无人机航拍在电视节目制作中的应用

阐述无人机航拍在电视节目制作中的技术要点,以及新闻、综艺、纪录片中的应用,特别是VR无人机航拍的技术特点及应用。     

无人机航测在山区水利测绘中的必要要素

无人机航测遥感是继卫星遥感、大飞机遥感之后发展起来的一项新型航空遥感技术,在应急测绘保障、国土资源监测、重大工程建设等方面得到广泛应用.无人机航测技术作为一项空间数据获取的重要手段,具有适用地形广泛、影像实时传输、高危地区探测、成本低、快速高效、使用机动灵活等优势.本文分析了山区测绘的基本自然地理情况,介绍了无人机技术国内外的发展情况以及无人机技术的特点和优势.分别从适合山区水利测绘的无人机机型、获取影像的遥感传感器、数据处理三个方面讨论山区无人机测绘的必要要素.     

转子流量计示值误差测量不确定度的评定

文章通过实例对转子流量计的示值误差不确定度进行了分析和评定.     

螺杆截面形状的数值拟合方法研究

研究了曲线拟合方法的特点,讨论了三次样条曲线和参数三次样条曲线的拟合方法在螺杆截面廓形拟合中的应用,给出了拟合的方程,并用实例验证了拟合的效果.同时解决了拟合过程中的单调性、失真、端点切向量的确定方法等一些关键技术问题.该方法为精确地生成刀具轨迹提供了光滑的型线方程.     

Dynamic modeling and nonlinear control strategy for an underactuated quad rotor rotorcraft

In this paper, a nonlinear dynamic MIMO model of a 6-DOF underactuated quad rotor rotorcraft is derived based on Newton-Euler formalism. The derivation comprises determining equations of motion of the quad rotor in three dimensions and seeking to approximate the actuation forces through modeling of the aerodynamic coefficients and electric motor dynamics. The derived model is dynamically unstable, so a sequential nonlinear control strategy is implemented for the quad rotor. The control strategy includes exact feedback linearization technique, using the geometric methods of nonlinear control. The performance of the nonlinear control algorithm is evaluated using simulation and the results show the effectiveness of the proposed control strategy for the quad rotor rotorcraft near quasi-stationary flight.     

铝合金熔体在线净化系统关键技术创新及应用

通过对引进的铝合金熔体在线净化系统主要参数的研究,优化与改进了净化系统的结构设计,包括反应器、氩气控制系统和石墨转子等核心部件,实现了铝合金熔体在线净化装备的升级创新,其除气除杂效果显著,分别超过40%和85%,铝合金熔体纯净度达到高等级。     

Nonlinear Analysis of Shape Memory Alloy Component in Rotor System

The active control of rotor vibration was studied while shape memory alloy (SMA) spring component was chosen as bearing of rotor system. The vibration of rotor system was controlled by the phase transformation of SMA with electric heating method. The SMA spring component has nonlinear coupling problem of thermal stress and thermal elasticity, because thermal constants α,β and elasticity constants γ, G vary with temperature when temperature changes sharply. Because δ,ε were both small parameters, their square items could be ignored and approximate results were obtained by perturbation. The characters of α,β, γ, G changing with temperature were analyzed. Results show that the character of thermal diffusivity ot changes with temperature, which cannot influence U,Ψ,So the nonlinearity of ot can be ignored; the character of,β changes with temperature,which cannot influence U, but influences Ψ at high temperature; the character of γ, G change with temperature, which cannot influence Ψ, but influences U with U^(01) ε. The more γ ,G, the more their influence on U;the nonlinearity of βT/pcvεkk influences U and Ψ, which must be calculated.     

无人机农田服务信息管理系统设计与实现

无人机在农业领域应用日益普及,但无人机供需信息服务水平还比较落后,为此设计了无人机农田服务信息系统。基于 Spring Boot 框架开发实现了一个 Web 应用程序,包括登录模块、订单模块、消息模块以及认证等功能模块。经测试,该系统具有较好的实用性。     

森林火灾应急通信保障方案研究与设计

森林火灾与城市火灾不同,其扑救方法也不完全相同。传统森林火灾扑救方法无法应对火灾环境恶劣、蔓延迅速快、点多线长面广的特点。针对该问题,结合城市消防救援队伍职能任务与典型森林火灾案例,提出一种加强森林火灾扑救应急通信保障能力的方法。通过构建卫星—无人机—地面的空天地一体化通信系统,保证话音、定位、图像等通信业务实时性,并设计一种基于倾斜摄影与金字塔匹配技术构建三维实景模型,提高后续灭火力量部署位置准确性。该方案有效性在广东佛山 12·5 山火消防救援扑救行动中得到了验证。     

基于虚拟仪器的转子动平衡实验

为了培养大学生实践能力,开发了基于虚拟仪器的转子动平衡实验。该文详细介绍了实验平台的构成、转子单面现场动平衡的三点加重法、可视化虚拟仪器软面板的构建、实验数据流程及实验实施过程。该实验使学生对旋转机械不平衡量的测量有了深刻认识。