Intelligent anti-swing control for bridge crane

A new intelligent anti-swing control scheme,which combined fuzzy neural network(FNN) and sliding mode control(SMC) with particle swarm optimization(PSO),was presented for bridge crane.The outputs of three fuzzy neural networks were used to approach the uncertainties of the positioning subsystem,lifting-rope subsystem and anti-swing subsystem.Then,the parameters of the controller were optimized with PSO to enable the system to have good dynamic performances.During the process of high-speed load hoisting and dropping,this method can not only realize the accurate position of the trolley and eliminate the sway of the load in spite of existing uncertainties,and the maximum swing angle is only ±0.1 rad,but also completely eliminate the chattering of conventional sliding mode control and improve the robustness of system.The simulation results show the correctness and validity of this method.

A practical fuzzy controllers scheme of overhead crane

This paper presents fuzzy-based design for the control of overhead crane. Instead of analyzing the complex nonlinear crane system, the proposed approach uses simple but effective way to control the crane. There are twin fuzzy controllers which deal with the feedback information, the position of trolley crane and the swing angle of load, to suppress the sway and accelerate the speed when the crane transports the heavy load. This approach simplifies the designing procedure of crane controller; besides, the twin controller method reduces the rule number when fulfilling the fuzzy system. Finally, experimental results through the crane model demonstrate the effectiveness of the scheme.

Adaptive Proportional-Derivative Sliding Mode Control Law With Improved Transient Performance for Underactuated Overhead Crane Systems

In this paper, an adaptive proportional-derivative sliding mode control(APD-SMC) law, is proposed for 2D underactuated overhead crane systems. The proposed controller has the advantages of simple structure, easy to implement of PD control, strong robustness of SMC with respect to external disturbances and uncertain system parameters, and adaptation for unknown system dynamics associated with the feedforward parts. In the proposed APD-SMC law, the PD control part is used to stabilize the controlled system, the SMC part is used to compensate the external disturbances and system uncertainties,and the adaptive control part is utilized to estimate the unknown system parameters. The coupling behavior between the trolley movement and the payload swing is enhanced and, therefore, the transient performance of the proposed controller is improved.The Lyapunov techniques and the La Salle's invariance theorem are employed in to support the theoretical derivations. Experimental results are provided to validate the superior performance of the proposed control law.

Damage Identification of General Overhead Travelling Crane Structure Based on Model Updating by Sensitivity

A model based damage identification was proposed by facilitating parameter sensitivity analysis and applied to a general overhead travelling crane.As updating reference data,experimental modal frequency was obtained by operational modal analysis(OMA)under ambient excitation.One dimensional damage function was defined to identify the damage by bending stiffness.The results showed that the model updating method could locate the damage and quantitatively describe the structure.The average error of eigenvalues between updated model analysis and the experimental results was less than 4% which proved the accuracy reliable.The comparison of finite element analysis and the test results of the deflection under the capacity load further verified the feasibility of this method.

The Application of PLC in the Overhead Crane

This paper is about the application of PLC (Model S5 135U made by Siemens) in the overhead crane.It is mainly about the working principles and application of PLC Model S5 135U.

Rehabilitation of Overhead Crane in HPP

This paper presents a case study on the repair of a mechanical component of an overhead crane.The problem was initially identified through on-site inspection and analysis of the crane’s performance.The mechanical part was found damaged,leading to safety concerns and operational inefficiencies.The paper details the process of diagnosing the issue,developing a repair plan,and executing the repair work.The repair plan involved replacing the damaged component with a new one and conducting additional maintenance work to ensure optimal performance.The paper also discusses the outcomes of the repair work,which led to improved safety and increased efficiency of the overhead crane.The case study provides insights into the importance of regular maintenance and on-site inspections in ensuring the safe and efficient operation of mechanical systems.

Detection of mechanical stress in the steel structure of a bridge crane

A significant negative aspect in the operation of bridge-type cranes are the technical problems associated with wear of the wheels and the crane track,which causes crane skewing.The main causes of crane skewing include unevenness of the crane track,unequal loading of the traction drives depending on the position of the crane trolley,slips and different sizes of travel wheels and combinations of these causes.Firstly,this paper presents a design solution that can be used to detect the magnitude of mechanical stress and deformation of the steel structure of the crane,caused by the effects of skewing.The mechanical stress generated by the transverse forces of the deformed geometric shape of the crane bridge structure is recorded by mechanical stress detectors installed in the inner corners of the crane bridge.The resulting electrical signal from element mechanical voltage detectors,loaded by axial forces,can be used for feedback control of separate crane travel drives controlled by frequency converters.Secondly,this paper presents the calculation of the lateral transverse forces according to CSN 270103 and the determination of the values of mechanical stresses of the deformed steel structure of the crane bridge of a two-girder bridge crane using the finite element method in the program MSC.MARC 2019.Finally,this paper presents the structural and strength design of mechanical stress detectors and the conclusions of laboratory tests of axial force loading of mechanical stress detectors on the test equipment.At the same time,it presents records of the measured axial forces acting in the mechanical stress detectors,arising from the deformation and warping of the crane bridge by the known magnitude of the axial force acting on the crossbeam and from the deformation of the crane bridge caused by the crane operating modes.

GZ350型自走式果园高架机的设计与试验

为提高果园管理中果树修剪与采摘的效率,设计了一款内燃机驱动、具有侧倾角调节和升降控制功能的自走式果园高架机。在确定果园高架机总体技术要求基础上,对其工作原理、结构特点进行分析,通过理论计算,对高架机的关键部件进行设计与选型,采用三维软件对高架机进行建模,且加工生产样机进行测试试验。试验结果表明:整机最大行驶速度为3.7km/h,最小离地间隙高度为85mm,升降高度调节范围为650~3000mm,最大运载负载为350kg,最大举升负载为210kg,能够满足一般果园采摘与管理等作业,可提高农业作业安全性,降低人员劳动强度。

桥式起重机分布式质量吊重系统双摆滑模控制

随着吊装作业的多元化发展,起重机吊装对象也从传统的质点式吊重向分布式质量吊重方向发展。针对桥式起重机在吊装分布式质量吊重时吊重的大摆角抑制和小车定位控制问题,提出了两种基于滑模控制理论的、用于吊重消摆和小车快速定位的方法。首先,综合考虑了桥式起重机吊装对象的结构特征、小车电机的驱动特性、摩擦阻力以及环境中的随机扰动对吊装作业的影响,建立了桥式起重机分布式质量吊重系统的非线性双摆动力学模型;然后,设计了桥式起重机分布式质量吊重系统的非线性双摆动力学普通滑模控制器(OSMC)和分层滑模控制器(HSMC),采用Lyapunov函数和Barbalat引理证明了闭环系统的稳定性;最后,利用数值仿真研究了OSMC和HSMC在分布式质量吊重减摆控制方面的性能差异。仿真及研究结果表明:与OSMC相比,采用HSMC不仅可以在12 s内实现小车精确定位目的,而且可以实现对分布式质量吊重在5°~9°摆动范围下的快速抑制目的,完成了对系统状态变量的有效控制;同时,对比结果表明HSMC对起重机系统内部和外部扰动变化有很强的鲁棒性和抗干扰性。

Comparative analysis on the performance of different types of input-and command-shaping controllers in minimizing payload residual vibration of an overhead crane with an inclined supporting track

Reducing the effects of external disturbance on overhead crane systems is crucial,as they can impair the controller performance and cause excessive vibrations or oscillations of the payloads.One such external disturbance is the inclination of the supporting track of the crane trolley,which causes the system dynamics model to change.An open-loop control strategy is widely utilized to control the payload sway motion and generally does not require any alterations in the physical structure of a system or the installation of sensors and/or actuators.Input and command shaping are two common open-loop control techniques applied to control overhead cranes.In this paper,the effect of moving an overhead crane system along an inclined supporting track is investigated.In addition,the ability of different types of input-and command-shaping control schemes to suppress the residual vibrations due to trolley track inclination is demonstrated.Two types of input-shaping controllers,which are double-step,zero vibration,and one command waveform(WF)shaper based on a trigonometric function,are used and tested.A linear equation of motion of the overhead crane resting on an inclined surface is developed to simulate the overhead crane and payload motion.The effectiveness of the different types of open-loop controllers to suppress residual vibrations is verified by both simulation and experimental results.In addition,a new WF command shaper is proposed and designed to overcome track inclination while eliminating payload residual vibration.A comprehensive comparative analysis,both numerically and experimentally,is performed on the new proposed shaper to measure its effectiveness in handling inclination when compared to other types of open-loop controllers.The new shaper outperforms other controllers in eliminating payload residual vibration for a wider range of inclination angles.

新型电梯及天车用随行通信光电复合缆的研制

随着5G的发展,智慧电梯应用为乘梯人带来更加安全、信息畅通、智慧屏交互等升级体验,但这需要实现电梯5G信号全覆盖。在现有电梯及天车设备用电线电缆的基础上,通过融入光单元结构、研制柔性护套材料、改进挤塑工艺等方法,研制出一款新型电梯及天车用随行通信光电复合缆。与原有电梯及天车内常规电缆相比,研制出的复合缆可以满足电梯及天车设备中更高的信号传输速率和带宽要求,可以在长时间往复运动过程中更好地保护光电信号单元,提高产品使用寿命,助力电梯及天车行业的智能化发展。

桥式起重机神经网络自适应滑模定位防摆控制

针对桥式起重机非线性、存在外界干扰的特点,提出了一种神经网络自适应滑模控制器。首先采用拉格朗日法建立桥式起重机动力学模型;然后在分层滑模控制器的基础上,设计了径向基函数神经网络权值自适应更新率,利用径向基函数神经网络补偿系统的非线性与外界干扰引起的不确定上界,并利用粒子群算法对控制器参数寻优,通过构造Lyapunov函数证明了系统的稳定性;最后设计了1组仿真实验和1组在搭建的实验平台上的验证实验,仿真结果表明:在非线性及外界干扰作用下,神经网络自适应滑模控制器可以快速实现小车定位和负载消摆,控制器可以消除不确定上界对系统的影响。实验结果也表明,所设计的控制器可以使桥式起重机达到控制目标,具有一定的抗干扰能力。

基于轨迹规划的欠驱动桥式起重机防摆控制

针对桥式起重机的台车在启动时出现较大振动冲击的现象,以及台车在水平移动时伴有负载的升降而造成负载摆动过大等安全隐患问题,提出了一种基于轨迹规划的耦合跟踪防摆控制器。首先,规划S形位移轨迹作为参考轨迹;其次,构造含有台车位移和负载摆角的未知形式的耦合函数;最后,利用能量法设计非线性耦合跟踪防摆控制器来实现对参考轨迹的跟踪。该控制器减小了台车启动时的冲击,保证了台车运行的平稳性和准确性,有效地抑制并消除了负载的摆动。仿真和实验结果表明,该控制器的控制效果优于耦合控制器和自适应跟踪控制器,并且该控制器具有较强的鲁棒性。

基于单目视觉实时测量桥式起重机负载摆角

针对目前基于视觉的桥式起重机负载摆角测量方法实时性较低,且没有考虑由运动模糊导致的测量精度下降问题,将一个对旋转和倾斜不敏感的球形标识物安装在负载上,设计一种计算灰度概率分布特征余弦相似度的方法,结合卡尔曼滤波器实时跟踪标识物。提出一种基于背景灰度值的局部自适应分割算法,使模糊边缘变清晰。从感兴趣区域(region of interest,ROI)的中心向周围8个方向寻找灰度梯度最大的点作为模糊图像的边缘点,对这些点采用最小二乘法进行拟合确定标识物位置。通过几何关系模型计算负载摆角。实验结果表明,本文方法在图像模糊情况下的测量精度和实时性能更优。

天车技术故障及钢丝绳脱槽优化措施探析

冷轧厂天车使用频繁、吊运重物多,经常因磨损而出现多种故障问题,特别是在镀锌线维修时,更换冷却塔顶辊包布作业对天车的使用需求较为特别,时常会导致钢丝绳滑出轮槽脱离导向轮的现象发生,造成生产事故。基于冷轧厂天车使用现状,分析天车钢丝绳的日常保养和维护要点,以及时消除一些故障和隐患,并针对不同的技术问题采取相应的优化措施,以确保天车的长期稳定运行,保证安全生产。

浅谈井下架空人车的各种保护设计

基于井下环境的愈发复杂,当前架空人车的实际运行仍存在较多的安全问题,如何有效结合常见故障进行保护设计,也成为很多矿企需要考虑的问题。基于此,分析了井下架空人车的常见故障类型,然后进行具体的保护设计,讨论架空人车保护的运行效果,表明能满足矿企的安全开采需要。

基于改进双闭环模糊PID控制算法的桥式起重机控制系统

针对起重机在吊装作业时产生的负载摇摆以及行车定位的问题,提出了一种改进双闭环模糊PID控制算法,利用拉格朗日方程建立工业起重机防摇摆及行车定位控制系统数学模型。将该算法运用在建立的模型中,并在Simulink仿真平台上分别设计了PID控制系统、模糊PID控制系统和改进双闭环模糊PID控制系统进行对比实验。仿真实验的结果表明,与PID控制系统以及模糊PID控制系统相比,改进双闭环模糊PID控制系统对摆角的抑制能力分别提高了32.6%、16.5%,对小车的位置调节时间分别减少了5.442、2.743 s,且无超调量。改进双闭环模糊PID控制系统的精确性更好、稳定性更强,可以更好地满足桥式起重机系统的控制要求。

铜冶炼企业中原料库智能天车的功能需求及关键技术探析

铜冶炼行业中原料的搬运大多依靠人工驾驶天车进行,员工劳动强度大,天车运行效率不高,信息及现场管理原始粗放,急需借助智能化手段优化原有作业模式,以减轻员工劳动强度,提高生产效率,改善工作环境,实现无人化管理。针对以上问题及优化目标,对多品种物料原料库智能天车的软硬件功能需求以及精准定位技术、吊具防摇摆等关键技术进行探析,为后续深入设计和实施提供技术支撑。

高磁场环境中铝电解车间天车轨道智能检修机器人设计与研究

高磁场环境中的铝电解车间一直是铝工业中关键的生产场所,但这种环境对设备的维护和检修带来了巨大的难度。在这些车间中,天车轨道扮演着极为重要的角色,用于移动和定位重型设备,可由于高磁场环境的特殊性质,轨道的损耗和磨损问题成为了常见难题。传统的维护方法往往昂贵且危险,因此需要一种创新的解决方案。本论文旨在介绍一种高磁场环境中的铝电解车间天车轨道智能检修机器人的设计与研究。这一机器人的研发将结合先进的材料科学、机器人技术以及自主导航算法,以实现在高磁场环境中高效、安全和经济的轨道维护。研究旨在提高车间的生产效率,减少维护成本,同时降低人员接触高磁场的风险。