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An Optimal Feed interpolator Based on G^2 Continuous Bézier Curves for High-Speed Machining of Linear Tool Path

Chinese Journal of Mechanical Engineering 2019年第3期32卷 109-118页

作者： Yongqiao Jin Sheng Zhao Yuhan Wang Shanghai Spaceflight Precision Machinery Institute Shanghai 201600China State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong UniversityShanghai 200240China

A numerical control (NC) tool path of digital CAD model is widely generated as a set of short line segments in machining. However, there are three shortcomings in the linear tool path, such as discontinuities of tangency and curvature, huge number of line segments, and short lengths of line segments. These disadvantages hinder the development of high speed machining. To smooth the linear tool path and improve machining efficiency of short line segments, this paper presents an optimal feed interpolator based on G^2 continuous Bézier curves for the linear tool path. First, the areas suitable for fitting are screened out based on the geometric characteristics of continuous short segments (CSSs). CSSs in every area are compressed and fitted into a G^2 Continuous Bézier curve by using the least square method. Then a series of cubic Bézier curves are generated. However, the junction between adjacent Bézier curves is only G^0 continuous. By adjusting the control points and inserting Bézier transition curves between adjacent Bézier curves, the G^2 continuous tool path is constructed. The fitting error is estimated by the second-order Taylor formula. Without iteration, the fitting algorithm can be implemented in real-time environment. Second, the optimal feed interpolator considering the comprehensive constraints (such as the chord error constraint, the maximum normal acceleration, servo capacity of each axis, etc.) is proposed. Simulation and experiment are conducted. The results shows that the proposed method can generate smooth path, decrease the amount of segments and reduce machining time for machining of linear tool path. The proposed research provides an effective method for high-speed machining of complex 2-D/3-D profiles described by short line segments.

关键词： G^2 continuous path Least square method High-speed machining Continuous short segments Optimal feed interpolator Data compression

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Experimental and numerical investigation on surface quality for two-point incremental sheet forming with interpolator

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Chinese Journal of Aeronautics 2020年第10期33卷 2794-2806页

作者： Xiaoqiang LI Kai HAN Xu SONG Haibo WANG Dongsheng LI Yanle LI Qing LI School of Mechanical Engineering and Automation Beihang UniversityBeijing 100083China School of Mechanical and Materials Engineering North China University of TechnologyBeijing 100144China Key Laboratory of High Efficiency and Clean Mechanical Manufacture Ministry of EducationSchool of Mechanical EngineeringShandong UniversityJinan 250061China Materials Science Branch of Chinalco Research Institute Chinalco Materials Application Research Institute Co.LTDBeijing 102209China

The unsatisfied surface quality seriously impedes the wide application of incremental sheet forming(ISF)in industrial *** a novel approach,the interpolator method is a promising strategy to enhance the surface quality in ***,the mechanism for the improvement of surface quality and the influence of interpolator properties on surface roughness are not well *** this paper,the influences of process variables(*** diameter,step size and thickness of interpolators)on the forming process(*** roughness,forming force and geometric error)are investigated through a systematic experimental approach of central composite design(CCD)in two-point incremental sheet forming(TPIF).It is obtained that the increase in thickness of interpolators decreases the surface roughness in direction vertical to the tool path while increases the surface roughness in direction horizontal to the tool ***,the combined influence between thickness of interpolators and process parameters(tool diameter and step size)is ***,the placement of interpolator has little influence on the effective forming force of *** addition,the geometric error enlarges with the increase of step size and thickness of interpolator while decreases firstly and then increase with an increase in tool ***,the influencing mechanism of the interpolator method on surface quality can be attributed to the decrease of thecontact pressure due to the increase of contact area with the unchanged contact ***,the interpolator method eliminates the sliding friction on the surface of blank due to the stable relative position between the blank and the interpolator.

关键词： Forming force Geometric error interpolator Process parameter Surface quality Two-point incremental sheet forming

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A Universal Approach to Designing an Image interpolator with an Image Smoothing Filter

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Journal of Signal and Information Processing 2019年第1期10卷 12-18页

作者： Min-Cheng Pan Department of Electronic Engineering Tungnan University Taiwan

A number of conventional interpolation techniques have been proposed. However, it seems that there do not exist good criteria for the design of optimal linear interpolators. Also, such an interpolator can hardly provide a satisfactory solution for interpolating noisy images. In this paper, the novelty of this research is that a universal approach is proposed to design an image interpolator with any one image smoothing filter, thereby not only interpolating a down-sampled image but also preserving the characteristics of the performing filtering.

关键词： interpolator Smoothing Filter Down-Sampled Image

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Design and Implementation of a Novel Area-Efficient interpolator

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Journal of Semiconductors 2006年第7期27卷 1164-1169页

作者：彭云峰孔德睿周锋复旦大学专用集成电路与系统国家重点实验室上海201203

This paper presents the design considerations and implementation of an area-efficient interpolator suitable for a delta-sigma D/A converter. In an effort to reduce the area and design complexity, a method for designing an FIR filter as a tapped cascaded interconnection of identical subfilters is modified. The proposed subfilter structure further minimizes the arithmetic number. Experimental results show that the proposed interpolator achieves the design specification,exhibiting high performance and hardware efficiency,and also has good noise rejection capability. The interpolation filter can be applied to a delta-sigma DAC and is fully functional.

关键词： delta-sigma digital-to-analog converter interpolator halfband filter

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Adaptive fuzzy controllers based on variable universe

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Science China(Technological Sciences) 1999年第1期42卷 10-20页

作者：李洪兴 Department of Mathematics Beijing Normal University Beijing China

Adaptive fuzzy controllers by means of variable universe are proposed based on interpolation forms of fuzzy control. First, monotonicity of control rules is defined, and it is proved that the monotonicity of interpolation functions of fuzzy control is equivalent to the monotonicity of control rules. This means that there is not any contradiction among the control rules under the condition for the control rules being monotonic. Then structure of the contraction-expansion factor is discussed. At last, three models of adaptive fuzzy control based on variable universe are given which are adaptive fuzzy control model with potential heredity, adaptive fuzzy control model with obvious heredity and adaptive fuzzy control model with successively obvious heredity.

关键词： fuzzy control variable universe contraction-expansion factor interpolator adaptive fuzzy control.

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A 750 MHz semi-digital clock and data recovery circuit with 10^(-12) BER

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Journal of Semiconductors 2011年第12期32卷 139-143页

作者：韦雪明王忆文李平罗和平 State Key Laboratory of Electronic Thin Films and Integrated Devices University of Electronic Science & Technology of China

A semi-digital clock and data recovery （CDR） is presented. In order to lower CDR trace jitter and decrease loop latency, an average-based phase detection algorithm is adopted and realized with a novel circuit. Implemented in a 0.13 μm standard 1PSM CMOS process, our CDR is integrated into a high speed serial and de-serial （SERDES） chip. Measurement results of the chip show that the CDR can trace the phase of the input data well and the RiMS jitter of the recovery clock in the observation pin is 122 ps at 75 MHz clock frequency, while the bit error rate of the recovery data is less than 10 × 10^-12.

关键词： clock and data recovery interpolator SERDES

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A Reference-Pulse Generator for Motion Control System

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Intelligent Control and Automation 2014年第3期5卷 111-119页

作者： Nguyen Hoang Giap Jin-Ho Shin Won-Ho Kim Department of Intelligent System Engineering Graduate School of Dong-eui University Busan Korea Department of Mechatronics Engineering Dong-eui University Busan Korea

This paper introduces a reference-pulse interpolator motion control system, which can be applied for computer numerical control (CNC) machine tools. The interpolation is calculated in DSP and the independent pulse generator modules are performed in FPGA, which can generate precise reference velocity profile and eliminate the path error of reference pulse interpolation. The proposed methodology has many advantages over existing reference-pulse interpolator controller, such as: real-time, extensibility, high flexibility and high precision motion profile planning.

关键词： Motion Control Reference-Pulse interpolator CNC Machine

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Integrated Delta-Sigma 1.5bit Power DAC with 100dB Dynamic Range

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Journal of Semiconductors 2007年第5期28卷 651-654页

作者：李丹梁嘉义洪志良许刚复旦大学专用集成电路与系统国家重点实验室上海201203 捷顶微电子有限公司上海201203

A stereo 1.5bit delta-sigma digital-analog converter （△∑ DAC） integrated with a filterless class D power amplifier is introduced. It consumes no static power, and its maximum output power is 436mW with an 8Ω load. Its output dynamic range exceeds 100dB. The circuit is implemented with a TSMC 0. 18μm process. The die area is 0. 28mme. The supply voltage is 1. gV for the digital part and 3.3V for class D.

关键词： delta-sigma DAC filterless class D power amplifier interpolator power DAC

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EXPERIMENTATION AND NUMERICAL SIMULATION OF THE MANUFACTURE OF AN ELLIPSOIDAL WORKPIECE BY MULTI-POINT SANDWICH FORMING

EXPERIMENTATION AND NUMERICAL SIMULATION OF THE MANUFACTURE ...

引用

International Technology and Innovation Conference 2006

作者： T A Dean School of Materials Science and Technology Harbin Institute of Technology

＜正＞To significantly reduce the time and cost of tooling development for sheet metal parts, a new reconfigurable die forming, the multi-point sandwich forming （MPSF） is being developed for parts with various curvatures, in small batch quantities. In this process, the die surface can be changed by adjusting the height of the pins in the lower die. Some elastic polyurethane pads are used as an upper die. To enable parts of good surface quality to be formed, an elastic interpolator and die sheet also are used in the process. The arrangement of each component of the tool set has a sandwich like structure, and therefore this process is called multi-point sandwich forming. To investigate this process, in the work described in this paper the die with ellipsoidal surface was chosen to manufacture workpieces in this paper. The effect of the thickness of interpolator on the height of workpiece dimples and forming errors along two typical sections of workpiece was investigated through experiment and the commercial FE simulation software ABAQUS was used to investigate the loading process and springback after unloading. Simulation enabled an explanation to be obtained as to why dimples occur in the middle edges of a workpiece. Also the final shape of the workpiece calculated by FE simulation was in good agreement with the experiment of result.

关键词： Multi-point sandwich forming interpolator ellipsoid springback sheet forming.

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EXPERIMENTATION AND NUMERICAL SIMULATION OF THE MANUFACTURE OF AN ELLIPSOIDAL WORKPIECE BY MULTI-POINT SANDWICH FORMING

EXPERIMENTATION AND NUMERICAL SIMULATION OF THE MANUFACTURE ...

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2006年中国机械工程学会年会暨中国工程院机械与运载工程学部首届年会

作者： T.A.Dean School of Materials Science and Technology Harbin Institute of Technology

To significantly reduce the time and cost of tooling development for sheet metal parts, a new reconfigurable die forming, the multi-point sandwich forming (MPSF) is being developed for parts with vari

关键词： Multi-point sandwich forming interpolator ellipsoid springback sheet forming.

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