (TVS), varistor, semiconductor arrester and capacitance. Moreover, we achieve the decay time, current waveforms, voltage waveforms and energy integration waveforms of the EED during the ESD, with different protections. Simulation results reveal that TVS succeeded in protecting bridgewire EED against the pin-pin ESD, while other three did not provide adequate protection. The pin-pin ESD experiments have been performed using the TVS and varistor. Experimental results show that, using the TVS protection, the EED is not firing under the severe 50kV ESD voltage. However, by using varistor protection, the ESD protection capability increases by more than 90%, while the protection capability only enhances by 3.1%. The response time of the TVS, i.e. 10−12s, is much faster than that of the varistor, i.e. 10−8s.

Statistical Process Control for Latent Quality Characteristics Using the Up-and-Down Test

ABSTRACTIn many applications, the quality characteristic of a product is continuous but unobservable, for example, the critical electric voltage of electro-explosive devices. It is often important to monitor a manufacturing process of a product with such latent quality characteristic. Existing approaches all involve specifying a fixed stimulus level and testing products under that level to collect a sequence of response outcomes (zeros or ones). Appropriate control charts are then applied to the collected binary data sequence. However, these approaches offer limited performance. Moreover, the collected dataset provides little information for troubleshooting when an out-of-control signal is triggered. To overcome these limitations, this article introduces the up-and-down test for collecting data and proposes a new control chart based on this test. Numerical studies show that the proposed chart is able to detect any shifts effectively and is robust in many situations. Finally, an example involving real manufacturing data is given to demonstrate the use of our proposed chart.