Advanced Materials Research Vols. 503-504

Abstract: Based on the magnetic suspension theory, this paper has proposed a kind of suspension-type jacquard needle driving principle, and designed its 3-dimension model method. By making finite element analysis on suspension-type needles, analyzing the experimental data and designing the structure, we can get the relationship among related parameters under conditions of different permanent-magnet thickness and air gaps, which can provide criteria in theory and application for designing on new needle driving principle, control system and needle.

Abstract: Deep hole processing system resonance test devices can accurately and quickly find the whole system resonance frequency, for use of negative pressure device system to processing components provided a convenient, makes the precision of parts is further improved.

Abstract: Rotary torque is one of the important parameters of the bogie. A scheme of the rotary torque test for the bogie was put forward, and the homogeneous matrix based on the Euler angle was introduced, the model of inverse pose of the slewing platform was built. Also, it implemented the real-time solution by means of simulink, and fitted the curve of hydraulic cylinder expansion amount and time by use of the MATLAB curve fitting toolbox. The method that took the motion curves of the actuators as the control input is put forward, which was of great value and laid the foundation for the test of rotary torque.

Abstract: In order to determine the，a test bench for the natural vibration characteristics of the bogie suspension was put forward. Firstly the natural vibration characteristics structure composition and the testing principle was introduced, the sine sweep incentive was simulated, and the inverse kinematics solution model and the real-time solution model were developed. The Comparison of the simulation result and the geometric theory results was carried out, proving the accuracy of the inverse kinematics solution model and the simulation model.

Abstract: In long-period running of switch cabinet, the temperature of contact points will be rose by the big contact resistance, poor contact and longtime overloading. Overheat can cause oxidation of contact points and the increasing of contact resistance, and then the contact may be generated the spark and arc discharge. That is a bad circle. So the temperature of contact points can affect the reliability of switch cabinet. For detecting the temperature of contacts and the switch cabinet’s environment in Yanjin transformer substation, we design an Insulated FBG temperature sensor. The surveys of upper reaches indicate that the temperature of moving contact A gets the maximum 32.98°C Aug.20, 2011, the temperature of stationary contact A gets the minimum 5.75°C, and the change temperature between contacts and environment gets the maximum 2.82°C. According to relevant state regulations, the contact’s temperature of 70 °C and temperature’s changes of 35 °C in the case of environment’s temperature below 40°C are Alarm threshold value of switch cabinet.

Abstract: In this paper, the resistance values of five different fineness cotton were tested under different moisture conditions, and the relationship among fiber fineness, moisture regain and its resistance were studied. With the increase of the moisture regain, the mass specific resistance and volume resistance decrease in an exponential trend, and the inflection point of the curve is located at the moisture regain value of 3%. The fiber fineness has little effect on the resistance.

Abstract: The response spectrum of the nonlinear vibration isolation system under harmonic excitation is a continuous one when chaos occurs. This feature is utilized to eliminate or reduce the line spectrum in the radiated noise of the marine vessel. A nonlinear feedback controller was designed with the active control synchronization technology, and the projective chaos synchronization (PCS) was realized with different chaotic driving system. Simulation results show that the spectrum can be attenuated greatly through changing the ratio factor.

Abstract: Based on the traits of the four-wheel drive EV, a self-adaptive Kalman filter was applied to gain the information of vehicle velocity and traction forces on four wheels. With the estimated vehicle velocity and the driving forces on four wheels, the slope k of the curves of adhesion coefficient versus slip rate could be calculated and consequently the road adhesion condition could be accurately identified. Through calculating the difference between the estimated slope k with the optimized slope k as a control reference, the output torques of the motors were adjusted instantaneously to improve the using rate of the adhesion as well as the rationality of the traction control strategy. Simulation results illustrate that whether on high adhesion or low adhesion roads the vehicle is passing, the strategy can estimate the k effectively.

Abstract: Through testing the errors of spur gear and helical gears, transmission error curve of non-grinding gear is drawn. The effect factors on gear transmission error are found. The transmission error effect factors of all kinds of gear high-low frequency are analyzed. It is obtained that gear kinematic error is the evaluating guideline of transmission precision. Experimental results shows that error of gear axial offset and gear frequency period have less effect on gear transmission kinematic error. While gear backlash and face width direction error have more obvious effect on kinematic error. The results provides reasonable theory basis for determining gear cutting precision.

Abstract: The exciting input signals of the parts in a fatigue life test rig for ball with three point contact and the system’s output signals were analyzed by auto-correlation and cross-correlation with MATLAB software, which eliminated the impact of noise to a certain extent and got the response signals of same frequencies caused by exciting input signals. Finally, the result showed that the text rig was linear by coherent function analysis, which provided the theory basis for modal and dynamic analysis further.