Papers by Keyword: Robust Design

Abstract: Considering the traditional safety factor method of reliability design can’t well reflect the uncertainty of loads, and error is obvious by using the tension of the wire rope represents the stress state of the hoist drum web plate. Established stress model of the dangerous section of the hoist drum web plate. Deduced reliability index and reliability by using stress & strength interference theory and perturbation method. Sensitivity analysis and robust optimal design was performed on this basis. The results show that the strain on the hoist drum web plate has a great influence on reliability of itself, and the reliability robust optimization design information can be obtained by using strain on web plate and reliability as optimization objectives. These not only provide the theoretical basis for the safety maintenance and design of the hoist, but also have the practical application value for reliable and efficient delivery of hoist.

Abstract: This paper presents relevant data for a robust design of thermoplastic products, as a support for optimization of product design. The study emphasis rules and recommendations related to wall thickness and corner design through which the developer could anticipate quality problems that might appear in the product’s lifetime, avoiding design features that might be difficult to be produced or produced with a cost that may not be feasible.

Abstract: The authors propose a method to assess the clarity of a design on working principle level. To do so, the Contact and Channel Model is used in an adapted form to differentiate elemental interfaces based on their geometry and function. This classification is used to derive a generic catalogue of elemental interfaces. A product can be represented through a combination of these interfaces and working structures in between. The design clarity can then be assessed through generic information stored in the catalogue. The authors propose a procedure model to implement this method and show exemplarily its applicability. Additionally, main design parameters that strongly affect a product’s behavior can be identified with help of the generic catalogue for every elemental interface. Finally, further steps regarding variability in design parameters are discussed.

Abstract: Systematic achievement of high productivity lapping entails conceiving of a robust working system, insensitive to the action of disturbing factors. The experiments described in this paper were aimed at configuring such a robust machining system in view of maximising productivity. The main purpose of the experiments was to identify an optimum combination of the values of the input quantities of the machining system, such as to achieve its robustness, that is rendering it insensitive to the action of noise factors.

Abstract: Uncertainty is inevitable in sheet metal metal forming process. Aleatory uncertainties in material properties, blank thickness and friction condition are inherent irreducible variabilities in sheetmetal forming. However, optimal design configurations which are obtained by conventional designoptimization methods are not always able to meet the desired targets due to the effect of uncertainties.In order to tackle this problem, a multi-objective robust design optimization (MORDO) applied forsheet metal draw bending process is introduced in this paper. In addition, since the MORDO of sheetmetal forming involves considering serveral conflicting criteria, a Pareto multiple objective criteriadecision-making approach based on capability indices is proposed.

Abstract: Fluctuations in material properties of the incoming steel for UOE forming process are widespread. According to the statistics, the fluctuation range of the yield strength of the same grade pipeline steel is around 80MPa. Robust optimization methods have been widely applied in sheet metal forming area. In this paper, experiments were conducted to investigate how a stochastic material behavior of noise factors affected UOE forming quality. Robust design models integrated with response surface method for UOE forming process were established to minimize impact of the variations and improve the qualified rate of UOE pipe ovality. Support vector machine in both classification and regression was adopted to map the relation between input process parameters and forming qualities. The deterministic and robust optimization results are presented and compared, demonstrating increased process robustness and decreased number of product rejects by application of the robust optimization approach.

Abstract: In view of robustness of objective function and constraints in robust design, the method of maximum variation analysis is adopted to improve the robust design. In this method, firstly, we analyses the effect of uncertain factors in design variables and design parameters on the objective function and constraints, then calculate maximum variations of objective function and constraints. A two-level optimum mathematical model is constructed by adding the maximum variations to the original constraints. Different solving methods are used to solve the model to study the influence to robustness. As a demonstration, we apply our robust optimization method to an engineering example, the design of a machine tool spindle. The results show that, compared with other methods, this method of HPSO(hybrid particle swarm optimization) algorithm is superior on solving efficiency and solving results, and the constraint robustness and the objective robustness completely satisfy the requirement, revealing that excellent solving method can improve robustness.

Abstract: In order to improve overall vehicle performance and decrease movement deviation caused by uncertainties from automobile chassis, a robust vehicle chassis model is built with steering system, suspension system and braking system. In the model, the length of the steering trapezoid arm, the bottom angle of trapezoid mechanism, inclination angle, caster, camber and toe-in are defined as controllable variables, and load, driving force, steering torque are defined as noise factors. The optimum objectives include the maximum turning angle error of steering mechanism, the maximum braking sideslip and the maximum swing angle of front wheel on bumpy road. Taguchi method is applied to solve the robust result for automobile chassis model. Compared that the variances of objective values are decreased with the same noise factors and the robustness of sub-systems of chassis is improved.

Abstract: In this paper, a dynamic robust design method is proposed to achieve a desirable dynamic performance in despite of parameter variation. Since it transforms the robustness of a dynamic system into the robustness of its characteristic variables, the complex dynamic robust design problem becomes a relatively simple static robust design problem. This greatly eases complex of this design. The effectiveness of the proposed method is further demonstrated by a comparison with the existing method on design of a practical hydraulic press machine.

Abstract: This paper introduces an innovative solution for devising a robust blasting plan that will present consistently good fragmentation performance under highly uncertain environments. The analysis will be carried out using complexity analysis tools, a model-free approach to complex systems which is particularly well suited to the problem of finding non-deterministic dependencies between multiple variables. The study is backed-up by data from over 2,000 blast records from Brazilian mines and identifies what are the critical aspects of the system and how to manage the blasting plan to reduce their impact on its performance.