Battery powered vertical takeoff and landing(VTOL) aircraft attracts more and more interests from public, while limited hover endurance hinders many prospective applications. Based on the weight models of battery, mot...Battery powered vertical takeoff and landing(VTOL) aircraft attracts more and more interests from public, while limited hover endurance hinders many prospective applications. Based on the weight models of battery, motor and electronic speed controller, the power consumption model of propeller and the constant power discharge model of battery, an efficient method to estimate the hover endurance of battery powered VTOL aircraft was presented. In order to understand the mechanism of performance improvement, the impacts of propulsion system parameters on hover endurance were analyzed by simulations, including the motor power density, the battery capacity, specific energy and Peukert coefficient. Ground experiment platform was established and validation experiments were carried out, the results of which showed a well agreement with the simulations. The estimation method and the analysis results could be used for optimization design and hover performance evaluation of battery powered VTOL aircraft.展开更多
针对城市场景下载人电动垂直起降飞行器(electric vertical takeoff and landing,eVTOL)路径规划问题进行了研究。首先,使用危险度栅格法进行三维城市空间建模,对选定型号的eVTOL飞行器,以航程、运行风险和高度变化为目标函数,结合飞行...针对城市场景下载人电动垂直起降飞行器(electric vertical takeoff and landing,eVTOL)路径规划问题进行了研究。首先,使用危险度栅格法进行三维城市空间建模,对选定型号的eVTOL飞行器,以航程、运行风险和高度变化为目标函数,结合飞行器自身特性及环境限制,构建了多约束条件的载人eVTOL路径规划模型。然后,设计了一种改进人工电场算法(im-proved artificial electric field algorithm,IAEFA),在传统人工电场算法(artificial electric field algorithm,AEFA)的基础上增加了自适应库伦参数,并在库伦常数的计算中引入递减系数,以此进行仿真求解。实验结果显示,所构建的模型可以达到预期效果。使用改进算法进行路径规划的求解效果更优,相较传统粒子群算法和人工电场法,航程更短,高度变化更小且运行更为安全。最后,根据对照实验确定递减系数的取值,当递减系数取值为1.5时,改进算法的求解效果最优。展开更多
针对城市内无人机起降场布局规划不合理的现象,首先利用最大覆盖模型进行选址求解,但因其需求点分布不均且需求覆盖判定标准过于单一,使得求解结果出现覆盖率不高、选址过于集中的情况。针对此问题,考虑需求在空间内的连续分布,结合无...针对城市内无人机起降场布局规划不合理的现象,首先利用最大覆盖模型进行选址求解,但因其需求点分布不均且需求覆盖判定标准过于单一,使得求解结果出现覆盖率不高、选址过于集中的情况。针对此问题,考虑需求在空间内的连续分布,结合无人机禁飞区、应用场景等限制因素,提出了一种基于空间连续需求的无人机起降场最大覆盖模型选址办法,利用规则网格确定需求对象、多边形交点集(polygon intersection point set, PIPS)方法确定起降场候选点。以天津市滨海新区城市内无人机起降场选址研究为例,验证了改进模型的可行性,在起降场建设数量均为14时,改进模型将实际服务面积覆盖率从62.03%提升至88.61%。其结果表明:该方法更符合无人机起降场选址的实际需求,使起降场选址布局均匀合理,能够显著提高无人机起降场服务覆盖率。展开更多
文摘Battery powered vertical takeoff and landing(VTOL) aircraft attracts more and more interests from public, while limited hover endurance hinders many prospective applications. Based on the weight models of battery, motor and electronic speed controller, the power consumption model of propeller and the constant power discharge model of battery, an efficient method to estimate the hover endurance of battery powered VTOL aircraft was presented. In order to understand the mechanism of performance improvement, the impacts of propulsion system parameters on hover endurance were analyzed by simulations, including the motor power density, the battery capacity, specific energy and Peukert coefficient. Ground experiment platform was established and validation experiments were carried out, the results of which showed a well agreement with the simulations. The estimation method and the analysis results could be used for optimization design and hover performance evaluation of battery powered VTOL aircraft.
文摘针对城市场景下载人电动垂直起降飞行器(electric vertical takeoff and landing,eVTOL)路径规划问题进行了研究。首先,使用危险度栅格法进行三维城市空间建模,对选定型号的eVTOL飞行器,以航程、运行风险和高度变化为目标函数,结合飞行器自身特性及环境限制,构建了多约束条件的载人eVTOL路径规划模型。然后,设计了一种改进人工电场算法(im-proved artificial electric field algorithm,IAEFA),在传统人工电场算法(artificial electric field algorithm,AEFA)的基础上增加了自适应库伦参数,并在库伦常数的计算中引入递减系数,以此进行仿真求解。实验结果显示,所构建的模型可以达到预期效果。使用改进算法进行路径规划的求解效果更优,相较传统粒子群算法和人工电场法,航程更短,高度变化更小且运行更为安全。最后,根据对照实验确定递减系数的取值,当递减系数取值为1.5时,改进算法的求解效果最优。
文摘针对城市内无人机起降场布局规划不合理的现象,首先利用最大覆盖模型进行选址求解,但因其需求点分布不均且需求覆盖判定标准过于单一,使得求解结果出现覆盖率不高、选址过于集中的情况。针对此问题,考虑需求在空间内的连续分布,结合无人机禁飞区、应用场景等限制因素,提出了一种基于空间连续需求的无人机起降场最大覆盖模型选址办法,利用规则网格确定需求对象、多边形交点集(polygon intersection point set, PIPS)方法确定起降场候选点。以天津市滨海新区城市内无人机起降场选址研究为例,验证了改进模型的可行性,在起降场建设数量均为14时,改进模型将实际服务面积覆盖率从62.03%提升至88.61%。其结果表明:该方法更符合无人机起降场选址的实际需求,使起降场选址布局均匀合理,能够显著提高无人机起降场服务覆盖率。
