NEW METHOD FOR VIBRATION MEASUREMENT AND CONTROL OF MOVING WIRE

ＮＥＷＭＥＴＨＯＤＦＯＲＶＩＢＲＡＴＩＯＮＭＥＡＳＵＲＥＭＥＮＴＡＮＤＣＯＮＴＲＯＬＯＦＭＯＶＩＮＧＷＩＲＥＨｕＸｕａｎｌｉ；ＣｈｅｎＴｉａｎｎｉｎｇ；ＴａｎｇＹｏｎｇｊｉｅ；ＺｈａｎｇＳｈｅｎｇｂｉ（Ｘｉ＇ａｎＪｉａｏｔｏｎｇＵｎｉｖｅｒｓｉｔｙ）...     

IMPROVING ACCURACY OF CNC MACHINE TOOLS THROUGH COMPENSATION FOR THERMAL ERRORS

ＩＭＰＲＯＶＩＮＧＡＣＣＵＲＡＣＹＯＦＣＮＣＭＡＣＨＩＮＥＴＯＯＬＳＴＨＲＯＵＧＨＣＯＭＰＥＮＳＡＴＩＯＮＦＯＲＴＨＥＲＭＡＬＥＲＲＯＲＳＬｉＳｈｕｈｅＺｈａｎｇＹｉｑｕｎＹａｎｇＳｈｉｍｉｎＺｈａｎｇＧｕｏｘｉｏｎｇＴｉａｎｊｉｎＵｎｉｖｅｒｓｉｔ...     

METHOD OF ENHANCING THE POSITIONING ACCURACY FOR NC MACHINE TOOLS

ＭＥＴＨＯＤＯＦＥＮＨＡＮＣＩＮＧＴＨＥＰＯＳＩＴＩＯＮＩＮＧＡＣＣＵＲＡＣＹＦＯＲＮＣＭＡＣＨＩＮＥＴＯＯＬＳＺｈａｎｇＱｉｎｇ；ＬｉｕＹｏｕｗｕ；ＦａｎＪｉｎｗｅｉ；ＷａｎｇＳｈｕｘｉｎ；ＷａｎｇＸｉａｏｓｈｏｎｇ；ＷｕＪｉａｎｈｕａ（Ｔｉａｎｊ...     

ANALYSIS OF ROLLING BY ELASTO-PLASTIC FINITE DEFORMATION CONTACT BOUNDARY ELEMENT METHOD

ＡＮＡＬＹＳＩＳＯＦＲＯＬＬＩＮＧＢＹＥＬＡＳＴＯＰＬＡＳＴＩＣＦＩＮＩＴＥＤＥＦＯＲＭＡＴＩＯＮＣＯＮＴＡＣＴＢＯＵＮＤＡＲＹＥＬＥＭＥＮＴＭＥＴＨＯＤＨｕａｎｇＱｉｎｇｘｕｅＳｈｅｎＧｕａｎｇｘｉａｎＸｉａｏＨｏｎｇＴａｉｙｕａｎＨｅａｖｙＭａ...     

DIFFERENTIAL 3ω METHOD FOR THERMAL MEASUREMENTS

The 3ω technique has been applied to measure thermal properties of thin films and suspended wires. In this article, we report the implementation and technical design of a 3ω system to measure the thermal conductivity in small dimension structures. Alternating current is applied to a line heater that dissipates power and varies its resistance. The 3ω voltage drop across the heater provides information that determines the thermal properties of the heater or of the adjacent material. A differential bridge is used to subtract the first harmonic voltage and systematic noise. We introduce the use of a synchronous detector associated with the differential bridge to obtain the in-phase and out-of-phase components of the third harmonic signal. The combination improves the bridge method for a broad range of frequency analysis that permits either thermal conductivity and/or heat capacity measurements.     

SHARED CONTROL METHOD FOR COMBINATION STATE CONVERSION OF ELECTRO－MECHANICAL EQUIPMENT

ＳＨＡＲＥＤＣＯＮＴＲＯＬＭＥＴＨＯＤＦＯＲＣＯＭＢＩＮＡＴＩＯＮＳＴＡＴＥＣＯＮＶＥＲＳＩＯＮＯＦＥＬＥＣＴＲＯ－ＭＥＣＨＡＮＩＣＡＬＥＱＵＩＰＭＥＮＴＳＨＡＲＥＤＣＯＮＴＲＯＬＭＥＴＨＯＤＦＯＲＣＯＭＢＩＮＡＴＩＯＮＳＴＡＴＥＣＯＮＶＥＲＳＩＯＮ...     

ANALYSIS OF METHOD FOR DETERMINING AZIMUTH OF PRINCIPAL AXIS OF INERTIA BASED ON DYNAMIC BALANCE MEASUREMENT

The dynamic balance quality of a rotating object is an important factor to maintain the stability and accuracy for motion. The azimuth of the principal axis of inertia is a major sign of dynamic balance. A usual method is measuring moment of inertia matrix relative to some base coordinates on a rotary inertia machine so as to calculate the azimuth of principal axis of inertia. By using the measured unbalance results on the two trimmed planes on a vertical hard bearing double-plane dynamic balancing machine, the dimension and direction of couple unbalance can be found. An azimuth angle formula for the principal axis of inertia is derived and is solved by using unbalance quantities. The experiments indicate that method based on dynamic balancing measurement is proved rational and effective and has a fine precision.     

NEW VISUAL METHOD FOR FREE-FORM SURFACE RECONSTRUCTION

0 INTRODUCTION(Reverse engineering has been strongly connected with modern design, and plays an important role in new product development. By now, to get a digital geometric model of an object, a coordinate measurement machine (CMM) and some sorts of CAD software are indispensable. This is a expensive and strenuous way to reverse engineering. In fact, reverse engineering is broadly used in many other fields, such as advertisement, entertainment and virtual reality (VR), etc. Looking fo…     

PRESSURE FORCE CONTROL FOR FABRICATION OF PLASTIC MICROFLUIDIC CHIPS WITH HOT EMBOSSING METHOD

A pressure force control system for hot embossing of microfluidic chips is designed with a moment motor and a ball bearing lead screw. Based on the numeric PID technique, the algorithm of pulsant integral accelerated PID control is presented and the negative effects of nonlinearity from friction, clearance and saturation are eliminated. In order to improve the quick-response characteristic, independent thread technique is adopted. The method of pressure force control based on pulsant integral accelerated PID control and independent thread technique is applied with satisfactory control performance.     

CONTROL SYSTEM OF MAGNETIC BEARINGS BASED ON LINEAR QUADRATIC METHOD OF OPTIMAL CONTROL STRATEGY

A state equation for radical 4-degree-of-freedom active magnetic bearings is built, and the approach on how to use linear quadratic method of optical control theory to design a centralized and decentralized parameters control system is introduced, and also Matlab language is used to simulate and analyze. The simulation results have proved that the differences are small between centralized parameters and decentralized parameters control system. The conclusions of experiments have shown that decentralized controllers designed from optimal state feedback theory meet the requirements of active magnetic bearing system. The vibration amplitude of the rotor is about 20 μm when the speed of the rotor runs between 0 to 60 000 r/min. This method may be used in the study and design of controllers of magnetic bearings.     

SENSITIVITY ANALYSIS FOR ROLLING PROCESS BASED ON SUPPORT VECTOR MACHINE

A method for the calculation of the sensitivity factors of the rolling process has been obtained by differentiating the roll force model based on support vector machine. It can eliminate the algebraic loop of the analytical model of the rolling process. The simulations in the first stand of five stand cold tandem rolling mill indicate that the calculation for sensitivities by this proposed method can obtain a good accuracy, and an appropriate adjustment on the control variables determined directly by the sensitivity has an excellent compensation accuracy. Moreover, the roll gap has larger effect on the exit thickness than both front tension and back tension, and it is more efficient to select the roll gap as the control variable of the thickness control system in the first stand.     

NEW CRITERION OF DEGREE OF FREEDOM FOR PLANE MECHANISM

ＮＥＷＣＲＩＴＥＲＩＯＮＯＦＤＥＧＲＥＥＯＦＦＲＥＥＤＯＭＦＯＲＰＬＡＮＥＭＥＣＨＡＮＩＳＭ￥ＹｅＭａｏｄｏｎｇ；ＹａｎｇＳｈｕｇｕｏ（ＴａｉｙｕａｎＵｎｉｖｅｒｓｉｔｙｏｆＴｅｃｈｎｏｌｏｇｙ）Ａｂｓｔｒａｃｔ：Ａｎｅｗｃｒｉｔｅｒｉｏｎｏｆｄｅｇ...     

ON DESIGN METHOD OF THE PRECISION CAM PROFILE WITH RANDOM PROCESSING ERRORS

Based on probability and statistic, a design method of precision cam profile concerning the influence of random processing errors is advanced. Combining the design with the process, which can be used to predict that cam profiles will be successfully processed or not in the design stage, design of the cam can be done by balancing the economization and reliability. In addition, an fuzzy deduction method based on Bayers formula is advanced to estimate processing reasonable of the designed precision cam profile, and it take few samples.     

OPTIMAL CONTROL PRINCIPLE OF PROFILE ERRORS FOR MACHINING OF CYLINDER CAM

ＯＰＴＩＭＡＬＣＯＮＴＲＯＬＰＲＩＮＣＩＰＬＥＯＦＰＲＯＦＩＬＥＥＲＲＯＲＳＦＯＲＭＡＣＨＩＮＩＮＧＯＦＣＹＬＩＮＤＥＲＣＡＭＺｈａｎｇＹｉｔｏｎｇ，Ｌｕｌｉｎｇ，ＹｉｎＭｉｎｇｆｕ，ＹａｎｓｈａｎＵｎｉｖｅｒｓｉｔｙＳｈａｎｄｏｎｇＥｎｇｉｎｅｅｒ...     

POWER FLOW ANALYSIS FOR A NEW ISOLATION SYSTEM-FLEXIBLE FLOATING RAFT

ＰＯＷＥＲＦＬＯＷＡＮＡＬＹＳＩＳＦＯＲＡＮＥＷＩＳＯＬＡＴＩＯＮＳＹＳＴＥＭ－ＦＬＥＸＩＢＬＥＦＬＯＡＴＩＮＧＲＡＦＴＰＯＷＥＲＦＬＯＷＡＮＡＬＹＳＩＳＦＯＲＡＮＥＷＩＳＯＬＡＴＩＯＮＳＹＳＴＥＭ－ＦＬＥＸＩＢＬＥＦＬＯＡＴＩＮＧＲＡＦＴＸｉｏｎｇ...     

STATIONARY DYNAMIC CHARACTERISTICS ANALYSIS OF NEW SQUEEZED FILM DAMPER

Recur to multi-hole and better elastic characteristics of metal rubber (MR), a new squeezed film damper with MR (SFD/MR) throttle ring installed on the end of MR and MR damping ring installed on the radial direction of MR is implemented. Based on the D'alembert principle, a locomotion equation and the mathematical model of stationary response of SFD/MR system is put forward. It proves that the SFD/MR has better ability to resist unbalance loads than the traditional SFD after the stationary dynamic characteristics of the traditional SFD and the new SFD/MR are researched.     

METHOD FOR PRECISE CALCULATION OF ROOT STRESS OF SPIRAL BEVEL GEARS

ＭＥＴＨＯＤＦＯＲＰＲＥＣＩＳＥＣＡＬＣＵＬＡＴＩＯＮＯＦＲＯＯＴＳＴＲＥＳＳＯＦＳＰＩＲＡＬＢＥＶＥＬＧＥＡＲＳＭＥＴＨＯＤＦＯＲＰＲＥＣＩＳＥＣＡＬＣＵＬＡＴＩＯＮＯＦＲＯＯＴＳＴＲＥＳＳＯＦＳＰＩＲＡＬＢＥＶＥＬＧＥＡＲＳＣｈｅｎＬｉａｎｇｙｕ...     

CORRELATION TESTING METHOD FOR DETE-RMINING DISTRIBUTION OF MEASUREMENT DATA

ＣＯＲＲＥＬＡＴＩＯＮＴＥＳＴＩＮＧＭＥＴＨＯＤＦＯＲＤＥＴＥ－ＲＭＩＮＩＮＧＤＩＳＴＲＩＢＵＴＩＯＮＯＦＭＥＡＳＵＲＥＭＥＮＴＤＡＴＡＺｈｕＱｉｏｎｇｃｈａｎｇ，ＨｕａｎｇＹｉｈｏｎｇＳｏｕｔｈＣｈｉｎａＵｎｉｖｅｒｓｉｔｙｏｆＴｅｃｈｎｏｌｏｇｙ...     

RESEARCH ON MODELING AND CHARACTERISTICS OF THE SPINDLE DYNAMIC COUPLING ABSORBERING SYSTEM OF A SUPER－PRECISION SURFACE GRINDING MACHINE

The bearing is described by constrain matrix, and the spindle system of a NC surface grinding machine is simplified as elastic-coupling beam, then modal synthesis method is used to establish the dynamic model of beam. Moreover, the response of the end of rotor is analyzed, and the natural frequency, principle mode and other dynamic characteristics of the coupling system are studied, the law of bearing stiffness to coupling frequency and amplitude of rotor is also found. Finally, according to the actual condition, a dynamic absorber is designed. The simulation and experimental results show that the amplitude of spindle can be declined effectively when the dynamic absorber is attached.     

RESEARCH ON THE PERFORMANCE OF NEW TYPE OF PROPORTIONAL PESSURE AND FLOW CONTROL VALVE

A new closed loop flow controlling principle through correcting the valve's opening area while load pressure is changing is carried out. Further more a principle using only one proportional valve to compound control pressure and flow is suggested. By using very simple proportional throttle valve in structure, the functions that five kinds of proportional valves or any two of them combined possess can be complimented. After analyzing, comparing, and testing the dynamic and static characteristics of valve with different controlling principles and main valve structure styles, the optimized structure styles and control methods are achieved.