Papers by Keyword: Computer Aided Design (CAD)

Abstract: Globalisation is accelerating and with it rapid technological change has resulted in the environment being dramatically impacted by constant and significant change. The global job market requires excellent technical skills, so we must educate students for more sophisticated jobs. Today, engineers must be practical and creative, able to work with different people, be quick to solve problems and make critical business decisions, whilst being professional and ethical. Spatial visualisation skills play a significant role in engineering fields, particularly for mechanical engineering students whose fields rely heavily on visualisation. This paper presents the CAD course with computer graphics components that would help in enhancing students’ powers of visualisation using CAD applications.

Abstract: Series design is a systemic design process for enterprises, while computer virtual combination technology is vital for product series design. In the present paper, products series design is investigated; and based on it, various computer virtual combination technologies used in product series design are reviewed. The usage of computer virtual combination technology can save the cost of production, complete series design task and improve the efficiency and level of product series.

Abstract: There are two kinds of thinking strategy, which are vertical thinking and lateral thinking [1]. Nowadays, there are few computer-aided designs using design thinking strategy. Most computer aided designs combine the consumer's emotional and pattern matching. Base on this reason, this study's purpose is the application of design thinking strategy to computer-aided design, and use the Model of Two Paths which proposed by Tseng & Chang [2], and combined parametric modeling of derivatives design. The authors hope in the future, the computer systems can assist the designer in thinking. Currently, the study found the process of parametric modeling form generation that changes the spatial relation which is similar to Jumping thinking of lateral thinking. The shape evolution between different vocabulary is similar to Triggering thinking of lateral thinking [2].

Abstract: Systematic level design and optimization of a Radio Frequency (RF) receiver is a multi-dimensional problem and it is usually an arduous and experience-based work because of the trade-off between various system parameters. In the mean while, co-operated with Genetic Algorithm (GA) and local search, Memetic Algorithm (MA) gradually becomes popular to solve multi-dimensional optimization problems, and it can be an efficient method for computer-aided design of RF receivers. In this paper, the MA method was adopted to aid the design of a 5.8 GHz RF receiver front-end. The transfer function for the signal-to-noise ratio at the front-end output (SNRout) was first derived based on the gain, noise figure and inter-modulation product of each individual circuit component, and the transfer function was then used as the required fitness function for the MA method. The efficacy of the proposed method was validated by ADS simulations.

Abstract: In order to investigate the effect of the suture density on the mechanical properties of bioprosthetic heart valve, we establish the spherical leaflets models via computer aided design. Finite element analysis is used simulate the mechanical performance of bioprosthetic heart valve when leaflet is closed. The analysis results show that suture density has a significant effect to the stress state of valve, which may lead not only to different stress peak values, but also to different stress distributions. High or low density suture isn’t appropriate for long-term durability of the bioprosthetic heart valve. Suture density tests are needed to perform on the valves to find satisfactory suture density for better mechanical properties of the bioprosthetic heart valve.

Abstract: A quadratic trigonometric B-spline curve analogous to the standard quadratic uniform B-spline curve, with a shape parameter, is presented in this work. The shape of the proposed curve can be adjusted by altering the value of the shape parameter while the control polygon is kept unchanged. With the shape parameter, the quadratic trigonometric B-spline curve can be closer to given polygon than the standard quadratic uniform B-spline curve. The proposed curve can be used to accurately represent the ellipse.

Abstract: Computer aided design of the manufacturing technology for the fasteners is presented the paper. The particular objectives of the work were twofold. The first objective is evaluation of applicability of various materials for fasteners. Analysis of different technological variants is the second objective of the research. In the material part, bainitic steels are considered as an alternative for the commonly used carbon-manganese steels. This is a continuation of [1,2]. Possibility of elimination of the heat treatment was evaluated. Main features of the new generation of bainitic steels are discussed briefly in the paper. Rheological models for all steels investigated in the project were developed. The models were implemented into the finite element code for simulations of drawing and multi stage forging. Simulations of various variants of manufacturing chain were performed and the best alternative was selected. Criteria for the selection composed dimensional accuracy and tool life. Industrial trials were performed for the selected cycle and the efficiency of this cycle was evaluated. Finally, the optimization task was formulated. However, solution of the optimization problem is costly at this stage and improvement of the efficiency of the formulation will be the objective of further research. References 1. Kuziak R., Skóra M., Węglarczyk S., Paćko M., Pietrzyk M., Computer aided design of the manufacturing chain for fasteners, Computer Methods in Materials Science, 11, 2011, 243-250. 2. Kuziak R., Pidvysots’kyy V., Węglarczyk S., Pietrzyk M., Bainitic steels as alternative for conventional carbon-manganese steels in manufacturing of fasteners - simulation of production chain, Computer Methods in Materials Science, 11, 2011, 443 – 462.

Abstract: Objective To look for a suitable displacement range of acetabular medial wall following osteotomy by computer-aided design finite element analysis. Methods SolidWorks 2008 software was used to establish three-dimensional models of acetabular dysplasia pelvis. Acetabular medial wall displacement osteotomy was simulated to make acetabular medial wall bone displace from 2 mm bone contact to 7 mm bone contact in the pelvic cavity. One experimental group was set at 1 mm intervals, totally 10 experimental groups. The acetabulum in each group was split into four quadrants. The prosthesis acetabulum-bone interface in each group was analyzed by computer simulation contrast mechanics experiment. The Mises stress and shear stress values were measured between acetabular prosthesis and bone interface. Results In groups 1, 5, 6, 9 and 10, the Mises stress was unevenly distributed in posterior inferior, anterior superior and anterior inferior quadrants. In groups 2, 3, 4, 7 and 8, the Mises stress was evenly distributed in posterior inferior, anterior superior and anterior inferior quadrants. Of them, the stress was most even in the group 4. In groups 2, 3, 4, 7 and 8, the shear stress was evenly distributed in the above-mentioned three quadrants. The shear stress was lowest in the groups 7 and 8. These indicate that joint force in the acetabulum mainly focused in the posterior superior quadrant. With the displacement of acetabular cup, the contact area of acetabular cup and bone would gradually increase, which finally increased the Mises stress in the contact surface. However, shear stress decreased with displacement of acetabular medial wall. Conclusion the suitable displacement range of acetabular medial wall osteotomy is 1 mm away from the pelvic cavity and 1 mm complete embolism in the pelvic cavity. The optimal position was 1 mm complete embolism in the pelvic cavity.

Abstract: Objective To construct three-dimensional models of individualized femoral prosthesis by using computer-aided design and to verify whether individualized femoral prosthesis is superior to popular femoral prosthesis via simulating and contrasting mechanical study. Methods Two-dimensional images of fresh femurs were obtained by using total-length CT scanning and processed with computer edge recognition and three-dimensional contour extraction software to identify outer and inner contour of pulp cavity, extract contour data of pulp cavity and prosthesis, and construct three-dimensional models of femur and individualized femoral prosthesis. SolidWorks software was used to establish three-dimensional prosthetic models in common biological and bone cement types; moreover, bone-cement, biological, and individualized femoral prosthesis were replaced via simulating clinical surgery. Results Edge extracting was replaced by Canny operator, characterizing by stable running, credible outcome, and consistent with the primary request. Stress, femoral stress, interface stress, and primary micro-motion of individualized femoral prosthesis were significantly lower than biological and bone-cement femoral prosthesis (P Conclusion The computer-aided design is reliable to perform the assistant design of prosthesis; furthermore, biomechanical properties of the individualized femoral prosthesis are superior to those of popular femoral prosthesis.

Abstract: In recent years, the Computer Aided Design (CAD) technology is being utilized in the textile and clothing industry, thus simplifying the overall process and shortening the cycle from design to manufacturing. This greatly improves the manufacturing efficiency and also the garment quality. This paper presents the trend of 3D Garment CAD technology, analyzes the intelligent apparel CAD systems, including parametric design, Combination of artificial intelligence and CAD and the closely relationship between CAD and the Internet.