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平流层飞艇是可靠性要求很高的系统,需要由具有容错能力的艇载计算机来进行控制和管理。针对艇载计算机采用的余度结构进行了软件管理策略的研究和设计,提出了基于异构总线的握手机制节点故障检测方法、基于“看门狗”与“心跳”相结合的 CPU 故障检测方法、基于节点健康矩阵的互援式总线重构方法及基于有限状态机的多 CPU 并行处理系统自适应重构方法。故障注入试验表明,艇载计算机在遇到故障时能实时检测出故障,诊断故障类型,并对故障进行处理,实现系统重构,保证了平流层飞艇长期驻空时的安全飞行。 相似文献
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《中国航空学报》2016,(3):738-745
Recently,stratospheric airships prefer to employ a vectored tail rotor or differential main propellers for the yaw control,rather than the control surfaces like common low-altitude airship.The load capacity of vectored mechanism and propellers are always limited by the weight and strength,which bring challenges for the attitude controller.In this paper,the yaw channel of airship dynamics is firstly rewritten as a simplified two-order dynamics equation and the dynamic characteristics is analyzed with a phase plane method.Analysis shows that when ignoring damping,the yaw control channel is available to the minimum principle of Pontryagin for optimal control,which can obtain a Bang–Bang controller.But under this controller,the control output could be bouncing around the theoretical switch curve due to the presence of disturbance and damping,which makes adverse effects for the servo structure.Considering the structure requirements of actuators,a phase plane method controller is employed,with a dead zone surrounded by several phase switch curve.Thus,the controller outputs are limited to finite values.Finally,through the numerical simulation and actual flight experiment,the method is proved to be effective. 相似文献
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本文简述了当今航空飞行器的发展概貌;回顾并剖析了空气动力学在航空飞行器发展过程中的重要作用;最后,对今后的发展前景作了展望。 相似文献
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《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2020,65(8):2062-2071
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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全数字仿真在临近空间飞艇研制过程中起着重作用。本文以临近空间飞艇为研究目标,首先分析飞艇的受力情况,将体积中心作为艇体坐标系原点建立飞艇动力学方程和运动学方程。综合起飞、降落和巡航中的风场特点,建立可变的风场模型。利用Matlab/simulink软件搭建仿真模型,实现飞艇全数字仿真。最后对仿真结果进行了简分析。 相似文献
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