Applied Mechanics and Materials Vols. 284-287

Abstract: The development of wireless communication and electronic technology leads to wireless sensor networks in various fields. Wireless sensor networks can exchange the data that generated from near environment field observation between other sensor nodes. Generally, Wireless sensor networks consist of multi sensor nodes and one or more sink nodes The sensor sensing data that nodes detected transmit from sensor networks to base station and deliver to users through internet. However sensor networks are restricted in the aspects of communication, processing data and energy consumption. Because of the low capacity batteries with devices of sensor networks, it is important to increase the lifespan operation life of sensor nodes by using energy efficiently. In this kind of sensor nodes, the energy consumption for message sending and receiving is very important for the maintenance of sensor nodes. In the existing static routing method, it consumes more energy for the maintenance of sensor network than dynamic routing method because data transmits repeatedly when the sensor data begin to spread. In this study, based on the difference in the cycle of information gathering in accordance with the characteristic of the sensor in sensor network and the cycle of demands from the sink in accordance with the characteristic of application layer, dynamic routing of wireless sensor network is proposed which actively responds to its various needs.

Abstract: In order to solve outdoor positioning problems, a global positioning system (GPS) seems to be the best solution. However, GPS is unable to accurately and precisely locate objects or humans indoors. Thus, in this paper, we propose an efficient method for localization and position estimation for mobile robot navigation using passive radio-frequency identification (RFID). With our method, it is possible to accurately locate autonomous entities such as robots and people within a defined area. In simulations, we use PID controllers to increase the efficiency of captured RFID tags. Experiment results show that the number of captured RFID tags using our proposed method is greater than that of the fixed power level method.

Abstract: This paper aims to present the design, fabrication and test of a novel piezoelectrically actuated, check valve embedded micropump having the advantages of miniature size, light weight and low power consumption. The micropump consists of a piezoelectric actuator, a stainless steel chamber layer with membrane, two stainless steel channel layers with two valve seats, and a nickel check valve layer with two bridge-type check valves. The check valve layer was fabricated by nickel electroforming process on a stainless steel substrate. The chamber and the channel layer were made of the stainless steel manufactured using the lithography and etching process based on MEMS fabrication technology. The effects of check valve thickness, operating frequency and back pressure on the flow rate of the micropump are investigated. The micropump with check valve 20 μm in thickness obtained higher output values under the sinusoidal waveform of 120 Vpp and 160 Hz. The maximum flow rate and backpressure are 1.82 ml/min and 32 kPa, respectively.

Abstract: This paper describes the development of a low cost, compact and portable automated piano player CantaPlayer. The system accepts digital MIDI (Musical Instrument Digital Interface) files as input and develops pushing actions against piano keys which in turn produces sounds of notes. CantaPlayer uses Pure Data, an audio processing software to parse MIDI files and serve as user interfaces. The parsed information will be sent to Arduino, an open source microcontroller platform, via serial communication. The Arduino I/O pins will be triggered based on the information from Pure Data of which connected transistors will be activated, acting as a switch to draw in larger power supply to power the solenoids. The solenoids will then push the respective piano keys and produce music. The performance of CantaPlayer is evaluated by examining the synchronousness of the note playing sequence for a source MIDI and the corresponding reproduced MIDI. Three types of MIDI playing sequence (scale, polyphonic and rapid note switching) were tested and the results were satisfactory.

Abstract: Conventional electromagnetic valvetrain (EMV) usually uses double E-coils to control valve timings for engines. This kind of EMV needs large energy to reset valve at engine start state and requires energy to hold valve at opening or closing position. Therefore, it consumes large amount of energy. In this study, an EMV system that uses hybrid permanent magnet and electromagnetic coil together is proposed. The use of EMV in SI engines allows valve timings to be variably controlled without camshaft. Dynamic models for the new EMV have been built to simulate and analyze valve dynamics in this study. Effects of gas flow resistance on valve surface and the damping coefficient are also discussed. Besides, actuation strategy for valve releasing is investigated. The results show that the new EMV satisfies requirements about lifting time, actuation energy, valve velocity and acceleration in SI engines.

Abstract: Wireless sensor networks have inherent characteristics that differ from other wireless networks. Therefore, topology configuration and routing methods in WSNs must address these characteristics. In this paper, we propose an energy efficient clustering model. This model was inspired by the behaviors and capabilities of the six-spotted fishing spider, Dolomedes triton. The suggested model performs cluster-heads selection and clustering in self-organized ways. In order to determine the cluster-heads and the cluster-members, each sensor node uses the local information and simple rules that have been inspired by the Dolomedes triton. We compared our model with a well-known cluster-based routing protocol that uses random fairness for the selection of sensor node cluster-heads. In our computational experiments, we have showed that the energy efficiency and lifetimes of our bio-inspired model exceeds those of the comparison protocol by only using simple bio-inspired mechanism. We also demonstrate our model’s good performance in terms of scalability, which is one of the important indicators of performance for self-organized wireless sensor networks.

Abstract: For many interactive vision based systems, users are captured by the system and modeled as a simplified skeleton. The skeleton model usually encounter problems of occlusion because of obstacles or other users appearing in the environment. In this paper, we proposed a method based on an inverted pendulum model (IPM), which was applied to recover the occluded leg of skeleton model. The skeleton model was provided by Vicon motion measurement system, which captured the participant's motions. One leg of the skeleton model was removed intentionally and the proposed method was used to estimate the pose of the occluded leg in real-time. The results showed that most of the positioning errors were within 10 cm on average and the processing rate exceeded 100 fps.

Abstract: In this paper, a grade diffusion algorithm is proposed to solve the sensor node’s transmission problem and the sensor node’s loading problem in wireless sensor networks by to arrange the sensor node’s routing. In addition to them, the sensor node also can save some backup nodes to reduce the energy consumption for the re-looking routing by our proposed algorithm in case the sensor node’s routing is broken. In the simulation, the grade diffusion algorithm can save 28.66% energy and increase 76.39% lift time than the tradition algorithms for sensor node. Moreover, our proposed algorithm has the less data package transmission loss and the hop count than the tradition algorithms in our simulate setting. Hence, in addition to balance the sensor node’s loading and reduce the energy consumption, our algorithm can send the data package to destination node quickly and correctly.

Abstract: In this paper, we present a grating-coupled surface plasmon resonance (SPR) biosensor with a c-type fluidic channel on a grating disc. For obtaining the kinetic information of molecular interaction, we combined a c-type fluidic channel on disc to drive testing solution forward by gravity via turning the grating disc. The disc biosensor can react with probe molecules on the different sensing surfaces in the following time. The repeatability testing shows the resolution of angle of the measuring system was enhanced by threefold comparing to that without the automation improvement. In order to identify the accuracy of angle changes of SPR due to the chemical reaction on surface, experiment for monitoring a growth self-assembled monolayer (SAM) immobilized on gold surface was performed. The measured response curves show that the saturation time of the SAM formation, which thickness is smaller than 2 nm, is roughly 5 hours when 1 mM MHDA growing on gold at room temperature. The demonstration reveals that the disc biosensor with c-type fluidic channels can be a promising tool for a kinetic analysis of bimolecular interaction without any external fluid pumping systems.

Abstract: Purpose of this paper raise a vehicle lane departure warning system based on the machine vision. It does not need to use the parameters of the camera which do the road marking recognition system installed in the interior of the camera by algorithms. Regarding the time line of the intelligent transport system, it is to solve the various problems possibly arising from driving on the road. This system is mainly for the warning of the unexpected departure of vehicle. The method is to use the digital camera to capture continuous images and identify the vehicle moving direction by the detection of the left and right markings, as well as forecast the driving direction of the vehicle for the reference of vehicle departure warning. In this paper, the used algorithms include brightness adjustment, binarization, dilation, erosion, and edge detection image processing techniques.