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1.
各种原因导致盆栽植物因缺水而死亡的情况普遍存在。基于这个问题和实际需求,提出和设计了一种多节点网络化智能浇花机器人,实现了多盆栽的分布式浇花控制。该浇花机器人包含浇花机器人本体、盆栽网络化无线节点和无线网络模块,能够实现自动按照预定的路径行走,并对盆栽进行选择性浇花,提高了浇花机器人的效率;按照各盆栽的实际湿度进行无线测量和实时传输,提高了浇花的实时性。自动浇水保证了各盆栽的需求,定量和按需浇花能够节约水资源,实现无人化管理,起到环保和节能的作用,多节点的无线控制提高了浇花机器人的效率,减少了管道的布置,节约资源。  相似文献   

2.
针对混合无线传感器网络中的中继节点放置问题,提出了一种满足一定的连通性和生存性要求的最小数量中继节点放置算法,其中中继节点只能放置到候选位置的一个子集上。在连接中继节点的放置问题中,提出一种采用基于最小生成树的STP高效近似算法,以保证传感器节点和基站之间的连通性;在可生存中继节点的放置问题中,提出了基于{0,1,2}-SNDP的多项式时间近似算法,以保证传感器节点和基站之间的双连通性。实验结果表明,单层约束中继节点放置算法具有较小的运行时间和几乎可以达到与最优解结果相媲美的性能.  相似文献   

3.
基于无线通信和光通信的高压输电线路监测系统   总被引:5,自引:1,他引:4  
王炫  李红  丛琳 《电网技术》2009,33(18):198-203
提出一种高压输电线路监测系统方案,该系统由安装在输电线路铁塔上的无线监测节点、光通信节点以及电力特种光缆中的空闲纤芯组成。这些无线节点和光节点通过AdHoc组网方式构成具有自适应功能的基础通信网络,通过无线接力传输和光信号接力传输相结合的方式,实现监控中心与任意监测节点之间的双向信息交互。该系统可以对复杂地形条件下的长距离输电线路进行全程、逐塔的实时监测,还可以支持工作人员在输电线路延线的邻近区域内,利用专用无线终端接入监测网络,进行语音、数据、视频的双向通信,为线路检修和抢险救灾等特殊场合提供应急通信手段。  相似文献   

4.
与传统无线传输相比,虽然协作中继节点的参与可以大大提高无线网络性能,然而协作中继会带来严重的信道竞争问题,这给协作通信环境中的信道访问控制带来挑战。为了解决这个问题,提出一种RTS/CTS(Request To Send/Clear To Send)与忙音结合的MAC(media access control)信道接入方案。该方案使用3个忙音来标识信道的使用状态,并解决协作通信中的隐藏终端和暴露终端问题。基于忙音信号,还提出了一种带宽节俭的协作节点选择算法。通过侦听忙音信号,源节点可分布式地选择最优的协作节点。理论分析和仿真实验表明所提方案能有效地提高协作通信中的信道利用率,很好地解决了协作通信中的隐藏终端暴露终端问题。在数据包大小超过3 500 B时,本协议中暴露终端受传输节点阻塞的时间不到整个传输时间的10%。  相似文献   

5.
No paper has been published on the active use of the foot toe of biped walking robots. In other words, the sole of the supporting leg is usually assumed to completely contact the ground. To maintain this condition, the robot walking has a restriction such as the maximum walking speed limitation. If the point contact of the toe to the ground through walking is available, a variety of walking can be realized. In this paper, a new control method for biped robots, in which the contact of the sole to the ground becomes a point contact, is proposed. The COM (Center of Mass) and swing leg can track the desired path and each heel joint angle can be controlled by the proposed controller while a biped walking robot is following a forward falling. Therefore, the motion of the body does not need to be limited to quiet motion. The proposed method is verified by simulation and experimental results with “Ken,” a six‐joint DOF biped robot. © 2006 Wiley Periodicals, Inc. Electr Eng Jpn, 157(1): 72–79, 2006; Published online in Wiley InterScience ( http://www.interscience.wiley.com ). DOI 10.1002/eej.20094  相似文献   

6.
In this paper, a monitoring system for industrial robots working in factories is proposed. This system detects different movements based on learning and immediately reports to the operator. It has the advantage that there is no need to receive any signal from the robot controller because it only observes with a simple camera such as a CCD camera. For the detection method, the eigenspace method is used, which is excellent in compression of image data and calculations of the correlation among images. The parametric eigenspace method is also used to detect abnormalities such as the speed of movement. Some experiments using two‐axis robots show the effectiveness of the proposed method. © 2004 Wiley Periodicals, Inc. Electr Eng Jpn, 148(4): 74–83, 2004; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10352  相似文献   

7.
This paper proposes a control method based on a modal transformation for biped robots to climb unknown steps. The method is able to control the foot position of the biped robot and the ground reaction force acting in the vertical direction when the biped robot climbs unknown steps in a double support phase. The effectiveness of the proposed method is confirmed by the results of simulations and experiments. © 2012 Wiley Periodicals, Inc. Electr Eng Jpn, 181(3): 59‐69, 2012; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.21265  相似文献   

8.
In recent years, legged robots have progressed and are able to walk just like human beings. Hopping offers a possibility of moving faster and avoiding larger obstacles than walking. Thus, hopping becomes more significant. Copyright © 2004 Wiley Periodicals, Inc. In this paper, to take account of torque limits of motors, we propose the method of controlling the hopping height by changing the leg length at bottom. Considering an actual environment, the environment will change as the robot moves around. Therefore, we describe a way to estimate the actual thrust force. Using the estimated thrust force, command value of leg length in the landing phase is determined. The effectiveness of the proposed method is confirmed by simulation and experimental results. © 2006 Wiley Periodicals, Inc. Electr Eng Jpn, 155(1): 64–71, 2006; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20172  相似文献   

9.
This study proposes a variable dynamic threshold for a jerk signal for achieving contact detection in industrial robots. Sensorless force control is useful in applications in advanced industrial robots. The external torque of each joint is estimated accurately by using a disturbance observer and by inverse dynamics calculations. However, the phase lag of the disturbance observer and the dynamic parameter error create force estimation errors. These errors hamper quick and reliable contact detection in industrial robots. Therefore, this study proposes a useful approach to contact detection that uses a variable dynamic threshold for a jerk signal. The proposed variable dynamic threshold reduces contact detection failures caused by force estimation errors during the free motion of a robot. The proposed threshold is suitable for robot motion and improves the speed of contact detection. Numerical simulation results show that the proposed method is valid for the parameter variations in an actual industrial robot. In addition, experimental results show that the dynamic threshold is a useful technique for application to general robot systems as well. The dynamic threshold is useful in applications for any industrial sensorless force control system.  相似文献   

10.
群体机器人可依靠群智能有效分工协作完成复杂和大规模任务,在物流、制造、交通和军事等领域有极大的应用价值。然而,目前已有电能补给方式均无法满足其持续不间断充电的需求,导致强大的协同工作能力得不到充分发挥。为此,本文提出一种基于阵列式发射模组的群体机器人动态无线充电方式,可为群体机器人工作过程中实时供给电能。首先,分析了机器人动态无线充电过程中效率和功率的波动特性。其次,以充电效率最优为目标,提出一种带有惩罚机制改进的蚁群算法以及协同工作模式,并应用于群体机器人协同动态无线充电系统。最后,进行仿真实验,验证了本文提出的方法可实现群体机器人在动态无线充电过程中稳定可靠协同工作。本文的研究对群体智能的研究具有极大的促进作用。  相似文献   

11.
One of the most important events for hopping robots is lift‐off (the end of thrusting phase) since hopping motions often become unstable during the lift‐off. Therefore, we focus on the thrusting phase. In this research, we propose a new controller, which combines two controllers. We also propose a trajectory planning so that a hopping robot follows command value of the vertical velocity. The effectiveness of the proposed methods is confirmed by simulation and experiments. © 2009 Wiley Periodicals, Inc. Electr Eng Jpn, 169(2): 29–36, 2009; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20831  相似文献   

12.
针对巡逻机器人的避障导航,基于Realsense深度摄像头获取环境深度信息,在使用机载计算机对深度图像进行分层处理的基础上,设计了巡逻机器人避障导航系统,同时对巡逻机器人通信协议以及决策流程等进行了改进设计,最后在ROS机器人开源操作系统上对其进行实验及验证。实验结果表明,在相同环境下,该方法能使巡逻机器人快速、安全、有效地避开静态障碍物而到达目标点。该方法不仅能够提高避障的成功率,获得实时避障效果,而且能够降低巡逻机器人的数据处理量,有利于巡逻机器人的移植。  相似文献   

13.
为改善LoRaWAN网络架构中,终端节点移动造成信号错误传播以及高能耗问题,在混合译码放大转发(hybrid decode-amplify-and-orward, HDAF)方式下,给出一种基于LoRa网关的无线中继优化算法方案。该方案中,LoRa网关具备中继转发功能,基于节点间的位置关系,推导了HDAF方式下的误码率 (symbol-error-rate, SER)表达式。构造Lagrange函数,在SER约束的Karush-Kuhn-Tucker(KKT)极值条件下,给出最佳功率分配方案。数值分析表明:同等条件下,所给方案比AF、DF方式的误码率低。各节点消耗的功率比AF、DF方式低,节省了能耗。#$NL关键词:LoRa;混合译码放大转发;功率分配;中继选择;误码率#$NL中图分类号:TN929.5  相似文献   

14.
为了提高移动机器人在室内人机共融环境下的运动安全和交互性,提出了一种融合行人运动信息的室内移动机器人动 态避障方法,同时考虑任务约束和社会规则。 首先,利用 YOLO v3 算法和 Deep Sort 算法分别对室内环境中的行人进行实时检 测与目标跟踪,计算行人在过去时刻的历史轨迹。 然后,利用 Social-GAN 算法构建行人交互模型,实现轨迹预测。 在此基础上, 将行人的运动状态融合进机器人避障算法之中,根据社会规则设计评价函数,对机器人采样速度样本进行评估,使移动机器人 能够以安全和舒适的方式绕过行人,确保室内人机共融环境下移动机器人的社会接受性。 通过实验对比分析,与传统 DWA 方 法相比,本文方法不仅可以提高机器人导航避障效率,在相同室内场景下导航避障时间由 23. 56 s 提高到 19. 38 s,而且可以有 效降低与行人发生碰撞的风险,保证机器人导航的安全和社交性。  相似文献   

15.
为实现电缆通道通信网络缺失、故障或受攻击等应急情况下的环境信息监测需求,研发了一种基于WiFi和超宽带(ultra-wide band,UWB)通信的低成本移动无线传感网络监测系统。该系统包括监测上位机和由球形机器人移动节点组成的无线监测网络。移动节点以STM32系列单片机为主控芯片,集成摄像头模块和温湿度模块实现现场信息采集,集成WiFi通信模块采用无线自组网按需平面距离向量路由协议(ad hoc on-demand distance vector routing, AODV)构建无线传感网络实现信息传输,集成3个UWB通信模块实现移动节点的测距和队列跟随。实验结果表明,该系统能够实现电缆通道环境的稳定实时监测,移动传感队列跟随误差不超过20 cm,监测视频平均传输延时不超过150 ms。  相似文献   

16.
This paper reports an outdoor experiment to optimize the timeout of wireless network coding (WNC) and frame aggregation (FA), which are implemented to carrier sense multiple access with collision avoidance (CSMA/CA)‐based wireless two‐hop relay prototype. The system throughput is improved. In the prototype, FA is implemented at the terminal nodes. Timeout function for WNC is available at the relay node and that for FA is available at the terminal nodes. Our outdoor experiment shows that optimizing the timeout values of WNC and FA can improve system throughput by 2.04‐fold compared to the conventional relay without WNC or FA. © 2016 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.  相似文献   

17.
This paper addresses the output feedback tracking control problem of electrically driven wheeled mobile robots subjected to actuator constraints. The main drawback of previously proposed controllers is the actuator saturation problem, which degrades the transient performance of the closed‐loop control system. In order to alleviate this problem, a saturated tracking controller has been proposed using the hyperbolic tangent function. A new nonlinear observer is introduced in order to leave out the velocity sensors in the robot system to decrease the cost and weight of the system for practical applications. A dynamic surface control strategy is effectively used to reduce the design complexity when considering actuator dynamics. In addition, neural network approximation capabilities and adaptive robust techniques are also adopted to improve the tracking performance in the presence of uncertain nonlinearities and unknown parameters. Semi‐global stability of the closed‐loop system is presented using direct Lyapunov method. Simulation results are provided to illustrate the effectiveness of the proposed control system for a differential drive mobile robot in practice. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   

18.
为了在低发射功率的前提下扩展蜂窝小区的覆盖范围,本文基于多跳通信模式,提出由中心基站负责固定中继节点接入,移动节点通过固定中继节点的多跳中继而连接基站的网络结构,即接入式多跳小区结构.此结构提供了在低成本条件下完成区域覆盖的方法.对该小区结构的覆盖特性进行了分析,结果显示具有3个或4个固定中继节点的多跳小区结构可以有效地实现基站覆盖范围的扩展.  相似文献   

19.
This paper proposes a new method for generation of a position reference that has both vibration suppression performance and fast tracking performance for industrial robots. It is important for industrial robots to drive at high speed and with high accuracy. In such cases, vibration is generated. Conventionally, the notch filter is used in order to reduce vibration. It is able to eliminate the natural frequency component, but a reference phase error is generated. The reference phase error causes locus error in the robot. Therefore, the accuracy of the robot is degraded by using a notch filter. The proposed method overcomes this problem by using the compensation gain. The proposed compensation gain is used in order to calculate the reference phase error. Compensation of the reference phase error is attained by feedforward input. Numerical and the experimental results confirm that the proposed method is valid for reducing vibration phenomena and that it decreases the phase error. © 2011 Wiley Periodicals, Inc. Electr Eng Jpn, 175(1): 53–63, 2011; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.20931  相似文献   

20.
介绍了一种线路巡检机器人伺服控制系统。控制系统包括了对超声波电机、永磁直流齿轮减速电机等多个电机的协调控制,完成了对高压线路上故障的发现、清除、回收。控制系统以RS232作为主要通信方式,以无线通信作为主要通信途径,保证了机器人在高压线路工作中的可靠性。控制系统通过对机器人工作状态量的采集,保证了机器人能够在规定电量内完成规定的工作量,提高了线路巡检工作的效率。  相似文献   

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