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1.
对基于FPGA+DSP架构的图像压缩系统进行了介绍,描述了其系统结构、原理及实现。根据实际需求,采用FPGA+DSP的系统架构设计了一种高性能的图像实时压缩装置,并对系统硬件电路、软件、结构等方面进行了优化设计,实现了飞行试验环境条件下多路视频的采集、压缩、传输、按时序切换等功能,具有处理延时小、功耗低、环境适应性好等特点,并通过了高低温、振动冲击、电磁兼容等多项环境试验考核,具有较高的应用价值。  相似文献   

2.
为了解决金属环境条件下的无线供电和信号传输需求,提出了一种基于电容耦合方式的无线能量和信号并行传输方案。通过建立E类放大器的数学模型,分析电容耦合系统的传输特性和阻抗影响机理,设计了适用于E类放大器结构的调制与解调电路,并通过仿真验证了电路的可行性,为CCPT系统从能量传输到信号回传提供了系统性的理论指导。  相似文献   

3.
对基于FPGA+DSP架构的图像压缩系统进行了介绍,描述了其系统结构、原理及实现。根据实际需求,采用FPGA+DSP的系统架构设计了一种高性能的图像实时压缩装置,并对系统硬件电路、软件、结构等方面进行了优化设计,实现了飞行试验环境条件下多路视频的采集、压缩、传输、按时序切换等功能,具有处理延时小、功耗低、环境适应性好等特点,并通过了高低温、振动冲击、电磁兼容等多项环境试验考核,具有较高的应用价值。  相似文献   

4.
针对含有模型不确定性的章动非合作目标接触消旋问题,提出一种基于特征模型的双通道自适应控制方法。利用接触碰撞时的几何关系和线弹性接触力模型建立消旋系统动力学模型;分析目标自由运动特性,设计分离式消旋策略;构建描述章动目标消旋系统三轴角速度特性的特征模型,计算特征参数表达式;设计基于特征模型的双通道自适应控制器。仿真实验结果表明:所提方法通过在线估计特征参数,有效克服了消旋系统不确定性因素的影响,消旋后剩余角速度小且消旋速度快。  相似文献   

5.
平流层飞艇的热力学分析是平流层飞艇关键技术之一。针对热力学分析的工程验证及模型完善,提出了适合于平流层飞艇的艇囊内气体及囊体表面的温度测量方法,包括采集点的分布,传感器的选型,数据传输和处理及数据准确性评价等。经过两次平流层飞艇的缩比飞行试验,对比同艇发放的探空仪采集的温度数据,验证了该方法测量到的数据的准确性。  相似文献   

6.
为了研制国产示波器校准仪,简化模拟电路板设计,实现上位机对模拟电路的控制,设计基于现场可编程门阵列+单片机的示波器校准仪通信命令传输系统。在单片机中实现读写中断、串并转换模块,在FPGA中生成模拟电路芯片需要的所有直流、方波、正弦波的控制信号,利用上位机软件通过RS232串口对系统进行控制并显示结果,采用该架构数字处理系统的示波器校准仪可以输出满足技术指标要求的直流信号、方波信号、正弦波信号、时基信号、快沿脉冲信号,并具有阻抗测量功能。  相似文献   

7.
针对航天领域空间交会对接、航天器配电、在轨服务与维护等领域对无缆化的需求,提出了多通道近场无线能量传输系统,建立了多通道磁耦合近场无线能量传输系统数学模型,分析了影响系统传输效率的重要参数,并对关键参数对系统效率的影响进行了仿真分析。通过线圈高效耦合设计,实现了多通道近场无线能量传输系统的效率最优。所提系统解决了能量的无线传输,并实现多负载接收的问题。通过一台1 000 W多通道近场无线能量传输样机进行了实验研究,结果表明,所提多通道近场无线能量传输装置具有传输效率高的特点,解决了航天器无线能量传输的多负载问题。   相似文献   

8.
为研究基于深度强化学习的平流层浮空器高度控制问题。建立平流层浮空器动力学模型,提出一种基于深度Q网络(DQN)算法的平流层浮空器高度控制方法,以平流层浮空器当前速度、位置、高度差作为智能体的观察状态,副气囊鼓风机开合时间作为智能体的输出动作,平流层浮空器非线性动力学模型与扰动风场作为智能体的学习环境。所提方法将平流层浮空器的高度控制问题转换为未知转移概率下连续状态、连续动作的强化学习过程,兼顾随机风场扰动与速度变化约束,实现稳定的变高度控制。仿真结果表明:考虑风场环境对浮空器影响下,DQN算法控制器可以很好的实现变高度的跟踪控制,最大稳态误差约为10 m,与传统比例积分微分(PID)控制器对比,其控制效果和鲁棒性更优。  相似文献   

9.
基于PLL的往复摆动控制方法具有实现电路简单、可靠性高等优点,广泛应用于星载光机扫描型遥感器系统中。然而由于PLL鉴相单元和附加片簧的作用使扫描控制系统呈现复杂的非线性切换特性,难于进行控制回路的分析与设计。文章针对某星载光学遥感器PLL摆动扫描控制系统,详细分析了系统中存在的各种非线性特性,并应用小偏差线性化方法,建立了可供分析与设计的线性化模型,简化了扫描锁相回路设计的难度,在此基础上给出了锁相回路增益的设计准则,并通过仿真验证了模型分析结果的有效性,从而为此类基于PLL的摆动扫描控制系统奠定了理论分析基础和控制器设计依据。  相似文献   

10.
以模糊信息优化处理的观点,研究了信息扩散方式实现非参数输入的途径、方法和效果、本文用正态扩散方式处理知识样本,形成参数概率颁上模式,通过SIMAN仿真语言,对某一高速公路的一部分收费系统进行了仿真研究,结果表明:当人们对系统掌握的资料不多时,新方法有较大的优越性;如有较多的资料,新方法的结果与传统方法一致。  相似文献   

11.
Stratospheric airship is a new kind of aerospace system which has attracted worldwide developing interests for its broad application prospects. Based on the trajectory linearization control (TLC) theory, a novel trajectory tracking control method for an underactuated stratospheric airship is presented in this paper. Firstly, the TLC theory is described sketchily, and the dynamic model of the stratospheric airship is introduced with kinematics and dynamics equations. Then, the trajectory tracking control strategy is deduced in detail. The designed control system possesses a cascaded structure which consists of desired attitude calculation, position control loop and attitude control loop. Two sub-loops are designed for the position and attitude control loops, respectively, including the kinematics control loop and dynamics control loop. Stability analysis shows that the controlled closed-loop system is exponentially stable. Finally, simulation results for the stratospheric airship to track typical trajectories are illustrated to verify effectiveness of the proposed approach.  相似文献   

12.
平流层飞艇是一种新型的长航时临近空间飞行器,具有驻空高度高、驻空时间长、承载能力大、使用效费比高等特点,在对地观测及通信中继等领域具有广泛应用前景。但是该飞行器系统十分复杂,技术与设计实现难度大,总体设计需要考虑的基础问题及解决方案尚不完全明晰。根据平流层大气风场、温度和压力的基础特征,考虑平流层环境对平流层飞艇总体设计的影响,根据空气动力学与热力学基本理论,分析平流层飞艇的显著特征及与常规低空飞艇的区别,研究这些基础问题对平流层飞艇总体设计的影响,为平流层飞艇技术发展提供建议和参考。   相似文献   

13.
平流层飞艇太阳能源系统研究   总被引:3,自引:0,他引:3  
以平流层太阳能飞艇平台为背景,对平流层太阳能飞艇能源系统展开了分析和研究。文中建立了飞艇表面太阳能电池接收太阳直接辐射、散射辐射、反射辐射的模型。利用该模型对某飞艇太阳能电池进行计算,结果显示飞艇接收的太阳辐射能量与飞艇的工作纬度、季节、太阳能电池阵列表面面积、飞行姿态密切相关。当飞艇的脊背从日出到日落时刻正对太阳光线时,太阳能电池接收到的太阳辐射能量将是最大的。  相似文献   

14.
对一类气囊内外压差恒定的平流层软式飞艇,在考虑大气密度、温度变化以及大气风场的基础上,建立了飞艇三维空间运动的动力学模型;并针对能量消耗最少和航行时间最短两个指标函数,利用高斯伪谱法设计了飞艇从平流层返回地面的航迹,并对飞艇飞行高度、速度以及推力等状态变化进行分析研究.  相似文献   

15.
准确掌握储能电池的实际电量是确保平流层飞艇实现长航时飞行的关键因素之一。首先,建立了平流层飞艇能源系统仿真模型,对能量输入和消耗进行动态分析。随后,对储能电池进行不同电流倍率的充放电测试,采用多项式拟合的方法,根据测试数据建立了储能电池充放电过程中荷电状态(SOC)、剩余放电时间(RDT)、剩余充电时间(RCT)的分析模型。最后,结合能源系统能量输入、消耗模型和储能电池模型进行飞行模拟仿真,获取各部分变化数据,与已有试验数据进行量化对比分析。结果表明:所构建储能电池模型在SOC、RDT、RCT的计算误差分别小于3%、1.5%、1.5%,能够准确反映电池工作过程中SOC、RDT、RCT的变化,可为平流层飞艇平台制定优化的飞行策略提供量化支撑。   相似文献   

16.
This paper presents a novel approach for station-keeping control of a stratospheric airship platform in the presence of parametric uncertainty and external disturbance. First, conceptual design of the stratospheric airship platform is introduced, including the target mission, configuration, energy sources, propeller and payload. Second, the dynamics model of the airship platform is presented, and the mathematical model of its horizontal motion is derived. Third, a fuzzy adaptive backstepping control approach is proposed to develop the station-keeping control system for the simplified horizontal motion. The backstepping controller is designed assuming that the airship model is accurately known, and a fuzzy adaptive algorithm is used to approximate the uncertainty of the airship model. The stability of the closed-loop control system is proven via the Lyapunov theorem. Finally, simulation results illustrate the effectiveness and robustness of the proposed control approach.  相似文献   

17.
Ascent trajectory optimization with thermal effects is addressed for a stratospheric airship. Basic thermal characteristics of the stratospheric airship are introduced. Besides, the airship’s equations of motion are constructed by including the factors about aerodynamic force, added mass and wind profiles which are developed based on horizontal-wind model. For both minimum-time and minimum-energy flights during ascent, the trajectory optimization problem is described with the path and terminal constraints in different scenarios and then, is converted into a parameter optimization problem by a direct collocation method. Sparse Nonlinear OPTimizer(SNOPT) is employed as a nonlinear programming solver and two scenarios are adopted. The solutions obtained illustrate that the trajectories are greatly affected by the thermal behaviors which prolong the daytime minimum-time flights of about 20.8% compared with that of nighttime in scenario 1 and of about 10.5% in scenario 2. And there is the same trend for minimum-energy flights. For the energy consumption of minimum-time flights, 6% decrease is abstained in scenario 1 and 5% decrease in scenario 2. However, a few energy consumption reduction is achieved for minimum-energy flights. Solar radiation is the principal component and the natural wind also affects the thermal behaviors of stratospheric airship during ascent. The relationship between take-off time and performance of airship during ascent is discussed. it is found that the take-off time at dusk is best choice for stratospheric airship. And in addition, for saving energy, airship prefers to fly downwind.  相似文献   

18.
This paper reports a numerical investigation on the effects of water vapor condensing inside the air bag of a stratospheric airship on its ascending performance. The kinetic and thermal model considering vapor condensation was established, based on which a computer program was written in Fortran. The simulation results show that the vapor condensation remarkably affects the kinetic and thermal characteristics of the stratospheric airship in the ascent process. During the ascent process below 11 km, a large amount of latent heat is released when the water vapor in the air inside the air bag of the stratospheric airship condenses, which results in the increase of the temperature and the reduction of the weight of the air in the air bag, causing the airship to speed up, the accelerated expansion of the helium, and the decrease of the helium temperature in the helium bag. When the flight altitude is higher than 11 km, the effect of vapor condensation on the kinetic and thermal characteristics of the stratospheric airship is negligible because vapor is virtually nonexistent in the air.  相似文献   

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