Advanced Materials Research Vol. 902

Abstract: Acoustic Pyrometry enables non-intrusive, accurate, reliable gas temperature measurements which can be used for controlling operations on real-time basis, therefore, it particularly applies to hot zones and extremely harsh environments. In the application study on multiple acoustic paths intersection in temperature field measurement, two key techniques that time of flight (TOF) of acoustic waves measurement and temperature field reconstruction were involved. This paper introduces the development of Acoustic Pyrometry, and then focus on two key techniques. The cross-correlation algorithm to calculate the TOF and least-square method for temperature field reconstruction are presented. The advantages and limitations of these techniques are also discussed. Several emerging questions are proposed.

Abstract: With the increasing development of ocean engineering, towing extending-retracting equipment used widely is the basic platform realizing the engineer value of towfish. In this paper, the dynamic model of the equipment in rough sea condition is created based on Adams, and the operating parameters are determined by maximum dynamic load, as the input data of static model of the equipment. Then the static models of capture unit, swing arm and base frame are created to calculate the strength respectively. Lastly, from the results, the valuable suggestions are put forward to provide valuable references for optimization design and engineer application in future.

Abstract: Shipborne dropping system is used widely in national defense and ocean engineer. Dropping system is moving with ship in voyage, so it's difficult to analyze precisely the strength of dropping system resulting from the complex dynamics. To solve the problem, firstly based on ADAMS software, in the paper the dynamic model is created and analyzed, and maximum load of every part of dropping system is achieved one by one. Then, static analysis of every part is researched to checkout structural strength based on ANSYS software platform, and improving part structure with weak point. In the paper the method and research make sure that the dropping system is safety and available.

Abstract: This work presents an experimental characterization of three types of ground commonly found in urban centers regarding their absorption properties with respect to sound propagation: asphalt, grassland and soil. A brief theoretical background is presented, and the experimental procedure is discussed in detail. With basis on experimental results, it is concluded that grassland ground is mostly absorbent for all tested frequencies, whereas asphalt and soil are reflexive for low frequencies and absorbent for high ones.

Abstract: After the analysis of the requirements of starting and shifting process of vehicle equipped with Automatic mechanical Transmission (AMT) system, the AMT control quality evaluation test is designed. The test includes performance test and control strategy benchmarking test. Data from CAN bus and external sensors are collected by CANoe which makes the data synchronization. By processing the collected data, the transmission performance can be evaluated in objective and the feasibility of the test system is also verified.

Abstract: The variable tension control system of strip winding is a nonlinear, strong coupling and time-varying system. Traditional fuzzy controller with fixed control rules cannot obtain the desired control performance of the strip winding system. So the fuzzy control algorithm with adjustable factor α is proposed, and the introduction of adjustable factors can change the fuzzy control rules. The tension fuzzy controller with adjustable factor α is designed, and simulation model of the system is established using Matlab software. The result of simulation shows that tension fluctuation of the tension fuzzy control system with adjustable factor get small, comparing the tension fuzzy control system with adjustable factors with the ordinary tension fuzzy control system. The tension fuzzy control system with adjustable factors has fast system response and strong anti-interference ability.

Abstract: The wheeled mobile robot has been widely used in various fields nowadays. Combining with a contest of mobile robot used for sorting and conveying objects, this paper designed a non-tracking wheeled mobile robot, which can move according to a reasonable route planned beforehand. First, the overall schematic design of mobile robot was introduced. Then the mechanical design and the circuit system design were discussed in detail. Last, the strategy of sorting and conveying was studied, and the innovative rotary-wheel mechanism can greatly simplify the sorting and conveying strategy. Through experiment verified, the proposed wheeled mobile robot can quickly achieve sorting and conveying according to preplanned paths.

Abstract: A novel electromagnetic unmanned robot applied to automotive test (URAT) based on the conversion principle of electric-magnetic-force is proposed. Electromagnetic URAT adopts electromagnetic linear motor (EMLM) as its drive mechanism. The mechanical system structure and the control system structure of electromagnetic URAT are designed. The coordinated control method of multiple manipulators is given. Experiments are performed using a Ford FOCUS car. Experimental results shows that electromagnetic URAT can smoothly achieve starting, acceleration, shifting, steady speed and deceleration. The overshoot of speed tracking control during transition from the acceleration stage to steady stage is small. Moreover, the speed fluctuation at the steady stage is smooth, and the speed control accuracy can meet the requirements of national test standards. The robot can automatically drive different vehicle models instead of human driver without need of any automobile modification.

Abstract: This work proposes a feedback linearization control algorithm to be applied to a pneumatic positioning system. Such algorithm aims to compensate the undesirable effects due to the highly nonlinear dynamic behavior of such type of actuator. A mathematical model of the system is presented and the proposed controller is described. Besides, an analysis is provided of the convergence properties of the closed-loop tracking errors of the system when such controller is used. The main features of the proposed controller are illustrated by means of experimental results and respective discussions.

Abstract: This paper deals with the nonlinear control of pneumatic servo positioners. It is proposed the use of a neural network technique associated with a nonlinear cascade control strategy, as a means of bypassing strong difficulties common to the practical implementation of model based strategies in pneumatic systems control. Such difficulties are associated to the precise plant identification that, in the case of pneumatic servo positioners, is usually very complex and hard to find. The experimental results of position tracking control presented in the paper allow us to conclude that the neural network technique applied in this work can avoid the need of execution of time expensive experiments usually required to perform precise identification of the plant characteristics used in model based control strategies for pneumatic servo positioners.