Tongzhou District, China
Tongzhou District, China

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Hao Q.,Institute of Army Aviation | Li S.,Institute of Army Aviation | Liu B.,Institute of Army Aviation
Proceedings of 2016 IEEE Advanced Information Management, Communicates, Electronic and Automation Control Conference, IMCEC 2016 | Year: 2016

The kinematic performance optimization of a 2-PRR parallel robot based on new variance indices is given in this paper. First, the inverse kinematic equation of the 2-PRR parallel robot is derived. Then the velocity performance evaluable indices LCI and GCI, the stiffness performance evaluable indices LSI and GSI are analyzed. To consider the distribution of the LCI and LSI in the global indices, two new global kinematic performance indices GCVI and GSVI, which are based on variance calculation, are given. Furthermore, the kinematic performance optimization based on the four global indices is derived. From the simulation result, it can be found that the optimization method based on multi indices can improve the kinematic performance of the parallel robot well. © 2016 IEEE.

Wang L.,Beihang University | Wang L.,Institute of Army Aviation | Yang C.,Beihang University | Yao Z.,Institute of Army Aviation | Jilei Y.,China Electronics Technology Group Corporation
International Conference on Signal Processing Proceedings, ICSP | Year: 2017

In this paper, based on the analysis of the complicated electromagnetic environment in very low altitude area, we propose a helicopter spectrum sensing scheme by integrating the energy detection and the cyclostationary feature detection methods. The proposed scheme is able to satisfy the real-time and high accuracy requirements imposed by implementing spectrum sensing with helicopters. Simulations and experiments with collected data in high frequency band verify that the proposed helicopter spectrum sensing scheme is with good performance is feasible for practice use. Moreover, the proposed scheme can choose suitable communication frequencies for helicopters and enhance the communication assurance capability in low altitude area. © 2016 IEEE.

Huang L.,Institute of Army Aviation | Yang Y.-H.,Institute of Army Aviation | Li H.,China Software Testing Center
Jisuanji Xuebao/Chinese Journal of Computers | Year: 2012

Combinatorial testing is an important part of software test data generation research domain. The parameter pairwise testing is the most widely-used technique. Various parameter pairwise coverage methods for test data generation are surveyed in the paper. The main problem of the existing and dominating pairwise coverage algorithm AETG and IPO is their blindness and randomicity when deciding level value, therefore the size of test cases is difficult to control. Based upon this, improved AETG and IPO algorithms are proposed. In the proposed methods, the size of test cases is effectively controlled by the pretreatment of parameters and the consideration of the level combination of all factors. The level value is decided as early as possible by more consummate way. To validate the effectiveness of new algorithms, emulation experiments and practical testing are carried out. The experiment results show that the number of test cases generated by improved algorithms is smaller than the one by original algorithms, and the reduction effect is more evident; disciplinarian relation exists between test case amount and pairwise amount, also between test case amount and factor level amount. A series of conclusions are drawn by analyzing the results. On the basis of pairwise coverage, n-way combinatorial coverage algorithm which combined with genetic and AETG algorithm is proposed. The fact that time complexity of new algorithm is lower than existing method is also proved.

Huang L.,Jilin University | Qi J.,Institute of Army Aviation | Tan Y.,Jilin University | Yang B.,Jilin University
Tien Tzu Hsueh Pao/Acta Electronica Sinica | Year: 2012

For the optimization problem of rectangular packing in manufacturing field, a genetic-discrete particle swarm optimization is proposed. Through introducing the concepts of exchange operator and exchange sequence, the difficult problem of describing the update particles in the standard particle swarm optimization algorithm for combinatorial optimization problem is solved. Combining the idea of mutation and crossover in genetic algorithm strengthens the diversity and stability of the particle swarm. An improved lowest horizontal search algorithm is proposed to accelerate the convergence speed and can be used to decode to packing layout. The experimental data show that the proposed algorithm is effective and robust in solving the problem of rectangular packing.

Hao Q.,Tsinghua University | Hao Q.,Institute of Army Aviation | Guan L.,Tsinghua University | Wang J.,Tsinghua University | Wang L.,Tsinghua University
Chinese Journal of Mechanical Engineering (English Edition) | Year: 2011

Parallel manipulators with less than six degrees of freedom (DOF) have been increasingly used in high-speed hybrid machine tools. The structural features of parallel manipulators are dynamic, a characteristic that is particularly significant when these manipulators are used in high-speed machine tools. However, normal kinematic control method cannot satisfy the requirements of the control system. Many researchers use model-based dynamic control methods, such as the dynamic feedforward control method. However, these methods are rarely used in hybrid machine tools because of the complex dynamic model of the parallel manipulator. In order to study the dynamic control method of parallel manipulators, the dynamic feedforward control method is used in the dynamic control system of a 3-PSP (prismatic-spherical-prismatic) 3-DOF spatial parallel manipulator used as a spindle head in a high-speed hybrid machine tool. Using kinematic analysis as basis and the Newton-Euler method, we derive the dynamic model of the parallel manipulator. Furthermore, a model-based dynamic feedforward control system consisting of both kinematic control and dynamic control subsystems is established. The dynamic control subsystem consists of two modules. One is used to eliminate the influence of the dynamic characteristics of high-speed movement, and the other is used to eliminate the dynamic disturbances in the milling process. Finally, the simulation model of the dynamic feedforward control system of the 3-PSP parallel manipulator is constructed in Matlab/Simulink. The simulations of the control system eliminating the influence of the dynamic characteristics and dynamic disturbances are conducted. A comparative study between the simulations and the normal kinematic control method is also presented. The simulations prove that the dynamic feedforward control method effectively eliminates the influence of the dynamic disturbances and dynamic characteristics of the parallel manipulator on high-speed machine tools, and significantly improves the trajectory accuracy. This is the first attempt to introduce the dynamic feedfordward control method into the 3-PSP spatial parallel manipulator whose dynamic model is complex and provides a study basis for the real-time dynamic control of the high-speed hybrid machine tools. ©2011 Chinese Journal of Mechanical Engineering.

Hao Q.,Institute of Army Aviation | Liu B.,Institute of Army Aviation | Wang M.,Institute of Army Aviation | Zhou J.,Beijing Aerospace Measurement and Control Technology Co.
2016 IEEE International Conference on Mechatronics and Automation, IEEE ICMA 2016 | Year: 2016

In order to optimize the kinematic and dynamic performance of a 2-DoF planar parallel mechanism used in hybrid machines, a multi-objective optimization method is introduced. Based on the compare of the common kinematic analysis method and dynamic analysis method, the kinematic and dynamic performances evaluation indices which can be used in the performance optimization are introduced. Then a multi indices optimization method based on genetic algorithm is investigated to achieve the multi performance optimization of the parallel mechanism. In the optimization method, the kinematic, stiffness and dynamic performances are improved by optimizing the geometric and structural parameters of the parallel mechanism. The simulation result indicates that the optimization method is of practical value to improve the development of the parallel mechanism. © 2016 IEEE.

Hao Q.,Institute of Army Aviation | Hao Q.,Tsinghua University | Guan L.,Tsinghua University | Wang J.,Tsinghua University | Wang L.,Tsinghua University
2010 IEEE Conference on Robotics, Automation and Mechatronics, RAM 2010 | Year: 2010

Dynamic manipulability is a very important issue that should be considered for problems of parallel manipulator design. In order to study the dynamic optimization of a 2-DOF planar parallel manipulator, which is used in a heavy duty hybrid machine, genetic algorithm (GA) is used in the dynamic manipulability optimization. Based on the kinematic analysis, the dynamic equation of the 2-DOF parallel manipulator is derived using the virtual work principle method. Furthermore, global dynamic manipulability (GDM) is introduced to measure the dynamic performance of the manipulator. Then the dynamic optimization based GA method is analyzed. From the numerical simulation, it is proved that the dynamic optimization considering GDM proposed in this paper can ameliorate the dynamic performance of the parallel manipulator well. ©2010 IEEE.

Liu B.-B.,Tsinghua University | Liu B.-B.,Institute of Army Aviation | Tian L.,Tsinghua University | Yang Y.-H.,Institute of Army Aviation
Jisuanji Jicheng Zhizao Xitong/Computer Integrated Manufacturing Systems, CIMS | Year: 2012

Special requirements of aviation virtual maintenance could not be satisfied with existing domestic virtual maintenance systems. To solve this problem, a framework of aviation virtual maintenance system was presented. System key technologies such as localization of human model, extensible maintenance resource management oriented to level of repair, maintenance process management oriented to maintenance quality design, repair time estimation and comprehensive maintainability evaluation were studied emphatically. The system was developed based on DELMIA software. Taking fuel dumping of a helicopter as an example, all functions of the system were verified.

Hao Q.,Tsinghua University | Hao Q.,Institute of Army Aviation | Guan L.,Tsinghua University | Wang L.,Tsinghua University
Qinghua Daxue Xuebao/Journal of Tsinghua University | Year: 2010

The control parameter tuning of motor servo systems in parallel machine tools is the basis of the analysis of dynamic control systems in parallel machine tools. Genetic algorithm (GA) was used to optimize the control parameters of the speed control loop and position control loop of the motor servo system separately, after the authors of this paper previously presented the optimized index of PID parameters based on the time-domain performance and dynamic characteristics. The optimized results were compared with those optimized using the traditional Ziegler-Nichols tuning laws. Genetic algorithm was then used to optimize all control parameters of several control loops at the same time with desired results which were used in the kinematics control systems of the parallel machine tools for computer simulation. Simulation results show that the optimization process for optimizing the parameters of several motor servo system control loops based on GA has significant advantages such as simple calculation, higher optimization speeds and satisfactory results.

Zhang H.,Beijing University of Posts and Telecommunications | Zhang H.,2China Electronic Equipment System Engineering Corporation | Qiu X.-S.,Beijing University of Posts and Telecommunications | Meng L.-M.,Beijing University of Posts and Telecommunications | And 2 more authors.
2010 IEEE Globecom Workshops, GC'10 | Year: 2010

Future Long Term Evolution (LTE) Radio Access Network (RAN) 1 will benefit from a significant degree of self-organization. Autonomic Load Balancing (ALB) is considered as an important self-organizing function in LTE RAN. In this work, distributed ALB is achieved by Autonomic Network Management (ANM). Load conditions of eNBs (E-UTRAN NodeB) can be detected. Sizes and shapes of cellular coverage can be adjusted automatically according to load conditions, so as to balance load. Simulation results demonstrated that by the use of ALB, the system capacity can be improved significantly. ©2010 IEEE.

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