Reliability Robust Design Research Articles

Interval Uncertainty Quantification for the Dynamics of Multibody Systems Combing Bivariate Chebyshev Polynomials with Local Mean Decomposition

Interval quantification for multibody systems can provide an accurate dynamic prediction and a robust reliability design. In order to achieve a robust numerical model, multiple interval uncertain parameters should be considered in the uncertainty propagation of multibody systems. The response bounds obtained by the bivariate Chebyshev method (BCM) present an intensive deterioration with the increase of time history in the interval dynamic analysis. To circumvent this problem, a novel method that combines the bivariate Chebyshev polynomial and local mean decomposition (BC-LMD) is proposed in this paper. First, the multicomponent response of the system was decomposed into the sum of several mono-component responses and a residual response, and the corresponding amplitude and phase of the mono-component were obtained. Then, the bivariate function decomposition was performed on the multi-dimensional amplitude, phase, and residual to transform a high-dimensional problem into several one-dimensional and two-dimensional problems. Subsequently, a low order Chebyshev polynomial can be used to construct surrogate models for the multi-dimensional amplitude, phase, and residual responses. Then, the entire coupling surrogate model of the system can be established, and the response bounds of the system can be enveloped. Illustrative examples of a slider-crank mechanism and a double pendulum are presented to demonstrate the effectiveness of the proposed method. The numerical results indicate that, compared to the BCM, BC-LMD can present a tight envelope in the long time-dependent dynamic analysis under multiple interval parameters.

빅데이터 기반 시스템의 사용 패턴을 고려한 신뢰도 최적 설계 프레임워크

Purpose: This study presents a framework for the robust reliability design of a multi-functional system by considering various usage patterns of an existing system.<BR>Methods: The framework consists of four stages: 1) identifying the critical component in a multi-functional system, 2) collecting and analyzing data from users, 3) designing for optimal system reliability, and 4) validating system reliability in various operating environments. Moreover, the framework includes failure mode and effects analysis (FMEA), big data on system usage, the redundancy allocation problem (RAP), and the genetic algorithm (GA).<BR>Conclusion: By using a framework that considers the usage pattern of a system, it was possible to achieve target reliability and a robust design for various usage patterns. Compared to the usage patterns experienced by many users in the existing structure, it was confirmed that most users experienced few (or no) failures. In addition, the framework was robust during the verification stage.

Reliability-oriented optimization of aluminum electrolytic capacitor considering uncertain mission profile

Aluminum electrolytic capacitors (Al-Caps) are responsible for the failure of power converters on a considerable scale. To optimize the lifetime of Al-Caps under various operation conditions, this paper proposes a reliability-oriented optimization method for aluminum electrolytic capacitors (Al-Caps), which considers uncertainties of mission profiles. The Al-Cap in LED driver is taken as a case study to illustrate the optimization procedure. The uncertainties of mission profile (i.e. ambient temperature and operating time) are modelled by kernel density estimation according to historical weather data. Then, the temperature stresses of Al-Cap under various operating conditions are analyzed by both thermal simulation and experiments. Taking uncertainties of mission profile into account, Monte Carlo simulation is carried out to calculate the B10 lifetime distribution of Al-Caps. Afterwards, the reliability-oriented optimization formulation is established by integrating both the average value and standard deviation of mission profile-based lifetime distributions. Finally, the particle swarm algorithm is applied to obtain an optimal solution of Al-Cap design. The proposed method could offer a robust reliability design of Al-Cap in LED driver, which improves both reliability and robustness at the same time.

Reliability-Based Robust Multi-Objective Optimization of Friction Stir Welding Lap Joint AA1100 Plates

The current paper presents a robust optimum design of friction stir welding (FSW) lap joint AA1100 aluminum alloy sheets using Monte Carlo simulation, NSGA-II and neural network. First, to find the relation between the inputs and outputs a perceptron neural network model was obtained. In this way, results of thirty friction stir welding tests are used for training and testing the neural network. Using such obtained neural network model, for the reliability robust design of the FSW, a multi-objective genetic algorithm is employed. In this way, the statistical moments of the forces, temperature, strength, elongation, micro-hardness of welded zone, grain size and welded zone thickness are considered as the conflicting objectives. The optimization process was followed by multi criteria decision making process, NIP and TOPSIS, to propose optimum points for each of the pin profiles. It is represented that some beneficial design principles are involved in FSW which were discovered by the proposed optimization process.

Graphic illustration for mechanical reliability design (2): theory and method

In this paper, the connotation and an extension of the mechanical reliability design theory and method are presented via charts and texts. The abstruse mechanical reliability theories and methods are illustrated intuitively and scientifically via easy-to-understand language and simple and clear illustrations. Topics such as mechanical strength design, mechanical reliability design, dynamic and gradual reliability design, reliability optimization design, reliability sensitivity design and reliability robust design are covered to help the readers understand the wonder and practicality of mechanical reliability engineering. Diagrams of reliability design, dynamic and gradual reliability theory and technology, reliability optimization design, reliability sensitivity design and reliability robust design are illustrated for the first time. Additionally, the relationship between mechanical product reliability design and conventional safety factor design is elaborated in a table. This paper provides a solid mechanical reliability engineering foundation for design, manufacturing, usage and evaluation of mechanical products.

Reliability Evaluation and Robust Design of a Sensor in an Entire Roller-Embedded Shapemeter.

The intermittence of the shape detection signal associated with an entire roller-embedded shapemeter roll, used in a seven-pass cold reversible rolling process, is considered. A transient interference at the sensor top surface and the distance between the sensor top surface and the roll outer surface are developed, and a sensor reliability evaluation model is derived. The reliability of the sensor is evaluated via the random perturbation method, and the reliability sensitivity of design variables is proposed. The analysis reveals that the reliability is smallest in the third rolling pass. Of the design variables considered, the initial interference exhibits the largest reliability sensitivity and has the greatest influence on the sensor reliability. A reliability robust design model of the initial interference is therefore developed. A new shapemeter roll is fabricated and tested in a 1050 reversible cold rolling mill. The test results are consistent with the theoretical results, thereby validating the proposed model. The selection of an appropriate initial interference provides an important means of overcoming the adverse effects associated with the thermal deformation of sensor contact surfaces.

Reliability robust design of tracked vehicle torque axis with multiple failure modes

Reliability robust design of tracked vehicle torque axis with multiple failure modes

Robust Reliability Design of Banjo Flange Based on Bayesian Theory

The perturbation method, bayesian statistics theory, the reliability optimization design, the reliability sensitivity technique and robust design are employed to present a practical and effective approach for the robust reliability design of the Banjo flange under incomplete information. The theoretical formulae of robust reliability design for the Banjo flange under incomplete information are obtained. The respective program can be used to obtain the robust reliability design parameters of the Banjo flange under incomplete information accurately and quickly.

The Fuzzy Reliability Robust Design Based on MATLAB

In order to rationalize the design of the worm-drive, the fuzzy reliability design method and robust design method were fully applied to develop the new model for fuzzy reliability optimization design of worm-drive with the minimum weight, minimum sliding-velocity, and minimum sensitivity as the objective function. The fuzzy optimization design result of the worm-drive was obtained by compiling MATLAB procedure. Compared with traditional design methods，the center distance was reduced by 33.3％, the sliding speed is reduced by 10.6%.The life of the worm-drive was raised by11.5％,and the wear quantity of the worm-drive was decreased by 0.1％after 100 hours' running.

Frequency Reliability Robust Optimization for Rotor System

The material properties and geometry of rotor system are random parameters because of the manufacturing environment, manufacturing and installation errors and other factors. Based on the reliability design theory, the reliability sensitivity technique and the robust design method, the frequency reliability robust optimization method of rotor system is extensively discussed. The frequency reliability sensitivity is added to the reliability-based optimization design model of rotor system. The frequency reliability robust design is described as a multi-objection optimization. The method presented provided the theoretic basis for the reliability robust design of the rotor system. A numerical example demonstrated that the proposed method is effective.

The Robust Reliability Optimization of Steering Mechanism for Trucks Based on Non-Probabilistic Interval Model

In the optimization design for steering mechanism of trucks, considering the impact of controllable factors and noise factors, based on the reliability optimization theory, the stable reliability sensitivity method and the robust design method, the robust reliability design for steering mechanism of trucks is extensively discussed. Compared with the conventional probabilistic reliability optimization approach, the proposed method does not require a presumed probability distribution of the uncertain parameters and only the bounds or ranges of their variations are required. The movement precision is chosen as objective function and kingpins distance, axle base, the bottom angle of trapezoid and the arm length are chosen as design variables.

Robust Reliability Design for Networked Control Systems Based on Information Scheduling

This document explains and demonstrates how to prepare your camera-ready manuscript for Trans Tech Publications. The best is to read these instructions and follow the outline of this text. The text area for your manuscript must be 17 cm wide and 25 cm high (6.7 and 9.8 inches, resp.). Do not place any text outside this area. Use good quality, white paper of approximately 21 x 29 cm or 8 x 11 inches (please do not change the document setting from A4 to letter). Your manuscript will be reduced by approximately 20% by the publisher. Please keep this in mind when designing your figures and tables etc.Networked Control Systems (NCS) are systems with at least one loop closed through data networks. The existence of real-time network in the feedback control loop makes it more complex to analyze and design the NCS. In this paper, the networked control systems with network-induced delay, parameters uncertainty and packet loss which are induced by the limited bandwidth of communication networks is modeled, consider the sensors that can’t send information to controller and the actuators that can’t receive information calculated and sent by the controller, the integrity design of the networked control system with sensors failures and actuators failures is analyzed based on information scheduling and robust fault-tolerant control theory. Sufficient conditions, based on Lyapunov function method, are established in terms of linear matrix inequalities (LMIs). When these LMIs are feasible, the explicit expression of the controller can also be characterized. After detailed theoretical analysis, the simulation results is provided, which further demonstrated the proposed scheme.

Robust Reliability Design for Networked Control Systems Based on State Observers

Networked control systems with network-induced delay, packet loss and parameters uncertainty is modeled in this paper, consider the sensors that can’t send information to controller and the actuators that can’t receive information calculated and sent by the controller, the integrity design of the networked control system with sensors failures and actuators failures is analyzed based on robust fault-tolerant control theory. Parametric expression of controller is given based on feasible solution of linear matrix inequality. After detailed theoretical analysis, the simulation results is provided, which further demonstrated the proposed scheme.

An Approach of Robust Reliability Design for Structure System with Multiple Failure Modes

Based on the reliability theory, the probability perturbation technique, the reliability sensitivity technique and robust design were employed to discuss the reliability-based robust optimization problem of structure system with multiple failure modes. By means of the probability network evaluation technique (PNET), the representative failure modes of structure system were defined. Then, the reliability and the reliability sensitivity of the system were obtained. By integrating the reliability sensitivity into the reliability-based optimization design model, the robust reliability design of structure system was discussed. According to the numerical results, the method proposed is validated to be practical and effective.

Robust reliability design of a nuclear system by multiple objective evolutionary optimisation

This paper proposes the use of multiple objective evolutionary algorithms and interval arithmetic for the robust reliability design of complex systems such as those employed in nuclear engineering. A numerical example, relative to the residual heat removal system of a nuclear power plant, is presented to illustrate the benefits of the approach.

An approach of robust reliability design for mechanical components

The reliability-based optimization, the reliability sensitivity technique, and the robust design are employed to present a practical and effective approach of robust reliability design for mechanical components on the condition of known probabilistic characteristics of original random variables. The theoretical formula of robust reliability design for mechanical components is obtained. The respective program can be used to obtain the robust reliability design parameters accurately and quickly. According to the numerical results, the method proposed is a convenient and practical robust reliability design method.

Robust Reliability Design of Banjo Flange With Arbitrary Distribution Parameters

The perturbation method, the Edgeworth series, the reliability-based optimization, the reliability sensitivity technique, and the robust design are employed to present a practical and effective approach for the robust reliability design of the Banjo flange with arbitrary distribution parameters on the condition of known first four moments of original random variables. The theoretical formulas of robust reliability design for the Banjo flange with arbitrary distribution parameters are obtained. The respective program can be used to obtain the robust reliability design parameters of the Banjo flange with arbitrary distribution parameters accurately and quickly.

Robust reliability design using environmental stress testing

This paper presents a strategy for improving reliability by using a robust design method. In this approach, reliability is related to performance degradation and several reliability models are developed to address performance degradation. This robust design strategy integrates orthogonal array experiments with environmental stress testing. Its goal is to select optimal levels of design parameters such that the product performance will be less sensitive to environmental stresses and thus more reliable. This method is applied to the design of an IC wire-bonding process and a comparison shows that the products produced with optimum design parameters are more robust and reliable under environmental stresses. Copyright © 1998 John Wiley & Sons, Ltd.

Robust reliability design using environmental stress testing

Robust reliability design using environmental stress testing