Applied Mechanics and Materials Vols. 752-753

Abstract: A kinematic optimization method of parallel manipulators is presented in this paper. A desired workspace for a parallel manipulator is usually an essential requirement in a practical application. Additionally, a good kinematic performance and/or a relatively small physical size would be of great significance. A dexterity index is utilized to measure the kinematic performance of parallel manipulators. A method to define the physical size of a parallel manipulator is introduced. The cost function is then formulated as a linear combination of a dexterity index and a physical size measurement. The Optimization Tool Box of MATLAB is applied to solve the optimization problem. Finally, a general Stewart-Gough platform is taken as an example to specify the design methodology.

Abstract: The paper deals with the determination of characteristic as dependence of the valve pressure drop on the flow rate, flow characteristic and cavitation conditions in case of water flow in the flow control valve. Emphasis is put on the utilization of simple, available relationships and measuring for identification of the basic valve coefficients, e.g. loss coefficient, flow rate coefficient and cavitation factor. These coefficients are used for designing of pipe circuits. In this paper there is defined methodology for determining those coefficients and is applied to the modified cone of flow control valve for verification the linear flow characteristic. It is necessary to consider the fact that in various countries the modifications of coefficients are preferred and it is therefore necessary to specify them.

Abstract: In the present study, an irrigation system with an adaptive control system and powered by solar photovoltaic panels was designed and implemented. The control circuit, which was produced by using dsPIC, performed the online processing of the data received from current-voltage sensors and liquid level measurements. Different from the other studies in the literature, in this study, the source from which the irrigation system is fed was determined based on the power produced by the panel. If the power produced by the panel was lower than the determined power value, the system was fed from the battery, if higher, directly from the panel. With this developed algorithm, it was aimed to keep the tank full and to extend the expected life of the battery in terms of the number of charges-discharges through preventing the unnecessary discharge of the battery at times when water was needed. As the result of this study, the system was operated at an optimum level without requiring any energy other than the photovoltaic panel.

Abstract: One degree of freedom (DOF) tele-hydraulic manipulation using force reflecting bilateral control will be investigated. The primary objective in the development of a simple one DOF experimental rig was to allow the investigation of different tele-control strategies prior to their implementation on the eight DOF tele-hydraulic excavator system. Because of the friction nonlinearity characteristic in hydraulic system, high steady state error and overshoot have occurred in the position response as a typical imperfect implementation of associated control dynamic. In this situation, there is a necessity to be able to effectively utilizing the intelligent friction compensated controller. This fuzzy compensator combined with fuzzy controller will be implemented to enhance the maneuverability performance. Experiments were carried out and the experimental results illustrated that the above compensated intelligent framework can improve the bilateral performance

Abstract: In view of the slowing expansion problem for the past harvesting robot’s electric push rod joint.This paper will adopt pneumatic draw stem instead of the original electric putter to improve the rapidity of servo system. Using VFW(Video for Windows) image acquisition system to access to the video buffer without generating the intermediate files,which can ensure high real-time performance. By monocular vision system to realize cylinder tracking control experiments for the fruit center position. Experiments verified the quickness and accuracy of the pneumatic servo positioning system.

Abstract: Nowadays, the car is cheaper than the former. As a result, consumers are increase buying new cars. It make the car parking service is experiencing problems about car information management. One problem is car theft. Because of driver can drive his car into and out of the parking is use only a car parking card for authentication. From the reasons discussed above, the car thief can occur. If owner of car leaving his car and forget parking card in his car or parking card was stolen. Car thieves were able to drive the car out of the parking is easy. This paper presents the concept and how to solve such problems. By apply of NFC technology on android phones and public key cryptography algorithm for use to open the gate of car parking automatically. The user must get the digital ticket from android application using his username and password and then drive his car into the car parking and touch his android phone on the NFC podium if authentic the gate will be open.

Abstract: Robot technology is important for students to be able to work in 21st century and to share technical knowhow. Learning robot technology is very difficult because the high costs of hardware equipment; it was used mainly in the hi-tech subject’s area such as military affairs, space, medicine, engineering, etc. With the improvements and developments of technology, Robot technology is now open for the general public’s use. In basic education, it is also more and more popular to use robot when teaching science, physics, technology, etc. Unfortunately, the robot equipment also still high costs. This project concentrates on the design and develops a low cost mobile robot kits as a teaching tool for education and research. In this project we developed a tool that will help students to understand technology based on mobile robotics technology and electronic engineering. The robot kit in this project was designed to create modular systems, considering assembly requirements of different types of objects as well as various user activities. Each module of the robot kit takes care of a core function required to operate automata. The modules help students build kinetic sculptures quickly and easily, eliminating the need for unsafe tasks such as soldering. Further, the features of this robot kit can be expanded to allow integration with programming modular and multimedia programming environment, making it possible to develop more creative automata for improve education and research forward.

Abstract: This paper presents design and application of foot modules in exoskeleton. Detecting the walking phase and intent is most important data for controlling the wearable exoskeleton. The zero moment point (ZMP) trajectory in the robot foot support area is significant criterion for a stability of the walk. The ZMP is calculated by measured force / torque data and Force / Torque sensor (F/T sensor) can measure that. But, the thick foot module is inconvenient to walking. For such a reason, most foot modules are developed using the film type sensors such as force sensing resistor (FSR), ground contact sensor such as tape switch and so on. In this paper, the foot modules equipped optimal design of 3-axis F/T sensor and ground contact sensor are presented and experimental application of detecting the walking phase using both sensors is introduced.

Abstract: In this paper, development of exoskeleton gripper targeted for FEM assembly process is described. This exoskeleton system is currently being under study for industry field application. The proposed gripper system is capable of robustly connecting bulky heavy-weighted FEM to exoskeleton robot system. In order to reduce the load on the exoskeleton, lightening method based on H-beam structure is used alongside with the usage of small actuators which was possible due to 4-bar linkage. Finally, performance of the developed gripper was validated through experiments.

Abstract: This paper presents a wavelet-based method of identification modal parameter and damage detection in a free vibration response. An algorithm for modal parameter identification and damage detection is purposed and complex Morlet wavelet is chosen as an analysis wavelet function. This paper only focuses on identification of natural frequencies of the structural system. The method utilizes both undamaged and damage experiment data of free vibration response of the truss structure system. Wavelet scalogram is utilizes for damage detection. The change of energy components for undamaged and damage structure is investigated from the plot of wavelet scalogram which corresponded to the detection of damage.