Applied Mechanics and Materials Vol. 590

Abstract: The sensitivity analysis of performance for flexible pavement can be used to study the influence of every parameters, which can help optimization design and performance evaluation of the pavement structure. In this research, three asphalt layers and four asphalt layers were selected to study the sensitivity of traffic and material parameters based on MEPDG method. Some computer aided engineering simulation techniques, such as the Latin hypercube sampling (LHS) technique and the multiple regression analysis are used as auxiliary means. The single factorial sensitivity analysis method was used to calculate the sensitivity of traffic and material parameters and to validate the result of sensitivity analysis in multiple regression process based on MEPDG. The result shows that, about traffic parameters, Two-way AADT, Dual tire spacing and Vehicle operational speed are more significant than other parameters. The largest effects on rutting are due to Air Void--2, Air Void--1, Poisson' Ratio--1 and Poisson' Ratio--2. However, it is different on cracking, where the largest effects are due to Air Void--1, Poisson' Ratio--1, and Efficient Binder Content--1.

Abstract: The practical requirements of the project the nozzle entrance temperature is high, the gas specific heat ratio varies greatly, so it must consider the specific heat ratio change impact on two-dimensional nozzle contour design. Divided into consideration specific heat ratio change and not consider two kinds of scheme design of 1.4Ma nozzle profile and build the model using the arc line method, numerical simulation is carried out through the CFD software Fluent, analysis of two kinds of design scheme comparison. The results show that, in the supersonic nozzle at low Maher numbers, two schemes of nozzle design profile similarity, parameters change little flow tube, export the Maher number and the flow quality can meet the design requirements, proof of specific heat ratio has little effect on the design results in the design of the nozzle under the condition of low Maher number.

Abstract: This paper describes the process of designing the mechanical part of a robotic system able to travel autonomously on power transmission lines, to inspect them. Such a robot has to do more than just rolling on the power transmission line. Obstacles are plenty on these hundreds of kilometers long cables, and towers are regularly standing along the line. Solutions to solve this problem have already been proposed by many researchers, but none of them entirely managed to achieve a complete solution of the problem. As a part of the total project, this work does not have for ambition to solve the entire problem, but to bring new elements of solutions. First is performed a revision of existing robots. After, is presented the robot characteristics and finally a first prototype of the robot is presented.

Abstract: This article aims to find out the efficient design method of intelligent interaction in industrial design. It analyzes its significant impact on industrial design, and looks into three main forms of intelligent interactive design. Through the discussion and comparison of users’ choice based on their behavior characteristics and their selection of the operating signal source, this paper gets a conclusion that the intelligent interactive design goes ahead along with the acceptance of users’ material and spiritual recognition and cooperation, and combines with the ergonomic and product structure knowledge to reach its efficient design method goal for industrial design.

Abstract: Wheelchairs are an indispensable transportation tool for the aged and for the disabled. Tips and falls are common accidents to current wheelchairs, suggesting wheelchair safety is imperfect. This study thus proposed an anti-tip concept design to improve manual wheelchair safety. The anti-tip wheelchair was ergonomically designed with the following features: (1) diamond pattern wheel alignment enables users to adjust rear-wheel chamber angle and extend the front and rear casters forward and backward respectively to prevent tipping by increasing the base area; (2) adjustable wheel mechanism for indoor and outdoor uses; (3) collinear alignment of the rear-wheel axle and the center of mass in the sagittal plane reduces push frequency and enhances push power; (4) a spring-driven rear caster compression mechanism aids passing over obstacles on the ground; and (5) height adjustable neck rest provides comfort support.

Abstract: WHO reports the world population is rapidly ageing. The number of people aged 60 years and over is expected to 2 billion. The muscle strength of the elderly was decreased the ability of movement was therefore limited. Designing a facility to facilitate assist elderly for transportation is important and required. This study aims to propose a leverage wheelchair for the elderly. A serial design procedure including concept design, mechanism design, ergonomic design, and appearance design were performed in the study to create the new product. Finally, a leverage wheelchair was then proposed with following features: (1) the appearance of the leverage wheelchair demonstrated a powerful and friendly image; (2) the power transfer mechanism is designed with a power transfer mechanism which enables user to move wheelchair with a small strength; (3) the cover of the power transfer mechanism is an protection and visual element for the wheelchair; (4) the handlebar was designed with a power-saving mechanism to facilitate the elderly to move the wheelchair. It is also designed to assist user to stand up easily, (5) the handlebar was design at a position where the user can operate easily and comfortably; (6) a control button was deigned to control wheelchair going forward or backward; (7) the push handle was designed for fitting the hand of the caregiver. The results of design works, the methods and procedure used in this study can be a reference for product design and development.

Abstract: According to the report of WHO, the world population is rapidly ageing. Coming to the year of 2050, the proportion of the older population over 60 years will be 22%. The number of people aged 60 years and over is expected to 2 billion. Standing up movement is an important activity for human, because most activities in daily life are performed with standing position. The elderly with difficulty in standing up movement will strongly affect their daily activities. This study aims to propose an apparatus to assist standing up from sitting. A series of design methods and procedure including concept design, mechanism design, ergonomic design, and appearance design were performed in the study. Finally, an apparatus design was proposed with following features: (1) the appearance of the assistive device designed with an image of appetence; (2) a power-saving mechanism was designed which enabled users to elevate themselves easily; (3) a slow elevating mechanism was designed which enabled users to stand up slowly; (4) the of handlebar was operated at a position at elbow height which enabled users to exert maximum push force; (5) when the device elevated, the users enable to push maximum force to standing up; and (6) when the user was seated or absent for a long period, the handlebar can be located at a noninterference place. The results of design and the methods and procedure used in this study can be a reference for the product design.

Abstract: When doing mechanical design, in order to ensure proper function of crucial parts, not only should the structure be well-designed, but also should strength and rigidity meet the requirement. However, traditional checking methods contain many procedures and are complicated, which makes mistakes easy to occur; and once it goes wrong in any procedure, the design must be carried out again from the start. So, much time and energy of the designers are wasted on checking, and they can’t focus on the design itself. AutoCAD Mechanical is a version of AutoCAD designed specially for mechanical professionals. It contains all the graphic drawing function of AutoCAD, and with its shaft design function, strength, torsion angle and rigidity checks can be carried out easily. Compared with traditional design method, it has the advantage of simpler operation and full-automatic structuralization. Somehow it is not used by many. Hence, with many years of experiences, the author analyses the design and calculation of shaft parts with AutoCAD Mechanical, in hope to help designers release repeated inefficient work, and raise the quality and efficiency of design. Foreword During mechanical design, in order to ensure proper functions and mechanical properties of parts such as shaft, strength check must be carried out. For crucial parts, rigidity and torsion angle checks are also necessary, to ensure the deformations are within allowable range, so as to make sure that the shaft can bear the loads and work properly. However, strength check requires massive knowledge and procedures, as well as complicated calculations, which makes it easy to go wrong. During the calculation, the values of various coefficients should be considered, and once taken improperly, it may lead to vague calculation results, and then the procedure must be carried out again. Undoubtedly, this method makes design efficiency low, and designers must spend much time and concentrations on repeated work, instead of focusing on renovation. However, checking strength of shaft with AutoCAD Mechanical can make the procedures simple and accurate, and raise the efficiency.

Abstract: Nowadays, the instant beverage has been a necessary for daily life. The chain stores of instant beverages are popular in recent years. The sales volume per year of instant beverages reaches to US$ 133 million in Taiwan. The reason of the prosperity of the beverages in Taiwan is that the beverages are able to be made according to custom’s needs. So that the beverage can be fit to the custom’s favorite and habit. Therefore, for the considerations of safety, sanitary, and consistent quality, an instant beverage maker is needed to be developed. This study applied a systematical design procedure to develop and design the beverage maker. Firstly, marketing and technical survey, user needs and ergonomic analysis, and materials and methods of beverages investigation are conducted to determine the design requirements and specification of the product. Secondly, a series of design processes are proceed to develop the product, among them are concept design, mechanism design, ergonomic design, appearance design, 3D modeling and model making and testing. Finally, a new product is designed with the following features: (1) the instant beverage can be produced to match the favorite and habit of the customs; (2) the beverage can be produced with a high quality and stability, (3) the beverage maker with automatic processing functions thus saving manpower and manufacturing time; (4) this product with a friendly interface thus facilitating users to operate and clean it easily; and (5) the appearance is appealed and has high-tech and professional image. The newly designed product can be sold in Taiwan and the international markets. The design process and results of the study can be used a reference for product design and development.

Abstract: To efficiently construct the topology of STL file is one of the key factors to improve efficiency of slicing algorithm. In this paper a topology construction algorithm based on triangle facets ring and a rapid slicing algorithm are developed, in which the flag variables are defined to reduce search range when slicing. Then the algorithm can reduce the times of traversing and sorting for the triangle facets and the times of calculation intersection in the slicing processes, and it also can simplify the process of constructing the slice contour so as to improve the efficiency of the slicing algorithm.