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Artificial coordinating field and its application to motion planning of robots in uncertain dynamic environments

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Science China(Technological Sciences) 2004年第5期47卷 577-594页

作者： JING Xingjian1, 2, WANG Yuechao1 & TAN Dalong1 1. Robotics Laboratory, Shenyang Institute of Automation, Chinese Academy of Sciences, Shenyang 110016, China 2. Graduate School, Chinese Academy of Sciences, Beijing 100039, China Correspondence should be addressed to Jing Xingjian Robotics Laboratory Shenyang Institute of Automation Chinese Academy of Sciences Graduate School Chinese Academy of Sciences

Artificial coordinating fields (ACF) are proposed to deal with the motion planning problems of mobile robots in uncertain dynamic environments. An ACF around an obstacle can generate two orthogonal force vectors to a robot: one is called the coordinating force vector which is purposively designed in this paper, and the other is the repulsive force vector which is the same as that in a conventional artificial potential field. The ACF is designed according to the updated motion purpose and the relative states of the robot with respect to its local environment, and it also satisfies the robot’s dynamic constraints. The direction of the coordinating force can be determiend on line according to an optimal evaluation function. The ACF can effectively remove the local minima, and reduce the oscillation of the planned trajectory between multiple obstacles. Only local knowledge of the environments is needed in the ACF-based motion planning. The properties of the ACF such as controllability, adaptability, safety and reachability are studied and discussed in detail in this paper. Theoretical analysis and simulations are given to illustrate our main results.

关键词： artificial coordinating fields, artificial potential fields, mobile robots, motion planning, uncertain dynamic environments.

Adjoint method for the optimum planning of industrial pollutant sources

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Science China Earth Sciences 2005年第8期48卷 1270-1279页

作者： LIU Feng1,2, HU Fei2 & ZHU Jiang2 1. College of Environmental Sciences, Peking University, Beijing 100871, China 2. LAPC, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China College of Environmental Sciences Peking University Beijing China LAPC Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China

The optimum planning of industrial pollutant sources, which optimizes the economic object without violating environmental constraints, is an important and hard task to be conquered. In this paper, an adjoint method is developed to solve the problem. The penalty function is in-troduced to deal with the environmental inequality constraints, and Lagrange function is con-structed to derive the adjoint equation and the gradient of the object function. In this means, the gradient of the object function can be calculated by solving the adjoint equation, and the infor-mation from the gradient is used to make the object function descend and approach to an optimal solution after some iterations. A two-dimensional, simplified model is used for numerical experi-ments. The theoretical derivations are verified by the results of the experiments. Furthermore, the adjoint method is shown to be of excellent convergence and efficiency, which is adaptive to the fast development of air quality numerical models and super computers.

关键词： optimum planning, industrial pollutant sources, adjoint equation, penalty function, gradient.

Immune and Genetic Algorithm Based Assembly Sequence planning

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Journal of Donghua University(English Edition) 2004年第6期21卷 38-42页

作者：杨建国李蓓智俞雷金宇松 College of Mechanical Engineering Dong Hua University Shanghai 200051professor College of Mechanical Engineering Dong Hua University Shanghai 200051

In this paper an assembly sequence planning model inspired by natural immune and genetic algorithm (ASPIG) based on the part degrees of freedom matrix (PDFM) is proposed, and a proto system — DSFAS based on the ASPIG is introduced to solve assembly sequence problem. The concept and generation of PDFM and DSFAS are also discussed. DSFAS can prevent premature convergence, and promote population diversity, and can accelerate the learning and convergence speed in behavior evolution problem.

关键词： assembly, assembly sequence, automatic planning, immune algorithm, genetic algorithm

Effect of Splice Marking on Fabric Roll planning

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Journal of Donghua University(English Edition) 2001年第3期18卷 70-74页

作者：吴秀芬许赐亮陈建中 Institute of Textiles and Clothing The Hong Kong Polytechnic University Department of Computing The Hong Kong Polytechnic University

Minimising the fabric loss during spreading can reduce the total production costs of garment *** marker planning is a major determinant of material utilisation, considerable savings on materials also will be made from the area of spreading loss. In the spreading process, it is general to have variance on the fabric yardage between each fabric roll, and the number of splice markings on each cutting lay is also varied. This paper aim to study how the fabric roll planning and the number of splice marks of a cutting lay will affect the material usage in the spreading process. By using a genetic algorithm approach, the amount of fabric to be saved by optimising the fabric roll sequence was derived by comparing the best arrangement and the worst arrangement of the fabric roll sequences of a cutting *** result of the study showed that both fabric roll planning and the number of splice marking have effect on the fabric loss. The findings could help the apparel manufacturer to reduce the fabric loss by improving the roll planning in fabric spreading.

关键词： roll planning, genetic algorithms, garment manufacturing.

Research and application on the technology system of multi-scale assessment of the impact on the atmospheric environment by urban planning

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Science China Earth Sciences 2005年第Z2期48卷 173-184页

作者： WANG Guangtao, WANG Xiaoyun, MIAO Shiguang, JIANG Weimei, GUO Wenli, JI Chongping & CHEN Xianyan School of Architecture, Tsinghua University, Beijing 100084, China Ministry of Construction of China, Beijing 100044, China Beijing Meteorological Bureau, Beijing 100089, China Institute of Urban Meteorology, China Meteorological Administration, Beijing 100089, China Department of Atmospheric Sciences, Nanjing University, Nanjing 210093, China School of Architecture Tsinghua University Beijing 100084 China Ministry of Construction of China Beijing 100044 China School of Architecture Tsinghua University Beijing 100084 China Beijing Meteorological Bureau Beijing 100089 China Institute of Urban Meteorology China Meteorological Administration Beijing 100089 China Department of Atmospheric Sciences Nanjing University Nanjing 210093 China Beijing Meteorological Bureau Beijing 100089 China

Improvement of the atmospheric environment in urban planning is an important issue to implement the sustainable development of cities. In this paper, in order to meet the demand of planning office to compare and assess quantitatively of the designs in multi-scale, based on geographical information system (GIS) data with high resolution, a multi-scale numerical modeling system for the atmospheric environment impact of urban planning is set up, and the multi-scale assessment index system is established, which compose the technology system of multi-scale assessment of the impact on the atmospheric environment by urban planning. In urban planning (urban development of Beijing) and optimizing layouts of Olympic Green, it has been applied to quantitatively evaluating the impact on atmospheric environment by urban planning before construction, which offers scientific foundation to optimize the whole and local urban layout.

关键词： urban planning, atmospheric environment, multi-scale, numerical simulation, assessment index system.

Pseudo minimum translational distance between convex polyhedra (Ⅱ)——Robot collision-free path planning

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Science China(Technological Sciences) 2001年第4期44卷 337-344页

作者：朱向阳丁汉熊有伦

By using the pseudo minimum translational distance between convexobjects, this paper presents two algorithms for robot path planning. First, an analytically tractable potential field is defined in the robot configuration space, and the concept of virtual obstacles is introduced and incorporated in the path planner to handle the local minima of the potential function. Second, based on the Lipschitz continuity and differentiability of the pseudo minimum translational distance, the flexible-trajectory approach is implemented. Simulation examples are given to show the effectiveness and efficiency of the path planners for both mobile robots and manipulators.

关键词： robot path planning, pseudo minimum translational distance, potential field, virtual obstacle, flexible-trajectory approach.

Effective Implementation of Urban planning

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Journal of Donghua University(English Edition) 2002年第2期19卷 119-121页

作者：王训国 College of Information Science & Technology Dong Hua University Shanghai200051

We analyze the factors that affect the efficiency and function of city planning in practical implementation, especially those of detailed planning. Two key principles and three strategies for plan to reach effective i... 详细信息

关键词： urban planning, detailed planning, implementation

A TQCS-based Scheduling Approach for Manufacturing Grid

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Journal of Donghua University(English Edition) 2004年第6期21卷 43-48页

作者：刘丽兰俞涛曹红武施战备 CIMS & Robot Center of Shanghai University Shanghai 200072

With Open Grid Service Architecture (OGSA) as system framework, and Globus Toolkit3.0 (GT3) as developing tools, Manufacturing Grid (MG) is proposed in this research to realize resource sharing and collaborative working among manufacturing resources, and task scheduling is one of the most critical components in this system. Nevertheless, the Globus Resource Allocation Manager (GRAM) does not provide scheduling system by default, and traditional performance-guided or economy-guided schedulers cannot satisfy our needs in MG. So, in this paper, a TQCS (Time, Quality, Cost, Service)-based scheduling approach is presented and the corresponding scheduler (Manufacturing Grid Task Scheduler, MGTS) is implemented with the functions of Global Process planning (GPP) analyzing, resource discovery, resource selection, AHP (Analytic Hierarchy Process)-based resource mapping, and fault-tolerant handling. Furthermore, the application architecture is depicted at the end of the paper to illustrate the utilization of our scheduler.

关键词： Open Grid Service Architecture (OGSA), Manufacturing Grid, Task Scheduling, Global Process planning, Analytic Hierarchy Process (AHP)