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Analysis and Comparison of Two Jumping Leg Models for Bioinspired Locust Robot

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Journal of Bionic Engineering 2016年第4期13卷 558-571页

作者： Ziqiang Zhang Diansheng chen kewei chen Hanlong chen School of Mechanical Engineering and Automation Beihang University Beijing 100191 China

Bionic jumping robot can cross the obstacles by jumping, and it has a good application prospect in the unstructured com- plex environment. The less Degree of Freedom （DOF） jumping leg, which has the characteristics of simple control and high rigidity, and is very important in research. Based on the experimental observation of leg physiological structure and take-off process of locust, two 1 DOF jumping leg models, which includes four-bar jumping leg model and slider-crank jumping leg model, are established, and multi objective optimization is conducted to deduce the motion law of two 1 DOF jumping leg models and jumping leg of locust is closer. Then the jumping performance evaluation indices are proposed, which include the mechanical property, body attitude, jumping distance and jumping performances of the two jumping leg models environmental effect. According to these evaluation indices, the are analyzed and compared, and the simulation is conducted for further explanations. The analysis results show that the four-bar jumping leg has smaller structural size and its motion law is closer to the hindleg of locust. The slider-crank jumping leg has better mechanical property, stronger energy storage capacity and the rough ground has less effect on it. This study offers a quantitative analysis and comparison for different jumping leg models of bionic locust jumping robot. Furthermore, a theoretical basis for future research and engineering application is established.

关键词： bionic locust robot jumping leg model parameter optimization jumping performance comparison study

Mechanism of Locust Air Posture Adjustment

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Journal of Bionic Engineering 2015年第3期12卷 418-431页

作者： Diansheng chen kewei chen Ziqiang Zhang Benguang Zhang Robotic Institute in School of Mechanical Engineering and Automation Beihang University Beijing 100191 China

Stimulated locusts often tumble during the jumping process. Locusts can also recover their bodies in the air for flight or landing stability. To increase jumping distance and avoid landing collision of bio-inspired jumping robots, the mechanism of air posture adjustment of locusts is examined in this research. This mechanism can be used to improve the stability of robot. The abdomen swings, wing motions, and the variations in body angle are recorded by a high-speed camera when locusts free fall in air with normal or upside-down initial posture. Results indicate that the wings and abdomen are mainly utilized for air posture adjustment. Moreover, abdomen swing and forewing rotation have positive effects on body pitch. However, locusts have dif- ficulty in recovering their bodies from the upside-down posture without wings, although the body pitch caused by unpredictable perturbation in air can be compensated through abdomen swing. Consequently, body roll is attributed to the wing motion, which is related to two factors, namely, the different flapping amplitudes of the wings on both sides, and the different flapping velocities of wings during the upstroke and downstroke periods. This research may provide reference for the design of jumping robots.

关键词： locusts air posture adjustment abdomen swing asymmetric flapping wings

Granular analyzing of weapon SoS demand description

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Journal of Systems Engineering and Electronics 2009年第3期20卷 565-570页

作者： Zhao Qingsong Yang kewei chen Yingwu Li Mengjun School of Information System and Management National Univ. of Defense Technology Changsha 410073 P. R. China

The systematism of weapon combat is the typical characteristic of a modern battlefield. The process of combat is complex and the demand description of weapon system of systems （SOS） is difficult. Granular analyzing is an important method for solving the complex problem in the world. Granular thinking is introduced into the demand description of weapon SoS. Granular computing and granular combination based on a relation of compatibility is proposed. Based on the level of degree and degree of detail, the granular resolution of weapon SoS is defined and an example is illustrated at the end.

关键词： weapon SoS demand description granular analyzing granular resolution.

Prototype Design and Experimental Study on Locust Air-Posture Righting

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Journal of Bionic Engineering 2014年第3期11卷 459-468页

作者： Diansheng chen Junmao Yin kewei chen Kai Zhao Benguang Zhang Robotics Institute Beihang University Beijing 100191 P. R. China

Locust has the capacity to maintain a righting posture and glide through attitude adjustment after leaping. A prototype inspired by the dynamic mechanism of attitude adjustment of locusts was developed. The prototype consists of a pair of wings driven by a four-bar mechanism, and a 2 Degree of Freedom （DOF） tail to imitate the movement of the locust abdomen. The power source, microcontroller, wireless data transmission module, and attitude sensors are contained in the fuselage. Experiments imitating the flight of locust were conducted to determine the mechanism of locust Subsequent Attitude Adjustment （SAA）. The tethered prototype was driven by the movement of the tail and the flapping of the wings. Results show that the pitch and yaw of the tail, and the asymmetric action of the flapping wings significantly influence the posture of the prototype. These findings suggest that both the wiggling abdomen and flapping wings contribute to the locust SAA in the air. This research lays the groundwork and technical support for the probable design and development of practical jumping robots with attitude adjustment function.

关键词： attitude adjustment locust air-posture righting prototype design wiggling tail flapping wing

Analysis of the Influence of Geometrical Parameters on the Performance of a Proton Exchange Membrane Fuel Cell

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Fluid Dynamics & Materials Processing 2024年第1期20卷 219-237页

作者： Guodong Zhang Huifang Tao Da Li kewei chen Guoxiang Li Shuzhan Bai Ke Sun School of Energy and Power Engineering Shandong UniversityJinan250061China Sinotruk Jinan Special Purpose Vehicle Co. Ltd.Jinan250117China

A suitable channel structure can lead to efficient gas distribution and significantly improve the power density of fuel *** this study,the influence of two channel design parameters is investigated,namely,the ratio of the channel width to the bipolar plate ridge width(i.e.,the channel ridge ratio)and the channel *** impact of these parameters is evaluated with respect to the flow pattern,the gas composition distribution,the temperature field and the fuel cell output *** results show that a decrease in the channel ridge ratio and an increase in the channel depth can effectively make the distributions of velocity,temperature and concentration more uniform in each channel and improve the output capability of the fuel *** increase in the channel ridge ratio and depth obviously reduces the flow resistance and improves the flow characteristics.

关键词： Hydrogen fuel cell bipolar plate flow channel multiphysics coupling

Kindergarten Brings up Healthy Children

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Women of China 1995年第5期 46-47页

作者： FENG kewei chen SHANSHAN

THE Dongjiao Kindergarten, a boarding school attached to the Ministry of Foreign Affairs, was established in 1950 under the care of former Premier Zhou Enlai. At that time young mothers usually went to work abroad after their 56-day maternity leave, leaving their children in kindergarten. So from its inception the kindergarten aimed at combining nursing school

关键词： Kindergarten Brings up Healthy Children

Doctor Strives to Prevent and Treat AIDS

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Women of China 1994年第12期 48-49页

作者： FENG kewei chen SHANSHAN

ONE day in 1989, Dr. Xu Lianzhi received laboratory test result from a man over 50, which clearly showed that he had the AIDS virus. This man was Dr. Xu’s first patient who was infected with the AIDS virus, and was also the first case of AIDS discovered during a routine health check in China. Dr. Xu is the head physician of the Department of Infectious Diseases at the Beijing You An Hospital, a member of the Beijing

关键词： Doctor Strives to Prevent and Treat AIDS

ResNet-based Image Classification of Railway Shelling Defect

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ResNet-based Image Classification of Railway Shelling Defect

Successful or pathological cognitive aging?Converging into a“frontal preservation,temporal impairment(FPTI)”hypothesis

第三十九届中国控制会议

作者： Xingguo Song kewei chen Zhongqing Cao Mechanical Engineering school Southwest Jiaotong University Sichuan Provincial Key Laboratory of rail transit operation and maintenance technology and equipment

This paper highlights the ability of residual convolutional neural network（ResNet） at classifying railway shelling defect dataset without the requirement for handcrafted features. A 41-convolutional layers Res Net with the residual learning block is introduced. Bottleneck architecture of three convolutional layers is used in Res Net to decrease the computation *** convolutional neural network（VGGNet） classifier and Support Vector Machine（SVM） classifiers based on Histogram of Oriented Gradient（HOG）, Local Binary Patterns（LBP） and Scale-invariant Feature Transform（SIFT） are compared with Res Net classifier at classifying our dataset. The performance of Res Net presented in this paper achieves 95% TOP-1 accuracy in testing dataset. In comparison, the result of Res Net is better than VGGNet with 92% TOP-1 accuracy and HOG（42.88%）, LBP（52.26%）, SIFT（60.69%）. In the context of designing neural computing models for Res Net analysis, this paper shows that Res Net used in our experiment is able to not only achieve the high accuracy in railway shelling defect testing dataset, but also has a faster testing speed than the other classifiers.

关键词： Deep learning Convolutional neural network Railway shelling defect Image classification

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Science Bulletin 2022年第22期67卷 2285-2290页

作者： Yiru Yang Yaojing chen Feng Sang Shaokun Zhao Jun Wang Xin Li Chuansheng chen kewei chen Zhanjun Zhang State Key Laboratory of Cognitive Neuroscience and Learning Beijing Normal UniversityBeijing 100875China School of Nursing and Rehabilitation Cheeloo College of MedicineShandong UniversityJinan 250012China Beijing Aging Brain Rejuvenation Initiative(BABRI)Center Beijing Normal UniversityBeijing 100875China Department of Psychology and Social Behavior University of CaliforniaIrvine 92697USA Banner Alzheimer’s Institute Phoenix 85006USA

Most elderly individuals experience cognitive decline with increasing age[1],some even suffer from pathological cognitive aging,such as dementia;however,there are exceptional elderly individuals who maintain superior cognitive performance,and they are referred to as those who have experienced successful cognitive aging(SCA)[2].The majority of research has been on pathological cognitive aging and its neural mechanisms,and much less is known about SCA[3].How is SCA characterized neuroanatomically?Specifically,whether SCA individuals’better cognitive maintenance is related to lessening pathological damage to the brain or to the higher preservation of specific brain characteristics that are not related to pathology?The neural mechanisms causing this wide array of individual cognitive differences in aging are largely unknown.

关键词：认知老化灰质体积颞叶损伤脑结构基底神经节额中回特异性损伤认知障碍