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Power transformers and shunt reactors play an important role in electric power transmission and distribution. They are very expensive capital investments. For these reasons it is necessary to maintain safe, reliable and uninterrupted operation of transformers and shunt reactors. Interaction of operating conditions and degradation factors with key subsystems of transformers/shunt reactors can cause excessive degradation and has a significant impact on their overall lifespan. Factors such as increased loading, temperature and moisture can lead to failure, end their serviceability and can create serious problems. There is a tendency to predict failures, prevent their inception and discover them in time. Routine diagnostics, monitoring systems, and protective and safety devices all contribute to the reliable and safe operation of electrical equipments. Article deals with the gas generation within the paper-oil insulation system during the aging and failures. Production of different gases is typical for particular failures. Furthermore, there is presented post mortem analysis of a shunt reactor failure accompanied by a rapid accumulation of combustible gas. Moreover there is shown the gas generation monitored by several sensors during the failure. Shunt reactor was switched off by dispatch control engineer because of well-timed Buchholz relay tripping. [ABSTRACT FROM PUBLISHER]

Spring clip are widely used in modern rail fastening systems. Cyclically varying stress appear in the spring clip when the railway vehicle passes. This leads to fatigue cracks in the spring clip and their subsequent destruction. Thus, increasing the fatigue strength of spring clips is an urgent task in the development of railway transport. The paper considers a spring clip in the fastening of a rail with reinforced concrete sleepers (fastening ZhBR-65). The finite element modeling of the loading process of the ZhBR-65 spring clip has been carried out. The maximum stress intensity σi was 411 MPa. A new design of a spring clip has been developed, in which the arc sleeper sections (adjacent to the sleepers) are made with a barrel-shaped cross-section. The safety factor of the resulting structure is 1.22 times higher than that of the standard ZhBR-65 spring clip. [ABSTRACT FROM AUTHOR]

In automated manufacturing, cutting process monitoring is vital, because without an operator, significant machine downtime associated with cutting tool failures is possible. The vibroacoustic signal parameters during cutting have long been used as a source of information about the cutting process state. This paper presents the results of the investigation of the spectral composition changes of vibrations over time during the cutting process due to changes in the quality of fastening of cutting inserts and modules of a modular boring tool setup with a large number of elements. [ABSTRACT FROM AUTHOR]

During the past years, there is an increased derailment scenario due to track faults. To resolve this issue, an intelligent visualization-built rail inspection system, which is automatic and real time has been developed. The system strongly notices important rail components like draws, tie plates and nuts and bars which helps in rail fastener with more accurateness and effectiveness. In current years, the railway transportation system developed as one of the chief resources of transport. Hence, the safety in the railway line is of more important. However, due to the expected multiple breaks of elastic rail clips in a fixed rail, accidents may rise when a train is permitted through the track. To attain this goal, a group of image analytics have been developed first and then planned an original universal optimized outline to associate evidence from numerous television camera, sensors and remoteness gauging device to further progress the detection routine. Complete track analyses have been ensured and provide clearance to the train motion only when the track health is perfect. This paper aims at completely reducing the human interference. Quantitative analysis has been completed on a big image set of data taken with diverse track and light circumstances and on a real–time field test. The fist system used to handle and resolve both module and omission finding and exception handling problems. [ABSTRACT FROM AUTHOR]

Cold formed steel sections are extensively used in developed countries for a wide range of applications like roofs in the form of deck sheeting and also as structural elements like beam and column. In a developing country like India, where use of conventional hot rolled steel sections itself is in developing stages, the use of cold formed steel is very less. But if cold formed built-up sections are developed efficiently, cold formed sections can be used for wide range of applications where spans are minimum and fewer loads are acting. Structural behaviour of cold formed sections based on the different type of fasteners was studied in this paper. Behaviour of cold formed sections mainly based on welding and bolts are compared and studied. Strength aspects of cold formed sections due to different types of fasteners along with their mode of connection was studied. Studies shows significant changes in behaviour of similar members were obtained by varying the type of fasteners. [ABSTRACT FROM AUTHOR]

Structural materials, such as composite panels, can only be assembled, and in most cases through the use of fasteners, which are fitted into the drilled holes. However, drilling is costly and time consuming, thus affecting productivity. This research aims to develop an alternative method to drilling. In this paper, the precision of the holes was measured and the effects of the die clearance to the areas around the holes were evaluated. Measurement and evaluation were performed based on the profile of the holes constructed using Alicona IFM, a 3D surface measurement technique. Results showed that punching is a potential alternative to drilling but still requires improvements. [ABSTRACT FROM AUTHOR]

In this paper, the new wall climbing robot, ‘Mo-Mo’, is introduced. The MoMo can be sensor mounted device for the intelligent space and the devices can be rearranged by themselves according to the situation of space through using the mobile mechanism of MoMo. The MoMo uses the screw-nut mechanism to stick to the wall and the ceiling. This mechanism makes the MoMo to be stable condition while the MoMo is not moving. Furthermore, it leads to the position error of MoMo up to a certain range. The mechanism of MoMo and the evaluation of its performance are shown in this paper. [ABSTRACT FROM PUBLISHER]

In the pursuit of high precision in a modern CNC machining system, it is significant to eliminate thermal error. The paper first makes a brief outline of the characteristics and the training methods of neural networks. And it is successful to apply the neural network model to model the thermal error in the CNC machine linear feed system. The expected results is achieved that the maximum prediction error reduced to 2 um, laying a further foundation for thermal error compensation. The text describes the actual modeling process in detail. And a new method of data preprocessing is come up with according to the specific characteristics of training data. It is an innovative point of this paper to apply the method to model training better. [ABSTRACT FROM PUBLISHER]

Power-to-weight ratio of actuators is extremely important for robots, particularly mobile robots. The combination of electric motor and speed reducer, which is the most common driving mechanism for robots, can utilize the motor in the area where its power output is high when the reduction ratio is appropriately designed relative to the load. However, in the case of applications in which the load significantly changes, the motor has to be operated in the area where its power output significantly drops. This problem has restricted the capability of mobile robots, especially biologically inspired robots. Therefore in this paper I focus on a continuously variable transmission (CVT). Crank-type CVTs, which have been used for robotic joints, have the major disadvantage of a limited range of motion due to the dead point of the crank. Thus, this paper proposes the Radial Crank-type CVT (RC-CVT), which overcomes this limit of range of motion by increasing the number of links driving the crank of the CVT. This RC-CVT holds promise as an efficient robotic joint as it can utilize ball screws. This paper shows the equations of kinematics and statics of the RC-CVT and also describes the design and test of the prototype. The application to a quadruped robot is also introduced. [ABSTRACT FROM PUBLISHER]

While cable-driven systems offer the advantages of being lightweight with low moving inertia, the unilateral driving property of cables generally require them to have a greater number of actuators than their rigid-linked counterparts. This paper investigates the use of springs in an attempt to reduce the number of cables required. Given an n-DOF spring-loaded cable-driven open chain, several important questions arise: (i) How can force-closure analysis be carried out for a given spring and cable routing configuration? (ii) Are n+1 cables still necessary to fully constrain the entire open chain? (iii) What is the influence of spring placement on force-closure and cable tension required? This paper will address these concerns by proposing a systematic approach based on reciprocal screw theory. The analysis shows that an n-DOF spring-loaded cable-driven open chain still requires a minimum of n+1 cables to fully constrain it. From preliminary analysis, spring placement can have a positive effect on altering the cable tension required and increasing the feasible workspace. [ABSTRACT FROM PUBLISHER]

The paper demonstrates the process of development of a bending device for a springback study. The numerical analysis of a V-bending device work as well as its optimization and experimental verification are presented. The study was conducted for the samples made of S235 structural steel. The main difference between the proposed device and a well-known device for V-bending lies in sample fastening to the punch head and a larger die radius in relation to the sample thickness. The presented bending device is characterized by a larger springback angle, less dispersion of the results and lack of the sample reverse loading. [ABSTRACT FROM AUTHOR]

An investigation has been made to predict the accurate fastener stiffness for the Aircraft metallic joints that can be used in Finite element models to simulate realistic behaviour. There exist several semi empirical equations like Tate & Rosenfeld (1946), Huth-Schwarmann (1986), Swift (1971) & Grumman (1983) etc. that can be used to calculate the shear and stiffness of fasteners. However the stiffness calculated varies for each of these methods and eventually leading to varying load distribution. In this paper a parametric study has been conducted to identify the most accurate method to identify the fastener stiffness. The relevant shear stiffness calculated adds certain flexibility to fasteners and peak loads tend to distribute across all the fasteners matching with the real scenario. [ABSTRACT FROM AUTHOR]

The objective of this paper is to design a rotating speed function of a ball-screw system with the aim of lowering the peak acceleration value of the slider. For the purpose of analyzing the kinematic characteristics of the system, the normalized motion equations of the ball-screw system were derived. From the analysis, a set of design rules was devised and a rotating speed function of was designed. It was revealed from computer analysis that as the rotating speed function was applied to the screw input, the peak acceleration value of the constant pitch screw, operated at a constant speed, was decreased. For comparison purpose, a computer-controlled experimental device for characterizing the kinematics of a ball-screw system was also designed and manufactured. The results from the tests and the analytical model were comparable. [ABSTRACT FROM PUBLISHER]

One of challenges in building insect-sized flapping MAVs (micro air vehicles) is to realize complex wing motions under severe design limitations in mass and size. In this paper, two examples of insect-sized flapping mechanism which reduces the mechanical complexity of the wings by utilizing flexible structures: One is a 1-DOF butterfly model and the other is a 2-DOF Diptera model. The butterfly model flew forward stably without any active control device. The flight speed depended on the wing flexibility determined by the wing venation pattern. It was found that the venation mimicking a real butterfly prevents excess feathering deformation of the wing, resulting in slow flight. In the 2-DOF Diptera model, wing pronation and supination were realized passively with a flexure film hinge at the wing root. Tethered flapping experiments showed that lift was maximized by optimizing the hinge stiffness. It was also demonstrated that corrugated cross sections of Dipteran wings are useful to increase spanwise stiffness of flexible artificial wings. [ABSTRACT FROM PUBLISHER]

In this paper, we introduce a new framework for registering pre-operative 3D volumetric data to intra-operative 2D images. We are particularly interested in examining the problem of aligning CT volumes to corresponding X-ray images. Our objective is to apply the 2D-3D registration in the field of orthopedics, specifically on ankle surgery. The long-term goal of this work is to apply this technique to ankle fusion surgery to determine the proper size and orientation of the screws which are used for fusing the bones together. In addition, we try to localize the best bone region to fix these screws. Our framework adopts the shear-warp factorization method to generate synthetic 2D images from the given 3D volume. Also, the alignment score is determined according to Exponential Correlation (EC) as a new similarity measure. We used a variety of methods to evaluate registration quality of our system. It has been tested on 15 clinical CT datasets. Evaluation results indicate the degree of accuracy of our registration framework. [ABSTRACT FROM PUBLISHER]

In this paper, the concept of Reconfigurable Intelligent Space, ‘R+iSpace’, is introduced. The R+iSpace is a reconfigurable system according to situation of the space through rearranging devices in the space. For rearranging devices, the mobile module MoMo is proposed. The design of MoMo is described, and the performance evaluation of MoMo is performed in this paper. [ABSTRACT FROM PUBLISHER]

With the rapid development of cognitive radios, spectrum efficiency in cognitive radio networks (CRN) has increased by secondary users (SU) accessing the licensed spectrum dynamically and opportunistically without creating harmful interference to primary users. However, the performance and security of CRN is considerably constrained by its limited power, memory and computational capacity. Fortunately, the advent of cloud computing has the potential to mitigate these constraints due its vast storage and computational capacity. In this paper, we propose secure radio resource management algorithm for CRN where cloud computing unit stores the spectrum occupancy information of heterogeneous wireless networks in CRN and facilitates the access of spectrum opportunities for secondary users. The proposed algorithm leverages the geolocation of secondary user and idle licensed bands to facilitate the secure allocation of radio resources to SU. Furthermore, the secondary users who provide high benefit are admitted while satisfying the quality of service (QoS) requirement of secondary users in terms of data rate and service time. We also present the design to implement the proposed algorithm on Cloud computing platform, and propose a scalable mapping method under the Storm, real time processing model to dynamically partition the geographical area according to the SU density. Simulation results are presented to demonstrate the performance of the proposed secure radio resource management algorithm. [ABSTRACT FROM PUBLISHER]

Wood chips properties variation is known as a source to provoke variability in thermo-mechamical pulping processes. This mainly includes density, moisture content and brightness of the chips as the raw materials that result in consuming more refining energy and bleaching agent as well as degrading product quality. To date, no concrete control strategy has been proposed to reject the effect of the raw materials variation especially due to the lack of on-line real-time measurement of the latter. Recent technological advancement fills up this gap which permits developing complementary control strategies in the perspective of more efficient TMP process. A new concept is proposed in this article to take the advantage of current technological advancements to improve TMP process efficiency. [ABSTRACT FROM PUBLISHER]

The focus of this paper is on the design and evaluation of a robust drive mechanism intended to robotically steer a thermal ablation electrode or similar percutaneous instrument. We present the design of an improved screw-spline drive mechanism based on a profiled threaded shaft and nut that reduces the part count and simplifies manufacturing and assembly. To determine the optimal parameters for the profile shape, an analytical expression was derived that relates the tolerance between the nut and shaft to the angular backlash, which was validated using SolidWorks. We outline the forward kinematics of a steering mechanism that is based on the concept of substantially straightening a pre-curved Nitinol stylet by retracting it into a concentric outer cannula, and re-deploying it at a different position. This model was compared to data collected during targeting experiments performed in ex-vivo tissue samples where the distal tip of the stylet was repositioned in ex-vivo bovine tissue and the location of its distal tip was recorded with CT imaging. Results demonstrated that the drive mechanism operated robustly and targeting errors of less than 2mm were achieved. [ABSTRACT FROM PUBLISHER]

It is widely acknowledged that the actuator's intrinsic backdrivability is important in realizing a force sensitive behavior. It is desirable to realize such actuator with electric motor that is advantageous from power-to-weight ratio and controllability point of view. Electro-Hydrostatic Actuator is a type of hydraulic actuators that can realize high backdrivability by reducing transmission friction and by providing dynamics decoupling with an implicit serial damper. To farther enhance the backdrivability of a EHA, a pump with minimum static and Coulomb friction is necessary. In this paper, we introduce an EHA with viscous screw pump that minimizes static and Coulomb friction by eliminating the mechanical contact between pump components. Viscous screw pumps also have the advantage that there is no pulsation in pressure due to the continuity of the force transmission from the rotor to the fluid. The property of the actuator, including pulsation performance and impedance control performance were evaluated on a prototype of EHA with a viscous screw pump. [ABSTRACT FROM PUBLISHER]

It is difficult to obtain analytical solution to forward kinematics for parallel mechanism, and the speed of the solution based on conventional numerical solution method is lower, and hard to achieve real-time performance in motion control. In this paper, in order to avoid the two problems, a continuous on-line estimation algorithm was proposed to approach the forward kinematics analytical solution exponentially. Taking the Stewart platform as example, its kinematics model was built, and then according a complex motion trajectory of moving platform given, the driving displacement of actuated joints was solved by inverse kinematics method, and then based on the driving displacement trajectory of actuated joints, using the continuous on-line estimation algorithm, the forward kinematics solution was obtained, the simulation results showed that the continuous on-line estimation algorithm can not only completely ensure real-time performance, but also attain very high accuracy, and so the continuous on-line estimation algorithm for forward kinematics can be applied in motion control of parallel mechanisms. [ABSTRACT FROM PUBLISHER]

The main purpose of this publication is to encourage the use of unmanned aerial vehicles (UAVs) by an engineering education approach for the protection of USA's borders and territories, in addition to providing citizens with extra safety measures and surveillance. Using a quadcopter based platform and training to undergraduate students, this paper explores the different features that a four-rotor UAV can add to the nation's safety. At this exact moment, our coasts are being remotely monitored by satellites as well as constantly patrolled by security officers and soldiers. However, there is a limit to the security that can be reached by these. In the case of satellites, though they've been the base of many security advancements, they cannot penetrate in certain terrains, something that can be solved by the use of UAVs. And, though the brave men and women in charge of guiding our coasts and safety are giving their best, they're only human and can use the help of these machines, especially in dangerous situations. But, they're many more cases in which these devices might prove useful. Take for example an emergency such as an earthquake or tsunami. These machines can help warn people of the situation and lead them to safety, as well as help localize victims. The latter can be done by incorporating heat-sensors along with the microphone and camera used for reconnaissance. The use of UAVs might just be what is needed to guarantee the safety of American citizens. [ABSTRACT FROM PUBLISHER]

The utilization of embossing process is in order to improve the mechanical characteristic of sheet metal. With using this technique subject to sheet metal, cross-section shape changed to be wave, hence, the section modulus of the embossed sheet metal is increased. In this present paper, we did the deep drawing test using duplex embossed sheet metal and measured the variation of flange position in case of the first half stroke. The flange deformation behavior was investigated. Furthermore, from the variation of strain ratio, material flow and fundamental planar deformation was clarified. [ABSTRACT FROM AUTHOR]

Honeycomb composite sandwich structures are now extensively employed in a variety of high performance engineering applications across several key industries, including aerospace. The advantage of such configurations is the ability to reduce weight, with increased strength and stiffness and very effectively carrying distributed loads along the normal direction of the core shell. One disadvantage of honeycomb core is the inherent weakness along the transverse direction making them unsuitable for point loads. As result of this, structural reinforcement of the core is required when mechanical fasteners are being used. This reinforcement can be accomplished with the use of a potting compound. Potting compounds are lightweight composite materials formulated from a polymer matrix, typically epoxy or phenolic, and various fillers, including hollow microspheres. However, among the many challenges of developing high performance potting compounds, is the ability to balance the high mechanical and compression strength with low density required to reduce the overall weight of the fabricated structure. This paper discusses the development of very low density potting materials (< 0.75g/cc) with excellent mechanical strength, including compression > 48 MPa (7000psi) at 180°C (350°F). Furthermore, developments in Flame Retardants, Smoke Density & Toxicity (FST) will be presented as opportunities for improved health & safety properties of potting materials for interior applications. Additionally, a detailed investigation of the rheology of the formulations will be presented, demonstrating superior handling and processing of the materials particularly focused towards automated dispensing to meet the increasing production demands and structural challenges of next generation aircraft design. [ABSTRACT FROM AUTHOR]

Wood trusses with traditional bolted or nailed connections are generally modeled as pinned joints, and the forces on the wooden members are directly transmitted to the connections by shear plane contact. Other methodologies recommend that the analysis should be done more rigorously, taking into account the wood behavior and the evaluation of stress distribution within the connection area. There is a wide range of related data to pin-type connections, but the mechanical analysis of punched metal plate fasteners (nail plates) is still under developed. Nail plate connections are capable of transfer moments, therefore, appropriated modeling should be applied. The present paper compares two methodologies for the stress distribution in the rupture lines of nail plates, using an analytical approach and a numerical method with the commercial software Midas/Gen. The results show a quantitative parity for the proposed analytical model in the case of a single joint line, but the stresses diverge in both methods for zones that presents more than one joint line. [ABSTRACT FROM AUTHOR]

Many industrial tasks-such as sanding, installing fasteners, and wire harnessing-are difficult to automate due to task complexity and variability. We instead investigate deploying robots in an assistive role for these tasks, where the robot assumes the physical task burden and the skilled worker provides both the high-level task planning and low-level feedback necessary to effectively complete the task. In this article, we describe the development of a system for flexible human-robot teaming that combines state-of-the-art methods in end-user programming and shared autonomy and its implementation in sanding applications. We demonstrate the use of the system in two types of sanding tasks, situated in aircraft manufacturing, that highlight two potential workflows within the human-robot teaming setup. We conclude by discussing challenges and opportunities in human-robot teaming identified during the development, application, and demonstration of our system. [ABSTRACT FROM AUTHOR]

The objective of this paper is to present a comprehensive approach to image processing for Giant Magnetoresistive (GMR) array sensors with sheet current sources for the inspection of fatigue cracks in complex metallic structures. The approach incorporates optimal phase angle adjustment, array sensitivity compensation, fastener site identification, an adaptive edge evaluation and removal algorithm and a classification metric. Processing examples are presented that highlight the benefits of these algorithms for improving crack detection for challenging edge and fastener spacing conditions. [ABSTRACT FROM AUTHOR]

The detection of embedded cracks under fastener heads (CUF) in multilayer structures is a major challenge facing the aviation industry. Eddy current (EC) based techniques, such as Magneto-Optic Imager, Sliding probe and Self-nulling EC probes, and low frequency EC methods have been investigated. The prior work of authors presented an EC system using a uniform field excitation combined with giant magnetoresistive (GMR) sensors for imaging the normal component of magnetic flux density, has improved the effectiveness in detecting 2nd and 3rd layer CUFs with aluminum fasteners. However, detection of CUFs with ferromagnetic fasteners remains a major challenge. This paper presents the experimental study of automatic crack detection under steel fastener sites using low frequency EC with 3D GMR sensors that measure all 3 components of the induced magnetic flux density. A finite element model based study is used to optimize the system design and the experimental validation is presented. [ABSTRACT FROM AUTHOR]

This paper presents a 3-UPU spatial parallel mechanism for the rehabilitation of hip joint which can be broadly used in the rehabilitation robot, although the hip medical rehabilitation robot is rarely usage today. This parallel mechanism has three rotational DOFs, and the rotation axes intersect at one point, so it's very suitable to implement the rehabilitation of the hip joint where has three rotational DOFs. This paper analysis the characteristics and movement mechanism based on the screw theory, provides a new method to research the parallel mechanism. [ABSTRACT FROM PUBLISHER]

It has been widely acknowledged that consideration of the random field is quite significant to accurately predict variability in system performances. However, current approaches for characterizing the random field can only be applied to the situation with sufficient random field data sets and are not suitable to most engineering problems where the data sets are insufficient. The contribution of this paper is to mo del the random field based on the insufficient data sets such that sufficient data sets can be simulated or generated according to the random field modeling. Therefore, available random field characterization approaches and probability analysis methods can be used for probability analysis and design of many engineering problems with the lack of random field data sets. The proposed random field modeling is composed of two technical components including: 1) a Bayesian updating approach using the Markov Chain Monte Carlo (MCMC) method for modeling the random field based on available random field data sets; and 2) a Bayesian Copula dependence modeling approach for modeling statistical dependence of random field realizations at different measurement locations. A refrigerator assembly example is used to demonstrate the effectiveness of the proposed approach. [ABSTRACT FROM PUBLISHER]

The work presented in this paper focuses on the design of a novel flexure-based mechanism capable of delivering planar motion with three degrees of freedom (3-DOF). Pseudo rigid body modeling (PRBM) and kinematic analysis of the mechanism are used to predict the motion of the mechanism in the X-, Y- and θ-directions. Lever based amplification is used to enhance the displacement of the mechanism. The presented design is small and compact in size (about 142mm by 110mm). The presented 3-DOF flexure-based miniature micro/nano mechanism delivers smooth motion in X, Y and θ, with maximum displacements of 142.09 μm in X-direction, 120.36 μm in Y-direction and 6.026 mrad in θ-rotation. [ABSTRACT FROM PUBLISHER]

Several studies have proved the efficacy of computer assistance in spinal surgery, especially in the technique of pedicle screw insertion for vertebral fusion and correction of deformities. Computer assisted surgical navigation systems have proven success in the surgical treatment of spinal fractures and disorders. We have developed a novel method for real time computer assisted spinal surgery, based on online video captured by using CCD camera. The paper presents a real time computer assisted spinal surgery for pedicle screw insertion. A video is considered to be a sequence of frames. Image processing techniques applies to video processing as well, however speed of processing is crucial for real time video processing. A system consisting of workstation computer, image sensors or cameras, digitizer and image processing hardware have been used for real time video processing. [ABSTRACT FROM PUBLISHER]

Injection molding is a nonlinear, multivariable process which involves several critical parameter settings for quality product. Determining optimal parameter settings is the challenging task due to the influence of environonmental conditions on the resin flow within the injection molding machine. This paper deals with various optimization techniques (differential evolution, DE, genetic algorithm, GA and Particle Swarm Optimization, PSO) which could be adopted to adjust the various process parameters of injection molding in accordance with level of error identified through quality checking. [ABSTRACT FROM PUBLISHER]

Mechanics is a subject based on experiments which usually are inconvenient and expensive in reality. Computer simulation is a reasonable substitute for real mechanics experiments, but traditional mechanics simulation approaches also have many disadvantages, such as low interactivity, low flexibility, low reusability, high development difficulty and etc. Considering that the traditional technique has many disadvantages, this paper proposes a new method-mechanics simulation based on game engine. In game engine, the physics engine provides a bottom technical support to make the mechanics apparatus run under the control of the physics laws. That increases the development efficiency greatly, and improves the interactivity, the flexibility and the reusability. This paper mainly discusses the advantages of mechanics simulation based on game engine, introduces the physics engine technology in detail and emphasizes on showing how to use game engine to simulate mechanical devices. [ABSTRACT FROM PUBLISHER]

Simulation of pedestrian evacuation in a room with fixed obstacles is presented based on cellular automata (CA) in this paper. Pedestrian moving rules are established, according to two-dimensional cellular automaton Moore neighborhood. The dynamic parameters: Direction-parameter, Empty-parameter and Cognition-parameter are formulated to simplify tactically the decision-making process of pedestrians, which can reflect the pedestrian judgment on the surrounding conditions and decide the pedestrian's choice of action. We propose the improved Dijkstra metric to compute the values of static floor field for evacuation system with obstacles based on the Euclidean distance. In order to show the advanced nature of our model, the simulation results of the improved and previous model are compared and analyzed. The simulation results correspond with the actual, it is instructional significant for pedestrian evacuation [ABSTRACT FROM PUBLISHER]

In recent decades, reticulated structure is widely used in large span spatial structures in China. It shows a trend of increasing span and more complicated. Based on the development of reticulated structures manufacturing industry both domestic and abroad, and the successful application experience of advanced manufacturing technology in other industries, a bolt-ball Joints CAD/CAM system for CNC machine is proposed in reticulated structure design software. It aims to build an integrated platform for engineering design and automatic machining. The external and internal manufacturing process of the reticulated structure is firstly introduced in the paper. Then a comprehensive study on the machining accuracy of bolt ball and the error of bar cutting are given. Finally, an integration solution of Bolt-ball net frame Structure CAD/CAM system on Solid Works platform is discussed. The work has theoretical significance and practical value. [ABSTRACT FROM PUBLISHER]

This paper presents an extremum seeking control (ESC) scheme for energy efficient operation of chilled-water system, and Modelica based dynamic simulation models for demonstrating the effectiveness of the proposed control strategy. The simulated plant consists of a water-cooled screw chiller and a mechanical-draft counter-flow wet cooling tower. The ESC scheme takes the total power consumption of chiller compressor and tower fan as feedback, and uses the fan speed setting as control input. The inner-loop controllers for the chiller operation include two PI control loops for regulating the evaporator superheat and the chilled water temperature. Simulation was conducted for different scenarios. The simulation results demonstrated the effectiveness of the proposed ESC strategy, and the potential for energy saving is also evaluated. Also investigated is the ESC windup issue caused by the limitation of the fan's maximum operation speed. A back-calculation anti-windup ESC scheme is applied and its effectiveness is validated by simulation results. [ABSTRACT FROM PUBLISHER]

Voronoi coverage control is the problem of locating vehicles at the centroid of their Voronoi cell. This problem is often used to model the task of deploying sensors to cover a planar area. Until recently, extensions to cover non-convex regions assumed visibility was never blocked. Nevertheless, visibility is an important consideration when deploying some types of sensors. This paper focuses on the problem of covering a region when non-convexities or holes in the region block visibility. A model of the problem is proposed, along with a method for solving it based on nonsmooth optimization. A convergence analysis is provided and the approach is evaluated through numerical simulations. [ABSTRACT FROM PUBLISHER]

The paper describes how to create and deploy a low cost platform for remote control of experiments via web page and a PIC microcontroller from Microchip. Thus we have a tool easily applied, by plug-and-play method, to optimize the learning and possibly spanning several types of students and institutions. [ABSTRACT FROM PUBLISHER]

Repetitive perfect tracking control (RPTC) is one of repetitive control techniques to achieve high precision positioning. In this paper, RPTC with n-times learning filter is proposed. n-time learning filter has a sharp roll-off property than conventional learning filter. By using n-times learning filter, proposed RPTC can converge tracking error n-times faster than RPTC with conventional learning filter. Simulations show the fast convergence of proposed RPTC. Finally, experiments in ball screw driven stage also show the effectiveness of proposed system. [ABSTRACT FROM PUBLISHER]

This paper reviews the requirement and consideration for standardizing Next Generation Wireless Form Factor (NGWFF) which is new thin and slim wireless form factor. It will replace the existing PCI Express minicard form factor. These requirement and consideration were submitted to the PCI SIG NGFF Working Group and included into the draft specifications of NGFF. [ABSTRACT FROM PUBLISHER]

This paper analyzes the problems existing in design and manufacture of the reciprocating screw in the spooling gear and proposes the solutions accordingly. By adopting software such as Solidworks and Unigraphics for three-dimensional design, a solid model meeting the design requirement can be obtained, providing good reference value for design and manufacture of the screw. [ABSTRACT FROM PUBLISHER]

For evaluation problems of kinematic accuracy reliability for folding and deploying mechanism under the condition of small sample,  the continuous contact effective coupling model considering gaps of kinematic pair is built by using "effective length model" theory; Based on the proposed kinematics model of folding and deploying mechanism, simulation calculation method of mechanism kinematic accuracy reliability is proposed by the Monte-Carlo method, kinematic accuracy reliability for folding and deploying mechanism of certain type missile wing is calculated, the attained reliability is 4.87% lower than that under condition of not considering gaps of kinematic pair. The calculation result shows that the reliability obtained by the method proposed in this paper is more closely to the engineering practice [ABSTRACT FROM PUBLISHER]

This paper considers the requirements for stable control of simple devices that consist of a permanent magnet rigidly attached to a screw operating in soft tissue. Placing these devices in a rotating magnetic field causes the device's permanent magnet to rotate synchronously with the applied field, making the attached screw generate forward propulsion. Although there has been significant research in the area of magnetic screws, this paper describes magnetic phenomena that have not been addressed in prior work, yet will be critical in the design of future steering and control strategies for medical applications. Using a time-averaged model of magnetic torque, we analyze the magnetic torque present when intentionally steering the screw or due to naturally occurring disturbances in the screw's heading. We predict and experimentally demonstrate the existence of magnetic torques that simultaneously act to stabilize and destabilize magnetic screws operating in tissue. We find that there exists an applied field rotation speed, above which screws may become unstable, and we find that the interaction between the stabilizing and destabilizing magnetic torques may cause potentially undesired but predictable behavior while steering. [ABSTRACT FROM PUBLISHER]

This paper is describing a methodology of improvement project that is carried out in a company that supplies electronic communication plastic parts. By using the lean tools, the focus of the paper is to improve the manual assembly line by adopting lean tool for the process improvement. The process improvement are divided into several phases, from defining the goal until the test run of the solution, with different lean concept being used at different phase. The improvement had been done phase by phase in order to ensure the impact of the improvement. Through the test run, the proposed solution based on concept of Lean production increase profitability based on idling time reduction (81.64%) and operator saving(40%) in operation. [ABSTRACT FROM PUBLISHER]

This paper reported on the experimental performance of mortise and tenon joint for beam-to-column structural member made of Kempas species. The joints were dowelled with glass fibre reinforced polymer (GFRP) and compared to the joints strengthened with steel dowel and wood dowel. The failure modes performance analyses were observed based on European Yield Model (EYM) theory according to National Design Specification (NDS) 2008. Results show that the experimental performance of the mortise and tenon joints dowelled with GFRP under tensile load may provide comparable strength to the joints dowelled with steel. The sequence of having the higher capacity to hold the mortise and tenon joints is by strengthening it using GFRP, followed by steel and wood dowel. The failure behavior of both joints dowelled with steel or GFRP were almost similar. Nevertheless, different behavior was shown in wood dowelled joints, the flexibility of wood dowels extended the displacement longer made the yield load and load at rapture extended compared to the other types of joints. [ABSTRACT FROM PUBLISHER]