带有完整约束的双吊车系统输入整形控制

作为一种重要的物料运输工具,桥式吊车在各类工业场景中发挥着举足轻重的作用.然而随着负载体积/质量的增大,很多时候不得不使用两台吊车来协同运送负载.目前对于这类双吊车系统的防摆研究仍然较少.本文针对这一情况,率先提出了一种输入整形控制方法.具体来说,首先分析了双吊车系统中存在的完整约束,通过对系统模型的合理简化,在不失准确性的情况下获得了台车位移与负载姿态角之间的近似动力学关系.在此基础上,求取出系统真实的振荡周期并设计出了合适的输入整形器.该整形器能够在不影响台车定位的情况下,充分抑制负载的摆动,并且对系统参数不确定性具有良好的鲁棒性.仿真和实验结果也证明了这一点.     

基于滑模方法的桥式吊车系统的抗摆控制

针对桥式吊车这类欠驱动系统，提出一种基于滑模控制的抗摆方法．该方法将系统状态分成两组。构造出一种双层滑动平面．结合桥式吊车系统数学模型的特点。求取了总的滑模控制量并进一步设计了控制器的参数．采用Lyapunov方法，从理论上证明了各级滑动平面的稳定性．仿真结果验证了该方法对于桥武吊车系统抗摆控制的有效性．     

采用神经网络的双吊车自适应防摆控制

由于工业实践对运输能力提出了更高的要求, 双吊车的应用日益广泛. 然而其动力学模型非线性很强, 因此控制器结构十分复杂. 另一方面, 大型货物的摆动很难抑制, 这给双吊车的自动化带来了巨大的挑战. 为了处理以上问题, 首先, 采用神经网络准确地估计了系统的模型, 在此基础上提出了一种自适应防摆控制方法, 很好地实现了双吊车系统的防摆控制; 然后, 采用李雅普诺夫方法, 严格地证明了系统在平衡点的渐近稳定性; 最后, 通过大量的实验结果, 验证了该方法具有良好的性能.     

欠驱动桥式吊车消摆跟踪控制

对于桥式吊车系统而言,其控制目标是将货物快速、精确、摆动尽可能小地运送到目标位置.为此,本文提出了一种新型的轨迹跟踪控制策略,可在保证负载快速平稳运送的同时,有效地抑制并消除整个过程中负载的摆动.具体而言,通过对吊车动力学模型进行一系列的变换,设计了一种新颖的跟踪控制器,并对闭环系统信号的有界性与收敛性进行了理论分析.与调节控制方法相比,本文方法可保证台车的平滑启动与运行;此外,本方法放宽了已有轨迹跟踪控制方法对参考轨迹的约束条件,更具实用性与一般性.实验结果表明,本文设计的控制器能取得优于已有方法的控制效果,并对外界干扰具有很强的鲁棒性.     

考虑状态约束的五自由度塔式吊车多目标最优轨迹规划

为了提高塔式吊车的实际工作效率,往往需要在驱动旋臂和台车的同时改变绳长,以同步实现负载的运输与起落吊运.然而,目前针对变绳长塔式吊车控制问题的研究非常有限,依然处于起步阶段.对于变绳长塔式吊车而言,如何在保证系统良好暂态性能的基础上,减少运输时间、降低系统能耗,并同时实现综合最优是一个亟待解决的实际问题.为此,本文提出...     

欠驱动桥式吊车系统自适应控制

针对桥式吊车这类非线性欠驱动系统, 提出了一种基于耗散理论的自适应控制器. 它能够有效地抑制运输过程中负载的摆动, 并将其快速准确地运送到指定的位置. 相比其他吊车控制系统, 这种控制器无需准确测量台车和负载质量以及吊绳长度, 可以根据系统响应情况来对这些参数进行在线估计, 这将极大地方便控制器在实际吊车系统中的推广应用. 对于闭环系统的稳定性, 文中通过李雅普诺夫理论及拉塞尔不变性原理进行了证明, 仿真结果也证实了这种自适应控制器能够对吊车系统进行良好的控制.     

基于自适应方法的桥式吊车的防摇定位控制器的设计

针对一类欠驱动非线性桥式吊车,设计了一种自适应控制器,它不需要对吊车模型进行近似解耦或线性化处理,不需要事先知道桥吊的精确的数学模型的参数信息,在负载质量等参数发生变化的情况下,能够实现对桥吊小车的精确定位与负载摆动的有效抑制,文中同时对该方法的稳定性进行了理论分析.该控制方法具有结构简单,计算量小的特点.数值仿真结果证实了本控制方法的良好效果.     

桥式吊车系统的分级滑模控制方法

该文针对桥式吊车这一类欠驱动系统提出了一种分级滑模控制方法.该方法将系统状态分成两组,分别构造第一级滑动平面,并求取各个子滑动平面上的等效控制量.然后再构造第二级滑动平面,采用Lyapunov稳定定理获得最终的控制量.该控制量包含各子滑动平面的等效控制分量,因此能够保证系统状态沿着各个子滑动平面滑动.该文从理论上证明了各级滑动平面的渐近稳定性,并且通过仿真验证了该结果.     

基于LQR和变论域模糊控制的吊车防摆控制

针对吊车这类非线性欠驱动系统。提出一种基于LQR和变论域模糊控制的消摆控制方法．先将该系统分解为垂直运动和水平运动两个子系统;然后用变论域方法寻找最优反馈增益,从而解决了在绳长连续变化时,吊车系统的防摆优化控制问题．仿真结果表明了该方法的有效性。     

欠驱动旋转双摆系统的建模与仿真

研究倒立摆控制问题,针对旋转双摆系统这一新颖的欠驱动机械系统,而旋转双摆系统是由一个驱动的旋转臂和两个未驱动的旋转摆杆组成,选取驱动臂和两个摆杆的旋转角度作为系统的广义坐标,系统存在不稳定平衡点.为对系统进行稳定性控制,采用拉格朗日方程的方法建立了其动力学模型并总结了系统模型的特殊性质.为了便于进行稳定控制器的设计,给出了近似条件下旋转双摆系统的线性化.对动力学模型进行了仿真实验,仿真结果表明实现了系统的稳定性控制,说明了模型的有效性.     

Tracking and load sway reduction for double‐pendulum rotary cranes using adaptive nonlinear control approach

Because of the existence of rotational boom motion, the load sway characteristics is more complex. In particular, when the sway presents double‐pendulum phenomenon, the design of the controller is more challenging. Furthermore, the uncertain parameters and external disturbances in crane system make it difficult for traditional control methods to obtain satisfactory control performance. Hence, this paper presents an adaptive nonlinear controller based on the dynamic model of double‐pendulum rotary crane. Unlike a traditional method, the proposed one does not need to linearize the crane system for controller design; therefore, the control performance can be guaranteed even if the system states are far away from the equilibrium point. By using Lyapunov technique and LaSalle's invariance theorem, it is strictly proved that the whole control system is asymptotically stable at the equilibrium point. The effectiveness of the presented controller is demonstrated via comparative simulations.     

适于长距离运输的分段吊车模糊控制

针对长距离吊车运输系统的特征,提出了分段切换因子模糊控制方法.该方法使用两个子模糊控制器分别用于抗摆和定位控制,并运用实值遗传算法选取模糊控制器的分段切换因子.仿真结果表明:该方法保证了定位精度并能有效地抑制超调,在加速阶段、运输阶段和减速阶段能够使载荷摆角最小,并且能够在目标位置进行消摆控制,其性能优于传统二次型最优控制.     

Design of motion trajectory and tracking control for underactuated cart‐pendulum system

A cart‐pendulum system is a nonlinear underactuated mechanical system with two degrees of freedom. This paper addresses the motion trajectory design and tracking control problems for this underactuated system. First, a friction‐like control law is designed for the system. Then, the characteristics of the closed‐loop control system are analyzed. Second, a new method of constructing an optimal trajectory for the system is developed. Then, a tracking control law is designed to quickly track the constructed trajectory. It guarantees that the motion control of the cart‐pendulum system is achieved along a reference trajectory. Finally, a numerical example is presented to demonstrate the effectiveness of the theoretical results. This study constructs an optimal trajectory for the cart‐pendulum system in its whole motion space and solves the motion control objective by tracking the constructed trajectory. It has many advantages compared with other motion control methods, eg, the optimal motion control objective of the system is achieved by a single control law; and the motion process and transient characteristics (eg, the settling time) of the control system can be accurately predicted.     

A pure neural network controller for double‐pendulum crane anti‐sway control: Based on Lyapunov stability theory

Crane systems have been widely applied in logistics due to their efficiency of transportation. The parameters of a crane system may vary from each transport, therefore the anti‐sway controller should be designed to be insensitive to the variation of system parameters. In this paper, we focus on pure neural network adaptive tracking controller design issue that does not require the parameters of crane systems, i.e. the trolley mass, the payload mass, the cable lengths, and etc. The proposed neural network controller only requires the output feedback signals of the trolley, i.e. the position and the velocity, which means no sway measuring equipment is needed. The Lyapunov method is utilized to design the weights update law of neural network, and the robustness of the proposed controller is proved by the Lyapunov stability theory. The results of numerical simulations show that the proposed neural network controller has excellent performance of trolley position tracking and payload anti‐sway controlling.     

The switching algorithm for the control of overhead crane

This paper presents the fuzzy logic based method to control the trolley cranes. The information, including the position of trolley, load swing and the differences between the present and previous signals, are applied to derive the proper power to drive the trolley. An easy but effective switching algorithm is investigated to improve the control of trolley and suppress the load swing in this paper. This also helps to enhance the control power of the crane to depart from the deadzone. Finally, several experiments through the scaled trolley crane demonstrate the effectiveness of the scheme.This work was supported by the National Science Council of the Republic of China under Grant NSC-91-2213-E-231-007.