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冻融循环作用下MICP固化铅污染土的强度与浸出特性研究

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工程地质学报 2024年第2期32卷 440-447页

作者：李杰康博查甫生合肥工业大学资源与环境工程学院合肥230000

微生物诱导碳酸钙沉淀(MICP)技术可用于重金属污染土固化稳定修复。本文通过开展无侧限抗压强度、离子浸出及微观试验,主要研究MICP固化铅污染土在冻融循环作用下的强度与化学稳定性,并揭示其微观作用机理。结果表明:随着铅离子浓度的增... 详细信息

微生物诱导碳酸钙沉淀(MICP)技术可用于重金属污染土固化稳定修复。本文通过开展无侧限抗压强度、离子浸出及微观试验,主要研究MICP固化铅污染土在冻融循环作用下的强度与化学稳定性,并揭示其微观作用机理。结果表明:随着铅离子浓度的增加,土体的无侧限抗压强度先增大后减小,铅离子浸出浓度增大;随冻融循环次数的增加,土体的强度逐渐降低并趋于稳定,铅离子浸出浓度增大。冻融循环作用后,固化土的主要矿物成分未发生变化;土中的小孔隙数量增加,大孔隙数量基本保持不变。冻融循环作用损伤固化土的碳酸钙胶结与铅离子沉淀结构,致使土体性能劣化。

关键词：重金属污染土微生物诱导碳酸钙沉淀(MICP) 冻融循环强度及浸出特性劣化机理

基于可调场景语义标注范围的家庭室内语义地图构建

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中国惯性技术学报 2024年第4期32卷 371-378页

作者：张淑珍何镇查富生侯致远马玉祥兰州理工大学机电工程学院兰州730000 哈尔滨工业大学机器人技术与系统国家重点实验室哈尔滨150001

针对家庭室内环境语义地图建图速度较慢和在门口场景语义标注易出现错误等问题,提出一种基于可调场景语义标注范围的家庭室内语义地图构建方法。首先根据YOLOv5s识别的物体大小赋予相应的场景置信度,基于该场景置信度设置阈值使得语义... 详细信息

针对家庭室内环境语义地图建图速度较慢和在门口场景语义标注易出现错误等问题,提出一种基于可调场景语义标注范围的家庭室内语义地图构建方法。首先根据YOLOv5s识别的物体大小赋予相应的场景置信度,基于该场景置信度设置阈值使得语义标注范围限制在机器人当前所在区域,确保场景切换时语义标注范围不会立即改变。然后基于人工势场虚拟力“引力斥力”原理,实现语义标注范围的扩大或缩小。最后结合阈值和动态语义标注范围,避免在门口场景中出现语义标注错误。实验结果表明:与Places205-VGG16神经网络建立家庭室内语义地图相比,所提方法平均效率和平均精准率分别提升了11.0%和7.8%,在家庭室内环境中具有一定的优越性。

关键词：家庭室内环境语义地图场景识别模型场景置信度变语义标注范围

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膨胀土收缩过程中的微结构变化定量分析

山西建筑 2024年第7期50卷 78-81页

作者：孙寒星王兴查甫生中铁二十四局集团安徽工程有限公司安徽合肥230011 合肥工业大学资源与环境工程学院安徽合肥230009

针对黏性土结构定量研究中存在的困难以及现有的土的结构性研究方法所存在的不足,引入能同步反映土的微结构变化的电阻率方法。进行了膨胀土的收缩试验,并同步测定了竖向电阻率。通过研究土样失水收缩过程中的土电阻率的变化规律,建立... 详细信息

针对黏性土结构定量研究中存在的困难以及现有的土的结构性研究方法所存在的不足,引入能同步反映土的微结构变化的电阻率方法。进行了膨胀土的收缩试验,并同步测定了竖向电阻率。通过研究土样失水收缩过程中的土电阻率的变化规律,建立描述膨胀土收缩过程中微结构变化的电阻率评价方法。结果表明,膨胀土的收缩性与电阻率之间存在良好的相关关系,可以通过分析电阻率的变化来研究膨胀土胀缩性变化。根据土电阻率随收缩时间及线缩率的变化规律,可将膨胀土的收缩过程划分为三个不同阶段:初始收缩阶段、主收缩阶段和次收缩阶段。

关键词：电阻率膨胀土微结构定量分析

CPG Control for Biped Hopping Robot in Unpredictable Environment

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Journal of Bionic Engineering 2012年第1期9卷 29-38页

作者： Tingting Wang Wei Guo Mantian Li fusheng zha Lining Sun State Key Laboratory of Robotics and System Harbin Institute of TechnologyHarbin 150080P.R.China

A CPG control mechanism is proposed for hopping motion control of biped robot in unpredictable environment. Based on analysis of robot motion and biological observation of animal＇s control mechanism, the motion control task is divided into two simple parts： motion sequence control and output force control. Inspired by a two-level CPG model, a two-level CPG control mechanism is constructed to coordinate the drivers of robot joint, while various feedback information are introduced into the control mechanism. Interneurons within the control mechanism are modeled to generate motion rhythm and pattern promptly for motion sequence control; motoneurons are modeled to control output forces of joint drivers in real time according to feedbacks. The control system can perceive changes caused by unknown perturbations and environment changes according to feedback information, and adapt to unpredictable environment by adjusting outputs of neurons. The control mechanism is applied to a biped hopping robot in unpredictable environment on simulation platform, and stable adaptive motions are obtained.

关键词： biped robot unpredictable environment hopping motion control bionic control CPG

A Parallel Actuated Pantograph Leg for High-speed Locomotion

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Journal of Bionic Engineering 2017年第2期14卷 202-217页

作者： Wei Guo Changrong Cai Mantian Li fusheng zha Pengfei Wang Kenan Wang State Key Laboratory of Robotics and System Harbin Institute of Technology Harbin 150001 China

High-speed running is one of the most important topics in the field of legged robots which requires strict constraints on structural design and control. To solve the problems of high acceleration, high energy consumption, high pace frequency and ground impact during high-speed movement, this paper presents a parallel actuated pantograph leg with an approximately decoupled configuration. The articulated leg features in light weight, high load capacity, high mechanical efficiency and structural stability. The similarity features of force and position between the control point and the foot are analyzed. The key design parameters, K1 and K2, which concern the dynamic performances, are carefully optimized by comprehensive evaluation of the leg inertia and mass within the maximum foot trajectory, A control strategy that incorporates virtual Spring Loaded Inverted Pendulum （SLIP） model and active force is also proposed to test the design. The strategy can implement highly flexible impedance without mechanical springs, which substantially simplifies the design and satisfies the variable stiffness requirements during high-speed running. The rationality of the structure and the effectiveness of the control law are validated by simulation and experiments.

关键词： high-speed parallel actuated pantograph leg optimization virtual SLIP model active force

Squeezing More Past Knowledge for Online Class-Incremental Continual Learning

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IEEE/CAA Journal of Automatica Sinica 2023年第3期10卷 722-736页

作者： Da Yu Mingyi zhang Mantian Li fusheng zha Junge zhang Lining Sun Kaiqi Huang the State Key Laboratory of Robotics and System Harbin Institute of Technology(HIT)Harbin 150080China Center for Research on Intelligent System and Engineering Institute of AutomationChinese Academy of Sciences(CASIA)Beijing 100190 School of Artificial Intelligence University of Chinese Academy of SciencesBeijing 100049China Center for Research on Intelligent System and Engineering Institute of AutomationChinese Academy of Sciences(CASIA)Beijing 100190the School of Artificial IntelligenceUniversity of Chinese Academy of SciencesBeijing 100049 the CAS Center for Excellence in Brain Science and Intelligence Technology Shanghai 200031China IEEE

Continual learning(CL)studies the problem of learning to accumulate knowledge over time from a stream of data.A crucial challenge is that neural networks suffer from performance degradation on previously seen data,known as catastrophic forgetting,due to allowing parameter *** this work,we consider a more practical online class-incremental CL setting,where the model learns new samples in an online manner and may continuously experience new ***,prior knowledge is unavailable during training and *** works usually explore sample usages from a single dimension,which ignores a lot of valuable supervisory *** better tackle the setting,we propose a novel replay-based CL method,which leverages multi-level representations produced by the intermediate process of training samples for replay and strengthens supervision to consolidate previous ***,besides the previous raw samples,we store the corresponding logits and features in the ***,to imitate the prediction of the past model,we construct extra constraints by leveraging multi-level information stored in the *** the same number of samples for replay,our method can use more past knowledge to prevent *** conduct extensive evaluations on several popular CL datasets,and experiments show that our method consistently outperforms state-of-the-art methods with various sizes of episodic *** further provide a detailed analysis of these results and demonstrate that our method is more viable in practical scenarios.

关键词： Catastrophic forgetting class-incremental learning continual learning(CL) experience replay

Robot Navigation Strategy in Complex Environment Based on Episode Cognition

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Journal of Bionic Engineering 2023年第1期20卷 1-15页

作者： Jinsheng Yuan Wei Guo Zhiyuan Hou fusheng zha Mantian Li Lining Sun Pengfei Wang State Key Laboratory of Robotics and System Harbin Institute of Technology(HIT)Harbin150001China Shenzhen Academy of Aerospace Technology Shenzhen518057China School of Mechanical and Electrical Engineering Lanzhou University of TechnologyLanzhou730050China

The hippocampal formation of the brain contains a series of nerve cells related to environmental cognition and *** cells can integrate their moment information and external perceptual information and acquire episodic cognitive *** episodic cognition and memory,organisms can achieve autonomous navigation in complex *** paper mainly studies the strategy of robot episode navigation in complex *** exploring the environment,the robot obtains subjective environmental cognition and forms a cognition *** grid cells information contained in the cognitive map can obtain the direction and distance of the target through vector calculation,which can get a shortcut through the inexperienced *** synaptic connection of place cells in the cognitive map can be used as the topological relationship between episode *** the target-oriented vector navigation encounters obstacles,the obstacles can be realized by setting closer *** on the known obstacle information obtained from boundary cells in the cognitive map,topological paths can be divided into multi-segment vector navigation to avoid encountering *** paper combines vector and topological navigation to achieve goal-oriented and robust navigation capability in a complex environment.

关键词： Bionic intelligent.Grid cell-Hippocampus-Navigation strategy Episode cognition

Force-controlled Compensation Scheme for P-Q Valve-controlled Asymmetric Cylinder used on Hydraulic Quadruped Robots

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Journal of Bionic Engineering 2020年第6期17卷 1139-1151页

作者： Yapeng Shi Mantian Li fusheng zha Lining Sun Wei Guo Cong Ma Zhibin Li State Key Laboratory of Robotics and System Harbin Institue of TechnologyHarbin 150001China Shenzhen Academy of Aerospace Technology China Aerospace ScienceShenzhen 518057China School of Informatics The University of EdinburghEdinburgh EH89ABUnited Kingdom

Under the requirement of the force controller of hydraulic quadruped robots,the goal of this work is to accurately track the force commands at the level of the hydraulic drive *** main contribution focuses on the development of a force-controlled compensation scheme,which is specifically aimed at the key issues affecting the hydraulic quadrupedal *** this idea,based on a P-Q valve-controlled asymmetric cylinder,we first establish a mathematical model for the hydraulic drive unit force control *** the desired force commands,a force feed-forward algorithm is presented to improve the dynamic performance of the ***,we propose a disturbance compensation algorithm to reduce the influence induced by external disturbances due to foot-ground ***,combining with a variable gain PI controller,a series of experiments are implemented on a force control performance test platform to verify the proposed *** results demonstrate that the force-controlled compensation scheme has the ability to notably improve the force tracking accuracy,reduce the response time and redundant force.

关键词： hydraulic drive unit force tracking P-Q valve-controlled asymmetric cylinder hydraulic quadruped robot

Design and analysis of a whole-body controller for a velocity controlled robot mobile manipulator

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Science China(Information Sciences) 2020年第7期63卷 98-112页

作者： Mantian LI Zeguo YANG fusheng zha Xin WANG Pengfei WANG Ping LI Qinyuan REN Fei CHEN State Key Laboratory of Robotics and Systems Harbin Institute of Technology Shenzhen Academy of Aerospace Technology Key Laboratory of Industrial Control Technology Zhejiang University

Mobile manipulators, which are intrinsically redundant when the manipulator and mobile base are moving together, are known for their capabilities to carry out multiple tasks at the same time. This paper presents a whole-body control framework, inspired by legged bio-robots, for a velocity controlled non-holonomic mobile manipulator based on task priority. Control primitives, such as manipulability optimization, trajectory tracking of the end-effector and mobile base, and collision avoidance, are considered in the framework and arranged at different priorities. Lower priority tasks are projected into the null space of control tasks with higher priorities. As a result, lower level tasks are completed without affecting the performance of higher priority tasks. Several experiments are implemented to verify the effectiveness of the proposed controller. The proposed method is proved to be an effective way to solve the whole-body control problem of velocity controlled mobile manipulators.

关键词： mobile manipulator whole-body control velocity controlled task priority null-space projection