针对固定翼飞行器在可达区域内最佳应急着陆场选择问题,通过构建普适性的指标体系,将上述问题转化为多属性评价问题,并提出一种熵权灰色理想解逼近(technique for order preference by similarity to an ideal solution, TOPSIS)法对问...针对固定翼飞行器在可达区域内最佳应急着陆场选择问题,通过构建普适性的指标体系,将上述问题转化为多属性评价问题,并提出一种熵权灰色理想解逼近(technique for order preference by similarity to an ideal solution, TOPSIS)法对问题加以解决。从天气情况、着陆场特性、空域拥堵程度和地面保障能力4个方面进行分析,细化为13个评价指标,构建了应急着陆场评价指标体系。在传统TOPSIS的基础上,分别使用熵权法和灰色关联度对权重计算和距离测度进行改进,解决了传统方法依赖评价专家的主观赋权和采用欧式距离导致的无法评判优劣的问题。通过仿真对比,体现了所提方法在权重确定方面的客观性和距离测度方面的准确性,能够为飞行器应急着陆场的选择提供依据。展开更多
Shimmy can reduce the service life of the nose landing gear, affect ride comfort, and even cause fuselage damage leading to aircraft crashes. Taking a light aircraft as the research object, the torsional freedom of la...Shimmy can reduce the service life of the nose landing gear, affect ride comfort, and even cause fuselage damage leading to aircraft crashes. Taking a light aircraft as the research object, the torsional freedom of landing gear around strut axis and lateral deformation of tire are considered. Since the landing gear shimmy is a nonlinear system, a nonlinear mechanical model of the front landing gear shimmy is established. Sobol index method is proposed to analyze the influence of structural parameters on the stability region of the nose landing gear, and Routh-Huritz criterion is used to verify the reliability of the analysis results of Sobol index method. We analyse the effect of torsional stiffness of strut, caster length, rated initial tire inflation pressure, rake angle, and vertical force on the stability region of theront landing gear. And the research shows that the optimization of the torsional stiffness of the strut and the caster length of the nose landing gear should be emphasized, and the influence of vertical force on the stability region of the nose landing gear should be paid attention to.展开更多
文摘针对固定翼飞行器在可达区域内最佳应急着陆场选择问题,通过构建普适性的指标体系,将上述问题转化为多属性评价问题,并提出一种熵权灰色理想解逼近(technique for order preference by similarity to an ideal solution, TOPSIS)法对问题加以解决。从天气情况、着陆场特性、空域拥堵程度和地面保障能力4个方面进行分析,细化为13个评价指标,构建了应急着陆场评价指标体系。在传统TOPSIS的基础上,分别使用熵权法和灰色关联度对权重计算和距离测度进行改进,解决了传统方法依赖评价专家的主观赋权和采用欧式距离导致的无法评判优劣的问题。通过仿真对比,体现了所提方法在权重确定方面的客观性和距离测度方面的准确性,能够为飞行器应急着陆场的选择提供依据。
文摘Shimmy can reduce the service life of the nose landing gear, affect ride comfort, and even cause fuselage damage leading to aircraft crashes. Taking a light aircraft as the research object, the torsional freedom of landing gear around strut axis and lateral deformation of tire are considered. Since the landing gear shimmy is a nonlinear system, a nonlinear mechanical model of the front landing gear shimmy is established. Sobol index method is proposed to analyze the influence of structural parameters on the stability region of the nose landing gear, and Routh-Huritz criterion is used to verify the reliability of the analysis results of Sobol index method. We analyse the effect of torsional stiffness of strut, caster length, rated initial tire inflation pressure, rake angle, and vertical force on the stability region of theront landing gear. And the research shows that the optimization of the torsional stiffness of the strut and the caster length of the nose landing gear should be emphasized, and the influence of vertical force on the stability region of the nose landing gear should be paid attention to.
