Applied Mechanics and Materials Vol. 459

Abstract: This paper studies the system modeling and mode-switch control for a novel 3-mode (serial/parallel/pure electric) range-extender electric vehicle (REEV). The REEV is modeled with low-order dynamics of 8 subsystems: the driving pattern, drivers behavior, lithium batteries, a spark-ignition engine, a traction motor, a generator, a 6-speed transmission, and a longitudinal vehicle dynamics. Dynamics of the REEV is the integration of above subsystems. To properly evaluate the system performance of the REEV, a rule-based mode-switch control rule is designed with 7 operation modes (System Ready, EV, Serial, Coast Down, Coast-Down Regen., Idle Regen., Parallel). By applying the control rules for the 3-mode REEV, the vehicle can properly operate. Simulation is conducted on the Matlab/Simulink platform. The results show that this study details the system dynamics of subsystems and the vehicle. Meanwhile the rule-based control strategy governs the subsystems well. The developed simulator can be utilized for specification designs of real vehicles and for vehicle control unit designs in the near future.

Abstract: Main purpose of this work is to show how easy and economics an ergonomic/comfort based approach, in re-design a manual assembly workplace, can be; authors, using a new comfort/ergonomic evaluation criterion, analyzed a workstation and identified the critical issues under ergonomic/comfort point of view and finally gave several guidelines to re-design the workplace, implementing minor modification, and improve work-safety, work-quality and productivity. The postural analysis was performed by non-invasive and especially inexpensive methods, based on cameras and video-recorder use and by photogrammetric analysis; DELMIA® DHM software has been used to perform all simulations; comfort analysis was performed by the software developed by researchers of Departments of Industrial Engineering of Salerno: CaMAN®. The test case is an automatic assembly machine that has been modeled and used for virtual postural analysis. Main results of this work can be found in a very good numerical/experimental correlation between acquired/simulated postures and real ones, and on the powerful use of an objective comfort evaluation method, based on biomechanics and posture analysis, for giving to designers the guidelines to re-design a workplace and a work-cycle. This kind of approach seemed to be very powerful in re-designing the work-place and in re-scheduling the work time-sheet because it allowed to improve an ergonomic corrective action with minor costs for company. Obtained results demonstrated the validity of re-design hypotheses through the increase of all comfort indexes and the improvement of workstation/operator productivity.

Abstract: In this research, deformation process of a thin ring plate with circular hole has been analyzed. Regarding the material characteristics and forming facilities, various forming in a blank with are possible Deep drawing without variation in central hole diameter and also by variation in hole diameter and Flanging when the outer diameter of blank is constant or variable. By taking into account the thickness variations, and work hardening, the forming of thin ring plate at plane stress condition has been considered. It is shown that the deformation procedure of each point in the blank can be describe by non-linear vector function of plasticity.

Abstract: The characteristics of a piezoelectric bimorph that fixed in one end (cantilever structure) have been well studied. The displacement of deformation and the force applying to the load are usually not easy to be both satisfied for many specific applications. In this paper, a new structure of a piezoelectric bimorphusing a hinged support and a pinned support (overhanging structure) has been analyzed and modeled to give flexibility in designing such a device to meet requirements of both the displacement and the force.

Abstract: With the increase in traffic density and speed of motor vehicles tire noise became an important area of research. A number of researchers have worked in the last decade to understand noise due to tires. It is important to identify different noise generation mechanisms that contribute to the tire noise and find a way to reduce it. In the present study, the noise generated by the acoustic cavity of the tire is taken into consideration. A non-linear finite element (FE) model using Abaqus has been developed for determining the acoustic pressure in the air cavity, when subjected to harmonic excitation. The influence of the inflation pressure and vehicle load on the tire acoustic cavity is studied for a passenger car radial tire (PCR) 175/70R13.

Abstract: The integrated transmission device of tank and armored vehicles is controlled by the electro-hydraulic control device, and the On-off shift solenoid valve is just the key component in it. As to models of different air gaps and voltages, through the magnetic circuit partitioning method and the finite element method, the relationship between design parameters and the electromagnetic force is got, and the reference ranges of voltage and gaps for steady electromagnetic force are also obtained from the results, which supply the theoretical basis for the design of structure of the solenoid valve.

Abstract: Piezoelectric bimorph has the advantages of small size, low power consumption and high operating frequency. Meanwhile, it has the short-comings of small displacement of deformation and weak driving force applying to the load. Piezoelectric bimorph actuators can replace the previous electromagnetic needle selector successfully by means of displacement magnifying mechanism and other auxiliary mechanism. An innovative piezoelectric jacquard selection mechanism has been designed in the paper.

Abstract: The surface roughness is an important indicator of precision. Generally, climb milling which is usually using in finish milling get better surface roughness and accuracy. In this paper, based on geometric analysis, the surface roughness of the conventional milling is better than the surface roughness of the climb. This result has been verified by experiment.

Abstract: As the resource advantage is gradually weakened, business situation of small and medium-sized enterprises (SMEs) engaged in medium and low-tech traditional industries is becoming more seriously. Industrial innovation and upgrading shall be conducted in order to achieve the sustainable development of traditional industries. Given the characteristic that medium and low-tech traditional enterprises rely on progressive innovation from the external organizations including the government, other enterprises and research institutes, etc., the enterprises should improve their strategic position in the industrial value chain, and change the business mode and growth pattern jointly from the aspects of technical innovation, system innovation, management innovation and cultural innovation, etc., to achieve the transformation from resource advantage to innovation advantage.

Abstract: A type of drive foot with displacement amplification was proposed based on analysis of the friction drive principle of the non-resonant linear piezoelectric motors. Firstly, the displacement amplification mechanism of the drive foot was carried on and the elliptical trajectory equation of the drive tip was deduced through the mechanism model of the drive foot. The optimization design of main structure parameters was conducted with finite element analysis software to analyze the influences of displacement amplification. The simulation results showed that the maximum magnification factor can be obtained when H(the thickness of flexible arm) is 0.8mm and θ (the flexible angle) is 12°. A linear piezoelectric motor prototype was designed and fabricated, the experimental results indicated that this kind of motor can run steadily in a wide range (the operation bandwidth is beyond 1kHz) and that the thrust can be 0.35N and the maximum velocity can be 2.5mm/s when the operation frequency is 4kHz and the operation voltage is 90V.