Based on the evaluation of dynamic performance for feed drives in machine tools, this paper presents a two-stage tuning method of servo parameters. In the first stage, the evaluation of dynamic performance, parameter ...Based on the evaluation of dynamic performance for feed drives in machine tools, this paper presents a two-stage tuning method of servo parameters. In the first stage, the evaluation of dynamic performance, parameter tuning and optimization on a mechatronic integrated system simulation platform of feed drives are performed. As a result, a servo parameter combination is acquired. In the second stage, the servo parameter combination from the first stage is set and tuned further in a real machine tool whose dynamic performance is measured and evaluated using the cross grid encoder developed by Heidenhain GmbH. A case study shows that this method simplifies the test process effectively and results in a good dynamic performance in a real machine tool.展开更多
In order to improve the measurement-precision of the gyro,the gyro experiment is completed based on gyro servo technology.The error sources of gyro servo technology are analyzed in the process of measurement,and the i...In order to improve the measurement-precision of the gyro,the gyro experiment is completed based on gyro servo technology.The error sources of gyro servo technology are analyzed in the process of measurement,and the impact of these error sources on measurement is evaluated.To eliminate interference signal existing in the sampled data of the measurement,a modified wavelet threshold filtering method is presented.The results of the simulation and measurement show that the estimation-precision of the proposed method is improvement remarkably compared with the fast Fourier transform method,and the calculation work is reduced compared with the conventional wavelet threshold filtering methods,furthermore,the phenomenon of a common threshold of ＂killing＂ is solved thoroughly.展开更多
This paper presents an improved support vector machine （SVM） algorithm, which employs invariant moments-based edge extraction to obtain feature attribute. A heuristic attribute reduction algorithm based on rough set...This paper presents an improved support vector machine （SVM） algorithm, which employs invariant moments-based edge extraction to obtain feature attribute. A heuristic attribute reduction algorithm based on rough set＇s discernible matrix is proposed to identify and classify micro-targets. To avoid the complicated calibration for intrinsic parameters of camera, an improved Broyden＇s method is proposed to estimate the image Jacobian matrix which employs Chebyshev polynomial to construct a cost function to approximate the optimization value. Finally, a visual controller is designed for a robotic micromanipulation system. The experiment results of micro-parts assembly show that the proposed methods and algorithms are effective and feasible.展开更多
基金This paper is supported by the Major State Basic Research Development Program of China under Grant No2005CB724101the Key Items Program of International Science and Technology Cooperation of China under Grant No2003DF000021
文摘Based on the evaluation of dynamic performance for feed drives in machine tools, this paper presents a two-stage tuning method of servo parameters. In the first stage, the evaluation of dynamic performance, parameter tuning and optimization on a mechatronic integrated system simulation platform of feed drives are performed. As a result, a servo parameter combination is acquired. In the second stage, the servo parameter combination from the first stage is set and tuned further in a real machine tool whose dynamic performance is measured and evaluated using the cross grid encoder developed by Heidenhain GmbH. A case study shows that this method simplifies the test process effectively and results in a good dynamic performance in a real machine tool.
基金supported by the National Basic Research Program of China (973 Program) (973-61334)
文摘In order to improve the measurement-precision of the gyro,the gyro experiment is completed based on gyro servo technology.The error sources of gyro servo technology are analyzed in the process of measurement,and the impact of these error sources on measurement is evaluated.To eliminate interference signal existing in the sampled data of the measurement,a modified wavelet threshold filtering method is presented.The results of the simulation and measurement show that the estimation-precision of the proposed method is improvement remarkably compared with the fast Fourier transform method,and the calculation work is reduced compared with the conventional wavelet threshold filtering methods,furthermore,the phenomenon of a common threshold of ＂killing＂ is solved thoroughly.
基金supported by National Natural Science Foundation of China (No.60873032)National High Technology Research and Development Program of China (863 Program) (No.2008AA8041302)
文摘This paper presents an improved support vector machine （SVM） algorithm, which employs invariant moments-based edge extraction to obtain feature attribute. A heuristic attribute reduction algorithm based on rough set＇s discernible matrix is proposed to identify and classify micro-targets. To avoid the complicated calibration for intrinsic parameters of camera, an improved Broyden＇s method is proposed to estimate the image Jacobian matrix which employs Chebyshev polynomial to construct a cost function to approximate the optimization value. Finally, a visual controller is designed for a robotic micromanipulation system. The experiment results of micro-parts assembly show that the proposed methods and algorithms are effective and feasible.
基金Supported by Natural Science Foundation of Tianjin （07JCY- BJC05400）, Opening Project of National Laboratory of Industrial Control Technology of Zhejiang University （0708001）, Program for New Century Excellent Talents in University （NCET-06-0210）
