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小型四旋翼无人机建模与有限时间控制
Modeling and finite-time control for quad-rotor mini unmanned aerial vehicles
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廖卫中,宗群,马亚丽
控制理论与应用 , 2015, DOI: 10.7641/CTA.2015.50419
Abstract: 本文首先介绍了一种小型四旋翼无人机的设计过程, 从机架设计、动力匹配、机载控制器、传感器、无线通 信等多个方面进行了较为详尽的阐述. 采用牛顿―欧拉法对四旋翼无人机进行动力学分析, 完成了六自由度数学 模型的推导. 进一步对系统的模型参数进行了测量和计算, 并给出了结果. 在此基础上, 为了满足无人机快速跟踪 性能的要求, 本文基于快速终端滑模的思想, 进行了闭环控制器的设计, 并给出了基于Lyapunov函数的稳定性证明. 控制器采用分环控制的结构形式, 内环为姿态控制, 外环为位置控制. 最后结合设计的四旋翼无人机, 给出的仿真结 果验证了控制算法的有效性.
We start by giving the detailed design process for a quad-rotor mini unmanned aerial vehicle, including the airframe design, propulsion system, autopilot, sensors and wireless communication. By using Newton-Euler’s laws, we analyze the dynamics of such an aerial vehicle to derive for it a 6-degrees mathematical model with parameter values measured and calculated. To meet the requirement on fast tracking performance, we develop a closed-loop control system based on the concept of fast terminal sliding-mode control, and prove its stability by using Lyapunov function. This control system is composed of two nested control loops: the inner loop for the attitude control and the outer loop for the position control. Simulation results show that the proposed method can provide robustness and good tracking performance for the designed quad-rotor mini unmanned aerial vehicle.
基于区间矩阵的四旋翼无人机鲁棒跟踪控制
Robust tracking control of a quad-rotor UAV via Interval matrix
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孙妙平,刘静静,年晓红,王海波
控制理论与应用 , 2017, DOI: 10.7641/CTA.2017.60559
Abstract: 针对飞行环境不断变化的四旋翼无人机轨迹跟踪问题, 提出了基于区间矩阵的鲁棒跟踪控制策略. 首先, 将四旋翼无人机非线性动态模型解耦为外环位置控制系统和内环角度控制系统. 接着, 考虑到飞行环境变化引起的升力系数、 中高速飞行下不可忽略的阻力系数等参数的不确定性, 引入区间矩阵对内外环系统的系统参数进行描述, 并对内外环控制系统设计鲁棒 H∞反馈控制策略来抑制有界外部扰动. 然后, 根据李雅普诺夫稳定性定理得到了使外环系统指数渐近稳定和内环系统鲁棒渐近稳定且均满足 H∞性能指标的LMI 充分条件,同时, 给出了控制器增益的求解方法. 最后, 仿真及实验结果结果验证了所提方法的鲁棒性,优越性和有效性.
In this paper,the robust tracking control strategies for a quad-rotor unmanned aerial vehicle (UAV) with changing flight environment are put forward based on the interval matrix. Firstly, the nonlinear dynamic model of the quad-rotor UAV is decoupled into the inner loop attitude control system and the outer loop position control system. Next, taking into account the change of the lift coefficient and non-negligible drag coefficient in medium and high speed which is caused by the changing flight environment, the interval matrix is introduced to describe the system parameters of the inter and outer loop system and the robust H∞ feedback control methods are designed to reject the bounded disturbance in the closed inner-outer loop system. Then, according to Lyapunov stability theory, the LMI-based sufficient conditions of exponential asymptotic stability for outer-loop control system and robust asymptotic stability for inter-loop control system are derived. At the same time, the H∞ performance indexes are both satisfied. Meanwhile, the gain matrices of controller are presented. Finally, the effectiveness, advantages and robustness of the proposed method are verified by simulation and experimental results.
Predictive Control of Quad-Rotor Delivering Unknown Time-Varying Payloads Based upon Extended State Observer  [PDF]
Yuan Wang
Advances in Aerospace Science and Technology (AAST) , 2019, DOI: 10.4236/aast.2019.42003
Abstract: In this paper, robust control problem is addressed for quad-rotor delivering unknown time-varying payloads. Firstly, the model of a quad-rotor carrying payloads is built. Dynamics of the payloads are treated as disturbances and added into the model of the quad-rotor. Secondly, to enhance system robust-ness, the extended state observer (ESO) is applied to estimate the disturbances from the payloads for feedback compensation. Then a type of predictive controller targeting multiple-input-multiple-output (MIMO) system is developed to degrade the influences caused by sudden changes from load-ing/dropping of the payloads. Finally, by making comparison with the con-ventional cascade proportional-integral-derivative (CPID) and the sliding mode control (SMC) approaches, superiority of the scheme developed is va-lidated. The simulation results indicate that the CPID method shows poor performance on attitude stabilization and the SMC shows input chattering phenomenon even it can achieve satisfied control performances.
四旋翼飞行器的滑模PID轨迹跟踪控制
Trajectory Tracking Control of Quad-rotor Unmanned Aerial Vehicles based on Sliding Mode PID
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刘云平,黄希杰,李先影,陈城
- , 2017,
Abstract: 针对传统PID在四旋翼飞行器轨迹跟踪控制方面存在的精度不高、鲁棒性差等不足,提出了一种滑模PID算法。并根据建立的四旋翼欧拉-庞卡莱动力学模型,设计滑模PID轨迹跟踪控制器。与传统PID算法相比,该算法通过选取PID滑模面,有效地提高系统的响应速度以及抗干扰的能力。通过MATLAB/Simulink,在不同条件下,分别对滑模PID和传统PID算法设计的控制系统进行仿真。仿真结果表明,该算法能够更为精确地跟踪期望轨迹,同时具有响应时间短,超调量小,鲁棒性强等优点。
In order to overcome the deficiencies of low accuracy and robustness for traditional PID controller in the trajectory tracking problem of quad-rotor unmanned aerial vehicles, a sliding mode PID algorithm is proposed. The dynamic model is established based on Euler-Poincare equation, and a sliding mode PID trajectory tracking controller is designed. The proposed algorithm with PID sliding surface provides a faster response and a higher anti-jamming ability than that of the traditional PID. Simulation is performed under different conditions by using MATLAB/Simulink. By compared with traditional PID controller the results show that the sliding mode PID controller has a better trajectory tracking performance, and it has faster response, smaller overshoot and stronger robustness, which verifies the effectiveness of the proposed algorithm
基于自适应动态逆的四旋翼机器人控制器设计
Adaptive Dynamic Inversion Controller for Quad Rotor Aerial Robot
 [PDF]

章志祥, 王立峰, 赫丛奎
Dynamical Systems and Control (DSC) , 2014, DOI: 10.12677/DSC.2014.31001
Abstract:
本文针对“X”型四旋翼空中机器人的轨迹跟踪问题,设计了一种自适应动态逆控制器。为了加强控制系统的鲁棒性,提出一个自适应动态矢量用于补偿模型逆误差,使系统达到Lyapunov渐近稳定。基于四旋翼机器人复杂的非线性动态模型,自适应动态逆控制器能在线估计并补偿四旋翼机器人的模型误差,使系统达到渐近稳定和轨迹跟踪的目的。MATLAB仿真实验表明该控制方案能满足系统稳定和轨迹跟踪的目的
This paper presents an adaptive dynamic inversion controller for trajectory tracking of quad rotor aerial robot with X type configuration. In order to enhance the robustness of dynamic inversion controller, an adaptive dynamic variable vector is used to compensate the model inversion error and achieve the asymptotic stability. On the base of a nonlinear dynamic model of the quad rotor, adaptive dynamic inversion nonlinear controller is synthesized for the purpose of stabilization and trajectory tracking. The proposed control method can compensate the deviation of model inaccuracy. It behaves perfectly at the reference altitude and trajectory track in MATLAB simulation.
四旋翼飞行器的自抗扰飞行控制方法
An active disturbance-rejection flight control method for quad-rotor unmanned aerial vehicles
 [PDF]

刘一莎,杨晟萱,王伟
控制理论与应用 , 2015, DOI: 10.7641/CTA.2015.50474
Abstract: 针对四旋翼飞行器参数不确定性和外部干扰敏感的问题, 本文提出一种基于自抗扰控制器的控制系统设 计方法. 在为期望姿态和高度安排过渡过程的基础上, 设计了扩张状态观测器对内扰和外扰进行估计并实时补偿, 能够很好地克服飞行器的强耦合性、模型不确定性以及风速变化等外部干扰问题. 此外本文还设计了非线性状态 误差反馈控制律来有效抑制跟踪误差. 在仿真平台上对自抗扰控制系统进行稳定控制、姿态跟踪、高度控制、抗扰 性及鲁棒性实验, 并与串级PID控制系统进行定量对比分析. 仿真结果表明, 本文所设计的自抗扰控制器不仅能够 很好地估计并补偿系统所受内外部干扰, 而且对四旋翼飞行器参数的不确定性具有较强的鲁棒性, 能够满足飞行器 姿态调节快速和高稳定度的控制要求, 性能指标明显优于串级PID控制器.
We design an active disturbance-rejection controller for the flight control of a quad-rotor unmanned aerial vehicle (UAV) to reduce the effects of the parameter variations and external disturbances. After arranging the transient dynamics of the desired attitude and height, we design an extended state observer to estimate and compensate for the impact of internal/external disturbances simultaneously, thus solving the problems of strong coupling and parametric uncertainties even in the presence of external disturbances such as varying-wind conditions. Moreover, a nonlinear state error feedback control law is also applied, which effectively reduces the tracking error. A series of experiments are conducted in simulation platform, and comparative analysis between active disturbance-rejection controller and cascade PID controller is made. Simulation results show that the active disturbance-rejection controller not only accurately estimates and compensates the internal/external disturbances but also implements the robust quad-rotor flight control under conditions of dynamic parametric uncertainties, meeting the design requirements of fast attitude maneuver and high stability, and showing a superior performance to cascade PID controller.
小型四旋翼无人机双闭环轨迹跟踪与控制
Dual-loop path tracking and control for quad-rotor miniature unmanned aerial vehicles
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许璟,蔡晨晓,李勇奇,邹云
控制理论与应用 , 2015, DOI: 10.7641/CTA.2015.50406
Abstract: 近年来, 无人飞行器控制繁荣发展对控制精度与品质要求日益增高. 为了应对这一挑战, 本文基于奇异摄 动的思想设计了四旋翼无人机非线性轨迹跟踪控制器. 首先, 基于牛顿欧拉定律建立了四旋翼无人飞行器非线性 奇异摄动形式的数学模型. 然后, 引入奇异摄动理论, 通过时间尺度分解的方法将系统解耦成内环快子系统和外环 慢子系统. 再者, 根据非线性动态逆的思想分别建立快、慢伪线性子系统, 并基于此分别设计外环轨迹跟踪、内环稳 定子控制器, 综合子控制器生成应用于原系统的全阶控制器以兼顾跟踪精度和鲁棒特性. 针对内环快系统, 采用线 性二次调节控制器以实现稳定快速地控制飞行器旋转动态; 针对外环慢系统, 运用经典的比例–微分–积分控制器 以跟踪所给定的轨迹. 最后给出了仿真实例说明本文结论的有效性.
The recent development of unmanned aerial vehicle flight control creates a strong demand for higher control accuracy and control quality. To meet such demands, we propose a nonlinear control strategy for path tracking control of quad-rotor miniature unmanned aerial vehicles (MAVs). Firstly, based on Newton-Euler’s laws, the nonlinear mathematical model of a quad-rotor MAV is built in singular perturbation form. By singular perturbation theory and time-scaling techniques, we decouple the system into the fast inner-loop sub-system and the slow outer-loop subsystem. Then, we build the fast pseudo-linear sub-system and the slow pseudo-linear sub-system based on the nonlinear dynamic inversion idea. On the basis of these subsystems, we respectively design the outer sub-controller for path tracking and the inner sub-controller for stabilization. These two sub-controllers are combined into a full-order controller for the original system to achieve the required tracking accuracy and robustness. In the fast inner sub-system, we use the LQG controller to realize the rapid control for the rotary dynamics of the aerial vehicle; in the slow outer sub-system, we employ the classical PID controller to track the given path. Simulation results show the effectiveness of the conclusions made in this paper.
基于四旋翼无人机快速获取大田植株图像的方法及其应用
Method for rapidly acquiring images of field-grown crops using a quad-rotor UAV and its application
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李晓鹏,胡鹏程,徐照丽,晋艳,杨宇虹,郑邦友,段涛,郭焱
- , 2017,
Abstract: 利用低空无人机获取农田信息,具有实时以及灵活性高、成本低等优势。为快速、精确监测大田规模化种植作物的生长发育状况,以四旋翼无人机为平台,结合数字图像技术,建立快速获取大田烟株中前期图像的方法。结果表明,在天空辐射条件较稳定的条件下,采用较低的飞行高度(如20 m)航拍获取田块图像,能够得到清晰的拼接图像和三维重建效果;采用基于决策树的植被分割算法将烟草和非植被部分分割后,得到较高精度的大田植株图像。在此基础上进行大田烟草缺苗数估测,所估算的缺苗数与实测值吻合较好。
Because of the characteristics of high flexibility and low cost,there are lots of advantages to use unmanned aerial vehicle(UAV)to collect the real-time information of field.In order to quickly monitoring the growth and development of crops grown in large scale field,a method for rapidly acquiring images of field-grown tobacco using quad-rotor UAV and digital image processing techniques was explored.The results show that under a relatively stable sky radiation condition,the images acquired with low flight height(e.g.20 m) can be used to produce rather high quality ortho-mosaic and 3D reconstruction.The images of individual field-grown tobacco plants were acquired using the vegetation segmentation algorithm based on decision tree to segment tobacco and non-vegetation part.The missing plant number of tobacco in individual plots was computed based on this algorithm and the results agree to the measured values well.Accordingly,this study provided a reliable way for rapidly and accurately accessing the growth and development of field-grown tobacco and studying plant phenotype in large scale.
含ESO的QTR无人机垂直起降模态分数阶滑模姿态控制
Attitude Control for Quad Tilt Rotor Aircraft Based on Fractional Order Sliding Mode Control Containing ESO
 [PDF]

刘海波,王和平,沈立顶
- , 2016,
Abstract: 针对四倾转旋翼飞行器姿态控制系统复杂非线性、强耦合、多输入多输出、存在复合干扰等特点,提出了一种分数阶滑模控制的设计方法。利用分数阶微积分算子的积分权重随时间的推移逐渐减小的特性,柔化作用在被控系统上的能量,减小整数阶微积分滑模面的超调现象,设计了分数阶微积分滑模面。并针对传统幂次趋近律收敛时间长、速度慢、抖震严重等不足,提出了一种具有二阶滑模特性的新型快速趋近律。在此基础上采用扩张状态观测器在线对复合干扰进行估计和补偿。仿真结果表明,相比传统整数阶滑模控制,所提控制方案具有良好的控制性能。
For the attitude control of quad tilt rotor (QTR) aircraft with complex nonlinear, strong coupling, multiple input and multiple output, unknown external disturbances, the method of fractional order sliding mode control is proposed. Using the characteristics of the gradually decrease over time of fractional calculus operator integral weight, reduced the overshoot phenomenon of the sliding mode surface of integer order calculus. In order to solve the problem of long convergence time and shake out serious of the traditional reaching law, put forward a new fast reaching law model with characteristics of second order sliding mode. Considering the existence of complex disturbances, the extended state observer is used to estimate and compensate the composite disturbance on line. By comparing with the traditional integer order sliding mode control, simulation experiment results show that the proposed control scheme has good control performance
无 氧 条 件 下TiO2 薄 膜 界 面 光 催 化 反 应 的XPS 研 究  [PDF]
杨喜昆,胡显智,何 兵,楚国栋
分子催化 , 2009,
Abstract: 设 计 利 用 X 射 线 光 电 子 能 谱 仪 的 高 真 空 系 统 作 为 无 氧 条 件 下 光 催 化 反 应 和 分 析 的 场 所 , 研 究 真 空 无 氧 环 境 和 大 气 有 氧 环 境 中 紫 外 光 激 发 TiO2 薄 膜 表 面 的 光 催 化 反 应 , 并 对 无 氧 条 件 下 TiO2 薄 膜 降 解 亚 甲 基 蓝 进 行 初 步 探 索 . 结 果 表 明 , 在 大 气 有 氧 和 真 空 无 氧 条 件 下 TiO2 薄 膜 经 紫 外 光 照 后 , 表 面 的 化 学 组 成 和 化 学 状 态 均 发 生 了 变 化 ; 在 有 氧 环 境 中 TiO2 薄 膜 表 面 氧 含 量 增 加 , 而 在 无 氧 环 境 中 TiO2 薄 膜 表 面 氧 含 量 减 少 . TiO2 薄 膜 表 面 的 吸 附 氧 是 维 持 无 氧 条 件 下 光 催 化 反 应 的 重 要 原 因 , 增 加 薄 膜 表 面 吸 附 氧 的 含 量 能 提 高 TiO2 薄 膜 在 无 氧 环 境 中 的 催 化 活 性 . 此 外 , 无 氧 条 件 下 TiO2 薄 膜 降 解 亚 甲 基 蓝 光 催 化 反 应 过 程 中 , 亚 甲 基 蓝 分 子 只 是 脱 去 了 某 个 含 氮 的 基 团 , 生 成 了 中 间 产 物 , 而 并 没 有 完 全 降 解 .
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