Advanced Materials Research Vols. 328-330

Abstract: The principle and structure of self-adaptive scaling factor fuzzy controller is introduced, which is composed of host fuzzy controller and auxiliary fuzzy controller. Auxiliary fuzzy controller produces a quantity to update real-time scaling factor according to control process error, variation of error and the relationship of error, to obtain better system control performance. According to characteristics of NC feeding servo system, the fuzzy controller is applied to control the NC feeding servo system. In order to check the dynamic performance and stable error of system, the controller is simulated with fuzzy toolbox and Simulink environment in Matlab. The results show that the self-adaptive scaling factor fuzzy controller is good for NC feeding servo system.

Abstract: Though computer technology has brought about virtual manufacturing to expedite design and analysis through simulation and visualization, machines remain essential, as ultimately products need to be made. There is a need for equipment providing more than three degrees of freedom (DOF) arranged in parallel and based on simpler arrangements than 6-DOF arrangements in application. This paper presents a new 4-DOF hybrid parallel platform manipulator with fixed-leg lengths and base mounted prismatic actuators. The movable platform of the manipulator can translate along two directions and rotate around two axes respectively (2T-2R). The kinematics model is formulated, which describes the inverse and forward kinematics transformation. It is very easy to develop a 5-axis NC machine-tool which is of large-workspace based on the 2T-2R, 4-DOF parallel mechanism presented in this paper.

Abstract: The paper propose the digital frequency multiplying method based on frequency de-noising on FPGA, aiming at the frequency aliasing of the high frequency interference in the power system frequency tracking circuit. The basic principle and hardware realization are discussed.The performance of the system is tested using two different system clock, the experiments show that: This method can eliminate the error caused by frequency aliasing, and improve the interference immunity of the system. In addition, experiments also proved that using higher system clock can improve accuracy absolutely.

Abstract: Online sensors which are used to testing moisture play an important role in greenhouse system. Testing moisture which sensors is a key role to the accuracy is very important to agricultural development. The character of the sensors was directly associated with the development of greenhouse automatic system. There is no doubt that the structure of the sensors is critical to the testing results. A study of different sizes of sensors and the structure of capacitance sensors on precision was studied in the paper. We design the structure of the sensors and then conduct an experiment. According to the experiment, we decide the best size of the sensors.

Abstract: In this paper, the continuity equation, momentum equation and the k-ε turbulence equation were introduced to simulate the flow field of the multiple vortex bodies in different spacing cases. Found that each vortex body had good effect in producing vortex, and the greater flow field spacing, the smaller the highest velocity; the turbulence intensity is increasing gradually from the former vortex body to the next one, and there may be a best spacing between the vortex bodies which makes the best turbulent intensity. All of these theories provide a train of thought for the turbulent coalescence mechanism.

Abstract: In order to achieve the intelligent control of milling process, an experimental platform is constructed in XK5140 CNC machine tool. The control system is based on the Simulink model of MATLAB and the controller is established by programming S-function. The experiments are performed on steel workpiece with variable depth of cut by controlling milling force. The experimental results show that the intelligent control of the milling process is feasible using this experimental platform. The proposed controller can adaptively adjust the feed rate till achieving a constant cutting force approaching the set point in varied cutting conditions. CNC milling machine can make full use of its manufacturing capacity when processing the parts, thus improving the cutting efficiency and protecting the tool.

Abstract: A novel approach is proposed for measuring fabric texture orientations and recognizing weave patterns. Wavelet transform is suited for fabric image decomposition and Radon Transform is fit for line detection in fabric texture. Since different weave patterns have their own regular orientations in original image and sub-band images decomposed by Wavelet transform, these orientations features are extracted and used as SOM and LVQ inputs to achieve automatic recognition of fabric weave. The experimental results show that the neural network of LVQ is more effective than SOM. The contribution of this study is that it not only can identify fundamental fabric weaves but also can classify double layer and some derivative twill weaves such as angular twill and pointed twill.

Abstract: A new type of temperature measurement apparatus is designed by utilizing the characteristic that the velocity of the ultrasonic wave varies with the temperature through the medium, with both merits low cost and high precision. This paper introduces the principle of ultrasonic thermometer and puts forward the realization of hardware and software of thermometer, and details the special software subdivision algorithm which is used to measure the ultrasonic transmission time accurately. The experimental results indicate that the thermometer achieves the measure of the ultrasonic wave transmitting time with nanosecond level. The key problems are solved in the practical application of the ultrasonic temperature measuring technology, and the resolution of the temperature measurement is better than 0.001 centigrade.

Abstract: In a Certain Mining Engineering, it’s Needed to Collect the Ore Bearing Sandy Soil with Certain Thickness from the Ground Surface. in Order to Realize Accurate Collection, it’s Needed to Control the Collecting Thickness Strictly. the Application of Contacting Type Landform Detecting Method in the Engineering Machinery Was Discussed, and a Kind of Mechanical Contacting Landform Detector Was Developed for the Alluvium Landform of Mining Area in Gobi with Loose, Rough and Uneven Ground Surface. the Landform of Soft Sandy Soil Can Be Detected by Controlling the Contact Pressure between the Depth Wheel of the Detector and the Ground Surface. with the Use of PID Control Technology with Wave Filtering, the Real-Time Detection Accuracy of the Detector for Mixed Sandy Soil Ground Surface Reaches ± 3mm. this Detector Is Specially Used for Milling, Planing and Collecting Device, Achieving Uniform Thickness Collection of Ore Bearing Sandy Soil in Rolling Topography Condition.

Abstract: As stroke is one of the most morbidity disease, some rehabilitation devices has been developed to solve the problem, but there isn’t maturation in hand. This paper presents a new hand exoskeleton rehabilitation device to improve the result of rehabilitation and help doctors to perfect theory about hand rehabilitation. We set 8 DOF in this three fingers device, with 2 active DOF and 1 coupled DOF in index or middle finger, 1 active DOF and 1 passive DOF in thumb. The 5 active DOF is driven by motors. The transmission consists of screw nut and multi-link mechanism. We control the device through a typical secondary control system. As this device is designed to help patients not only regain the range of flexion/extension but also complete some typical simple grasping movements. To substantiate the feasibility, an experiment has been carried out. Finally, Suggestions for improvement are given.