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High-precision gyro-stabilized control of a gear-driven platform with a floating gear tension device

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Frontiers of Mechanical Engineering 2021年第3期16卷 487-503页

作者： xianliang jiang Dapeng FAN Shixun FAN Xin XIE Ning CHEN College of Intelligence Science and Technology National University of Defense TechnologyChangsha 410073China

This study presents an improved compound control algorithm that substantially enhances the antidisturbance performance of a gear-drive gyro-stabilized platform with a floating gear tension *** tension device can provide a self-adjustable preload to eliminate the gap in the meshing ***,the weaker gear support stiffness and more complex meshing friction are also induced by the tension device,which deteriorates the control accuracy and the ability to keep the aim point of the optical sensors isolated from the platform *** modeling and compensation of the induced complex nonlinearities are technically challenging,especially when base motion *** aim of this research is to cope with the unmeasured disturbances as well as the uncertainties caused by the base lateral ***,the structural properties of the gear transmission and the friction-generating mechanism are analyzed,which classify the disturbances into two categories:Time-invariant and time-varying ***,a proportional-integral controller is designed to eliminate the steady-state error caused by the time-invariant disturbance.A proportional multiple-integral-based state augmented Kalman filter is proposed to estimate and compensate for the time-varying disturbance that can be approximated as a polynomial *** effectiveness of the proposed compound algorithm is demonstrated by comparative experiments on a gear-drive pointing system with a floating gear tension device,which shows a maximum 76%improvement in stabilization precision.

关键词： inertially stabilized platform floating gear tension device nonlinear friction disturbance compensation proportional multiple-integral observer

Analysis and control of micro-stepping characteristics of ultrasonic motor

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Frontiers of Mechanical Engineering 2020年第4期15卷 585-599页

作者： Ning CHEN Jieji ZHENG xianliang jiang Shixun FAN Dapeng FAN College of Intelligence Science and Technology National University of Defence and TechnologyChangsha 410073China

Micro-stepping motion of ultrasonic motors satisfies biomedical applications, such as cell operation and nuclear magnetic resonance, which require a precise compact-structure non-magnetization positioning device. When the pulse number is relatively small, the stopping characteristics have a non-negligible effect on the entire stepwise process. However, few studies have been conducted to show the rule of the open-loop stepwise motion, especially the shutdown stage. In this study, the modal differences of the shutdown stage are found connected with amplitude and velocity at the turn-off instant. Changes of the length in the contact area and driving zone as well as the input currents, vibration states, output torque, and axial pressure are derived by a simulation model to further explore the rules. The speed curves and vibration results in functions of different pulse numbers are compared, and the stepwise motion can be described by a two-stage two-order transfer function. A test workbench based on the Field Programmable Gate Array is built for acquiring the speed, currents, and feedback voltages of the startup–shutdown stage accurately with the help of its excellent synchronization performances. Therefore, stator vibration, rotor velocity, and terminal displacements under different pulse numbers can be compared. Moreover, the two-stage two-order model is identified on the stepwise speed curves, and the fitness over 85% between the simulation and test verifies the model availability. Finally, with the optimization of the pulse number, the motor achieves 3.3 µrad in clockwise and counterclockwise direction.

关键词： ultrasonic motor stepping characteristics pulse number control synchronous acquisition system precise positioning

An Efficient Priority-Driven Congestion Control Algorithm for Data Center Networks

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China Communications 2020年第6期17卷 37-50页

作者： Jiahua Zhu xianliang jiang Yan Yu Guang Jin Haiming Chen Xiaohui Li Long Qu College of Information Science and Engineering Ningbo UniversityNingbo 315211China College of Cybersecurity Sichuan UniversityChengdu 610065China

With the emerging diverse applications in data centers,the demands on quality of service in data centers also become diverse,such as high throughput of elephant flows and low latency of deadline-sensitive ***,traditional TCPs are ill-suited to such situations and always result in the inefficiency(*** the flow deadline,inevitable throughput collapse)of data *** further degrades the user-perceived quality of service(QoS)in data *** reduce the flow completion time of mice and deadline-sensitive flows along with promoting the throughput of elephant flows,an efficient and deadline-aware priority-driven congestion control(PCC)protocol,which grants mice and deadline-sensitive flows the highest priority,is proposed in this ***,PCC computes the priority of different flows according to the size of transmitted data,the remaining data volume,and the flows’*** PCC adjusts the congestion window according to the flow priority and the degree of network ***,switches in data centers control the input/output of packets based on the flow priority and the queue *** from existing TCPs,to speed up the data transfers of mice and deadline-sensitive flows,PCC provides an effective method to compute and encode the flow priority *** to the flow priority,switches can manage packets efficiently and ensure the data transfers of high priority flows through a weighted priority scheduling with minor *** experimental results prove that PCC can improve the data transfer performance of mice and deadline-sensitive flows while guaranting the throughput of elephant flows.

关键词： data center network low-latency priority switch scheduling transmission control protocol

LEDBAT协议优先级反转抑制的启发式动态阈值算法

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计算机研究与发展 2020年第6期57卷 1292-1301页

作者：马阿曼江先亮金光宁波大学信息科学与工程学院浙江宁波315211

近年来,随着通信技术和网络传输能力的大幅度提升,应用需求呈现多元化的增长态势(视频会议、在线游戏等交互式应用要求低时延、低抖动,而软件更新等应用则要求高吞吐).为满足时延不敏感的数据传输并保证高效的瓶颈带宽利用率,低优先级... 详细信息

近年来,随着通信技术和网络传输能力的大幅度提升,应用需求呈现多元化的增长态势(视频会议、在线游戏等交互式应用要求低时延、低抖动,而软件更新等应用则要求高吞吐).为满足时延不敏感的数据传输并保证高效的瓶颈带宽利用率,低优先级拥塞控制算法(如LEDBAT(low extra delay background transport))受到广泛关注.该类算法能在链路空闲时占用未被使用的带宽,而在链路负载较高时释放占用的带宽以保证时延敏感数据的传输.然而,当中间路由器部署主动队列管理算法时,低优先级拥塞控制算法存在优先级反转问题,即链路高负载时无法释放占用的带宽,使其退化为普通拥塞控制算法.为解决该问题,针对LEDBAT中的固定时延阈值造成的优先级反转,提出启发式的动态阈值调整算法,其在运行时动态搜索最优的动态时延阈值,确保LEDBAT与主动队列管理算法共存时仍能保持低优先级特性,同时不降低链路的利用率.为验证算法的有效性,在网络模拟NS2中建立了不同网络场景并对算法进行大量的评估.实验结果表明:与已有低优先拥塞控制算法相比,新算法能够有效解决优先级反转的问题,同时保证链路的带宽利用率.

关键词：拥塞控制算法 LEDBAT算法主动队列管理优先级重置启发式动态阈值

基于卷积神经网络的玛钢管件表面缺陷检测仿真

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江苏大学学报（自然科学版） 2024年第4期45卷 449-455,463页

作者：白杰江先亮宁波大学信息科学与工程学院浙江宁波315211

针对现有检测算法HRNetV2p无法很好地平衡各尺度缺陷的检测精度等问题,在HRNetV2p中引入一种结合通道注意力机制的特征融合模块,自适应地调整融合特征中空间-语义信息的比率,解决浅层特征缺乏语义信息的问题.建立一个玛钢管件表面缺陷... 详细信息

针对现有检测算法HRNetV2p无法很好地平衡各尺度缺陷的检测精度等问题,在HRNetV2p中引入一种结合通道注意力机制的特征融合模块,自适应地调整融合特征中空间-语义信息的比率,解决浅层特征缺乏语义信息的问题.建立一个玛钢管件表面缺陷检测数据集IIDD,进行数据标注及数据统计.在HRNetV2p网络中引入CG密集跳跃传输单元及CG自适应融合模块,通过整合、重新校准和重新整合3个操作自适应地调整浅层特征空间-语义信息比率.给出了试验的设置以及评价指标,完成了改进的玛钢管件表面缺陷检测算法在IIDD测试集上的性能试验.结果表明,改进后的HRNetV2p算法在IIDD上的平均检测精度AP 50为91.3%,相比原始HRNetV2p提高了2.6%,其中对大、中、小尺度缺陷的平均检测精度分别提高了2.7%、2.7%、5.6%.

关键词：玛钢管件表面缺陷检测仿真卷积神经网络注意力机制 HRNetV2p 特征融合

基于无人船的水产养殖水质动态监测系统设计与实验

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农业机械学报 2020年第9期51卷 175-185,174页

作者：江先亮尚子宁金光宁波大学信息科学与工程学院宁波315211

针对传统水产养殖水质监测多使用部署在固定位置的无线监测节点,存在监测范围小、监测位置不灵活和部署成本偏高等问题,设计了基于自动无人船的水产养殖水质动态监测系统。该系统融合无人船和多个传感器进行水质采样,测量水温、pH值和... 详细信息

针对传统水产养殖水质监测多使用部署在固定位置的无线监测节点,存在监测范围小、监测位置不灵活和部署成本偏高等问题,设计了基于自动无人船的水产养殖水质动态监测系统。该系统融合无人船和多个传感器进行水质采样,测量水温、pH值和水体浊度等指标,通过岸基控制台将监测数据上传至云服务器。为保证系统的有效性和准确性,提出以自动无人船悬停采样为主的水质监测和低航速下的水质异常检测,结合基于地图解析的路径规划策略,实现无人船自主航行,以提升监测效率。经实验验证,与传统方案相比,动态监测得到的水温相对误差绝对值不大于0.5%,pH值相对误差绝对值不大于1.43%,浊度相对误差绝对值不大于4.9%,均在各传感器精度范围内,可满足监测需求。将该系统部署于水产养殖区,在9800 m^2水域内共采集731组有效数据,测得各水质指标数值均在正常范围内,监测区域覆盖达水域面积的68%。该方法为水产养殖业的水质监测和异常检测提供了解决方案。

关键词：水产养殖水质监测自动无人船导航

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面向海岛环境的海雾能见度监测系统应用研究

传感技术学报 2018年第8期31卷 1287-1294页

作者：张超金光江先亮宁波大学信息科学与工程学院浙江宁波315211

随着无线传感网技术的日益成熟,以及对海岛资源探索的需求,利用无线传感网监测海岛气象信息逐渐受到关注。本文设计实现了低成本的海雾能见度监测系统,可在海岛等崎岖地域组网工作。系统利用低成本传感器,实时采集温湿、风速等气象参数... 详细信息

随着无线传感网技术的日益成熟,以及对海岛资源探索的需求,利用无线传感网监测海岛气象信息逐渐受到关注。本文设计实现了低成本的海雾能见度监测系统,可在海岛等崎岖地域组网工作。系统利用低成本传感器,实时采集温湿、风速等气象参数,获取同一时刻、地点的能见度数值,通过Z-score归一化方法进行数据校准,并使用人工神经网络结合支持向量机的方法训练模型,以收集的监测数据作为输入,获得较高精度的能见度输出。大量实验表明该系统可在地域偏远、传统方法难以奏效的场景下,实现较高精度的能见度监测应用。

关键词：无线传感网海雾能见度海岛环境监测模型

基于低功耗广域网的海岛水产养殖环境监测系统研制

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农业工程学报 2018年第24期34卷 184-191页

作者：金光高子航江先亮朱家骅宁波大学信息科学与工程学院宁波315211

针对海岛环境中水产养殖区域分散、工作环境恶劣、人工巡检不便等问题,设计了基于低功耗广域物联网的海岛养殖环境监测系统。系统包括集成Arduino和传感器的终端采集节点,通过LoRa技术实现数据汇总和远距离传输的汇聚网关,利用Python与P... 详细信息

针对海岛环境中水产养殖区域分散、工作环境恶劣、人工巡检不便等问题,设计了基于低功耗广域物联网的海岛养殖环境监测系统。系统包括集成Arduino和传感器的终端采集节点,通过LoRa技术实现数据汇总和远距离传输的汇聚网关,利用Python与PostgreSQL开发用于数据接收、存储、处理、访问和控制的后台监测系统。通过对网络拓扑复杂度、能耗等方面的评估,表明在海岛环境下部署水产养殖环境监测系统,相比传统Zigbee多跳无线传感网,采用LoRaWAN,其单跳节点覆盖范围更大,而网络复杂度、能耗等更优。测试表明该系统能以较低功耗实现整片区域内远距离数据采集,有效传输养殖区水体环境数据。网络生存期与传输可靠性测试表明,当传感器节点采用3.7 V/4 200 mAh锂电池,上传周期为30 min时,监测网络的有效生存期理论上可达2.4 a;在800 m通信范围内,发射功率为20 mW时,节点丢包率小于3.6%,具有较高的通信可靠性。该研究可为水产养殖生产和物联网应用研究提供有效参考。

关键词：水产养殖环境监测无线传感网络低功耗广域网海岛环境监测系统

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人工气胸辅助下肺结节定位技术

中华胸心血管外科杂志 2023年第5期39卷 309-310页

作者：江贤亮储森林魏宁柯立中国科学技术大学附属第一医院安徽省立医院胸外科合肥230001 中国科学技术大学附属第一医院安徽省立医院介入科合肥230001

肺小结节是肺部常见疾病,也是胸外科的主要疾病之一。肺小结节术中查找困难,多数需术前定位。但是部分肺结节位置隐蔽,因脊柱或肩胛骨遮挡,找不到合适的进针路径,无法直接定位。本文介绍人工气胸辅助肺结节定位法,以解决该难题。

关键词：位置隐蔽肺小结节胸外科肺结节人工气胸定位法术前定位肩胛骨