Papers by Author: Yi Min Deng

Abstract: Computer-aided conceptual design of mechatronic products is becoming more and more important since it offers much convenience in design scheme retrieval and enhances the utilization of existing designs. One of the key technologies for computer-aided conceptual design is an efficient search algorithm for retrieving existing designs. As such, it’s necessary to find a feasible way to select the most suitable design out of a number of candidates for further development. By applying behavioral modeling method for representation of conceptual design, this paper proposes a node matching algorithm for searching behavioral model, together with a model similarity evaluation method. Based on these methods, a framework for computer-aided conceptual design is subsequently proposed. Finally, a case study is presented to illustrate the applicability of the proposed methodologies.

Abstract: Bond graphs are a domain-independent graphical description of dynamic behavior of physical systems. It is particularly suited for the concurrent design of multidisciplinary systems (including mechanical, electrical, hydraulic or pneumatic components). In this paper, we present our work on the conceptual design representation using bond graphs methodology to support the early stage of product development, especially the conceptual design of mechatronic products. Following the introduction of the fundamental concepts, a advanced notion so called activation is given to present signal systems (e.g. feedback controlled systems). Finally, a controlled DC motor driven system example is used to illustrate the process of model building and analysis of interdisciplinary systems based on bond graphs.

Abstract: Vibration isolation is a most widely used vibration protection method.The stiffness of vibration isolators in existing conventional type of vibration isolation system is usually of fixed value. This limits the system in exhibiting its vibration isolation effect in that, it has poor results for lower frequency vibration, especially for resonance frequency. Magneto-rheological elastomer is a new branch of Magneto-rheological materials. It’s an intelligent materials in that it’s shear modulus can be controlled by a magnetic field. It has wide application prospects in the vibration control area. This paper proposes using adjustable stiffness of magneto-rheological elastomer vibration isolation in vibration isolation system. By changing the current of vibration isolators coil to control the shear modulus of magneto-rheological elastomer, it can adjust the stiffness of the isolation system, making the system obtain wider vibration isolation frequency range. By exploying SimuLink software to analyze the vibration isolation system, it is found that such a design is effective and applicable.

Abstract: Injection moulding is an important manufacturing method for plastic parts. There are however many moulding quality defects caused by inappropriate setting of moulding process conditions, as well as the poorly designed plastic part geometry. Often, stiffeners are used in a plastic part to increase its strength. However, if the stiffeners are not designed properly, they will introduce one or more moulding quality problems, which in turn will worsen the part strength rather than increasing it. Although there have been quite a lot of researches on optimising moulding quality, it is often difficult to minimize multiple quality defects simultaneously. In this paper, we propose to employ flow uniformity as the optimisation objective to address this problem. A number of stiffener layout designs are evaluated in terms of this objective to determine the best design, where standard deviations of filling times and pressures at the extremities of the plastic part are used to measure the uniformity of flow. A simple case study is also presented to demonstrate the applicability of the proposed methodology.

Abstract: In this paper, Taguchi experimental design method is applied, and injection molding CAE simulation analysis is conducted. Influence factors of warpage of products are analyzed. According to the results of ranking, influence factors of warpag are the packing pressure, packing time, melt temperature and mold temperature. The packing pressure is the most important influence factor. To get the best level combination of various factors, mixed level orthogonal experimental design is applied to the optimization. Optimal levels of combination process parameters are obtained and the quality of injection products is greatly improved.

Abstract: By the combination of orthogonal experiments and moldflow simulation analysis, the warpage of a thin-wall injection molded parts is analyzed under the combined effects of multi-molding process parameters. By this method, it can gain the experiment data which can basically reflect the overall situation using fewer number of simulation analysis. In addition, the effects degree of different molding process parameters for warpage are researched, and the optimized parameter combination is obtained. It can avoid the one-sidedness of individual analysis of the various factors and solve the unreasonable appearance of process parameter settings. With the help of results, it can fasten the mold developing schedule, thus shorten the cycle of product development, and improve the quality of products and the competitive ability of enterprise.

Abstract: Design evaluation is necessary and important for conceptual design because it is often a must for designers to select a design concept from a number of candidates for further development. Assembly devices are usually product specific and there need extensive efforts in developing a feasible conceptual design solution satisfying a number of design constraints. To get a suitable evaluation method for assembly devices in the conceptual design phase, it’s necessary to apply Fuzzy mathematics in the evaluation method and the corresponding algorithm. This paper proposes a fuzzy index evaluation method for the conceptual design of assembly devices, where a number of evaluation indexes specific for assembly devices are proposed and organized into various levels for the evaluation algorithm. Finally, an evaluation software platform is presented, together with a simple design case study to illustrate the application of the proposed evaluation methodology.

Abstract: Tension control is widely used in industrial production. This paper gives one tension control method using MRF damper as the actuator. The principle of the tension generation is introduced. Through analysis and numerical simulation, the main influence factor of tension changing is obtained. The result of simulation shows that the influence factor of the tension includes the excitation electric current of the MRF damper, the radius of a wheel, rotate speed, the fluctuation of the rotate, etc. These factors present strongly nonlinearity. Through controlling the excitation electric current of MRF damper, the fluctuation of tension can be controlled to decrease.

Abstract: As a new type of smart materials, magnetorheological elastomer (MRE) has become a hot current research focus. However, the piezoresistivity and magnetoresistivity of MRE have not been well studied. In this paper, this was done by using a test rig developed by the authors. The experimental results showed that the conductivity of the MRE responded sensitively to the applied pressure, and a linear relationship between the resistivity of the MRE and the applied pressure can be observed within a certain range. Besides, the sensitivity of piezoresistivity is different among different ratios of metal content, and it becomes more obvious when using the nickel content. And, the magnetoresistivity of MRE is not obvious in a range of low magnetic field intensity, and there is also no hysteresis phenomenon about magnetoresistivity.

Abstract: Assembly devices are important in manufacturing systems. To study their conceptual design methodologies, it is necessary to investigate their behavioral process characteristics. In this paper, the behavioral processes exhibited by some assembly devices were studied, from which we discovered the so-called “phenyl-loop behaviors” with some unique characteristics. Some specific rules were subsequently proposed to help identify these behaviors, and their usefulness for conceptual design was also discussed. A structure-behavior database was set up based on existing assembly devices and a design platform was constructed for assembly devices design.