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Efficient algorithm for 3D bimodulus structures 认领 引用 被引量：7
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作者 Qinxue Pan Jianlong Zheng Pihua Wen 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2020年第1期143-159,共17页
The bimodulus material is a classical model to describe the elastic behavior of materials with tension-compression asymmetry.Due to the inherently nonlinear properties of bimodular materials,traditional iteration meth... The bimodulus material is a classical model to describe the elastic behavior of materials with tension-compression asymmetry.Due to the inherently nonlinear properties of bimodular materials,traditional iteration methods suffer from low convergence efficiency and poor adaptability for large-scale structures in engineering.In this paper,a novel 3D algorithm is established by complementing the three shear moduli of the constitutive equation in principal stress coordinates.In contrast to the existing 3D shear modulus constructed based on experience,in this paper the shear modulus is derived theoretically through a limit process.Then,a theoretically self-consistent complemented algorithm is established and implemented in ABAQUS via UMAT;its good stability and convergence efficiency are verified by using benchmark examples.Numerical analysis shows that the calculation error for bimodulus structures using the traditional linear elastic theory is large,which is not in line with reality. 展开更多
关键词 Elastic theory Bimodulus material 3D complemented algorithm Finite element method Generalized elastic law General 3D shear modulus
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Widely linear UKF constant modulus algorithm for blind adaptive beamforming 认领 引用 被引量：1
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作者 Huaming Qian Ke Liu +2 位作者 Long Li Linchen Qian Junda Ma 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2017年第3期413-423,共11页
Based on a uniform linear array, a new widely linear unscented Kalman filter-based constant modulus algorithm (WL-UKF-CMA) for blind adaptive beamforming is proposed. The new algorithm is designed according to the con... Based on a uniform linear array, a new widely linear unscented Kalman filter-based constant modulus algorithm (WL-UKF-CMA) for blind adaptive beamforming is proposed. The new algorithm is designed according to the constant modulus criterion and takes full advantage of the noncircular property of the signal of interest (SOI), significantly increasing the output signal-to interference-plus-noise ratio (SINR), enhancing the convergence speed and decreasing the steady-state misadjustment. Since it requires no known training data, the proposed algorithm saves a large amount of the available spectrum. Theoretical analysis and simulation results are presented to demonstrate its superiority over the conventional linear least mean square-based CMA (L-LMS-CMA), the conventional linear recursive least square-based CMA (L-RLS-CMA), WL-LMS-CMA, WL-RLS-CMA and L-UKF-CMA. 展开更多
关键词 widely linear filtering blind beamforming noncircular signals constant modulus algorithm unscented Kalman filtering
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Enhanced asphalt dynamic modulus prediction: A detailed analysis of artificial hummingbird algorithm-optimised boosted trees 认领 引用
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作者 Ikenna D.Uwanuakwa Ilham Yahya Amir Lyce Ndolo Umba 《Journal of Road Engineering》 2024年第2期224-233,共10页
This study introduces and evaluates a novel artificial hummingbird algorithm-optimised boosted tree(AHAboosted)model for predicting the dynamic modulus(E*)of hot mix asphalt concrete.Using a substantial dataset from N... This study introduces and evaluates a novel artificial hummingbird algorithm-optimised boosted tree(AHAboosted)model for predicting the dynamic modulus(E*)of hot mix asphalt concrete.Using a substantial dataset from NCHRP Report-547,the model was trained and rigorously tested.Performance metrics,specifically RMSE,MAE,and R2,were employed to assess the model's predictive accuracy,robustness,and generalisability.When benchmarked against well-established models like support vector machines(SVM)and gaussian process regression(GPR),the AHA-boosted model demonstrated enhanced performance.It achieved R2 values of 0.997 in training and 0.974 in testing,using the traditional Witczak NCHRP 1-40D model inputs.Incorporating features such as test temperature,frequency,and asphalt content led to a 1.23%increase in the test R2,signifying an improvement in the model's accuracy.The study also explored feature importance and sensitivity through SHAP and permutation importance plots,highlighting binder complex modulus|G*|as a key predictor.Although the AHA-boosted model shows promise,a slight decrease in R2 from training to testing indicates a need for further validation.Overall,this study confirms the AHA-boosted model as a highly accurate and robust tool for predicting the dynamic modulus of hot mix asphalt concrete,making it a valuable asset for pavement engineering. 展开更多
关键词 Asphalt Dynamic modulus Prediction Artificial hummingbird algorithm Boosted tree
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Algorithmic tangent modulus at finite strains based on multiplicative decomposition 认领 引用
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作者 李朝君 冯吉利 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2014年第3期345-358,共14页
The algorithmic tangent modulus at finite strains in current configuration plays an important role in the nonlinear finite element method. In this work, the exact tensorial forms of the algorithmic tangent modulus at ... The algorithmic tangent modulus at finite strains in current configuration plays an important role in the nonlinear finite element method. In this work, the exact tensorial forms of the algorithmic tangent modulus at finite strains are derived in the principal space and their corresponding matrix expressions are also presented. The algorithmic tangent modulus consists of two terms. The first term depends on a specific yield surface, while the second term is independent of the specific yield surface. The elastoplastic matrix in the principal space associated with the specific yield surface is derived by the logarithmic strains in terms of the local multiplicative decomposition. The Drucker-Prager yield function of elastoplastic material is used as a numerical example to verify the present algorithmic tangent modulus at finite strains. 展开更多
关键词 algorithmic tangent modulus matrix expression finite strain multiplicative decomposition
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BLIND EQUALIZATION OF MIMO SYSTEMS BASED ON ORTHOGONAL CONSTANT MODULUS ALGORITHM 认领 引用 被引量：1
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作者 Shi Kun Zhang Xudong 《Journal of Electronics(China)》 2006年第2期181-183,共3页
This paper investigates adaptive blind source separation and equalization for Multiple Input Multiple Output (MIMO) systems. To effectively recover input signals, remove Inter-Symbol Interference (ISI) and suppress In... This paper investigates adaptive blind source separation and equalization for Multiple Input Multiple Output (MIMO) systems. To effectively recover input signals, remove Inter-Symbol Interference (ISI) and suppress Inter-User Interference (IUI), the array input is first transformed into the signal subspace, then with the derived orthogonality between weight vectors of different input signals, a new orthogonal Constant Modulus Algorithm (CMA) is proposed. Computer simulation results illustrate the promising performance of the proposed method. Without channel identification, the proposed method can recover all the system inputs simultaneously and can be adaptive to channel changes without prior knowledge about signals. 展开更多
关键词 Multiple Input Multiple Output （MIMO） system Blind equalization Constant Modulus Algorithm （CMA） Orthogonality
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Evaluating the Subgrade Reaction Modulus Variations with Soil Grains Shape in Coarse-Grained Soils Using Genetic Algorithm 认领 引用
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作者 Pouya Salari Naser Hafezi Moghaddas +1 位作者 Gholam Reza Lashkaripour Mohammad Ghafoori 《Open Journal of Geology》 CAS 2020年第2期111-123,共13页
Subgrade reaction modulus (Ks) is one of the main factors in evaluating engineering properties of soils for structural calculations and operations. So, many studies have been performed on the effect of other soil geot... Subgrade reaction modulus (Ks) is one of the main factors in evaluating engineering properties of soils for structural calculations and operations. So, many studies have been performed on the effect of other soil geotechnical parameters on it. One is the effect of soil grains shape on engineering properties of soils, especially Ks. The aim of the present research is to evaluate the effect of soil grains shape on Ks for coarse-grained soils of the west of Mashhad, Iran. For this purpose, 20 PLTs were performed on coarse-grained soils of the west of Mashhad and Ks amounts were determined. Then, flakiness and elongation of the samples measured and changes of Ks by soil grain shape were evaluated. The results showed the strength dependency of Ks to grain forms which an increase in flakiness and elongation indices leads to a decrease in Ks. Therefore, it is necessary to reduce Ks estimated form empirical relationships for flaky and elongated soils. So, by writing a genetic algorithm-based program to find the optimal relationship between the grain shape and the subgrade reaction coefficient, a valid equation for correcting the results from previous empirical equations was presented. 展开更多
关键词 Subgrade Reaction Modulus (Ks) Flakiness Test Elongation Test Plate Load Test (PLT) Genetic Algorithm
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ADAPTIVE STEP-SIZE CONSTANT MODULUS ALGORITHM FOR BLIND MULTIUSER DETECTION IN DS-CDMA SYSTEMS 认领 引用
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作者 SunLiping HuGuangrui 《Journal of Electronics(China)》 2004年第1期10-15,共6页
Blind Adaptive Step-size Constant Modulus Algorithm (AS-CMA) for multiuser detection in DS-CDMA systems is presented. It combines the CMA and the concept of variable step-size, uses a second LMS algorithm for the step... Blind Adaptive Step-size Constant Modulus Algorithm (AS-CMA) for multiuser detection in DS-CDMA systems is presented. It combines the CMA and the concept of variable step-size, uses a second LMS algorithm for the step size. It adjusts the step-size according to the minimum output-energy principle within a specified range, thus overcomes the problems of bad effect of fixed step-size LMS algorithm. Compared with Adaptive Step-size LMS (AS-LMS) algoritilrn, through simulations, this algorithm can adapt the changes of the environment, suppress multiple access interference in the dynamic environment and the stability of Signal to Interference Ratio (SIR) is superior to that of AS-LMS. 展开更多
关键词 CDMA Constant modulus algorithm Blind interference suppression
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Machine learning-based prediction of soil compression modulus with application of ID settlement 认领 引用 被引量：22
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作者 Dong-ming ZHANG Jin-zhang ZHANG +2 位作者 Hong-wei HUANG Chong-chong QI Chen-yu CHANG 《Journal of Zhejiang University-SCIENCE A》 SCIE EI CAS CSCD 2020年第6期430-444,共15页
The compression modulus(Es)is one of the most significant soil parameters that affects the compressive deformation of geotechnical systems,such as foundations.However,it is difficult and sometime costly to obtain this... The compression modulus(Es)is one of the most significant soil parameters that affects the compressive deformation of geotechnical systems,such as foundations.However,it is difficult and sometime costly to obtain this parameter in engineering practice.In this study,we aimed to develop a non-parametric ensemble artificial intelligence(AI)approach to calculate the Es of soft clay in contrast to the traditional regression models proposed in previous studies.A gradient boosted regression tree(GBRT)algorithm was used to discern the non-linear pattern between input variables and the target response,while a genetic algorithm(GA)was adopted for tuning the GBRT model's hyper-parameters.The model was tested through 10-fold cross validation.A dataset of 221 samples from 65 engineering survey reports from Shanghai infrastructure projects was constructed to evaluate the accuracy of the new model5 s predictions.The mean squared error and correlation coefficient of the optimum GBRT model applied to the testing set were 0.13 and 0.91,respectively,indicating that the proposed machine learning(ML)model has great potential to improve the prediction of Es for soft clay.A comparison of the performance of empirical formulas and the proposed ML method for predicting foundation settlement indicated the rationality of the proposed ML model and its applicability to the compressive deformation of geotechnical systems.This model,however,cannot be directly applied to the prediction of Es in other sites due to its site specificity.This problem can be solved by retraining the model using local data.This study provides a useful reference for future multi-parameter prediction of soil behavior. 展开更多
关键词 Compression modulus prediction Machine learning(ML) Gradient boosted regression tree(GBRT) Genetic algorithm(GA) Foundation settlement
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Prediction of resilient modulus for subgrade soils based on ANN approach 认领 引用 被引量：13
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作者 ZHANG Jun-hui HU Jian-kun +2 位作者 PENG Jun-hui FAN Hai-shan ZHOU Chao 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第3期898-910,共13页
The resilient modulus(MR)of subgrade soils is usually used to characterize the stiffness of subgrade and is a crucial parameter in pavement design.In order to determine the resilient modulus of compacted subgrade soil... The resilient modulus(MR)of subgrade soils is usually used to characterize the stiffness of subgrade and is a crucial parameter in pavement design.In order to determine the resilient modulus of compacted subgrade soils quickly and accurately,an optimized artificial neural network(ANN)approach based on the multi-population genetic algorithm(MPGA)was proposed in this study.The MPGA overcomes the problems of the traditional ANN such as low efficiency,local optimum and over-fitting.The developed optimized ANN method consists of ten input variables,twenty-one hidden neurons,and one output variable.The physical properties(liquid limit,plastic limit,plasticity index,0.075 mm passing percentage,maximum dry density,optimum moisture content),state variables(degree of compaction,moisture content)and stress variables(confining pressure,deviatoric stress)of subgrade soils were selected as input variables.The MR was directly used as the output variable.Then,adopting a large amount of experimental data from existing literature,the developed optimized ANN method was compared with the existing representative estimation methods.The results show that the developed optimized ANN method has the advantages of fast speed,strong generalization ability and good accuracy in MR estimation. 展开更多
关键词 resilient modulus subgrade soils artificial neural network multi-population genetic algorithm prediction method
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A novel constant modulus array for multiuser detection 认领 引用
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作者 张继东 郑宝玉 傅洪亮 《Journal of Zhejiang University-SCIENCE A》 CAS 2005年第1期38-42,共5页
This paper proposes a new multitarget constant modulus array structure for code division multiple access (CDMA) systems. The new algorithm for the structure is called pre-despreading and wavelet denoising constant mod... This paper proposes a new multitarget constant modulus array structure for code division multiple access (CDMA) systems. The new algorithm for the structure is called pre-despreading and wavelet denoising constant modulus algorithm (D-WD-CMA). In the new algorithm, the pre-despreading is applied to multitarget arrays to remove some multiple access inter- ferences. After that the received signal is subjected to wavelet de-noising to reduce some noise, and used in CMA adaptive iteration for signal separation. Simulation results showed that the proposed algorithm performed better than the traditional CMA algorithm. 展开更多
关键词 Constant modulus algorithm Adaptive array Wavelet de-noising Multiuser detection CDMA
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Recursive Least Squares Semi-blind Beamforming for MIMO Using Decision Directed Adaptation and Constant Modulus Criterion 认领 引用
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作者 Xia Hong Sheng Chen 《International Journal of Automation and computing》 CSCD 2017年第4期442-449,共8页
A new semi-blind adaptive beamforming scheme is proposed for multi-input multi-output （MIMO） induced and spacedivision multiple-access based wireless systems that employ high order phase shift keying signaling. A mi... A new semi-blind adaptive beamforming scheme is proposed for multi-input multi-output （MIMO） induced and spacedivision multiple-access based wireless systems that employ high order phase shift keying signaling. A minimum number of training symbols, very close to the number of receiver antenna elements, are used to provide a rough initial least squares estimate of the beamformer＇s weight vector. A novel cost function combining the constant modulus criterion with decision-directed adaptation is adopted to adapt the beamformer weight vector. This cost function can be approximated as a quadratic form with a closed-form solution, based on which we then derive the recursive least squares （RLS） semi-blind adaptive beamforming algorithm. This semi-blind adaptive beamforming scheme is capable of converging fast to the minimum mean-square-error beamforming solution, as demonstrated in our simulation study. Our proposed semi-blind RLS beamforming algorithm therefore provides an efficient detection scheme for the future generation of MIMO aided mobile communication systems. 展开更多
关键词 Multi-input multi-output （MIMO） space-division multiple-access beamforming semi-blind adaptive algorithm constant modulus criterion decision-directed adaption.
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Protection of Sensitive Messages Based on Quadratic Roots of Gaussians: Groups with Complex Modulus 认领 引用 被引量：1
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作者 Boris S. Verkhovsky 《International Journal of Communications, Network and System Sciences》 2011年第5期287-296,共10页
This paper considers three algorithms for the extraction of square roots of complex integers {called Gaussians} using arithmetic based on complex modulus p + iq. These algorithms are almost twice as fast as the analog... This paper considers three algorithms for the extraction of square roots of complex integers {called Gaussians} using arithmetic based on complex modulus p + iq. These algorithms are almost twice as fast as the analogous algorithms extracting square roots of either real or complex integers in arithmetic based on modulus p, where is a real prime. A cryptographic system based on these algorithms is provided in this paper. A procedure reducing the computational complexity is described as well. Main results are explained in several numeric illustrations. 展开更多
关键词 Complex Modulus Computational Efficiency Cryptographic Algorithm Digital Isotopes Multiplicative Control Parameter Octadic Roots Quartic Roots Rabin Algorithm Reduction of Complexity Resolventa Secure Communication Square Roots
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New multitarget constant modulus array for CDMA systems 认领 引用
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作者 Zhang Jidong Zheng Baoyu 《Journal of Systems Engineering and Electronics》 2006年第2期455-457,共3页
A new mulfitarget constant modulus array is proposed for CDMA systems based on least squares constant modulus algorithm. The new algorithm is called pre-despreading decision directed least squares constant modulus alg... A new mulfitarget constant modulus array is proposed for CDMA systems based on least squares constant modulus algorithm. The new algorithm is called pre-despreading decision directed least squares constant modulus algorithm （D-DDLSCMA）. In the new algorithm, the pre-despreading is first applied for multitarget arrays to remove some multiple access signals, then the despreaded signal is processed by the algorithm which united the constant modulus algorithm and decision directed method. Simulation results illustrate the good performance for the proposed algorithm. 展开更多
关键词 constant modulus algorithm adaptive array multiuser detection code division multiple.
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基于改进随机森林算法的混凝土抗冻性预测 认领 引用
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作者 刘明 杨千葶 王志强 《沈阳建筑大学学报（自然科学版）》 CAS 北大核心 2026年第2期264-271,共8页
为探究混凝土在碳化、冻融循环及硫酸盐侵蚀作用下的抗冻性作用机理,建立适用于混凝土相对动弹性模量的预测模型,提出改进的随机森林(Improved Random Forest,IRF)算法。以水胶比、粉煤灰掺量、聚丙烯纤维掺量、Na2SO4溶液质量分... 为探究混凝土在碳化、冻融循环及硫酸盐侵蚀作用下的抗冻性作用机理,建立适用于混凝土相对动弹性模量的预测模型,提出改进的随机森林(Improved Random Forest,IRF)算法。以水胶比、粉煤灰掺量、聚丙烯纤维掺量、Na2SO4溶液质量分数和抗压强度为输入变量,混凝土相对动弹性模量为输出变量,分别采用BP、SVR、RF及IRF算法建立预测模型,并基于决定系数R2、均方根误差RMSE及平均绝对误差MAE对各模型的预测性能进行对比,结果表明,IRF算法在混凝土相对动弹性模量预测中表现最优,其对应的R2、RMSE及MAE分别为0.965 6、0.026 2及0.022 8。研究发现,抗压强度与混凝土相对动弹性模量呈正相关关系,而水胶比、粉煤灰掺量、聚丙烯纤维掺量及Na2SO4溶液质量分数均与相对动弹性模量呈负相关;当水胶比为0.45、粉煤灰掺量为30%且聚丙烯纤维掺量为1%时,混凝土配合比达到最优。此外,IRF模型通过合理的参数调优,在叶子节点选择上实现了最佳平衡,有效提升了模型的预测精度与泛化能力。 展开更多
关键词 混凝土 相对动弹性模量 随机森林算法 预测模型 抗压强度
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Hybrid Beamforming for MU-MISO Communication via Deep Unfolding 认领 引用
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作者 Liu Dangpeng He Xin He Haoming 《China Communications》 SCIE EI CSCD 2026年第2期260-267,共8页
In hybrid beamforming design using the conventional gradient projection(GP)algorithm,it is common to use a fixed step size,which results in a slow convergence rate and unsatisfactory achievable rate performance.This p... In hybrid beamforming design using the conventional gradient projection(GP)algorithm,it is common to use a fixed step size,which results in a slow convergence rate and unsatisfactory achievable rate performance.This paper employs a deep unfolding algorithm within a small fixed number of iterations to tackle the hybrid beamforming optimization problem.The optimal step size is obtained by combining the conventional GP algorithm with the deep learning technique,and every step in deep learning is explainable.Simulation results show that the proposed deep unfolding algorithm demonstrates a lower computational time and superior achievable rate performance than the conventional GP algorithm. 展开更多
关键词 deep unfolding algorithm hybrid beamforming unit modulus constraint
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A Note on Shor’s Quantum Algorithm 认领 引用 被引量：1
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作者 曹正军 刘丽华 《Journal of Shanghai Jiaotong university(Science)》 EI 2006年第3期368-370,共3页
Shor proposed a polynomial time algorithm for computing the order of one element in a multiplicative group using a quantum computer. Based on Miller’s randomization, he then gave a factorization algorithm. But the al... Shor proposed a polynomial time algorithm for computing the order of one element in a multiplicative group using a quantum computer. Based on Miller’s randomization, he then gave a factorization algorithm. But the algorithm has two shortcomings, the order must be even and the output might be a trivial factor. Actually, these drawbacks can be overcome if the number is an RSA modulus. Applying the special structure of the RSA modulus, an algorithm is presented to overcome the two shortcomings. The new algorithm improves Shor’s algorithm for factoring RSA modulus. The cost of the factorization algorithm almost depends on the calculation of the order of 2 in the multiplication group. 展开更多
关键词 Shor＇s quantum algorithm RSA modulus order
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Blind Equalization Algorithm Based on MCMA and DSE-CMA 认领 引用 被引量：2
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作者 GENG Nian XUE Ni RU Guobao 《Wuhan University Journal of Natural Sciences》 CAS 2008年第1期67-70,共4页
A new blind equalization algorithm based on the modified constant modulus algorithm （MCMA） and dithered signederror constant modulus algorithm （DSE-CMA） is proposed. This dithered signed-error MCMA （DSE-MCMA） ca... A new blind equalization algorithm based on the modified constant modulus algorithm （MCMA） and dithered signederror constant modulus algorithm （DSE-CMA） is proposed. This dithered signed-error MCMA （DSE-MCMA） can not only reduce the computational complexity, but also recover the phase rotation in the complex channel. Simulation results have verified the analysis and indicated the good property of DSE-MCMA. 展开更多
关键词 blind equalization modified constant modulus algorithm （MCMA）, intersymbol interference
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基于L-BFGS的认知雷达区域叠加模糊函数抑制波形设计 认领 引用
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作者 周畅 陈阿磊 +1 位作者 夏云丽 陈文瑾 《空天预警研究学报》 CSCD 2026年第3期157-161,177,共5页
针对邻域强干扰导致认知雷达目标检测性能下降的问题,提出一种区域叠加模糊函数抑制的恒模波形设计方法.首先,将检测中心及其邻域定义为保护区域,建立多个强干扰源经模糊函数旁瓣向保护区域叠加泄漏的模型;然后,采用高阶范数构造区域泄... 针对邻域强干扰导致认知雷达目标检测性能下降的问题,提出一种区域叠加模糊函数抑制的恒模波形设计方法.首先,将检测中心及其邻域定义为保护区域,建立多个强干扰源经模糊函数旁瓣向保护区域叠加泄漏的模型;然后,采用高阶范数构造区域泄漏抑制准则,并利用相位域有限内存Broyden-Fletcher-Goldfarb-Shanno(L-BFGS)算法求解恒模波形.仿真结果表明,本文方法可降低保护区域平均泄漏水平,提高输出信干噪比,在目标位置存在估计偏差或距离-多普勒栅格失配时具有较好的邻域抗干扰能力. 展开更多
关键词 认知雷达 恒模波形设计 区域叠加模糊函数抑制 相位域L-BFGS算法
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基于FPGA的256QAM信号盲均衡算法研究与实现 认领 引用
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作者 赵祎飞 刘世刚 +2 位作者 汪洋 詹海鹏 魏苗苗 《电子产品可靠性与环境试验》 2026年第2期73-79,共7页
针对256QAM信号的盲均衡问题,本文设计并实现了一种基于FPGA的盲均衡器。利用256QAM信号星座图的特征,提出了一种适用于该信号的盲均衡算法,并对星座图进行了详细的区域划分。仿真结果表明,该算法相较于传统恒模算法具有更好的稳态性能... 针对256QAM信号的盲均衡问题,本文设计并实现了一种基于FPGA的盲均衡器。利用256QAM信号星座图的特征,提出了一种适用于该信号的盲均衡算法,并对星座图进行了详细的区域划分。仿真结果表明,该算法相较于传统恒模算法具有更好的稳态性能。在MATLAB平台上进行定点化仿真,验证了算法的易实现性。在Vivado平台上采用Verilog语言完成了FPGA设计,并结合Modelsim软件进行了仿真验证。最后,使用赛灵思(Xilinx)公司的XC7V690TFFG1157-2芯片进行板载测试,结果表明该均衡器能够较好地实现256QAM信号的均衡。 展开更多
关键词 正交振幅调制 盲均衡器 现场可编程逻辑门阵列 恒模算法 盲均衡算法 信号星座图
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基于局部区域效应的注塑齿轮精度评定研究 认领 引用
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作者 王健 周琳琳 《机电工程》 CAS 北大核心 2026年第6期1104-1112,1212,共9页
传统齿轮检测方法效率低下,尤其是针对大批量小模数齿轮难以进行快速自动化测量。为此,开发了一种基于局部区域效应的高精度视觉测量算法,即注塑齿轮精度评定方法。首先,采用数字投影技术完成了齿轮图像采集,并结合局部区域效应方法,完... 传统齿轮检测方法效率低下,尤其是针对大批量小模数齿轮难以进行快速自动化测量。为此,开发了一种基于局部区域效应的高精度视觉测量算法,即注塑齿轮精度评定方法。首先,采用数字投影技术完成了齿轮图像采集,并结合局部区域效应方法,完成了齿轮边缘特征点的亚像素级精确定位,显著提升了边缘检测精度与鲁棒性;将经优化的边缘数据用于确定齿轮几何中心,该中心被确立为所有后续系统测量的精确基准,基于这一稳定参考系,对齿顶圆直径、齿根圆直径、模数及齿数等基本齿轮参数进行了系统测量与分析,在获得基本参数后,逐步完成了关键齿轮精度指标的精密测量;然后,严格遵循齿轮啮合基本原理,对齿廓偏差与齿距偏差进行了精确量化与评估,并依据相关行业标准评定了齿轮的合规等级与质量一致性;最后,在受控条件下构建了预设理想尺寸的参数化合成齿轮模型,对该测量算法的准确性与可靠性进行了验证。研究结果表明:该系统的像素当量为4.769 5μm/pixel,齿廓测量误差始终控制在0.03μm以内;在对模数1 mm、齿数12的齿轮进行的重复性测试中,连续六次测量最大偏差的结果仅为1.7μm,证实了该系统优异的测量一致性与重复性;单齿轮完整测量周期仅需0.46 s,可完成高通量检测。该方法显著提升了小模数齿轮的测量效率与精度,可用于自动化生产线中的在线检测。 展开更多
关键词 小模数齿轮 小模数齿轮视觉检测系统 高精度机器视觉测量算法 局部区域效应 精度评定 亚像素边缘定位 齿轮基本参数
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