多载具自动化存取系统货位分配优化

根据多载具自动化存取系统运行的特点,统筹考虑存货货位和取货货位分配两方面内容,建立了多载具自动化存取系统货位分配优化的通用模型.该模型以最小化指令周期内存取货物的行程时间为优化目标,适应于不同载具数量和货化规模情形下的货位优化.设计了一种结合启发式算法的混合遗传算法来求解这一非确定多项式完全问题,并通过算例验证了该算法的有效性.     

基于两阶段狼群算法的自动化立体仓库作业集成优化

为提高单载具自动化立体仓库动态工况下的进出库效率,针对自动化立体仓库作业集成优化问题建立了仿真优化模型。模型根据货物重质、出入库频率划分货架区域,以指令内最小化单载具堆垛机运行时间为研究目标,设计了一种两阶段狼群算法对其进行优化。该算法使用狼群算法对货位分配和作业调度进行集成优化,求解过程体现出两优化问题之间的关联和反馈。实验结果表明,在不同的订单规模下,相比其他优化方式,两阶段狼群算法能得到满意解,并有效缩短自动化立体仓库的作业时间。     

双载式多层穿梭车仓储系统复合作业路径优化

为提高自动化立体仓库的运作效率,提出混合植物繁殖算法,有效地解决了双载式多层穿梭车仓储系统复合作业路径优化问题。分析了提升机和穿梭车在系统中的实际调度路径,并考虑了其运动过程中的加减速度特性建立相应的数学模型。针对该系统复合作业的特点,设计结合交叉变异算子的混合植物繁殖算法对该模型进行优化求解,将算法中的固定边界复杂交换转换为固定边界的随机乱序排列,避免算法过早收敛陷入局部最优,以此提高算法性能。通过实例分析表明,与遗传算法和基本植物繁殖算法相比,混合植物繁殖算法的运算速度更快、优化效率更高,能够有效地缩短双载式多层穿梭车仓储系统复合作业时间,提高进出库调度效率。     

多载具自动化立体仓库货位分配与作业调度集成优化

为提高多载具自动化立体仓库进出库作业效率,提出货位分配与作业调度集成优化方法。从指令分组、货位分配及子行程作业模式与顺序3方面进行分析,结合堆垛机实际运作规律,构建以最小化行程时间为目标函数的集成优化数学模型。针对二者相互反馈的特点,设计了双层遗传搜索算法对模型进行求解,该算法使优化形成一个闭环,可得到比较理想的解。仿真实验结果表明,双层遗传算法在不同的订单规模和载具数量下均能获得满意解;与分别优化相比,所提方法能够有效缩短作业时间。     

子母式穿梭车仓储系统复合作业路径优化

针对子母式穿梭车仓储系统复合作业路径优化问题,分析了两套子母车配一台升降机在一次存取货作业中的3种不同作业方式,以存取货作业时间最短为目标建立了进出库复合作业调度模型。设计结合交叉变异算子的自适应粒子群算法对该模型进行路径优化求解,并对两套子母穿梭车进行合理调度。仿真结果表明,该调度模型针对子母式穿梭车仓储系统复合作业具有较高的准确性,升降机与子母穿梭车以1∶2的配比方式在不同订单规模下能够更经济有效地缩短仓储系统的进出库复合作业时间,提高作业效率。     

多目标下的自动化立体仓库拣选作业路径优化

自动化立体仓库系统是在计算机直接控制和管理下自动存取并实现综合自动化管理货物的多层仓库存储系统,其中,堆垛机作业时间长短直接影响仓库存储效率的高低.针对堆垛机拣选作业模式,提出了自动化立体仓库拣选作业的新型数学模型,并对遗传算法初始种群进行改进,用改进后的遗传算法对该模型进行了求解.     

基于改进遗传算法的环形RGV系统调度优化

针对自动化立体仓库中环形穿梭车系统(Rail Guided Vehicle system,RGVs)调度优化问题,综合考虑RGV数量、进出货口限制、复合作业次数和堵塞次数对作业效率的影响,以最小化任务总完工时间为目标,建立了多影响因素下的RGV调度数学模型,并采用改进遗传算法对模型进行求解。首先,设计了多影响因素下的编码方式,提高算法求解实际问题的能力;然后,在遗传算法中引入模拟退火操作,提高算法的局部搜索能力,避免算法求解过程陷入局部最优;最后,设计染色体修复方法来避免非法解的出现,提高算法的收敛速度和求解稳定性。通过实例验证了模型和算法的有效性与先进性。     

大规模作业车间多瓶颈调度算法

针对大规模作业车间调度问题,提出一种基于滚动窗分解的多瓶颈调度算法.该算法基于关键路径法进行多瓶颈机器的识别,沿时域将大规模调度问题分解为多个子问题进行求解.在子问题创建过程中,提出负荷均衡分布的规则,使得各工件在各子问题中的负荷均匀分布,以实现算法求解过程的稳定性;在子问题的求解过程中,遵循约束理论中瓶颈机主导非瓶颈机的原则,采用瓶颈工序最优化调度、非瓶颈工序采用分派规则快速调度的调度策略,提高算法的求解效率;通过相邻子问题间的工序衔接再优化过程,以及全局解评价子问题染色体适应度值策略,有效避免了子问题分解创建和求解过程的局限性,提高了算法的求解质量.仿真结果表明,该算法具有较佳的求解效率和质量.     

基于效率函数的双资源约束作业车间调度算法

目前对制造业领域作业车间调度问题研究中,仅考虑单一设备资源的传统作业车间调度问题已不能反应出实际作业车间的作业环境。根据实际作业车间多资源环境,建立了分别最小化生产完工期和超期时数为目标函数的设备和模具双资源约束作业车间调度模型,并采用基于效率函数的逆序调度算法对问题进行求解。最后,通过实例对算法进行验证并给出对比结果。     

基于改进灰狼优化算法的自动化立体仓库作业能量优化调度

针对带有截止时间约束的自动化立体仓库出入库作业调度问题,以调度过程中堆垛机能量消耗为优化目标建立数学模型,并引入相应的惩罚函数。对于入库货物,同时考虑定位存储和随机存储两种入库策略,采用一种最近邻货位选择策略对随机存储货物进行合理货位分配。采用一种改进灰狼优化算法对问题进行求解,算法通过引入融合Lévy飞行的混合个体更新策略和多种群重组策略来增强算法的搜索能力。通过仿真实验验证了改进灰狼优化算法在求解自动化立体仓库出入库作业能量优化调度问题的有效性。     

On the Relation of Load to Average Gap in the Contact Between Surfaces with Longitudinal Roughness

A computer simulation model for the contact between longitudinally-oriented rough surfaces has been formulated. This model closely duplicates the actual surf ace contact deformation behavior by taking into account the elastic interactions between the asperities. There were no assumptions made about the shapes, or any deformation behavior of the asperities, except for their obeying the laws of elasticity. The plastic deformations on the high asperity peaks were taken into account by setting a ceiling on their contact pressures at the material hardness value. The simulations used real surface profiles which were digitized from unworn circumferentially ground steel surfaces. Each pair of these profiles was mathematically combined to form an equivalent rough profile pressing against an infinitely rigid flat and having the appropriately adjusted elastic modulus. A total of 28 different pairs of profiles were used in the simulations. Each contacting pair was subjected to 30 different load levels and the local contact pressures and deformations were calculated. The contact simulations yielded some important mathematical relationships between parameters, such as the real area of contact, average gap, and average asperity load through statistical curve fitting. Two analytical functions were generated to relate the average load to average gap and the real area of contact to load.     

三绕组变压器的双绕组等效建模及在Matpower中的应用

针对实际电网存在着大量的三绕组变压器,但国际上一些著名商业软件,如BPA仿真软件、Matpower这一权威潮流计算开源软件,均只提供双绕组变压器模型,限制了其在具有三绕组变压器的电力系统中的应用的问题,潮流计算是自主开发的电力系统各种应用软件的核心模块,因此依托国际权威开源程序进行二次开发,是一种较好的选择。对Matpower要求的数据格式进行了归纳,对变压器的一般的等值电路及带理想变压器的等值电路和带标幺值的等值电路进行了分析研究,提出了三绕组变压器转换为双绕组等效模型的建模方法,使得原先只适应双绕组变压器的潮流计算软件可以适用于三绕组变压器电网的潮流计算;最后以Matpower软件为例进行了案例计算,并用PSASP仿真软件进行对比验证。研究结果证明,所提出的建模方法是有效的。     

电站锅炉模糊风险评价方法研究与应用

针对电站锅炉风险等级评价问题,将模糊综合评价技术应用到电站锅炉风险等级评价中。开展了电站锅炉失效影响因素及模糊评价因素的重要程度分析,建立了一套科学合理适于在线评价的电站锅炉风险评价体系,提出了模糊综合评价技术与改进的模糊层次分析法相结合的模糊风险评价方法,利用改进的模糊层次分析法计算了指标体系中各层指标权重。对某一台电站锅炉的实际运行工况影响子因素进行了模糊风险评价,采用模糊合成算子进行模糊综合运算得到电了站锅炉运行工况影响子因素的评价向量。研究结果表明:电站锅炉的运行工况影响子因素的风险评价等级为第6级,失效可能性等级为小,该电站锅炉运行工况良好。     

交通荷载作用下桥梁结构参数识别方法

应用动力节点加载法,将作用在桥梁上的交通荷载转化为等效节点荷载,再用两步构造法识别结构物理参数.第1步,用Newmark-β方法变换结构运动方程,并用结构的加速度响应求得变换空间内的位移、速度和加速度响应;第2步,基于最小二乘原理,构造出变换空间内求解结构参数的递推式,进行结构物理参数识别.数值模拟结果表明,在交通荷载作用下,该方法能够快速、准确地进行桥梁结构参数识别.     

Quantum Cooperative Robotics and Autonomy

The intersection of Quantum Technologies and Robotics Autonomy is explored in the present paper.The two areas are brought together in establishing an interdisci...     

考虑进油孔有限长滑动轴承油膜力的近似解析解

针对具有进油孔的有限长滑动轴承油膜力求解问题,采用变分原理和分离变量法,求得了有限长滑动轴承油膜压力分布的近似解析表达式。将油膜压力分布的近似解析表达式在油膜存在区域上进行积分,即得到了油膜力。将提出的计算有限长滑动轴承油膜力方法与无限长轴承模型、有限元方法的计算结果进行了比较,发现了提出的方法与有限元方法的计算结果很接近。最后,研究了进油孔位置和进油压力对油膜存在区域、油膜力等的影响,研究结果表明进油孔位置和进油压力对油膜存在区域和油膜力有较大的影响。     

RLS and LMS blind adaptive multi-user detection method and comparison in acoustic communication

RLS and LMS blind adaptive multi-user detection algorithm and multi-user detector was proposed to solve the problem of multi-user signal detection problem encountered in underwater acoustic communication networks.In simulation analysis,RLS and the LMS blind adaptive multi-user detector were designed and tested for synchronous and asynchronous multi-user communication process.The results of SIR comparison and MMSE comparison show that,both of the two methods can realize blind adaptive detection when any user change in multi-user communication,during this process,the training communication sequences are not needed.The RLS algorithm has about 5 dB higher in SIR compared with LMS algorithm,and the convergence velocity of RLS algorithm is also higher than LMS algorithm when the communication users change.RLS algorithm has better ability in multi-user detection than that of LMS algorithm,and it has great attraction and guiding significance for solving the problem of multiple access interference(MAI) in multi-user communication.     

Robust Impedance Control of Robots Using an Adaptive Interaction Force Observer

For robot interaction control,the interaction force between the robot and the manipulated object or environment should be monitored.Impedance control is a type ...     

Research on key techniques of expendable conductivity temperature depth measuring system

This paper analysis the developing of expendable conductivity temperature depth measuring system(XCTD)and introduce its principle of measuring about temperature,salinity and depth of ocean.Some key techniques are put forward.According to the real needs of XCTD,conductivity sensor with high sensitivity is designed by principle of electromagnetic induce,the ocean conductivity from induced electromotive force has been calculated.Adding temperature correction circuit would help to reduce error of conductivity measurement because of sharply changing temperature.Advanced temperature measuring circuit of high precision and the constant current source is used to weaken effect of self-heating of resistance and fluctuation of the source.On respect of remote data transmission,LVDS is a good choice for the purpose of guarantee the quality of data transmitted and the transmission distance is reaching to thousand meters in the seawater.Modular programming method is also brought into this research aimed at improve the stability,reliability and maintainability of the whole measuring system.In February,2015,the trials in South China Sea demonstrate that the developed XCTD realize effective measurement at a speed of 6 knots and detection depth at 800 m.The consistency coefficient of the acquired data is greater than 0.99 and the success rate of probe launching is above 90%.     

CHARACTERISTCS OF FLUID FILM IN OPTIMIZED SPIRAL GROOVE MECHANICAL SEAL

In order to investigate the sealing performance variation resulted from the thermal deformation of the end faces, the equations to calculate the fluid film pressure distribution, the bearing force and the leakage rate are derived, for the fluid film both in parallel gap and in wedgy gap. The geometrical parameters of the sealing members are optimized by means of heat transfer analysis and complex method. The analysis results indicate that the shallow spiral grooves can generate hydrodynamic pressure while the rotating ring rotates and the bearing force of the fluid film in spiral groove end faces is much larger than that in the flat end faces. The deformation increases the bearing force of the fluid film in flat end faces, but it decreases the hydrodynamic pressure of the fluid film in spiral groove end faces. The gap dimensions which determine the characteristics of the fluid film is obtained by coupling analysis of the frictional heat and the thermal deformation in consideration of the equilibrium condition of the bearing force and the closing force. For different gap dimensions, the relationship between the closing force and the leakage rate is also investigated, based on which the leakage rate can be controlled by adjusting the closing force.