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Virtual Simulation System with Path-following Control for Lunar Rovers Moving on Rough Terrain

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Chinese Journal of Mechanical Engineering 2012年第1期25卷 38-46页

作者： GAO Haibo DENG Zongquan ding liang WANG Mengyu State Key Laboratory of Robotics and Systems Harbin Institute of TechnologyHarbin 150001China School of Mechatronics Harbin Institute of TechnologyHarbin 150001China

Virtual simulation technology is of great importance for the teleoperation of lunar rovers during the exploration phase, as well as the design of locomotion systems, performance evaluation, and control strategy verification during the R&D phase. The currently used simulation methods for lunar rovers have several disadvantages such as poor fidelity for wheel-soil interaction mechanics, difficulty in simulating rough terrains, and high complexity making it difficult to realize mobility control in simulation systems. This paper presents an approach for the construction of a virtual simulation system that integrates the features of 3D modeling, wheel-soil interaction mechanics, dynamics analysis, mobility control, and visualization for lunar rovers. Wheel-soil interaction experiments are carried out to test the forces and moments acted on a lunar rover’s wheel by the soil with a vertical load of 80 N and slip ratios of 0, 0.03, 0.05, 0.1, 0.2, 0.3, 0.4, and 0.6. The experimental results are referenced in order to set the parameters’ values for the PAC2002 tire model of the ADAMS/Tire module. In addition, the rough lunar terrain is simulated with 3DS Max software after analyzing its characteristics, and a data-transfer program is developed with Matlab to simulate the 3D reappearance of a lunar environment in ADAMS. The 3D model of a lunar rover is developed by using Pro/E software and is then imported into ADAMS. Finally, a virtual simulation system for lunar rovers is developed. A path-following control strategy based on slip compensation for a six-wheeled lunar rover prototype is researched. The controller is implemented by using Matlab/Simulink to carry out joint simulations with ADAMS. The designed virtual lunar rover could follow the planned path on a rough terrain. This paper can also provide a reference scheme for virtual simulation and performance analysis of rovers moving on rough lunar terrains.

关键词： lunar rover comprehensive simulation system rough terrain wheel-soil interaction mechanics path-following control

Sagittal SLIP-anchored task space control for a monopode robot traversing irregular terrain

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Frontiers of Mechanical Engineering 2020年第2期15卷 193-208页

作者： Haitao YU Haibo GAO liang ding Zongquan DENG State Key Laboratory of Robotics and Systems Harbin Institute of TechnologyHarbin 150001China

As a well-explored template that captures the essential dynamical behaviors of legged locomotion on sagittal plane,the spring-loaded inverted pendulum(SLIP)model has been extensively employed in both biomechanical study and robotics *** at fully leveraging the merits of the SLIP model to generate the adaptive trajectories of the center of mass(CoM)with maneuverability,this study presents a novel two-layered sagittal SLIP-anchored(SSA)task space control for a monopode robot to deal with terrain *** work begins with an analytical investigation of sagittal SLIP dynamics by deriving an approximate solution with satisfactory apex prediction accuracy,and a two-layered SSA task space controller is subsequently developed for the monopode *** higher layer employs an analytical approximate representation of the sagittal SLIP model to form a deadbeat controller,which generates an adaptive reference trajectory for the *** lower layer enforces the monopode robot to reproduce a generated CoM movement by using a task space controller to transfer the reference CoM commands into joint torques of the multi-degree of freedom monopode ***,an adaptive hopping behavior is exhibited by the robot when traversing irregular *** results have demonstrated the effectiveness of the proposed method.

关键词： legged robots spring-loaded inverted pendulum task space control apex return map deadbeat control irregular terrain negotiation

Electric-controlled metasurface antenna array with ultra-wideband frequency reconfigurable reflection suppression

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Journal of Systems Engineering and Electronics 2023年第6期34卷 1473-1482页

作者： ZHENG Yuejun CHEN Qiang ding liang YUAN Fang FU Yunqi College of Electronic Science and Technology National University of Defense TechnologyChangsha 410073China

The electric-controlled metasurface antenna array(ECMSAA)with ultra-wideband frequency reconfigurable reflection suppression is proposed and ***,an electriccontrolled metasurface with ultra-wideband frequency reconfigurable in-phase reflection characteristics is *** element of the ECMSAA is constructed by loading the single electric-controlled metasurface unit on the conventional patch antenna *** radiation properties of the conventional patch antenna and the reflection performance of electric-controlled metasurface are maintained when the antenna and the metasurface are ***,the ECMSAA elements have excellent radiation properties and ultra-wideband frequency reconfigurable in-phase reflection characteristics *** take a further step,a 6×10 ECMSAA is realized based on the designed metasurface antenna *** and measured results prove that the reflection of the ECMSAA is dynamically suppressed in the P and L ***,high-gain and multi-polarization radiation properties of the ECMSAA are *** design method not only realizes the frequency reconfigurable reflection suppression of the antenna array in the ultra-wide frequency band but also provides a way to develop an intelligent low-scattering antenna.

关键词： electric-controlled metasurface antenna array(ECMSAA) radiation reflection frequency reconfigurable.

Chaotic Dynamics of Triatomic Normal Mode Molecules

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Chinese Physics Letters 2012年第6期29卷 118-121页

作者： ZHAI liang-Jun ZHENG Yu-Jun ding Shi-liang School of Physics Shandong UniversityJinan 250100

We investigate the chaotic dynamics of normal mode molecules from the classical point of view using the coupling Morse *** interesting phenomena of the fractured tori and the cross of tori on the poincaré section,which go against our traditional understanding,are found and ***,we find that the phenomenon of tori cross is a siggature of the single bond's energy beyond the total vibrational ***,a method to improve this scarcity is proposed.

关键词： energy vibrational Morse

EXISTENCE OF MULTIPLE PERIODIC SOLUTIONS TO LOTKA-VOLTERRA NETWORK-LIKE FOOD-CHAIN SYSTEM WITH DELAYS AND IMPULSES ON TIME SCALES

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International Journal of Biomathematics 2014年第1期7卷 39-68页

作者： KAIHONG ZHAO liang ding FENGZAO YANG Department of Applied MathematicsKunming University of Science and Technology Yunnan Kunming 650093 P. R. China

In this paper, we have studied a general kind of n-species Lotka-Volterra network- like food-chain system with delays and impulses on time scales. Applying Mawhin＇s continuation theorem of coincidence degree theory and some skills of inequalities, some sufficient criteria have been established to guarantee the existence of at least 2n periodic solutions to this model. One example is given to illustrate the effectiveness of our results.

关键词： Time scales network-like food-chain system coincidence degree multiple periodic solutions time delays and impulses

Method for Analyzing Articulated Torques of Heavy-duty Six-legged Robot

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Chinese Journal of Mechanical Engineering 2013年第4期26卷 801-812页

作者： ZHUANG Hongchao GAO Haibo ding liang LIU Zhen DENG Zongquan State Key Laboratory of Robotics and System Harbin Institute of Technology

The accuracy of an articulated torque analysis influences the comprehensive performances of heavy-duty multi-legged robots. Currently, the extremal estimation method and some complex methods are employed to calculate the articulated torques, which results in a large safety margin or a large number of calculations. To quickly obtain accurate articulated torques, an analysis method for the articulated torque is presented for an electrically driven heavy-duty six-legged robot. First, the rearmost leg that experiences the maximum normal contact force is confirmed when the robot transits a slope. Based on the ant-type and crab-type tripod gaits, the formulas of classical mechanics and MATLAB software are employed to theoretically analyze the relevant static torques of the joints. With the changes in the joint angles for the abductor joint, hip joint, and knee joint, variable tendency charts and extreme curves are obtained for the static articulated torques. Meanwhile, the maximum static articulated torques and the corresponding poses of the robot are also obtained. According to the poses of the robot under the maximum static articulated torques, ADAMS software is used to carry out a static simulation analysis. Based on the relevant simulation curves of the articulated torques, the maximum static articulated torques are acquired. A comparative analysis of the maximum static articulated torques shows that the theoretical calculation values are higher than the static simulation values, and the maximum error value is approximately 10%. The proposed method lays a foundation for quickly determining accurate articulated torques to develop heavy-duty six-legged robots.

关键词： heavy-duty six-legged robot articulated torque MATLAB static simulation analysis ADAMS

The key role of gut-liver axis in pyrrolizidine alkaloid-induced hepatotoxicity and enterotoxicity

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Acta Pharmaceutica Sinica B 2021年第12期11卷 3820-3835页

作者： Yisheng He Jiang Ma Xiaoyu Fan liang ding Xinxin ding Qing-Yu Zhang Ge Lin School of Biomedical Sciences Faculty of Medicinethe Chinese University of Hong KongHong Kong SAR 999077China Department of Pharmacology&Toxicology College of PharmacyUniversity of ArizonaTucsonAZ 85721USA

Pyrrolizidine alkaloids(PAs) are the most common phytotoxins with documented human *** require metabolic activation by cytochromes P450 to generate toxic intermediates which bind to proteins and form protein adducts,thereby causing *** study investigated the role of the gut-liver axis in PA intoxication and the underlying *** exposed mice to retrorsine(RTS),a representative PA,and for the first time found RTS-induced intestinal epithelium damage and disruption to intestinal barrier *** mice with tissue-selective ablation of P450 activity,we found that hepatic P450 s,but not intestinal P450 s,were essential for PA ***,in RTS-exposed,bile duct-cannulated rats,we found the liver-derived reactive PA metabolites were transported by bile into the intestine to exert *** impact of gut-derived pathogenic factors in RTS-induced hepatotoxicity was further studied in mice with dextran sulfate sodium(DSS)-induced chronic *** treatment increased the hepatic endotoxin level and depleted hepatic reduced glutathione,thereby suppressing the PA detoxification *** to RTS-exposed normal mice,the colitic mice displayed more severe RTS-induced hepatic vasculature damage,fibrosis,and ***,our findings provide the first mode-of-action evidence of PA-induced enterotoxicity and highlight the importance of gut barrier function in PA-induced liver injury.

关键词： Pyrrolizidine alkaloid Cytochrome P450 Inflammatory bowel disease Intestinal injury Liver injury Gut-liver axis

Prediction of extreme wind velocity at the site of the Runyang Suspension Bridge

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第8期12卷 605-615页

作者： Yang DENG You-liang ding Ai-qun LI Guang-dong ZHOU Key Laboratory of Concrete and Prestressed Concrete Structures of Ministry of Education Southeast University Nanjing 210096 China

This paper presents a distribution free method for predicting the extreme wind velocity from wind monitoring data at the site of the Runyang Suspension Bridge (RSB), China using the maximum entropy theory. The maximum entropy theory is a rational approach for choosing the most unbiased probability distribution from a small sample, which is consistent with available data and contains a minimum of spurious information. In this paper, the theory is used for estimating a joint probability density function considering the combined action of wind speed and direction based on statistical analysis of wind monitoring data at the site of the RSB. The joint probability distribution model is further used to estimate the extreme wind velocity at the deck level of the RSB. The results of the analysis reveal that the probability density function of the maximum entropy method achieves a result that fits well with the monitoring data. Hypothesis testing shows that the distributions of the wind velocity data collected during the past three years do not obey the Gumbel distribution. Finally, our comparison shows that the wind predictions of the maximum entropy method are higher than that of the Gumbel distribution, but much lower than the design wind speed.

关键词： Extreme wind velocity Maximum entropy theory Probability density function Structural health monitoring(SHM)

Perylene Bisimide In-chain Polyethylene with Unique Self-assembly Nanostructure through Acyclic Diene Metathesis(ADMET)Polymerization

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Chinese Journal of Polymer Science 2018年第6期36卷 703-711页

作者： Wei Song Yang You Tian-Jing Li Juan Li liang ding Department of Polymer and Composite Material School of Materials EngineeringYancheng Institute of TechnologyYancheng 224051China Roy&Diana Vagelos Laboratories Department of ChemistryUniversity of PennsylvaniaPhiladelphia 19104-6323PAUSA School of Automotive Engineering Yaneheng Vocational Institute of Industry TechnologyYancheng 224005China

A novel perylene tetracarboxylic acid bisimide（PTCBI） in-chain polyethylene（PE） was first prepared via acyclic diene metathesis（ADMET） polymerization of PTCBI-functionalized α,ω-diene monomer. The polymers could spontaneously self-assemble into hollow cylindrical structures in which the π-π interaction between adjacent PTCBI moieties was enhanced and the electron mobility was possibly promoted. The hydrogenation of as-obtained polymer was readily accomplished, affording the desired precision PTCBI in-chain PE with a saturated backbone, which showed high glass transition temperature（Tg = 63 °C）, relatively wide range of light absorption（λ = 200-575 nm）, and higher LUMO level（-3.62 e V）. It can therefore serve as a superior model for facile construction of functional polyolefin and soluble PTCBI polymer with ordered architecture.

关键词： Acyclic diene metathesis polymerization Hydrogenation Polyethylene Perylene bisimide