Advanced Materials Research Vols. 328-330

Abstract: With the first kind of Lagrange’s equations, this paper presents the dynamical equations of multibody system with friction constraints. The generalized forces of friction forces are described in the form of matrix. Considering numerical method is widespread to analyze the characteristics of multibody system dynamics, this paper compares the two friction laws for solving the multibody system problem with dry friction constraints. Using Baumgarte’s and augmentation method, the differential-algebraic equations are given in the form of differential equations matrix to raise calculating efficiency. The friction force for Coulomb’s friction law and the continuous friction law is denoted, which converts subsection smooth systems to continuous smooth systems. An example is given to evaluate the validity of continuous law of friction. The numerical simulation shows that continuous law of friction is an effective method to process multibody system friction problem. The work in this paper also provides a new direction to research the non-smooth multibody system dynamics equation.

Abstract: We can use video surveillance method to detection the weft in Glass fiber textile machine, avoids glass fiber weft bristling by contact weft detection sensor, Glass fiber dust damages to human health. Using Ant Colony algorithm of intelligent search, global optimization, robust, positive feedback, distributed computing, easy combination with other methods and other characteristics, resolve image segmentation, extraction monitor weft system in regional conditions, then use the default rule-based artificial intelligence reasoning in the region separately.

Abstract: Tire blowout is a very serious security incident, particularly on the highway. As the existing anti-blowout device and measures also failed to meet the requirements to ensure traffic safety, research and development of prevention and treatment system is particularly important. In light of this, the Tire Pressure Monitoring Inflatable Restraint System is put forward. Sensor can send signals to the controller, and then the controller directs the gas generator to generate a lot of gas instantly, and through a special airway tire is inflated, so that the instability of the vehicle is eased. The concept of "vacuum tube tire" is first proposed, it can adapt to the inflation process better. Tire blowout, drunk driving and speeding is called together "three big killers on road" in China, so we can see that there are many incidents like these. Meanwhile, tire blowout is not like the other two which can be prevented by human’s means, it is sometimes not within our control. According to statistics, 70% of national highway traffic accidents are due to tire blowout, and a speed of more than 160km/h makes mortality possibility up to nearly 100%. In the check of the tires, more than 40% of them have security risks. [1] Statistics show that: The main reason why traffic accidents of high-speed driving keep increasing is leaked or inflated tires. In China, there is statistical data show that 46% traffic accidents on the highway were due to tire problem, in which tire blowout accounts for more than 70% of the total accidents, and the most crucial reasons of this is because the owners’ improper tire maintenance method. Beyond the boring concept, we can see a bunch of rather alarming figures, accounting for 49.81% highway accidents deaths, 63.94% injuries, 43.38% direct property loss were caused by high-speed tire blowout. High-speed tire blowout is considered to be the super-killer of traffic safety. And all the tire blowout incidents warn people to pay attention to tire safety.

Abstract: In view of the disadvantages on working vibration or even cannot work of broaching machine derived by broaching-load’s uncertainty, a testing system of broaching-load is designed. The testing system uses an industrial computer, a high-precision data-acquisition-card, two pressure-sensors, a displacement-sensor and Borland C++ to test the broaching-load on the base of broaching machine’s electronic control system. The factual application in hydraulic broaching machine shows that the proposed system has a good performance on testing-accuracy. The proposed system gives an effective solution to broaching-load testing.

Abstract: In order to realize precise contact tasks with an unknown environment, robotic force controllers have to adapt themselves to the unknown environment. Some impedance controllers are designed for several representative environmental parameters, A BP neural network is proposed to determine the one-to-one mapping relations between the environmental parameters and the impedance parameters. However, it is difficult to accurately know the environmental parameters in the case of a changing environment, RLS is proposed to estimate environmental parameters, then determine the impedance coefficients to control the robot. Simulations prove that the controller designed is feasible and effective.

Abstract: In this paper, the method of combining the time-domain analysis of empirical mode decomposition (EMD) and fuzzy clustering is explored for the hoist gearbox fault diagnosis. Firstly, it adopts the EMD technique to decompose the signal of vibration. With it, any complicated dataset can be decomposed into a finite and often small number of intrinsic mode functions (IMFs). Then a number of IMFs containing main fault information were selected, from which time domain feature parameters-- variance and kurtosis coefficient were extracted. At last, fuzzy clustering is used to diagnose and identify the kind of fault. The numerical simulation and the analysis of the response signal data from the hoist gearbox show that the method is effective at discriminating the three condition of the gear, i.e. the normal, surface fatigue pitting and cracked tooth.

Abstract: Based on the working principle of the TC2400 Tower-belt, the power bond graph of the hoisting mechanism hydraulic system was established under the listing loads condition. The dynamic equations of the system were deduced according to the logical relations amongst the established power bond graph variables. Based on the dynamic equations of the system, the system’s simulation model was established using the block diagram of SIMULINK. By setting the simulation parameters of the hydraulic system, this simulation was carried out, and the performance curve of the hydraulic system was obtained. The simulation results checked the validity of the simulation method, proved the feasibility to build model and simulate the hydraulic system of the large construction machinery by combining power bond graph with SIMULINK, and provided a theoretical direction for improving and optimizing the system.

Abstract: This paper describes a new laser engraving system for automation. It is a different open system from traditional ones. The system excludes sealed machine housing so that it is convenient for automatic loading and unloading. This paper also discussed safety issues which came with the open housing structure. At the end of this article, you will find the design of automatic loading and unloading with pneumatic components and a PC-based controller.

Abstract: About thirty years ago, the concept of the complexity of the problem was proposed. The most important complex class is P and NP class. Fruitful results of this concept are the existence of the so-called complex class complete problem. If the other issues of this class once solved in polynomial time, then the problem must exist polynomial time algorithms. Therefore, the complete problem is most difficult to solve, but because of their presence, we can choose any of them improved algorithm for a problem, so this kind of problem to get a good solution. DNA computing is a novel method that solving a class of intractable computational problems, in which the computing speeds up exponentially with the problem size. Up to now, many accomplishments have been made to improve its performance and increase its reliability. Maximum Independent Set problem (MIS) is a well-known NP-complete problem. Maximum Clique and Minimum Vertex Covering problem is equivalent to Maximum Independent Set problem. In this paper, we explore solving Maximum Independent Set problem by transforming it into equivalent 0-1 programming problem, and utilizing the surface computing model of that. The proposed method demonstrates universal nature of NP-complete problem.

Abstract: A longitudinal vibration coupling with a flexural vibration in a curved fluid-filled periodic pipe is studied. The pipe is fabricated by a periodic composite material structure based on the Bragg scattering mechanism of Phononic Crystals. Using the transfer matrix method, the band structure of an infinite periodic straight pipe is calculated, and the elastic wave propagation characteristics of the periodic pipe are discussed. Furthermore, the vibrational frequency response functions of a finite curved pipe are performed and the coupled vibration is studied. Finally, the transmission properties of longitudinal vibration, flexural vibration and their coupling vibration in the curved periodic fluid-filled pipe are investigated.