Wireless Sensor Network(WSN)is a cornerstone of Internet of Things(IoT)and has rich application scenarios.In this work,we consider a heterogeneous WSN whose sensor nodes have a diversity in their Residual Energy(RE).I...Wireless Sensor Network(WSN)is a cornerstone of Internet of Things(IoT)and has rich application scenarios.In this work,we consider a heterogeneous WSN whose sensor nodes have a diversity in their Residual Energy(RE).In this work,to protect the sensor nodes with low RE,we investigate dynamic working modes for sensor nodes which are determined by their RE and an introduced energy threshold.Besides,we employ an Unmanned Aerial Vehicle(UAV)to collect the stored data from the heterogeneous WSN.We aim to jointly optimize the cluster head selection,energy threshold and sensor nodes’working mode to minimize the weighted sum of energy con-sumption from the WSN and UAV,subject to the data collection rate constraint.To this end,we propose an efficient search method to search for an optimal energy threshold,and develop a penalty-based successive convex approximation algorithm to select the cluster heads.Then we present a low-complexity iterative approach to solve the joint optimization problem and discuss the implementation procedure.Numerical results justify that our proposed approach is able to reduce the energy consumption of the sensor nodes with low RE significantly and also saves energy for the whole WSN.展开更多
针对物流仓储中危险品搬运的特殊需求,根据实用功能需求和以往搬运机器人的性能要求,设计了一种码垛机器人。介绍了机器人的总体及其重要部件的设计功能。通过布局草图设计零件模型,采用自上而下的建模方法,利用Solid works对三自由度...针对物流仓储中危险品搬运的特殊需求,根据实用功能需求和以往搬运机器人的性能要求,设计了一种码垛机器人。介绍了机器人的总体及其重要部件的设计功能。通过布局草图设计零件模型,采用自上而下的建模方法,利用Solid works对三自由度码垛机器人的基本结构及组成部件进行建模,利用Solid works simulation插件进行了装配干涉检查并对其关键部件的设计进行了分析,以确保关键部位可靠性和安全性。分析结果显示,该机器人在满负载情况下,车架的设计能够满足危险品物流自动化的需求,因而提供了一种实用型的码垛机器人的特殊设计。展开更多
介绍了基于Solid W orks特征造型的特点及分类,并从设计、工艺、加工的角度阐述了特征的定义。对如何提取Solid W orks零件特征的几何信息进行了研究,提出了三种特征提取方法。并以Solid W orks中的零件为例,通过VC++6.0语言设计程序,...介绍了基于Solid W orks特征造型的特点及分类,并从设计、工艺、加工的角度阐述了特征的定义。对如何提取Solid W orks零件特征的几何信息进行了研究,提出了三种特征提取方法。并以Solid W orks中的零件为例,通过VC++6.0语言设计程序,成功地提取了零件特征的几何信息,将之保存在数据库中,为CAPP/CAM系统对数据的利用做好了准备。展开更多
基金supported in part by the National Nature Science Foundation of China under Grant 62001168in part by the Foundation and Application Research Grant of Guangzhou under Grant 202102020515.
文摘Wireless Sensor Network(WSN)is a cornerstone of Internet of Things(IoT)and has rich application scenarios.In this work,we consider a heterogeneous WSN whose sensor nodes have a diversity in their Residual Energy(RE).In this work,to protect the sensor nodes with low RE,we investigate dynamic working modes for sensor nodes which are determined by their RE and an introduced energy threshold.Besides,we employ an Unmanned Aerial Vehicle(UAV)to collect the stored data from the heterogeneous WSN.We aim to jointly optimize the cluster head selection,energy threshold and sensor nodes’working mode to minimize the weighted sum of energy con-sumption from the WSN and UAV,subject to the data collection rate constraint.To this end,we propose an efficient search method to search for an optimal energy threshold,and develop a penalty-based successive convex approximation algorithm to select the cluster heads.Then we present a low-complexity iterative approach to solve the joint optimization problem and discuss the implementation procedure.Numerical results justify that our proposed approach is able to reduce the energy consumption of the sensor nodes with low RE significantly and also saves energy for the whole WSN.
文摘针对物流仓储中危险品搬运的特殊需求,根据实用功能需求和以往搬运机器人的性能要求,设计了一种码垛机器人。介绍了机器人的总体及其重要部件的设计功能。通过布局草图设计零件模型,采用自上而下的建模方法,利用Solid works对三自由度码垛机器人的基本结构及组成部件进行建模,利用Solid works simulation插件进行了装配干涉检查并对其关键部件的设计进行了分析,以确保关键部位可靠性和安全性。分析结果显示,该机器人在满负载情况下,车架的设计能够满足危险品物流自动化的需求,因而提供了一种实用型的码垛机器人的特殊设计。
文摘介绍了基于Solid W orks特征造型的特点及分类,并从设计、工艺、加工的角度阐述了特征的定义。对如何提取Solid W orks零件特征的几何信息进行了研究,提出了三种特征提取方法。并以Solid W orks中的零件为例,通过VC++6.0语言设计程序,成功地提取了零件特征的几何信息,将之保存在数据库中,为CAPP/CAM系统对数据的利用做好了准备。