Research on the Collision-Free Path Planning of Multi-AGVs System Based on Improved A* Algorithm

Path planning problem is the core and hot research topic of multiple Automatic Guided Vehicles (multi-AGVs) system. Although there are many research results, they do not solve the path planning problem from the perspective of reducing traffic congestion. A collision-free path planning method based on improved A* Algorithm for multi-AGVs logistics sorting system is proposed in this paper. In the method, the environment of warehouse operation for AGVs is described by using grid method. The estimated cost of A* algorithm is improved by adding the penalty value of the paths that AGVs share with each other to alleviate traffic congestion and collision resolution rules are made according to different types of collisions. Then the collision-free path planning is done by combing the improved A* algorithm and collision resolution rules. The sorting efficiency of the method is compared with that of original A* algorithm. Simulation results show that the new collision-free path planning method can improve the sorting efficiency of multi-AGVs system and relieve traffic congestion.

The collision-free trajectory planning for the space robot to capture a target based on the wavelet interpolation algorithm

In the research of path planning for manipulators with many DOF, generally there is a problem in most traditional methods, which is that their computational cost (time and memory space) increases exponentially as DOF or resolution of the discrete configuration space increases. So this paper presents the collision-free trajectory planning for the space robot to capture a target based on the wavelet interpolation algorithm. We made wavelet sample on the desired trajectory of the manipulator’s end-effector to do trajectory planning by use of the proposed wavelet interpolation formula, and then derived joint vectors from the trajectory information of the end-effector based on the fixed-attitude-restrained generalized Jacobian matrix of multi-arm coordinated motion, so as to control the manipulator to capture a static body along the desired collision-free trajectory. The method overcomes the shortcomings of the typical methods, and the desired trajectory of the end-effector can be any kind of complex nonlinear curve. The algorithm is simple and highly effective and the real trajectory is close to the desired trajectory. In simulation, the planar dual-arm three DOF space robot is used to demonstrate the proposed method, and it shows that the algorithm is feasible.

May Fourth Movement in China-language Planning and Innovation

The purpose of this paper is to establish a clear comprehension and discernment of fundamental concepts of the languageplanning field and its correlation with and differences from innovation and change.It focuses on five aspects:a new language policyadopted in the period of late Qing;the status of classic Chinese in ancient times and the new vernacular in modern Chinese;the ori-gins of new vernacular;the problem that appeared alongside the new vernacularand the influence of May Fourth Movement in soci-ety and in education area.

Capitalist Planning？ The ＂Bombay Plan＂ as Contribution to Economic Debates Within the Indian National Movement, 1927-1945

The desire to draft a planning framework for India after independence was not only expressed by leftist groups. It was also on the agenda of business groups who published the Bombay Plan in 1944. Ideas of ＂economic nationalism＂, ＂state control＂, and ＂socialism＂ were attained from heterogeneous debates within the national movement and attached to a pro-capitalist agenda. This paper will explain the power relations behind the Bombay Plan, within the field of political forces of the Indian national movement. It shows their success in the strategy of co-operating with the Indian National Congress （INC） to impose their economic agenda. Secondly, it argues that there was a strong capitalist interest in planning.

Motion Planning Algorithm and Simulation for Space Manipulators

The specificities of collision-free path planning of space manipulators are analyzed. Path planning strategies are presented in consideration of these specificities, and an implementation procedure is also described in detail according to these strategies.

树、丘陵和没有红绿灯的丁字路 深圳华侨城的花园城市模式溯源

极具热带特征的丰富的多层次城市绿化、起伏有致的自然地形、人性化尺度的道路带来饶有趣味的步行体验、组团功能各异却共存共荣,这是深圳华侨城给人留下的第一印象,也是华侨城集团卓越的片区综合开发能力的展示。作为20世纪80年代中期由单一企业开发的知名“花园城市”、深圳的“城中之城”,深圳华侨城的空间特征的形成,既源于早期设计师和开拓者对自然的尊重与喜爱、对新加坡花园城市原型的追随、对桥头堡式良好投资环境的塑造,也源于经济地理条件的约束、旷日持久的土地产权谈判和开发时机的把握,以及规划方案对长期开发建设的弹性包容和整体把控。通过档案研究与访谈,文章力图总结80年代以来政治经济目标与设计理念互动之下的新城建设实践,并以深圳华侨城作为个案,探究其核心的花园城市设计的几个关键要素:城市绿化、自然的人工保留、路网和组团组织,以及城市性和公共性的生成。

基于具身智能的移动操作机器人系统发展研究

具身智能是新一轮科技革命与产业变革中的战略性技术,是当前世界各国重点竞争的前沿高地之一;移动操作机器人系统因其优秀的运动、规划、执行能力成为具身技术首选的硬件载体;基于具身智能的移动操作机器人系统作为实现跨领域、多场景、多功能的自主具身智能平台,将成为引领未来新一代信息技术和人工智能发展的关键。本文从基于具身智能的移动操作机器人系统发展的需求出发,总结了基于具身智能的移动操作机器人系统的发展现状,分析了该领域发展面临的问题和挑战,提出了涵盖多模态感知技术、世界认知与理解技术、智能自主决策技术、运动与操作联合规划技术等基于具身智能的移动操作机器人系统的共性关键技术。基于此,本文从国家政策倾斜、共性技术突破、交叉学科建设与人才培养、综合验证平台构建等方面提出了对策建议,以期助力具身智能发展浪潮下我国移动操作机器人领域的长足发展。

双机器人不同约束下的协调运动轨迹规划方法的研究

随着工业机器人在各行各业的广泛使用,单个机器人已不能满足大规模工件的搬运、复杂焊接和孔轴组装等要求。在双机器人的研究中,最重要的问题就是如何保证双机器人间的运动满足时间和空间约束,也就是双机器人的多重运动协调。文章用两台机械臂协同搬运和协同写字的实例分别分析了紧约束和松约束下的协同运动,对其运动学协调关系进行分析,通过工件或主体运动轨迹研究机器人约束关系,构建两双机协同体系;在Matlab中进行稳定性验证,并对所提出的理论进行可靠性验证。

基于改进RRT的清扫机器人全覆盖路径规划

针对钢筋轧制车间中大型非结构化环境下清扫机器人在全覆盖路径规划时所面临的算法运行成本高、避障性能差和区域覆盖率低等问题,提出了一种利用单元分解法分区覆盖和融合跳点搜索法的RRT区域转移的全覆盖路径规划算法。利用MCD(movement cell decomposition)算法实现自由区域覆盖,为了解决区域间路径规划时的避障问题,引入融合跳点搜索策略的RRT算法,通过增加节点扩展的导向性,使其更偏向目标区域进行搜索,并利用贪婪算法裁剪冗余点修正路径以及三次B样条曲线法平滑处理。通过仿真与实验验证了算法在不同环境下的可行性和有效性,相比于其他方法所规划的路径更短且大大降低了路径重复率,提高了机器人避障效率的同时实现了全区域路径覆盖。

桥梁检测机器人运动分析与运动规划研究

针对桥梁检测机器人对于高墩、高厚度桥梁不同部位的便捷检测需求,开展五自由度桥检机器人运动分析与运动规划研究。采用改进型D-H方法进行正向运动学建模,通过解析方法求解两种形式的运动学逆解,推导雅可比矩阵,分析机器人的奇异位型;通过蒙特卡洛方法得到机器人工作空间,确定工作空间可覆盖待检测区域;由连杆力与力矩平衡方程推导各关节受力关系,基于关节负载能力开展运动规划研究。仿真分析结果证明了方法的可行性,说明机器人能够完成预定的工作任务需求。

正颌外科规划软件中下颌运动交互模块的初步构建

目的:基于下颌运动轨迹构建数字化正颌外科规划软件中的下颌交互模块并进行临床验证。方法:基于CCMF Plan正颌规划软件,使用空间矩阵算法解算下颌运动轨迹数据,实现下颌运动的还原,根据距离重要性采样算法拟合患者个性化的下颌旋转轴并验证模拟下颌运动的精确性。使用下颌旋转轴指导手术规划,验证术中髁突位置实现的准确性。结果:开发出可再现患者下颌运动,以下颌旋转轴指导升支旋转的下颌运动交互模块。该模块还原模拟的下颌运动轨迹与真实轨迹误差约1 mm,同一开口度时的下颌骨模型表面距离均方根值(root mean square,RMS)值约0.3 mm。其指导的正颌手术术后髁突的角度偏差约为3°,距离偏差约1.5 mm。结论:该下颌运动交互模块可以较为精确地拟合下颌旋转轴,并还原患者个性化的下颌运动,术后髁突位置实现的精确性满足临床的要求。

腰椎融合术患者首次离床活动现况及影响因素调查

目的调查腰椎融合术患者术后首次离床活动现况,为后续制定针对性干预提供参考。方法采取便利抽样法,选取202例腰椎融合术患者,采用自行设计的问卷调查患者一般资料、手术相关情况及首次离床活动情况等。结果腰椎融合术后患者中32例(15.8%)进行了早期离床活动,首次离床活动时间为术后(44.0±4.2)h;术后24 h内伤口引流量、血红蛋白改变量、白蛋白改变量、引流管放置时间及恐动症评分是腰椎融合术患者首次离床活动时间的影响因素(均P<0.05)。结论腰椎融合术后患者首次离床活动比例较低,医护人员须重点关注其影响因素,制定和实施腰椎融合术患者离床活动方案,改善患者活动现况,促进术后康复。

路网约束下基于灰狼算法的机器人路径规划

机器人在规划路径时,由于初始路径群体数量多,且存在大量冗余个体,导致路径规划普遍存在效率低、可靠性不高等问题,为此设计一种路网约束下基于灰狼算法的机器人路径规划方法。利用多传感器采集车辆、环境等道路数据,推算车辆行驶速度、交通量及密度,使用信息守恒理论平滑计算交通数据,运用负指数函数构建证据理论信度,引入卡尔曼滤波器实现道路交通数据融合,构成完整路网架构;使用灰狼算法规划机器人路径,将狼群中适应度最高的3匹狼拟作头狼,通过搜寻猎物、包围猎物与进攻猎物来创建数学模型,更新灰狼方位了解其移动情况,完成机器人路径自适应规划。实验结果表明,所提方法时效性强,在静态、动态环境下均能实现机器人最优路径规划,且在动态环境下仅迭代4次就可找到最优路径,为机器人的高效率应用提供技术帮助。

全生命周期下文体融合的未来社区建设实践——以浙江省绍兴市棒球未来社区为例

在城镇化进程中,城镇人口的不断增长给社区建设带来诸多挑战,因此探索符合自身特点的建设路径,才能够实现社区的高效管理、资源共享及良性发展。本文着重探索在亚运会契机下、具有区位特征和城市特征的绍兴市棒球未来社区教育与运动相融合的特点,提出契合未来社区发展的文体融合路径,为今后未来社区的建设和发展提供参考。

Movement of Autonomous Vehicles in Work Zone Using New Pavement Marking: A New Approach

The autonomous vehicles are the future of mobility across the globe and are expected to touch the lives of every person of all ages. But this comes with certain challenges regarding safety, reliability, cost, legal framework, regulations, etc. however, of all the concern safety and reliability are of utmost importance for researchers and engineers. The current research is focused on the movement of the autonomous vehicle in the work zone. The work zone is one of the most challenging areas for the autonomous vehicle to drive from. This is because the work zones are very dynamic, and all the construction activities are specific to the site condition and cannot always be predefined. The study provides a concept of how pavement marking can be used for smooth movement through the complicated work zone. In this study, various pavement marking signs have been designed as a concept considering the standard colors and striping width being used in the Manual of Uniform Traffic control device (MUTCD). The study assumes that the movement of the autonomous vehicle will not be exclusive and that it will move with the driver driven vehicle. It is expected that autonomous vehicles will require special pavement marking and signage for smooth movement through the work zone. These pavement marking and signage will eventually become part of standard Traffic Control Plans (TCP) and Maintenance of Traffic Plans (MOT). The research aims to study the current research being done in this area and technology being used for detecting various pavement markings and signages.

基于改进RRT的采摘机械臂避障运动规划研究

针对传统RRT算法用于采摘机械臂避障路径规划上存在的搜索方向具有盲目性、搜索节点较多等问题,提出一种改进的RRT算法设计。首先,以Aubo-i5机械臂为实验主体,进行机械臂运动学分析,构建D-H参数表、机械臂三维模型,并采用包络法对机械臂进行碰撞检测;其次,对传统RRT算法进行优化策略改进,引入APF算法和广度优先搜索方法优化剪枝节点,进行算法流程分析;最后,使用RRT算法、RRT*算法、RRT-Connect算法和本文改进算法在不同场景的地图环境中进行运动规划,将改进算法用于机械臂避障抓取仿真实验。通过仿真实验结果表明,改进后的算法中节点搜索方向更准确、搜索节点变少、收敛速度更快,算法的效率的都得到大幅度的提升,验证了该算法的有效性和可靠性。

面向运动规划能力评估的脑电特征分析

运动规划涉及生活的方方面面,从拿起一个水杯到驾驶车辆时的应急处理,大脑无时无刻不在规划着运动的方式以获得最好的运动结果。运动规划能力的评估可以对运动员的选拔和运动规划障碍患者的诊断治疗提供重要的依据,但是传统的运动规划能力评估方法以行为学为主,经验不足的评估人员可能会得出不准确的结论。为了解决上述问题,本研究探索了基于脑电的运动规划能力评估方法,分别从时域、频域和非线性角度进行分析,提取了运动相关皮质电位(Movement-Related Cortical Potentials,MRCP)幅值,脑电功率谱密度(Power Spectral Density,PSD),脑电复杂度特征。通过相关性分析方法挖掘与行为学指标显著相关的脑电特征,发现FC4,C4及其周围导联的运动相关皮质电位幅值和反应时间呈显著负相关(FC4导联:ρ=-0.509,p=0.021;C4导联:ρ=-0.447,p=0.047),基于脑电功率谱密度计算的标准脑对称性指数(Standard Brain Symmetry Index,sBSI)和反应时间呈显著正相关(ρ=0.494,p=0.026),LZC(Lempel-Ziv Complexity)、模糊熵(Fuzzy Entropy,FuzzyEn)均与反应时间呈显著负相关(LZC:ρ=-0.626,p=0.015;FuzzyEn:ρ=-0.459,p=0.041)。研究结果表明MRCP幅值、sBSI、LZC和模糊熵可能成为评估运动规划能力的潜在生理靶标。综上,本研究结果有望为运动规划能力的评估提供方法学指导。

基于动态运动基元的机器人电子元器件装配轨迹规划方法研究

针对电子元器件装配任务中电子元器件和PCB板种类较多,以及生产过程中产品种类更换频繁所导致的装配轨迹多变等问题,提出一种基于动态运动基元的机器人轨迹规划方法。首先,建立动态运动基元系统方程,对机器人的运动进行建模;其次,根据演示轨迹对非线性函数的参数进行学习,利用非线性最优化的局部加权回归方法求得演示轨迹的权重系数;然后,对方程中的非线性函数项进行分段加权,使系统能够稳定收敛到目标装配点;最后,设计具有末端姿态约束的机器人拖动算法在Panda机器人上进行轨迹演示,根据目标位姿不发生变化与发生变化两种情况生成机器人的自主装配轨迹,并在Panda机器人上对三种不同的电子元器件进行装配验证。结果表明:基于改进后的动态运动基元方法学习到的机器人运动轨迹,不仅能够很好地模仿演示轨迹的运动趋势,而且可以以较高的精度到达目标指定位姿,很好地完成了机器人电子元器件装配任务。

Bio-inspired motion planning for reaching movement of a manipulator based on intrinsic tau jerk guidance

This study proposed a bio-inspired motion planning approach for the reaching movement of a robot manipulator based on a novel intrinsic tau jerk guidance strategy,which was established by some cognitive science researchers when they studied motion patterns through biology.In accordance with the rules of human reaching movement,the intrinsic tau jerk guidance strategy ensures continuity of the acceleration;further,it also ensures that its value is zero at the start and end of the movement.The approach has been implemented on a three-degrees-offreedom 3R planar manipulator.The results show that,within a defined time,both the position gap and attitude gap can be reposefully closed,and the curves of joint velocity,acceleration,and driving torque are continuous and smooth.According to the dynamic analysis,the proposed approach tends to consume less energy.The bioinspired method has the potential to be applied in particular scenarios in the future,such as a mobile robot with a manipulator exploring an unknown environment.

中小组立弧线焊缝机器人轨迹规划

为解决目前机器人自动化焊接尚不能覆盖复杂结构件弧缝的问题,基于运动学建模、机器人轨迹规划等方法,开展中小组立弧线焊缝机器人仿真与试验、软件总体设计、人机交互设计、工作站设计。研究表明:中小组立弧线焊缝机器人可有效覆盖复杂结构件的弧缝,焊接效率相较人工焊提升50%。研究成果可为机器人自动化焊接设计提供一定参考。