四旋翼无人机系统具有参数不确定性及强耦合性的特点,其飞行性能容易受到外部干扰而下降.为了保证四旋翼无人机飞行的稳定性,本文提出了一种基于改进线性扩张状态观测器(Linear Extended State Observer,LESO)的模糊线性自抗扰控制方法...四旋翼无人机系统具有参数不确定性及强耦合性的特点,其飞行性能容易受到外部干扰而下降.为了保证四旋翼无人机飞行的稳定性,本文提出了一种基于改进线性扩张状态观测器(Linear Extended State Observer,LESO)的模糊线性自抗扰控制方法.通过模糊算法自适应调节线性自抗扰控制器的参数,基于Levant跟踪微分器跟踪四旋翼无人机位置及姿态角的二阶微分信号进而提取四旋翼无人机系统的总扰动,使用总扰动偏差及偏差的微分作为输入的模糊控制器来优化LESO对总扰动的估计精度.此外,分析了LESO的收敛性及闭环系统的稳定性.最后通过对比仿真验证了所提控制策略的有效性,并从系统的控制信号,动态响应能力和抗干扰能力等方面对控制方案的性能进行了定量分析.展开更多
针对常见控制策略在大型液压设备控制方面存在控制精度低与算法太复杂的问题,提出了基于线性扩张状态观测器(linear extended state observer,LESO)的线性时变模型预测控制(linear time-varying model predictive control,LTV-MPC)策略...针对常见控制策略在大型液压设备控制方面存在控制精度低与算法太复杂的问题,提出了基于线性扩张状态观测器(linear extended state observer,LESO)的线性时变模型预测控制(linear time-varying model predictive control,LTV-MPC)策略。通过起竖液压系统状态空间方程,设计了LESO实时估计系统当前状态;通过LTV-MPC输出比例阀电压信号的最优解。通过仿真与试验,验证所提方法的有效性。结果表明:无干扰时,相较于其他控制策略,LESO-LTV-MPC控制误差为0.014%,具有较高的控制精度;施加大干扰时,LESO-LTV-MPC控制误差为0.223%,具有较强的鲁棒性。因此,该控制策略能够有效提升起竖液压系统的性能。展开更多
With the increasing demand for interactive aerial operations,the application of aerial manipulators is becoming more promising.However,there are a few critical problems on how to improve the energetic efficiency and p...With the increasing demand for interactive aerial operations,the application of aerial manipulators is becoming more promising.However,there are a few critical problems on how to improve the energetic efficiency and pose control of the aerialmanipulator forpractical application.In this paper,a novel cable-drivenaerialmanipulatorused for remote water sampling is proposed and then its rigid-flexible coupling dynamics model is constructed which takes joint flexibility into account.To achieve high precision joint position tracking under lumped disturbances,a newly controller,which consists of three parts:linear extended state observer,adaptive super-twisting strategy,and fractional-order nonsingular terminal sliding mode control,is proposed.The linear extended state observer is adopted to approximate unmeasured states and unknown lumped disturbances and achieve model-free control structure.The adaptive super-twisting strategy and fractional-order nonsingular terminal sliding mode control are combined together to achieve good control performance and counteract chattering problem.The Lyapunovmethod is utilized to prove the overall stability and convergence of the system.Lastly,various visualization simulations and ground experiments are conducted,verifying the effectiveness of our strategy,and all outcomes demonstrate its superiorities over the existing control strategies.展开更多
The trajectory tracking control for a 6-DOF robot manipulator with multiple inputs and outputs,non-linearity and strong coupling is studied.Firstly,a dynamical model for the 6-DOF robot manipulator is designed.From th...The trajectory tracking control for a 6-DOF robot manipulator with multiple inputs and outputs,non-linearity and strong coupling is studied.Firstly,a dynamical model for the 6-DOF robot manipulator is designed.From the view point of practical engineering,considering the model uncertainties and external disturbances,the robot manipulator is divided into 6 independent joint subsystems,and a linear active disturbance rejection controller(LADRC)is developed to track trajectory for each subsystem respectively.LADRC has few parameters that are easy to be adjusted in engineering.Linear expansion state observer(LESO)as the uncertainty observer is able to estimate the general uncertainties effectively.Eventually,the validity and robustness of the proposed method adopted in 6-DOF robot manipulator are demonstrated via numerical simulations and 6-DOF robot manipulator experiments,which is of practical value in engineering application.展开更多
相比燃油拖拉机,电动拖拉机具有节能高效、绿色清洁的优点。分布式驱动电动拖拉机结构简单、控制维度多,能进一步提高电动拖拉机的工作效率和作业精度。但是电机检测转速噪声导致轮毂电机速度波动严重,复杂路面及多种作业工况下进一步...相比燃油拖拉机,电动拖拉机具有节能高效、绿色清洁的优点。分布式驱动电动拖拉机结构简单、控制维度多,能进一步提高电动拖拉机的工作效率和作业精度。但是电机检测转速噪声导致轮毂电机速度波动严重,复杂路面及多种作业工况下进一步加剧了上述问题,严重降低了拖拉机的作业质量。针对上述问题,该研究提出一种基于sigmoid滤波器的线性自抗扰控制(linear active disturbance rejection control,LADRC)以提高轮毂电机的转速稳定性和抗扰动能力。该控制策略在传统LADRC的基础上引入sigmoid滤波器至扩张状态观测器(extended state observer,ESO),根据输入噪声信号误差变化改变滤波器带宽,以抑制观测误差中的中高频干扰信号,同时避免滤波器积分环节对轮毂电机速度跟踪快速性的影响,具有较快的收敛性。搭建试验平台对所提出控制策略进行试验验证,结果表明:与传统LADRC策略相比,本文所提控制策略在变速和变载工况下的转速脉动分别减小了32%和41.67%,iq电流脉动分别减小了6.25%和4.17%,可在快速、准确跟踪给定转速的同时,大幅提高轮毂电机驱动系统的噪声抑制性能,为复杂环境下电动拖拉机高精度作业提供技术参考。展开更多
文摘四旋翼无人机系统具有参数不确定性及强耦合性的特点,其飞行性能容易受到外部干扰而下降.为了保证四旋翼无人机飞行的稳定性,本文提出了一种基于改进线性扩张状态观测器(Linear Extended State Observer,LESO)的模糊线性自抗扰控制方法.通过模糊算法自适应调节线性自抗扰控制器的参数,基于Levant跟踪微分器跟踪四旋翼无人机位置及姿态角的二阶微分信号进而提取四旋翼无人机系统的总扰动,使用总扰动偏差及偏差的微分作为输入的模糊控制器来优化LESO对总扰动的估计精度.此外,分析了LESO的收敛性及闭环系统的稳定性.最后通过对比仿真验证了所提控制策略的有效性,并从系统的控制信号,动态响应能力和抗干扰能力等方面对控制方案的性能进行了定量分析.
文摘针对常见控制策略在大型液压设备控制方面存在控制精度低与算法太复杂的问题,提出了基于线性扩张状态观测器(linear extended state observer,LESO)的线性时变模型预测控制(linear time-varying model predictive control,LTV-MPC)策略。通过起竖液压系统状态空间方程,设计了LESO实时估计系统当前状态;通过LTV-MPC输出比例阀电压信号的最优解。通过仿真与试验,验证所提方法的有效性。结果表明:无干扰时,相较于其他控制策略,LESO-LTV-MPC控制误差为0.014%,具有较高的控制精度;施加大干扰时,LESO-LTV-MPC控制误差为0.223%,具有较强的鲁棒性。因此,该控制策略能够有效提升起竖液压系统的性能。
基金supported by the National Natural Science Foundation of China (52005231,52175097)Social Development Science and Technology Support Project of Changzhou (CE20215050).
文摘With the increasing demand for interactive aerial operations,the application of aerial manipulators is becoming more promising.However,there are a few critical problems on how to improve the energetic efficiency and pose control of the aerialmanipulator forpractical application.In this paper,a novel cable-drivenaerialmanipulatorused for remote water sampling is proposed and then its rigid-flexible coupling dynamics model is constructed which takes joint flexibility into account.To achieve high precision joint position tracking under lumped disturbances,a newly controller,which consists of three parts:linear extended state observer,adaptive super-twisting strategy,and fractional-order nonsingular terminal sliding mode control,is proposed.The linear extended state observer is adopted to approximate unmeasured states and unknown lumped disturbances and achieve model-free control structure.The adaptive super-twisting strategy and fractional-order nonsingular terminal sliding mode control are combined together to achieve good control performance and counteract chattering problem.The Lyapunovmethod is utilized to prove the overall stability and convergence of the system.Lastly,various visualization simulations and ground experiments are conducted,verifying the effectiveness of our strategy,and all outcomes demonstrate its superiorities over the existing control strategies.
基金Supported by the National Natural Science Foundation of China(No.11672290)
文摘The trajectory tracking control for a 6-DOF robot manipulator with multiple inputs and outputs,non-linearity and strong coupling is studied.Firstly,a dynamical model for the 6-DOF robot manipulator is designed.From the view point of practical engineering,considering the model uncertainties and external disturbances,the robot manipulator is divided into 6 independent joint subsystems,and a linear active disturbance rejection controller(LADRC)is developed to track trajectory for each subsystem respectively.LADRC has few parameters that are easy to be adjusted in engineering.Linear expansion state observer(LESO)as the uncertainty observer is able to estimate the general uncertainties effectively.Eventually,the validity and robustness of the proposed method adopted in 6-DOF robot manipulator are demonstrated via numerical simulations and 6-DOF robot manipulator experiments,which is of practical value in engineering application.
文摘相比燃油拖拉机,电动拖拉机具有节能高效、绿色清洁的优点。分布式驱动电动拖拉机结构简单、控制维度多,能进一步提高电动拖拉机的工作效率和作业精度。但是电机检测转速噪声导致轮毂电机速度波动严重,复杂路面及多种作业工况下进一步加剧了上述问题,严重降低了拖拉机的作业质量。针对上述问题,该研究提出一种基于sigmoid滤波器的线性自抗扰控制(linear active disturbance rejection control,LADRC)以提高轮毂电机的转速稳定性和抗扰动能力。该控制策略在传统LADRC的基础上引入sigmoid滤波器至扩张状态观测器(extended state observer,ESO),根据输入噪声信号误差变化改变滤波器带宽,以抑制观测误差中的中高频干扰信号,同时避免滤波器积分环节对轮毂电机速度跟踪快速性的影响,具有较快的收敛性。搭建试验平台对所提出控制策略进行试验验证,结果表明:与传统LADRC策略相比,本文所提控制策略在变速和变载工况下的转速脉动分别减小了32%和41.67%,iq电流脉动分别减小了6.25%和4.17%,可在快速、准确跟踪给定转速的同时,大幅提高轮毂电机驱动系统的噪声抑制性能,为复杂环境下电动拖拉机高精度作业提供技术参考。
