Applied Mechanics and Materials Vol. 440

Abstract: Weight reduction and the structural strengthening of frameworks have always been of great interest for automobile and bicycle manufacturers. In order to achieve this goal, manufacturers have always been looking for new materials and their corresponding processing technology. This paper focuses on investigating the most suitable forming-control path pattern for manufacturing magnesium-based alloy quadrilateral tubular components using the tube-hydroforming (THF) process for framework components. Conventionally, there are three usual patterns of forming-control path. Through numerical simulation, it was found that forming-control path C provided the best profile results. The simulation results were also verified by physical THF experiments which were carried out at around 270oC to fabricate the quadrilateral tubular component. A good agreement between simulation and experimental result was achieved, indicating that employing forming-control path C in the actual THF process provides the best forming results, minimizing the occurrence of wrinkling. The formability of such high value-added hydroformed tubular components can be predicted. Trial-and-error during the design stage can be avoided, which contributes to lower production costs.

Abstract: According to the problem of cylindrical helical compression springs deformation and fracture in the process of using. come up with a Solution that use conical helical spring instead of it, validate the improvement measure with relevant simulation and test analysis, draw a conclusion that the working performance of conical helical spring is better than the cylinder, this paper has some guiding effect on the selection of Annular valve spring.

Abstract: When rolling thread shaft in cross wedge rolling, forming quality of thread is affected by many process parameters such as the thread helix angle, which is a special and complex parameter. However, there is few study of the effect of the thread helix angle on thread shaft forming. In this paper how thread helix angle affects axial metal flow was analyzed from the perspective of rolling force and the forming process of thread shaft was simulated with different helix angles by the deform-3D software. Through the measurement of the point coordinates, the effect of the helix angle on the axial metal flow of rolled pieces was analyzed. Finally, the conclusion was obtained that helix angle causes the asymmetry of axial metal flow with small difference values for asymmetry and the axial metal flow of rolled pieces increases as the helix angle increases. The rolling thread segment can be ensured in the middle of rolled pieces by moving the blank a suitable distance in the reverse direction of the axial flow direction.

Abstract: It is often needed to define the velocity and acceleration of the body or some point of mechanism, if the input parameters of driver are known. As one of the most commonly used mechanisms in manufacturing or real practice can be considered the slotted-link mechanism. This mechanism is the part of the various machines and it has some special configurations created by making link infinite in length. It is often used to transform rotary motion into linear motion. The article deals with the computer aid of mechanism behaviour, specifically there are compared two approaches to the kinematic analysis of mechanism, the possibility to generate curve trajectory of selected point of mechanism or to make its motion envelope. The solution is presented on the mechanism usually used for the sliding feed of the packages in real practice.

Abstract: The article deals with the designing and simulation of technological process. Its modelling in virtual 3D environment was realized by means of selected software Sketch Up Pro. Computer aid is one of the tools which enable to visualize workshop environment, the motion of all its objects and so to predict the behaviour of individual technical or technological equipments in the real production process. The collisions and other problems can be eliminated, so consequently the quality and production efficiency of existing manufacturing process can be improved. The article is concerned to the virtual design of gears production. There are described some aspects of this technological process, suggested technical devices and the individual steps needed for successful manufacturing start-up.

Abstract: Some criteria for designing an ergonomic mouse for professional computer users via scenario-based design are presented in order to decrease Work-Related Musculoskeletal Disorders (WMSDs) especially in upper limbs. Library research studies performed based on 5W-H approach extremely tend to medical, ergonomics and functional affairs. Since this study was user-centered design (interaction design), practical research studies performed for better comprehension of users needs by making use of questionnaire, interview and observation procedures in three field of design: ergonomics, functional and aesthetics. First, target group divided into three categories by using AHP method: A-users who work professionally with design, graphic and animation softwares; B-users who work professionally or unprofessionally with other softwares; and C-users who work professionally with engineering softwares. Then, 56 questionnaires are presented to this group and also they interviewed and 15 ones observed during interaction with computer mouse. Finally, 23 design criteria achieved and final idea designed based on these criteria. The most important notes that considered in final design are neutral position of wrist, ulnar deviation prevention and preventing from static and powerful grips.

Abstract: As medical sciences have progressed and new medicines discovered, the use of more precise and optimal methods of injecting medicinal fluids and more specifically injection in longer time spans has become evident. Peristaltic pump is used in almost all medical supervisions which require precision application of medicines more common in hospitals, elderly housings, clinics and private home patient care taking. This pump may be used for slow liquid medicine injections for the purpose of pain reduction in a wide spectrum of inpatient treatments as well as for tube feeding in patients incapable of eating solid foods. Due to the vital importance of peristaltic pump applications in medical institutions and in respect to previous design efforts done on this machine, the objective of this research is designing multipurpose model of it and preparing necessary plans for its industrial manufacturing using interaction design. In order to obtain the hospital nurses opinions as target population about the application and desired characteristics of a peristaltic pump, a survey research method (questionnaire, personal interview and observation) are applied. Finally, proposed plan for a novel product consists of a pump body taking into consideration the functional; ergonomics as well as aesthetics aspects are represented.

Abstract: Friction of screw thread connection will cause temperature rise while projectile unloading, Too high temperature which would cause the combustion will result in significant safety issues, so the temperature field of screw thread connection must be analyzed when the projectile unloading. But friction is a complex process, how to simulate the temperature change accurately is the key link of the whole analysis. In this paper, friction of the screw thread surface in the process of unloading is simulated based on thermal analysis function of ANSYS. According to temperature distribution of the screw thread surface, the highest temperature and position of the highest temperature point is determined. The relationship between temperature and different speed is analyzed, which can provide a theory basis for safely unloading.

Abstract: The physical-chemical properties of rubber products in sport equipment such as elasticity,tolerance,endurance,hardness etc not only are related to the factors of formulation in material and structure size etc, but also mainly depend on the control effect of forming process in vulcanizing phase. Aimed at the puzzle of being difficult to control resulted from uncertainty in vulcanizing phase, the paper proposed a sort of intelligence fusion control strategy. In this paper, it summed the control puzzle in complex vulcanizing phase, researched on the cybernetics characteristic, explored the control strategy of complex process with uncertainty, proposed a sort of intelligence fusion control strategy, and constructed the control model and algorithm. The simulation and engineering verification demonstrated that it could be stronger in robustness, and higher in control precision compared with PID controller. The research result shows that the proposed control strategy is feasible and effective.

Abstract: Through the analysis of the research status and application characteristics of the pipeline robot, a design of pipeline and slot multi-function robot is presented. The robot adopts pneumatic power systems and peristaltic walk way. The robot can move not only in reducing pipe to clean or detect, but also between the slot to rescue or transfer goods according to computer instructions. The system is operated by slave control unit and controlled by PC through an auxiliary rope, so the robot has advantages about real-time detection of the work state, strong driving force, easy maintenance and fault recovery, low cost and so on.