水电站斜拉门机小车液压驱动机构研究

水电站双向门式启闭机的小车液压驱动机构的设计关键,是保持驱动小车的两侧液压缸同步运行,并采取措施防止活塞杆产生挠度和弯扭变形.液压管路对称布置,减少了管路对双缸同步的影响;液压系统采用“调速阀+旁路泄油纠偏回路”同步控制方式;关节轴承和滑动轴承组合采用铰接结构和抗挠托架,实现了液压缸对外界产生的挠、弯、扭作用的自适应.工程实践证明:小车液压驱动机构运行平稳、同步控制准确、无啃轨现象,满足实际工况需要.     

大型全回转浮式起重机平衡系统优化数学模型

针对大型全回转浮式起重机的结构和工况特点,在满足抗倾覆稳定性要求下,将浮式起重机自重产生的不平衡力矩与起升货物产生的不平衡力矩之和的均方根力矩作为目标函数值,建立以平衡系统主要构件强度、刚度、结构尺寸和回转轮压合理性为约束条件的多目标设计优化数学模型,运用遗传算法优化浮式起重机平衡系统,最终得出优化数据.该数学模型在具体优化过程中取得较为满意的优化结果,为大型全回转浮式起重机的设计优化提供有效方法.     

基于蚁群算法的集装箱堆场起重机优化调度

集装箱堆场起重机(场桥)优化调度是在确定场桥配置数量的基础上,对场桥进行任务分派,使得场桥的行走时间最短。通过动态地调整信息素更新方式、限制信息表的范围来克服蚁群算法容易停滞的缺点。利用改进的蚁群算法对场桥的任务调度问题进行了探讨,并实现了求解。仿真结果表明,蚁群算法求解场桥调度问题时,得到了较好的结果,提高了场桥的工作效率。     

A fast heuristic for quay crane scheduling with interference constraints

This paper considers the problem of scheduling quay cranes which are used at sea port container terminals to load and unload containers. This problem is studied intensively in a recent stream of research but still lacks a correct treatment of crane interference constraints. We present a revised optimization model for the scheduling of quay cranes and propose a heuristic solution procedure. At its core a Branch-and-Bound algorithm is applied for searching a subset of above average quality schedules. The heuristic takes advantage from efficient criteria for branching and bounding the search with respect to the impact of crane interference. Although the used techniques are quite standard, the new heuristic produces much better solutions in considerably shorter run times than all algorithms known from the literature.     

并行通讯格雷码多圈旋转编码器和S7-200型PLC在石灰炉提升机上的应用

本文系统分析了各种旋转编码器和S7-200型PLC的特点,解决了用S7-200型PLC将格雷码翻译成二进制码等难题,选用并行通讯格雷码旋转编码器、S7-200型PLC和中文TD200人机界面组成控制系统,成功实现石灰炉提升机自动控制,控制系统必将在小规模精度定位领域中得到广泛应用。     

双循环策略下岸桥与跨运车的联合调度

集装箱码头采用跨运车能够减少作业环节和码头机械设备的种类与数量,同时缓存区容量的设置至关重要。首先,为降低码头总完工时间、提高码头作业效率,并解决采用跨运车作为水平运输设备与岸桥进行联合装卸作业时产生的时空协调问题,引入了双循环操作策略,对岸桥与跨运车的联合作业序列优化问题进行研究。其次,建立以总完工时间最小化为目标,考虑岸桥与跨运车双循环操作的实际约束、岸桥缓存区容量限制、安全时间等约束的混合整数规划模型。然后,针对传统禁忌搜索（TS）算法的局限性,加入贪婪算法、多种邻域搜索方式、响应性策略,设计了基于贪婪算法的响应性TS算法,并进行了数值实验。实验结果验证了所提模型与算法的有效性。最后,通过对缓存区容量与跨运车数量、岸桥与跨运车配比的实验分析,得出了最优的跨运车数量和缓存区容量、岸桥与跨运车配比。结果表明：与传统码头设备配置相比,双循环策略可减少跨运车使用数量,提高岸桥与跨运车使用率。     

Integrated mathematical optimisation approach for the tower crane hook routing problem to satisfy material demand requests on-site

Optimising decisions around the location and operation of tower cranes can improve the workflow in construction projects. Traditionally, the location and allocation problems involved in tower crane operations in the literature have been solved separately from the assignment of material supply points to demand points and the scheduling of the crane’s activity sequence across supply and demand points on a construction site. To address the gap, this paper proposes a binary integer programming problem, where location of the tower crane, allocation of supply points to material-demanding regions, and routing of hook of the crane based on activity sequencing of the hook across supply and material-demanding regions on site are optimised. The novelty in this work is in the way the crane’s activity scheduling is modelled via mathematical programming, based on routing the hook movement to meet material demand, through minimising tower crane operating costs. A realistic case study is solved to assess the validity of the model. The model is contrasted with results obtained from other solving algorithms commonly adopted in the literature, along with a solution proposed by an experienced practitioner. Results indicate that all instances can be solved when compared to other meta-heuristics that fail to achieve an optimum solution. Compared to the solution proposed by the practitioner, the results of the proposed model achieve a 46% improvement in objective function value. Planners should optimise decisions related to the location of the crane, the crane’s hook movement to meet service requests, and supply points’ locations and assignment to material-demanding regions simultaneously for effective crane operations.     

吊车钢丝绳非线性谐振建模及消谐控制

对于欠驱动吊车而言, 已有的方法都只考虑如何消除摆角. 然而当钢丝绳的摆角很小时, 钢丝绳上可能仍 然会存在严重的谐振. 针对吊车的消谐问题, 本文率先提出了一种基于钢丝绳–电机轴的非线性谐振力矩模型. 具体而言, 先利用振动力学的方法, 建立了非线性谐振力矩模型, 该模型可以将钢丝绳上的非线性谐振力矩归算到电机轴上, 然后通过电机控制器调节电机的输出力矩, 使得电机输出的基波主力矩上叠加一个大小相等方向相反的非线 性谐振力矩, 以达到消除钢丝绳上的谐振力矩的目的. 最后通过Simulink仿真和实验证明该方法具有良好的控制性 能, 不仅可以有效消除钢丝绳上的谐振, 并且能进一步减小摆角.     

双伸位堆垛机系统调度的优化设计

以某机务段段修配件自动化立体仓库(AS/RS)为例,通过分析影响双伸位堆垛机系统运作的重要因素,提出一种基于作业时间最短的优化设计,建立相应的数学模型,并采用分区平均搜索初始种群的遗传算法对其进行验证。结果证明该优化设计有利于提高双伸位堆垛机AS/RS系统的运作效率。     

桥式起重机精准定位在线轨迹规划方法设计及应用

针对工业桥式起重机的异步电机难以准确跟踪给定轨迹,从而导致离线轨迹规划算法定位误差很大的问题,论文提出一种基于相平面分析的在线轨迹规划算法.这种方法利用激光测距仪采集位置信息,在起重机运行过程中,根据台车与目标位置的距离来优化轨迹不同阶段的运行时间,并实时调整台车轨迹的有关参数,以实现台车精准定位的目标.实验结果表明,这种方法可以很好地兼顾负载快速消摆与台车准确定位两方面的要求,有利于提升桥式起重机的运送效率.论文将这种在线轨迹规划方法成功应用于标准32 t工业桥式起重机,并取得了良好的运行效果.