Design of an aircraft autonomous traction taxiing system based on hydraulic secondary control

At present,aircraft taxiing at ground airports needs to be provided with a thrust by the main engine.The taxiing process is inefficient,has high fuel consumption and serious pollution,and is prone to safety risks.In this paper,a new configuration of aircraft autonomous traction taxiing system is proposed based on the principle of hydraulic secondary control,in which a hydraulic motor drive device is installed at the front wheels of the aircraft to drive the wheels to rotate forward or backward.Based on this,autonomous taxiing can be realized without relying on the main engines,thus greatly improving airport operation efficiency.Meanwhile,this paper analyzes the influencing factors of the autonomous traction taxiing process,and investigates the parameter matching design of the new configuration system.Besides,this paper develops the ground principle prototype,designs the aircraft longitudinal bonding force observer and the aircraft wheel disturbance moment observer,and proposes the speed control method of the aircraft front wheel autonomous traction taxiing by considering the ground bonding force saturation characteristics.Finally,the ground taxiing test is conducted,and the results show that the new configuration proposed in this paper presents a new solution for aircraft autonomous traction taxiing.

不同目标下城市出租车最优实载率模型

为确定合理的出租车实载率标准,以出租车价格、等候时间、空车里程为参数,构建了柯布-道格拉斯形式的出租车需求函数,并以此为基础构建出租车实载率确定模型,分别计算以社会福利最大化、生产者剩余为0、特定生产者剩余为目标的出租车最优实载率。计算结果表明:社会福利最大化时最优实载率取决于出租车价格、等候时间、空载里程的需求弹性,而生产者剩余为0时的最优实载率为平均单位里程成本与平均单位里程收入的比值。模型应用于北京市出租车市场,测算社会福利最大化、生产剩余为0、生产者剩余为15%目标下的最优实载率分别为60%、63%及74%。应用结果表明,模型能有效地区分不同目标下的出租车实载率标准,为行业管理者提供管理决策依据。