弯扭耦合型软体机器人智能感知抓取性能研究

触觉感知功能对于生物或机器人进行目标物体的智能感知与抓取具有重要意义。首先，研究设计了一种新型弯扭耦合型软体机器人，并将压力传感器和弯曲传感器嵌入设计在软体机器人底层；其次，组合设计了能够感知抓取目标物体信息的二指软体夹爪；第三，搭建了二指软体夹爪抓取性能实验测试平台，系统分析了二指软体夹爪在抓取不同目标物体时的指尖触觉信息；最后，对生活中常见的12种物体进行了抓取性能测试，获得了不同压力下的压力序列信号并建立了抓取数据集，还采用多种机器学习算法对触觉数据集进行分类研究。结果表明：设计方案能够成功识别出目标物体的真实情况，其中随机森林分类算法具有最优的分类效果，准确率达到了93.33%。该研究有望为智能软体机器人的设计和智能抓取提供一定的理论和技术支持。     

一种针对单快拍DOA估计的子空间搜索近似消息传递算法

压缩感知（Compressed sensing,CS）技术应用于单快拍波达方向（Direction of arrival,DOA）估计中可以实现相关信号的超分辨估计,但会遇到感知矩阵高相干性以及对噪声敏感的问题.本文提出一种基于近似消息传递的子空间搜索算法以解决上述问题.该算法首先通过近似消息传递算法得到一个粗解,随后利用该粗解划分子空间,最后在子空间中寻找精确解.仿真结果验证了所提算法的有效性.文章最后通过理论分析了该算法性能并讨论了算法在信号数未知时的扩展应用.     

基于雷达与视觉融合的双模态煤矿井下环境感知技术

环境感知是煤矿巡检机器人、视觉测量系统等场景应用的关键技术。单模态环境感知技术对煤矿井下复杂环境的感知能力较差。提出了雷达与视觉双模态空间融合方法,通过激光雷达和摄像仪之间的坐标转换来实现二者采集信息的融合,从而提高环境感知能力。为了更好地提取目标特征信息,提出了双模态融合环境感知网络架构技术路线：摄像仪和雷达采集的环境信息经雷达与视觉双模态空间融合方法进行融合处理,多模态特征融合网络模块提取融合信息中的目标特征,多任务处理网络模块采用不同的任务头处理目标特征信息,完成目标检测、图像分割、目标分类等环境感知任务。采用YOLOv5s目标检测算法搭建双模态特征提取网络模块进行实验,结果表明：基于雷达与视觉融合的双模态煤矿井下环境感知技术对井下巷道环境下行人检测的成功率较视觉、雷达感知分别提升15%,10%,对车道线、标志牌等各类目标分割的平均精度均值较视觉感知均提高10%以上,有效提升了煤矿井下环境感知能力,可为煤矿道路环境感知、视觉测量系统、无人矿车导航系统、矿井搜救机器人等应用场景提供技术支持。     

基于改进SP算法的压缩感知图像重构

针对压缩感知子空间追踪SP(subspace pursuit)算法必须以信号稀疏度为先验知识,而现实中图像稀疏度未知这一问题,提出改进SP算法MSP(modified subspace pursuit)。首先对信号的稀疏度进行自适应估计,其次在迭代过程中,通过给定的步长因子对稀疏度进行更新,使之逐渐逼近正确子空间,当重构误差小于阈值时,停止迭代,实现稀疏信号的重构。重构图像表明:MSP算法在运算时间和重构精度上均优于其他同类算法,实现了图像的快速精确重构。     

基于知识空间的多级感知空间处理技术研究

在网络协同化学习环境中,由于学习环境比较复杂,解决学习者在学习过程中的"孤独感"问题以提高网络环境的社会性,对于学习者顺利完成学习任务来说显得非常重要.在CSCW的感知处理技术的基础上,基于知识空间理论和知识域间关系模型,利用学习者的兴趣模型和能力模型,提出了多学习内容、多学习目标、多学习等级的动态多级感知空间模型,在学习者的学习过程中,通过灵活的感知处理技术和感知敏感度调节,为学习者感知到其他学习者的信息和行为,为寻求或是提供其他学习者的交流和指导,共同完成学习任务提供了有效的途径.     

基于一种蚁群算法的多机器人动态感知任务分配

多机器人系统在具有任务聚集特征的动态感知任务环境下执行搜集任务时,存在着由于任务分配不当而引起的冲突加剧问题.针对这一问题,提出了一种基于排斥信息素型蚁群算法的多机器人任务自主分配方法.进行了未知非结构化环境下的多机器人协作搜集仿真实验.仿真结果表明,采用本文所提方法可以实现多机器人搜集任务的自主分配,有效减少机器人的空间冲突,尤其在机器人数量较多的情况下,更能显示出该方法的优势.     

一种仿生触须传感器的设计与分析

为了增强机器人对未知环境的感知与识别能力,设计了一种基于霍尔效应的仿生触须传感器。针对该传感器建立了触须感知模型,并在此基础上进行仿真实验,分析触须轴的不同材质和长度对触须传感器感知结果的影响。同时,提出了可通过触须的偏转幅度来估计目标物距离和角度位置的被动和主动感知方法。实验结果表明：利用该触须传感器能够快速、准确地感知外界环境信息。     

一种自适应正则化子空间追踪算法

针对压缩感知中未知稀疏度信号的重建问题,提出一种新的压缩感知的信号重建算法,即自适应正则化子空间追踪（Adaptive Regularized Subspace Pursuit,ARSP）算法,该算法将自适应思想、正则化思想与子空间追踪（Subspace Pursuit,SP）算法相结合,在未知信号稀疏度的情况下,自适应地选择支撑集原子的个数,利用正则化过程实现支撑集的二次筛选,最终能实现信号的精确重构。仿真结果表明,该算法能够精确重构原始信号,重建效果优于SP算法、正则化正交匹配追踪（ROMP）算法、稀疏度自适应匹配追踪（SAMP）算法、压缩采样匹配追踪（CoSaMP）算法等。     

基于二维压缩感知的超声k空间重建

压缩感知理论已经应用于多个领域,如MRI,超声等。提出了一个新的超声重建方法,基于二维压缩感知和k空间。在时域采样特定信号,并在k空间中对其进行重建。当处理二维信号(图像)时,传统的方法是将其转换为一维向量,这种方法非常耗时,并且对于大的图像重建来说不切实际,通过二维压缩感知处理这个难题。     

如何解决基不匹配问题:从原子范数到无网格压缩感知

压缩感知理论能够以远低于经典Nyquist速率进行采样, 采用非自适应线性投影获得了保留信号有用信息的少量观测点, 并通过求解最优化问题精确重构原始信号.压缩感知理论大大缓解了信号采样、存储和传输的巨大压力, 在计算机科学、电子工程和信号处理等领域具有广阔的应用前景.信号的稀疏表示是对信号进行压缩采样和重构的前提, 即假设信号在某个变换基(傅里叶基、小波基等)下是稀疏的, 这些基可以看作是用于描述信号参数空间的有限离散字典.然而在如雷达、阵列信号处理、通信等领域的应用中, 信号的参数空间是连续的, 在假定的离散变换基下并不稀疏, 这种基不匹配问题会严重影响信号重构精度.本文首先介绍了基不匹配产生的原因及其对重构精度的影响, 接着从原子范数出发, 综述了无网格压缩感知的理论框架和关键技术问题, 着重介绍了一维和多维无网格压缩感知的最新研究进展, 最后对其在信号处理等领域的应用进行了探讨.     

可持续发展战略的资源遥感回顾与展望

对遥感技术在土地利用变化、空间信息资源调查、水土流失动态监测、海洋环境监测、自然灾害监测与防治、生物量估测、环境污染监测等目前可持续发展核心热点问题的研究、应用、进展进行了讨论;对现阶段的研究方法及成果做了回顾与评价。认为遥感技术的发展与成熟,将会为可持续发展战略目标提供更大的发展空间,在局部和全球,必将成为不可或缺的应用技术之一。     

Development of A Behavior‐Based Cooperative Search Strategy for Distributed Autonomous Mobile Robots Using Zigbee Wireless Sensor Network

To achieve efficient and objective search tasks in an unknown environment, a cooperative search strategy for distributed autonomous mobile robots is developed using a behavior‐based control framework with individual and group behaviors. The sensing information of each mobile robot activates the individual behaviors to facilitate autonomous search tasks to avoid obstacles. An 802.15.4 ZigBee wireless sensor network then activates the group behaviors that enable cooperative search among the mobile robots. An unknown environment is dynamically divided into several sub‐areas according to the locations and sensing data of the autonomous mobile robots. The group behaviors then enable the distributed autonomous mobile robots to scatter and move in the search environment. The developed cooperative search strategy successfully reduces the search time within the test environments by 22.67% (simulation results) and 31.15% (experimental results).     

遥感图像时空融合综述

高时空分辨率的遥感图像大数据在遥感领域发挥着重要作用.然而,由于技术上和预算上的限制等原因,目前单一的卫星传感器无法获取同时具有高空间分辨率和高时间分辨率的遥感影像.因此遥感图像时空融合技术被认为是解决时间分辨率和空间分辨率折衷问题的有效途径之一.随着深度学习在各领域的广泛应用,深度学习技术已经被证实是解决图像问题非常...     

Classifying Environmental Features From Local Observations of Emergent Swarm Behavior

Robots in a swarm are programmed with individual behaviors but then interactions with the environment and other robots produce more complex, emergent swarm behaviors. One discriminating feature of the emergent behavior is the local distribution of robots in any given region. In this work, we show how local observations of the robot distribution can be correlated to the environment being explored and hence the location of openings or obstructions can be inferred. The correlation is achieved here with a simple, single-layer neural network that generates physically intuitive weights and provides a degree of robustness by allowing for variation in the environment and number of robots in the swarm. The robots are simulated assuming random motion with no communication, a minimalist model in robot sophistication, to explore the viability of cooperative sensing. We culminate our work with a demonstration of how the local distribution of robots in an unknown, office-like environment can be used to locate unobstructed exits.      

遥感技术在毒草识别中的研究进展

毒草的滋生蔓延严重破坏草地生境,制约草地畜牧业的发展。遥感技术作为牧场管理的一种重要的技术手段,其传感器自身的空间分辨率和光谱分辨率的高低是决定毒草识别成功与否的关键。于毒草独特的物候特征出现时获取影像数据能帮助提高分类识别的精度。回顾了3种遥感技术在毒草识别中的研究进展。航空摄影成本高、数据处理复杂,难于得到推广 ;多光谱卫星遥感大多空间分辨率低,仅在识别大面积滋生、密度较大的毒草方面展现出了一定的潜力 ;高光谱遥感的出现改善了对植被分类识别的精度,是未来毒草识别的主要依据。由于高光谱数据的冗余性和复杂性,数据处理技术和分类方法的选择也是影响毒草识别精度的重要因素。     

Unearthing the Infrastructure: Humans and Sensors in Field-Based Scientific Research

Distributed sensing systems for studying scientific phenomena are critical applications of information technologies. By embedding computational intelligence in the environment of study, sensing systems allow researchers to study phenomena at spatial and temporal scales that were previously impossible to achieve. We present an ethnographic study of field research practices among researchers in the Center for Embedded Networked Sensing (CENS), a National Science Foundation Science & Technology Center devoted to developing wireless sensing systems for scientific and social applications. Using the concepts of boundary objects and trading zones, we trace the processes of collaborative research around sensor technology development and adoption within CENS. Over the 10-year lifespan of CENS, sensor technologies, sensor data, field research methods, and statistical expertise each emerged as boundary objects that were understood differently by the science and technology partners. We illustrate how sensing technologies were incompatible with field-based environmental research until researchers “unearthed” their infrastructures, explicitly reintroducing human skill and expertise into the data collection process and developing new collaborative languages that emphasized building dynamic sensing systems that addressed human needs. In collaborating around a dynamic sensing model, the sensing systems became embedded not in the environment of study, but in the practices of the scientists.     

Efficient exploration of unknown indoor environments using a team of mobile robots

Whenever multiple robots have to solve a common task, they need to coordinate their actions to carry out the task efficiently and to avoid interferences between individual robots. This is especially the case when considering the problem of exploring an unknown environment with a team of mobile robots. To achieve efficient terrain coverage with the sensors of the robots, one first needs to identify unknown areas in the environment. Second, one has to assign target locations to the individual robots so that they gather new and relevant information about the environment with their sensors. This assignment should lead to a distribution of the robots over the environment in a way that they avoid redundant work and do not interfere with each other by, for example, blocking their paths. In this paper, we address the problem of efficiently coordinating a large team of mobile robots. To better distribute the robots over the environment and to avoid redundant work, we take into account the type of place a potential target is located in (e.g., a corridor or a room). This knowledge allows us to improve the distribution of robots over the environment compared to approaches lacking this capability. To autonomously determine the type of a place, we apply a classifier learned using the AdaBoost algorithm. The resulting classifier takes laser range data as input and is able to classify the current location with high accuracy. We additionally use a hidden Markov model to consider the spatial dependencies between nearby locations. Our approach to incorporate the information about the type of places in the assignment process has been implemented and tested in different environments. The experiments illustrate that our system effectively distributes the robots over the environment and allows them to accomplish their mission faster compared to approaches that ignore the place labels.     

RANGE–Robust autonomous navigation in GPS‐denied environments

This paper addresses the problem of autonomous navigation of a micro air vehicle (MAV) in GPS‐denied environments. We present experimental validation and analysis for our system that enables a quadrotor helicopter, equipped with a laser range finder sensor, to autonomously explore and map unstructured and unknown environments. The key challenge for enabling GPS‐denied flight of a MAV is that the system must be able to estimate its position and velocity by sensing unknown environmental structure with sufficient accuracy and low enough latency to stably control the vehicle. Our solution overcomes this challenge in the face of MAV payload limitations imposed on sensing, computational, and communication resources. We first analyze the requirements to achieve fully autonomous quadrotor helicopter flight in GPS‐denied areas, highlighting the differences between ground and air robots that make it difficult to use algorithms developed for ground robots. We report on experiments that validate our solutions to key challenges, namely a multilevel sensing and control hierarchy that incorporates a high‐speed laser scan‐matching algorithm, data fusion filter, high‐level simultaneous localization and mapping, and a goal‐directed exploration module. These experiments illustrate the quadrotor helicopter's ability to accurately and autonomously navigate in a number of large‐scale unknown environments, both indoors and in the urban canyon. The system was further validated in the field by our winning entry in the 2009 International Aerial Robotics Competition, which required the quadrotor to autonomously enter a hazardous unknown environment through a window, explore the indoor structure without GPS, and search for a visual target. © 2011 Wiley Periodicals, Inc.     

Progress of Chinese Coastal Wetland based on Remote Sensing

Coastal wetlands as a unique ecosystems with high productivity and abundant biology diversity,has many important resource values,ecological values,economic values and scientific research values.Due to the multi\|temporal,multi\|platform,macroscopic,objective,informative,real\|time,highly effective,comparable and so on,so the remote sensing technology has been gradually approved and widely promoted in coastal wetland research in the past three decades.Current status of coastal wetland research based on remote sensing technique in China was systematically discussed from multiple aspects,including remote sensing data sources,theories and methods,and the application of remote sensing technology to Chinese coastal wetland is reviewed from the aspects of coastal wetland resource investigation and management,landscape pattern and dynamic change,ecological environment monitoring,ecosystem quality and service evaluation.This paper also points out some shortcomings existed in Chinese coastal wetland research by remote sensing technology include the spatial and temporal distributions of the study area is uneven and dominated by small and medium scale,lack of interdisciplinary comprehensive research,focus on theoretical research and ignore application intelligent application of remote sensing technology,information sharing ability is poor,the improve of interpretation accuracy is difficulties.Related research prospects should be to carry out such as monitoring and mapping on all scale,strengthen the multidisciplinary collaboration,strengthen the comprehensive and comparative study,establish a unified classification system of coastal wetland based on remote sensing and the national coastal wetland information system,emphasis on the development of new remote sensing technology and fusion of multi\|source data,emphasis on the use of new methods and new models.