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Parameter optimization of controllable local degree of freedom for reducing vibration of flexible manipulator

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Chinese Journal of Aeronautics 2013年第2期26卷 487-494页

作者： Bian Yushu gao zhihui School of Mechanical Engineering and Automation Beihang University State Key Laboratory for Robotics and System (HIT) Harbin Institute of Technology

Parameter optimization of the controllable local degree of freedom is studied for reducing vibration of the flexible manipulator at the lowest possible cost. The controllable local degrees of freedom are suggested and introduced to the topological structure of the flexible manipulator, and used as an effective way to alleviate vibration through dynamic coupling. Parameters introduced by the controllable local degrees of freedom are analyzed and their influences on vibration reduction are investigated. A strategy to optimize these parameters is put forward and the corresponding optimization method is suggested based on Particle Swarm Optimization （PSO）. Simulations are conducted and results of case studies confirm that the proposed optimization method is effective in reducing vibration of the flexible manipulator at the lowest possible cost.

关键词： Degrees of freedom Flexible manipulators Optimization Particle Swarm Optimization Vibration control

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数据流上的约束跨层级高效用项集挖掘

计算机工程与应用 2024年第13期60卷 287-300页

作者：刘淑娟韩萌高智慧穆栋梁李昂北方民族大学计算机科学与工程学院银川750021

传统的高效用项集挖掘算法无法发现不同抽象层级类别之间的关系。因此,有研究者提出了跨层级的高效用项集挖掘算法。针对当前跨层级的高效用项集挖掘算法仅能处理静态数据并且无法控制挖掘层级范围的问题,提出了一种动态类别列表结构DTU... 详细信息

传统的高效用项集挖掘算法无法发现不同抽象层级类别之间的关系。因此,有研究者提出了跨层级的高效用项集挖掘算法。针对当前跨层级的高效用项集挖掘算法仅能处理静态数据并且无法控制挖掘层级范围的问题,提出了一种动态类别列表结构DTUL存储并维护窗口内的项集效用和类别信息。基于此结构,首次提出了基于滑动窗口的约束跨层级高效用项集挖掘算法,包括自下而上挖掘的CCLHM_DTU算法和自上而下挖掘的CCLHM_UTD算法。在含有类别信息的数据集上进行了大量实验,实验结果表明提出的算法能够有效处理数据流并灵活约束项集的层级范围。

关键词：高效用项集挖掘跨层级高效用项集数据流滑动窗口效用列表

Impact vibration reduction for flexible manipulators via controllable local degrees of freedom

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Chinese Journal of Aeronautics 2013年第5期26卷 1303-1309页

作者： Bian Yushu gao zhihui Deng Yuchun School of Mechanical Engineering and Automation Beihang University

When performing operation tasks, the interaction between a flexible manipulator and a grasped object usually results in an impact. In this paper, a new way is suggested to alleviate impact vibration of a flexible manipulator via its structural characteristic when capturing a moving object. Controllable local degrees of freedom are introduced to the topological structure of the flexible manipulator, and used as an effective tool to combat impact vibration through dynamic coupling. A corresponding method is put forward to reduce impact vibration responses of the flexible manip- ulator via the controllable local degrees of freedom. By planning motion of the controllable local degrees of freedom, appropriate control force can be constructed to increase the modal damping and stiffness and eliminate the exciting force simultaneously, thereby reducing impact vibration responses of the flexible manipulator. Simulations are conducted and results are shown to prove the presented method.

关键词： Degrees of freedom Dynamics Flexible manipulators Impact Vibration control

CO_(2)工质空调系统应用于环保型电力机车研究

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铁道机车与动车 2024年第5期 12-14页

作者：梁东高智慧中车大同电力机车有限公司山西大同037038

在节能环保和可持续发展的新形势下,对环保型机车上应用的CO_(2)工质空调系统、机车司机室热工计算、司机室舒适度分析、空调选型进行说明,最终验证设计方案的可行性。

关键词：氢燃料机车 CO_(2)冷媒空调热工计算空调机组选型司机室舒适度分析及验证

OPTIMAL CONTROL OF THE FLEXI-BLE LINK MANIPULATOR WITH CONTROLLABLE LOCAL DEGREES OF FREEDOM

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Chinese Journal of Mechanical Engineering 2008年第4期21卷 27-30页

作者： BIAN Yushu YUN Chao gao zhihui School of Mechanical Engineering and Automation Beihang Universily Beijing 100083 China State Key Laboratory for Manufacturing Systems Engineering Xi＇an Jiaotong University Xi＇an 710049 China School of Mechanical Engineering and Automation Beihang University Beijing 100083 China

Although flexible manipulators own many potential advantages, one of their major disadvantages is the deterioration of the end-effector accuracy due to the flexibility. Therefore, how to reduce vibration is a significant problem. Inspired by the observation on the motion behaviors of animals, a new idea of decreasing motion deflection of the flexible manipulator is suggested. The concept of controllable local degrees of freedom is proposed and analyzed. By way of optimizing local motion provided by the controllable local degrees of freedom, the end-effector deflection of the flexible manipulator can be effectively decreased through dynamic coupling. The corresponding optimal method for vibration control of the flexible manipulator is put forward. The kinematic simulation is carried ant on a three-link flexible manipulator The corresponding results verify the feasibility of this method.

关键词： Flexible manipulator Vibration Flexibility Local degree of freedom

COUPLING EFFECT OF FLEXIBLE JOINT AND FLEXIBLE LINK ON DYNAMIC SINGULARITY OF FLEXIBLE MANIPULATOR

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Chinese Journal of Mechanical Engineering 2008年第1期21卷 9-12页

作者： gao zhihui YUN Chao BIAN Yushu School of Mechanical Engineering and Automation Beihang University Beijing 100083 China

The coupling effect of the flexible joint and the flexible link on the dynamic singularity of the flexible manipulator is addressed. Firstly, the dynamic equations of a flexible manipulator with a flexible joint and a flexible link are derived. Secondly, the relationship and property between the flexible joint and the flexible link are analyzed. It shows that the flexible joint＇s amplitude will increase abruptly, thereby the dynamic singularity occurs if the frequency of a flexible joint is near or equal to some natural frequency of a flexible link. Finally, some numerical simulations which will verify the correctness of the theoretical analysis, are carded out. The results are fundamental for the design of a flexible manipulator and for the avoidance of the dynamic singularity.

关键词： Dynamic singularity Resonance Natural frequency Flexible manipulator

Designing and Optimization of an Off-line Programming System for Robotic Belt Grinding Process

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Chinese Journal of Mechanical Engineering 2011年第4期24卷 647-655页

作者： WANG Wei YUN Chao ZHANG Ling gao zhihui Robotics Institute Beihang University Beijing 100191 China State Key Laboratory for Manufacturing Systems Engineering Xi＇an Jiaotong University Xi＇an 710049 China

Off-line programming （OLP） system becomes one of the most important programming modules for the robotic belt grinding process, however there lacks research on increasing the grinding dexterous space depending on the OLP system. A new type of grinding robot and a novel robotic belt grinding workcell are forwarded, and their features are briefly introduced. An open and object-oriented off-line programming system is developed for this robotic belt grinding system. The parameters of the trimmed surface are read from the initial graphics exchange specification （IGES） file of the CAD model of the workpiece. The deBoor-Cox basis function is used to sample the grinding target with local contact frame on the workpiece. The numerical formula of inverse kinematics is set up based on Newton＇s iterative procedure, to calculate the grinding robot configurations corresponding to the grinding targets. After the grinding path is obtained, the OLP system turns to be more effective than the teach-by-showing system. In order to improve the grinding workspace, an optimization algorithm for dynamic tool frame is proposed and performed on the special robotic belt grinding system. The initial tool frame and the interval of neighboring tool frames are defined as the preparation of the algorithm. An optimized tool local frame can be selected to grind the complex surface for a maximum dexterity index of the robot. Under the optimization algorithm, a simulation of grinding a vane is included and comparison of grinding workspace is done before and after the tool frame optimization. By the algorithm, the grinding workspace can be enlarged. Moreover the dynamic tool frame can be considered to add one degree-of-freedom to the grinding kinematical chain, which provides the theoretical support for the improvement of robotic dexterity for the complex surface grinding.

关键词： off-line programming robotic belt grinding path generation tool optimization

HHUIM:一种新的启发式高效用项集挖掘方法

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计算机应用研究 2024年第1期41卷 94-101页

作者：高智慧韩萌李昂刘淑娟穆栋梁北方民族大学计算机科学与工程学院银川750021

针对基于启发式的高效用项集挖掘算法在挖掘过程中可能丢失大量项集的问题,提出一种新的启发式高效用项集挖掘算法HHUIM。HHUIM利用哈里斯鹰优化算法进行种群更新,能够有效减少项集丢失。提出并设计了鹰的替换策略,解决了搜索空间较大... 详细信息

针对基于启发式的高效用项集挖掘算法在挖掘过程中可能丢失大量项集的问题,提出一种新的启发式高效用项集挖掘算法HHUIM。HHUIM利用哈里斯鹰优化算法进行种群更新,能够有效减少项集丢失。提出并设计了鹰的替换策略,解决了搜索空间较大的问题,降低了适应度函数值低于最小效用阈值的鹰的数量。此外,提出存储回溯策略,可有效防止算法因收敛过快陷入局部最优。大量的实验表明,所提算法优于目前最先进的启发式高效用项集挖掘算法。

关键词：哈里斯鹰优化算法高效用项集挖掘启发式算法智能优化算法

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衍生高效用模式挖掘算法综述

燕山大学学报 2024年第2期48卷 138-156页

作者：刘淑娟韩萌高智慧穆栋梁李昂北方民族大学计算机科学与工程学院宁夏银川750021

在数据挖掘领域中,高效用模式挖掘任务具有较高的理论研究价值和广泛的实际应用场景。针对多变的应用场合,提出了一系列衍生高效用模式。首先从关键技术的角度对高平均效用模式挖掘算法进行了分类论述,主要包括基于先验、基于树、基于... 详细信息

在数据挖掘领域中,高效用模式挖掘任务具有较高的理论研究价值和广泛的实际应用场景。针对多变的应用场合,提出了一系列衍生高效用模式。首先从关键技术的角度对高平均效用模式挖掘算法进行了分类论述,主要包括基于先验、基于树、基于列表、基于投影和基于数据格式的方法。其次,分析讨论了基于全集、精简集以及融合模式的含有负效用的高效用模式挖掘算法。再次,从模糊高效用模式、相关高效用模式和其他新兴高效用模式三个方面概述和总结了扩展高效用模式算法。最后,针对现阶段研究方向的不足,给出下一步的研究方向。

关键词：衍生高效用模式高平均效用模式负效用模糊高效用模式相关高效用模式综述

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