In order to overcome the shortcoming of the classical Hungarian algorithm that it can only solve the problems where the total cost is the sum of that of each job, an improved Hungarian algorithm is proposed and used t...In order to overcome the shortcoming of the classical Hungarian algorithm that it can only solve the problems where the total cost is the sum of that of each job, an improved Hungarian algorithm is proposed and used to solve the assignment problem of serial-parallel systems. First of all, by replacing parallel jobs with virtual jobs, the proposed algorithm converts the serial-parallel system into a pure serial system, where the classical Hungarian algorithm can be used to generate a temporal assignment plan via optimization. Afterwards, the assignment plan is validated by checking whether the virtual jobs can be realized by real jobs through local searching. If the assignment plan is not valid, the converted system will be adapted by adjusting the parameters of virtual jobs, and then be optimized again. Through iterative searching, the valid optimal assignment plan can eventually be obtained.To evaluate the proposed algorithm, the valid optimal assignment plan is applied to labor allocation of a manufacturing system which is a typical serial-parallel system.展开更多
The concept of legged-robot stability training with a training platform is proposed and a serial-parallel mechanism platform with 6 degrees of freedom is designed for this target. The designed platform is composed of ...The concept of legged-robot stability training with a training platform is proposed and a serial-parallel mechanism platform with 6 degrees of freedom is designed for this target. The designed platform is composed of 4-DOF parallel mechanism with spherical joints and prismatic pairs,and 2-DOF serial mechanism with prismatic pairs. With this design,the platform has advantages of low platform countertop,big workspace,high carrying capacity and high stiffness. On the basis of DOF analysis and computation of space mechanism,weight supporting auxiliary mechanism and raceways-balls supporting mechanism are designed,so as to improve the stiffness of designed large platform and payload capacity of servo motors. And then the whole structure design work of the platform is done. Meanwhile,this paper derives the analytical solutions of forward kinematics, inverse kinematics and inverse dynamics. The error analysis model of position and orientation is established. And then the simulation is done in ADAMS to ensure the correctness and feasibility of this design.展开更多
3-PRS serial-parallel machine tool consists of a 3-degree-of-freedom (DOF) implementation platform and a 2-DOF X-Y platform. The error modeling and parameter identification methods were deduced based on 3-PRS serial-p...3-PRS serial-parallel machine tool consists of a 3-degree-of-freedom (DOF) implementation platform and a 2-DOF X-Y platform. The error modeling and parameter identification methods were deduced based on 3-PRS serial-parallel machine tool. 3-PRS serial-parallel machine tool was researched, and the mechanism of error analysis, modeling, identification of error parameters and measurement equipment for the use of agency error of measurement were conducted. In order to achieve the geometric parameters calibration and error compensation of the serial-parallel machine tool, the nominal structural parameters of the controller was adjusted by identifying the structure of the machine tool. With the establishment of a vector space size chain, we can do the error analysis, error modeling, error measurement and error compensation can be done.展开更多
A five-axis serial-parallel kinematic milling machine, the SPKM 165, is introduced. This machine consists of a three-degree of-freedom parallel module and a two-degree-of-freedom serial table. The SPKM 165 is capable ...A five-axis serial-parallel kinematic milling machine, the SPKM 165, is introduced. This machine consists of a three-degree of-freedom parallel module and a two-degree-of-freedom serial table. The SPKM 165 is capable of five-face machining. A discussion of the inverse kinematics of the five-axis control is provided. A dimensional synthesis procedure is presented in terms of motion/force transmissibility. Finite-element analysis was used to evaluate the stiffness of a CAD model before the machine was manufactured. Kinematic calibration was implemented to improve the accuracy of the end effector. The results of a calibration experiment are presented. The stiffness of the developed machine was then measured. Milling experiments were conducted, and the test piece showed that the developed machine has satisfactory performance.展开更多
在大规模红外读出电路中,接口电路的数据传输效率及接口数量尤为关键。传统接口电路采用并行接口进行数据传输,这种方式会占用较多的芯片引脚。为了提升数据的传输效率,设计了一款用于数据接收的3通道串行低压差分信号(Low Voltage Diff...在大规模红外读出电路中,接口电路的数据传输效率及接口数量尤为关键。传统接口电路采用并行接口进行数据传输,这种方式会占用较多的芯片引脚。为了提升数据的传输效率,设计了一款用于数据接收的3通道串行低压差分信号(Low Voltage Differential Signaling, LVDS)接口电路。电路采用0.18um互补金属氧化物半导体(Complementary Metal Oxide Semiconductor, CMOS)工艺设计。仿真结果表明,LVDS接口电路在400 MHz频率下,能够将2路接收端数据转换为8路数据并将其输出给内部数字处理单元。与传统并行接口相比,本电路节省了6个数据传输引脚,大大提高了数据传输效率。展开更多
多标签学习已成功应用于文本分类、图像识别等各个领域。流行的技术包括提取标签特定特征、利用标签相关性等。提出带有标签相关性的预测调整算法PALC(Prediction adjusting with label correlation)将标签相关性融入串行并行神经网络...多标签学习已成功应用于文本分类、图像识别等各个领域。流行的技术包括提取标签特定特征、利用标签相关性等。提出带有标签相关性的预测调整算法PALC(Prediction adjusting with label correlation)将标签相关性融入串行并行神经网络。一方面,采用新颖的、更有效的串行并行神经网络架构来替代常见的显式特征提取或压缩感知方法;另一方面,考虑用固有的标签矩阵内的相关性来计算相关性矩阵,并以流形正则的方式优化分类器。对10个基准数据集与7种流行算法进行比较,结果表明PALC在3大排名指标下均有优势。展开更多
文摘In order to overcome the shortcoming of the classical Hungarian algorithm that it can only solve the problems where the total cost is the sum of that of each job, an improved Hungarian algorithm is proposed and used to solve the assignment problem of serial-parallel systems. First of all, by replacing parallel jobs with virtual jobs, the proposed algorithm converts the serial-parallel system into a pure serial system, where the classical Hungarian algorithm can be used to generate a temporal assignment plan via optimization. Afterwards, the assignment plan is validated by checking whether the virtual jobs can be realized by real jobs through local searching. If the assignment plan is not valid, the converted system will be adapted by adjusting the parameters of virtual jobs, and then be optimized again. Through iterative searching, the valid optimal assignment plan can eventually be obtained.To evaluate the proposed algorithm, the valid optimal assignment plan is applied to labor allocation of a manufacturing system which is a typical serial-parallel system.
基金Sponsored by the National High-Tech Research and Development Program(Grant No.2006AA04Z201)
文摘The concept of legged-robot stability training with a training platform is proposed and a serial-parallel mechanism platform with 6 degrees of freedom is designed for this target. The designed platform is composed of 4-DOF parallel mechanism with spherical joints and prismatic pairs,and 2-DOF serial mechanism with prismatic pairs. With this design,the platform has advantages of low platform countertop,big workspace,high carrying capacity and high stiffness. On the basis of DOF analysis and computation of space mechanism,weight supporting auxiliary mechanism and raceways-balls supporting mechanism are designed,so as to improve the stiffness of designed large platform and payload capacity of servo motors. And then the whole structure design work of the platform is done. Meanwhile,this paper derives the analytical solutions of forward kinematics, inverse kinematics and inverse dynamics. The error analysis model of position and orientation is established. And then the simulation is done in ADAMS to ensure the correctness and feasibility of this design.
基金supported by Program for New Century Excellent Talents in University of Henan Province (GrantNo, 2006HANCET-16)program for The Fund of Henan Polytechnic University Postgraduate’s Innovative Papers (Grant No, 644013)program for Young Talents of Henan Polytechnic University (Grant No,649035)
文摘3-PRS serial-parallel machine tool consists of a 3-degree-of-freedom (DOF) implementation platform and a 2-DOF X-Y platform. The error modeling and parameter identification methods were deduced based on 3-PRS serial-parallel machine tool. 3-PRS serial-parallel machine tool was researched, and the mechanism of error analysis, modeling, identification of error parameters and measurement equipment for the use of agency error of measurement were conducted. In order to achieve the geometric parameters calibration and error compensation of the serial-parallel machine tool, the nominal structural parameters of the controller was adjusted by identifying the structure of the machine tool. With the establishment of a vector space size chain, we can do the error analysis, error modeling, error measurement and error compensation can be done.
基金supported in part by the National Natural Science Foundation of China (Grant No. 51075222)the Fund of State Key Laboratory of Tribology (Grant No. SKLT10C02)
文摘A five-axis serial-parallel kinematic milling machine, the SPKM 165, is introduced. This machine consists of a three-degree of-freedom parallel module and a two-degree-of-freedom serial table. The SPKM 165 is capable of five-face machining. A discussion of the inverse kinematics of the five-axis control is provided. A dimensional synthesis procedure is presented in terms of motion/force transmissibility. Finite-element analysis was used to evaluate the stiffness of a CAD model before the machine was manufactured. Kinematic calibration was implemented to improve the accuracy of the end effector. The results of a calibration experiment are presented. The stiffness of the developed machine was then measured. Milling experiments were conducted, and the test piece showed that the developed machine has satisfactory performance.
文摘在大规模红外读出电路中,接口电路的数据传输效率及接口数量尤为关键。传统接口电路采用并行接口进行数据传输,这种方式会占用较多的芯片引脚。为了提升数据的传输效率,设计了一款用于数据接收的3通道串行低压差分信号(Low Voltage Differential Signaling, LVDS)接口电路。电路采用0.18um互补金属氧化物半导体(Complementary Metal Oxide Semiconductor, CMOS)工艺设计。仿真结果表明,LVDS接口电路在400 MHz频率下,能够将2路接收端数据转换为8路数据并将其输出给内部数字处理单元。与传统并行接口相比,本电路节省了6个数据传输引脚,大大提高了数据传输效率。
文摘多标签学习已成功应用于文本分类、图像识别等各个领域。流行的技术包括提取标签特定特征、利用标签相关性等。提出带有标签相关性的预测调整算法PALC(Prediction adjusting with label correlation)将标签相关性融入串行并行神经网络。一方面,采用新颖的、更有效的串行并行神经网络架构来替代常见的显式特征提取或压缩感知方法;另一方面,考虑用固有的标签矩阵内的相关性来计算相关性矩阵,并以流形正则的方式优化分类器。对10个基准数据集与7种流行算法进行比较,结果表明PALC在3大排名指标下均有优势。