A Conceptual Framework for the Forklift-to-Grid (F2G) Implementation

This paper focuses on presenting the current research findings on the “Vehicle to Grid” concept and proposes theoretical model of F2G integration in energy management of a warehouse. The study is based on an analysis of collected data and on model calculations of the economic value. Analyses of data, calculations of economic value and profitability of the proposed business model give positive results, which fully confirm the thesis that the integration of renewable energy sources and new modern technologies in the logistic processes can improve energy management.

Design of an Electric Forklift

In order to achieve integration of electrmotion and manual operation for manual forklift, this paper designs an improved manual forklift. We select the appropriate motor according to parameters of original manual forklift, which was analyzed by SolidWorks. We make the detailed design of the speed reducer according to the selected motor＇s rated speed and other parameters, and design the reduction speed ratio, reduction speed form, size of gear drive, meshing parameters, force analysis of gear and strength check. In this paper, we electrify the traditional manual forklift eventually.

Failure Analysis of Railway Forklifts and Their Current Reliability Levels

The number of forklifts ranks first among the material handling machinery in railway goods yards. It is important to analyze their failures and to assess their reliability. In this paper, the failure distribution, failure modes and laws of failure distribution of railway forklifts are analyzed based on the field data. The comprehensive assessment of the reliability level of the railway forklifts is also presented according to the reliability index system of forklifts.

Control strategy for energy recovery system in hybrid forklift

After analyzing the working condition of the conventional diesel forklift,an energy recovery system in hybrid forklift is considered and its simulation model is built.Then,the control strategy for the proposed energy recovery system is discussed,which is validated and evaluated by simulation.The simulation results show that the proposed control strategy can achieve balance of the power and keep the state of charge(SOC) of ultra capacitor in a reasonable range,and the fuel consumption can be reduced by about 20.8% compared with the conventional diesel forklift.Finally,the feasibility of the simulation results is experimentally verified based on the lifting energy recovery system.

Accuracy comparison and improvement for state of health estimation of lithium-ion battery based on random partial recharges and feature engineering

State of health(SOH)estimation of e-mobilities operated in real and dynamic conditions is essential and challenging.Most of existing estimations are based on a fixed constant current charging and discharging aging profiles,which overlooked the fact that the charging and discharging profiles are random and not complete in real application.This work investigates the influence of feature engineering on the accuracy of different machine learning(ML)-based SOH estimations acting on different recharging sub-profiles where a realistic battery mission profile is considered.Fifteen features were extracted from the battery partial recharging profiles,considering different factors such as starting voltage values,charge amount,and charging sliding windows.Then,features were selected based on a feature selection pipeline consisting of filtering and supervised ML-based subset selection.Multiple linear regression(MLR),Gaussian process regression(GPR),and support vector regression(SVR)were applied to estimate SOH,and root mean square error(RMSE)was used to evaluate and compare the estimation performance.The results showed that the feature selection pipeline can improve SOH estimation accuracy by 55.05%,2.57%,and 2.82%for MLR,GPR and SVR respectively.It was demonstrated that the estimation based on partial charging profiles with lower starting voltage,large charge,and large sliding window size is more likely to achieve higher accuracy.This work hopes to give some insights into the supervised ML-based feature engineering acting on random partial recharges on SOH estimation performance and tries to fill the gap of effective SOH estimation between theoretical study and real dynamic application.

基于主观生理评价的叉车驾驶舒适性研究

文中通过制订叉车驾驶员工作生理舒适情况调查问卷,对不同吨位叉车驾驶舒适性进行评估。结合工作肌肉骨骼疾患主观评价工具与驾驶室舒适性评价问题,采用滚雪球抽样法进行样本搜集,并运用交叉分析等方法探讨不同吨位叉车驾驶室舒适性影响因素。样本中2.0~3.8 t驾驶室舒适性相对其他吨位最佳,且随着吨位的增加高风险身体部位的患病风险也在增加,4.0~10.0 t座椅可调范围与操作杆的位置适配程度及2.0~3.8 t刹车踏板需要进行改进,1.0~1.8 t和2.0~3.8 t操作杆应选前置,右肩不适与操作杆改进设计相关。该研究为叉车制造商和设计师提供指导,为提高叉车在各行工作场所的安全性和工作质量提供了见解,对叉车人机优化具有一定的工程应用价值。

Tailpipe emission characterizations of diesel-fueled forklifts under real-world operations using a portable emission measurement system

Non-road equipment is one of the key contributing sources to air pollution.Thus,an accurate development of emission inventory from non-road equipment is imperative for air quality management,especially for equipment with a large population such as diesel-fueled forklifts.The objective of this paper is to characterize duty-cycle based emissions from diesel-fueled forklifts using a portable emission measurement system(PEMS).Three dutycycles were defined in this study,including idling,moving,and working(active duty operation)and used to characterize in-use emissions for diesel-fueled forklifts.A total of twelve diesel-fueled forklifts were selected for real-world emission measurements.Results showed that fuel-based emission factors appear to have smaller variability compared to time-based ones.For example,the time-based emission factors for CO,HC,NO,and PM 2.5 for forklifts were estimated to be 16.6-43.9,5.3-15.1,26.2-49.9,5.5-11.1 g/hr with the fuel-based emission factors being 12.1-20.3,4.1-8.3,19.1-32.4,3.5-6.5 g/kg-fuel,respectively.NO emissions appear to be the biggest concern for emissions control.Furthermore,most of the emissions factors estimated from this study are significantly different from those in both National Guideline for Emission Inventory Development for Non-Road Equipment in China and welldeveloped emission factor models such as NONROAD by US EPA.This implies that localized,preferably fuel-based emission factors should be adjusted based on real-world emission measurements in order to develop a representative emission inventory for non-road equipment.

基于ROS架构的叉车型AGV控制系统设计开发研究

针对叉车型AGV开发成本高、系统封闭、可拓展性差的问题,该文基于开源机器人操作系统(ROS),设计了一套新的控制系统。该控制系统采用双层控制架构,通过模块化的设计思想实现了控制平台的搭建。其中,上层控制器采用装有Linux操作系统和ROS的嵌入式工控机实现叉车型AGV的即时定位与建图(SLAM)及路径跟踪功能;下层控制器采用西门子PLC实现对I/O信号的采集,以及通过CAN网络实现对舵轮的行走与转向控制及信息采集、对电源系统实现监控、对货叉起升高度检测,同时可以与车间调度计算机通过无线网络进行AGV调度与在线监控。

基于功率分配的混合动力叉车系统及控制策略研究

叉车作业是物料搬运领域的重要环节。近年来,内燃叉车的排放要求不断升级,为实现节能减排、降低燃油消耗的目标,同时满足多班制连续性作业场景的需求,提出一种基于功率分配的混合动力叉车系统及其控制方案。通过对行走系统采用内燃机与电动机动力耦合的方式,解决了传统内燃叉车在爬坡、重载起升等工况的大扭矩需求,同时避免了在平地运行、小负载起升时因实际有用功需求不多而导致的内燃机无用功的消耗,从而在本质上提高系统的有用功占比,达到节约能源的目的。通过实际应用测试,所提出的混合动力叉车系统的节油率可以达到30%以上。

电动叉车起升调速机构设计及可靠性试验方法研究

电动叉车起升功能的基本原理为驾驶人员操作起升阀杆时,阀杆连接着多路阀阀芯,阀杆行程的变化会引起多路阀阀芯运动,从而引起起升阀口的开合度变化。阀口的开合度直接影响液压油流入起升油缸的流量,从而影响起升速度。此外,多路阀上安装有起升调速传感器。阀杆行程的变化会触发起升调速传感器产生连续变化的信号并输出给电机控制器,电机控制器根据接收的信号控制油泵电机转动。油泵电机连接并带动齿轮泵工作,将液压油以不同的流量传递至多路阀起升阀口,并最终传输至起升油缸,从而影响起升的速度。基于此,对起升调速机构的试验方法进行研究,并开展可靠性试验验证,保障起升调速机构的可靠性,促进研究方案的应用。

叉车转向系统动力学建模仿真及转向性能研究

平衡重式叉车是一种专门设计用以装卸搬运的工业车辆,在港口码头等运输行业的应用非常广泛。目前,由于叉车的运行工况环境复杂,且工作过程需要频繁进行转向操作,叉车的转向系统性能和运行稳定性愈发受到关注。文中为提升平衡重式叉车转向性能,以某4 t平衡重式叉车为研究对象,建立了基于主动后轮转向的滑膜控制系统仿真模型,研究其对叉车在不同工况条件下转向系统性能的影响并进行评价。

叉车球墨铸铁转向节在DISA线上的开发生产

主要介绍了球墨铸铁叉车转向节铸件的技术要求及在DISA线的生产工艺。针对工艺开发过程中遇到的冒口颈缩孔、铸件砂孔、本体试棒性能不合格等问题,通过分析铸造工艺,提出了相应的解决方案。通过采用底注式浇注系统和顶部球型冒口补缩,改进热砂芯的芯头结构,熔炼时加入Cu、Cr等合金元素,采用转运包内一次孕育及在浇注时二次随流孕育强化孕育等措施,成功地在DISA线上生产出了高性能的叉车转向节类铸件。

一种放射性环境下的叉取装置设计

文中基于放射性物料在手套箱与转运通道之间运输方式现状的分析,开展了放射性物料转运装置的技术研究,旨在提高物料转运效率,规避操作人员受辐射伤害。通过分析使用需求确立了研制方向,对装置的结构原理、关键部件受力和性能要求进行了设计,并对关键部件进行了模块化、耐辐照设计,最终确定了装置设计方案。通过首检运行考核试验,重点验证了装置长期运行重复定位精度和连续运行丝杠螺母温升问题。根据试验结果,对装置存在的问题进行了优化整改及验证。该装置的成功研制和验证,为后续工艺过程的自动控制和远程化操作提供了技术支撑。

供配电设备制造企业设备安全隐患排查治理的研究及应用

设备是制造企业生产的核心,若存在安全隐患,可能导致事故、人员伤亡或财产损失。因此,周期性的设备安全隐患排查至关重要,可防患于未然,保护员工安全和生产顺畅。为保证员工安全、提高生产效率和质量、降低企业风险和成本。本文以叉车设备为例,利用FMEA方法,结合熵权法确定隐患排查的频次,建立针对企业叉车设备的安全隐患排查标准知识库,从而为企业设备提供了一套有效的安全隐患排查和治理标准。此外,本研究还明确了隐患排查的责任分配和治理要求,确保了设备安全管理措施的实施效率和有效性。

基于高分辨率工业CT的场(厂)内机动车用进水锂电池检测研究

近年来,随着动力电池技术的不断发展,越来越多的厂家青睐采用锂电池作为场(厂)内机动车动力源。然而,对场(厂)内机动车用锂电池的安全性能检测一直缺乏相关研究,特别是对故障电池的无损检测,鲜有开展。为此,本文采用高分辨率工业CT对场(厂)内机动车用故障锂电池进行研究,扫描内部结构,并结合充放电情况分析锂电池性能衰减与内部结构之间的关系,为场(厂)内机动车用锂电池无损检测提供解决方案。

某桁架机械手结构设计与刚度分析

桁架机械手是自动焊接生产线的重要组成部分,为了满足某企业叉车门架自动焊接生产线大跨度、高载重、精度高的要求,设计开发出一款有效行程长为36 m、宽为9.76 m的桁架机械手,其最大载重1.5 t。为了确保其结构性能要求,利用有限元分析工具,验证其最大变形量小于2 mm,结构刚度和强度都满足设计要求;同时桁架机械手制造出来后,经过现场装机测试验证,整体性能指标满足用户需求。

国四叉车实际作业排放分析研究

本文基于三台国四排放水平的叉车,研究其在实际作业中的工况及排放特性,结果表明:三台国四叉车均满足国四排放法规,其中PN的平均比排放更是达到了国六重型柴油车PN排放水平。冷启动阶段的PN平均比排放高于有效工作事件数据和原始数据。叉车在冷启动阶段如采用较低的负荷进行作业,会使其CO_(2)和NO_(X)平均比排放高于有效工作事件数据和原始数据。有效工作事件数据的NO_(X)、CO、CO_(2)平均比排放略低于或等于原始数据。叉车的PN平均比排放随作业负载的增加呈现上升的趋势,叉车移动速度、载荷升降速度、载荷质量大小均为影响功率及排放的因素。

面向铁路应急物资仓储的叉车式AGV路径规划研究

针对当前智能化物资仓储环境中叉车式AGV路径最优规划问题,在对常见三种路径规划优化算法分析讨论的基础上,选择A算法作为面向智能化物资仓储环境的叉车式AGV路径规划方法,并采用曼哈顿距离模型作为启发函数,提高仓储环境下最优路径的搜索效率。结合某铁路物资仓库实际场景,构建真实地图并进行路径规划仿真实验,结果表明A算法在路径搜索速度和工作效率等方面均明显优于其余两种算法,能够更加有效地规划出较短的运行路径,为物资仓储环境下智能无人化仓库建设提供了技术参考。

内燃柴油叉车柴油机颗粒物滤清器DPF的研究

本文主要研究安装在柴油内燃叉车排气系统中,通过过滤来降低排气中颗粒物(PM)的装置—柴油机颗粒物滤清器系统(Diesel Particulate Filter,后简称DPF)。DPF技术中国是从上个世纪80年代开始组织进行研究,2012年开始对于DPF的材质和DPF的再生问题有了一定的成果,2016年4月1日全面实施国Ⅲ标准后更是推动其大步前进,中国知名叉车企业也纷纷开始开发配置带DPF康明斯发动机的内燃柴油叉车。随着2022年有实施的国Ⅳ标准,DPF技术在中国的大规模商用已具备成熟的市场,因此从叉车颗粒物的排放、DPF技术和其发展、DPF系统的拆装和改装来进行叉车柴油机颗粒物滤清器DPF研究。

基于AMESim的叉车液压提升系统仿真分析

为了解决电动叉车货叉持重时液压缸回缩速度过快而产生较大冲击,容易损伤缸体和管路以及货叉持重量不同时液压缸伸出速度不可控的问题,优化了电动叉车液压提升系统,并进行仿真验证。根据设计手册设计液压提升系统,初选系统工作压力为16 MPa,在液压泵的出油路上连接蓄能器来吸收流量脉动,在液压缸无杆腔进油路配置调速阀,实现了对不同持重量的压力补偿,使抬升速度可控,在无杆腔回油路上配置顺序阀,为液压缸活塞杆在承载回缩时提供给背压,避免活塞杆自由下落损伤液压缸;对液压元件进行了设计选型,选用CBG2100-BF100液压泵、HSGL-100/70E-231-3000×3280液压缸、3WE10E31B/CG24N9Z4电磁换向阀、RVP30-10B单向阀、DBDS30P10B顺序阀和THF-G10调速阀;应用功率键和图的原理对液压系统进行研究,使用数字仿真法研究液压系统的动态特性,通过仿真软件AMESim搭建液压系统数学模型,并对设置关键元件参数进行仿真。仿真结果表明,优化后液压系统的液压缸活塞杆完全缩回用时8 s,无振荡,运行稳定,液压缸活塞杆缩回时油口流量为87 L/min,液压泵产生的流量脉动被蓄能器吸收,系统运行稳定,符合设计要求,液压提升系统理论上可行、可靠。