Lift Truck Research Articles

Frontal Crash Testing of a Class V Lift Truck

Abstract Counterbalanced, center control, high-lift trucks with a sit-down, non-elevating operator position are required to have a restraint system. The restraint system is intended to restrain the operator in the normal operating position and assist in reducing the risk of entrapment of the operator between the truck and the ground in the event of a tip-over. This is typically accomplished through the use of a two-point lap belt. This type of restraint also provides a degree of protection in the event of a collision between the lift truck and another object. Lift trucks operate in relatively low-speed environments, and many are limited to a maximum speed of 8 mph through a limiting device or by job site regulations. Though the speeds are low, lift trucks can operate in close proximity to other lift trucks and stationary rigid structures, creating the potential for collisions. The standards governing lift truck restraints do not mandate impact testing or injury criteria. This paper describes instrumented frontal impact and sled testing with a peak acceleration of 51 g performed on a Class V lift truck using an anthropomorphic test device (ATD) to test the effectiveness of lift truck restraints in this scenario. The results of this testing showed ATD injury metrics within automotive safety standards.

УДОСКОНАЛЕННЯ ІСНУЮЧИХ МЕТОДІВ ОЦІНЮВАННЯ ФУНКЦІОНУВАННЯ АЕРОПОРТІВ ПРИ МІЖНАРОДНІЙ ІНТЕГРАЦІЇ

The article is devoted to the study of methods for assessing the operation of airports under international integration and their improvement. The recent scientific studies on assessing the operation of international airports were analyzed and it was found that the most actively used methods are the initial data envelopment analysis (DEA) and various variants of quantile regression, Tobit regression, assurance region methods, SBI and DMU, Malmquist index, classification and regression tree, bootstrapping tool and other tools. It was confirmed that the existing methods for assessing the airports’ operation have a significant number of indicators for calculations based on the evaluation of economic, technical or overall efficiency. The parametric methods for assessing the operation of airports, their advantages and disadvantages were characterized. The methodology of stochastic frontier analysis (SFA), the use of a non-parametric approach to evaluate airport performance, and the evaluation of the overall efficiency of two-stage DMUs with shared resources were described. The methodical approaches based on the use of the spatial regression model, the AAG model and the stochastic frontier model were characterized. The methodology for determining the target function Effi to assess the efficiency of each airport DMUi was described. The scheme for assessing the airports’ operation by input and output indicators was proposed, which includes a three-module assessment system for the passenger, cargo and joint modules. The cargo module is the authors’ own development and its creation is justified by the fact that a significant number of air cargo flows are served by passenger aircraft. The group of input indicators of the cargo module includes the length of the loading and unloading work front, the number of cargo receiving points, the working area of rack and stack storage, the number of electric forklifts and lift trucks, as well as the number of cargo warehouses, and the number of general and special categories of cargo are defined as output indicators.

Real-Time Helmetless Detection System for Lift Truck Operators Based on Improved YOLOv5s

Real-Time Helmetless Detection System for Lift Truck Operators Based on Improved YOLOv5s

ANALYSIS OF STRENGTH OF A FORK OF THE FORKLIFT BY NUMERICAL METHODS

Forklift is an industrial power truck, commonly called forklifts or lift trucks, then usually have two forks the can be trial power truck used forklifting and transport materials. Fork-lifts, to this day, the fork strength of a forklift under load still seems to be one of the biggest issues. Fork’s related structural design and detail have a significant impact on the overall performance and reliability of a forklift. In this work, static analyses of a fork forklift were performed using Finite Element Method, on the free software FreeCAD, a multidisciplinary software application that is the result of a long-term active collaboration between develop-ers and users. Open science hardware is cheaper, easier to maintain, and more accessible to more people. In this paper, by calculating the maximum normal stress of the section, the force situation and allowable stress of the fork are analyzed. The fork is made of structural material is 40Cr steel. The output values of the static study consist in establishing the distri-bution of equivalent unitary stresses (stress state) according to the von Mises criterion. The maximum stress of the structure is 128 MPa, which is does not exceed the allowable. Then in order to enhance the structural strength of the weak part, the measures of gradually in-creasing the fillet radius of the fork root were proposed, and the radius were selected as 35mm and 45mm, the weight of the forklift load was still 0,5t. Numerical experiments have shown that by increasing the radius from 25 to 45 mm, stresses decrease by 1.1...1.15 times, which is consistent with the theory of basic mechanics that stress concentration can easily lead to fatigue failure of the structure. Both numerical calculations and visual analysis showed consistency, with stress concentrations observed at the fork neck, demonstrating the accuracy of the established finite element model.

Case Study: Successful Application of a Novel Gas Lift Valve in Low Pressure Wells in Fuling Shale Gas Field

The Fuling shale gas field is facing a rapid gas production decline due to heavy liquid loading issues. Given the condition that most wells are located at remote areas in the mountains, the traditional gas lift methods that require either fixed compressor or skid-mounted gas lift trucks do not seem feasible and occur high operation costs. A new type of gas lift valve that can be opened or closed at a low valve dome pressure indicates the high sensitivity to low production pressure. Thus, the piping line pressure can be utilized to activate the valve due to its new advantages. In addition, the specially designed structure of the gas lift valve can be activated via pressure increases in the tubing to create a channel between the tubing and annulus. The valve that previously functioned as a dummy valve was then switched to a gas lift valve. Field application results show that all wells were successfully restarted by only utilizing the low piping pressure, and loaded liquid was lifted with gas production at an incremental rate that reached up to 27.4 × 10 kscm/d per well. Fewer slickline operations were conducted to replace the dummy valve. The result of the application shows that the new type of gas lift system has a wide range of application prospect for low pressure wells, especially for shale gas wells.

International Specialized Exhibition of Internal Logistics LogiMAT 2022 in Germany

International exhibition of internal logistics was held in Stuttgart (Germany) after a two-year break due to COVID-19 pandemic. The exhibition was a representative review of innovations in logistics and identified future developmental trends for this most important sphere of economics. Digitalization and automation dominated the exhibition with participation of about 1,500 companies. Exhibits reflecting the digitalization of logistic supply networks attracted the greatest interest in the section of digitalization and new information technologies. The displayed software products ensure high-level digitalization of supply chains. New transportation and storage systems and new technologies for picking orders were put on display at the exhibition. New types of hoisting & handling and storage equipment were widely exhibited, for example, electric fork lift trucks, stacker cranes, grabbing devices, etc.

Evaluation of the Effect of a Rear Operator Guard on the Overall Safety for Operators of Standup Lift Trucks

Abstract Standup high lift trucks have an open operator compartment designed to allow for easy egress from the truck in the event of an off-dock, off-trailer, or tip-over accident. The open compartment design also protects the operator during nontip-over collision accidents, provided the operator maintains him or herself within the compartment before impact. However, it has been suggested that an additional rear operator guard would better protect operators during nontip-over collision accidents. This study aimed to investigate operator injury potential and kinematics during off-dock and off-trailer accidents where the presence of a rear operator guard prevents the operator from exiting the truck and to evaluate the potential for an operator to restrain him or herself within the operator compartment of a standup lift truck during an off-dock or off-trailer accident. An instrumented anthropomorphic test device (ATD) was subjected to a series of off-dock accidents and a single off-trailer accident utilizing three different standup lift trucks. The kinematics and loads experienced by the ATD were quantified and correlated to human injury potential. Additionally, this study examined the potential for a rear operator guard to impede operator egress during an off-dock or off-trailer accident. Testing demonstrated the potential for serious or greater injury to an operator subjected to an off-dock or off-trailer accident. The authors conclude that a rear guard would negatively impact the overall safety of a standup lift truck in most working environments.

Prediction of Accident Occurrence Possibilityby Fuzzy Rule-Based and Multi-Variable Regression (Case Study: Lift Trucks)

Uncertain and stochastic conditions of accidents could affect the risk and complexity of decisions for managers. Accident prediction methods could be helpful to confront these challenges. Fuzzy inference systems (FIS) have developed a new attitude in this field in recent years. As lift truck accidents are one of the main challenges that industries face worldwide, this paper focuses on predicting the possibility of these types of accidents. At first, the data collection is done by using interviews, questionnaires, and surveys. A FIS approach is proposed to predict the possibility of lift truck accidents in industrial plants. Furthermore, our approach is validated using data from many real cases. The results are approved by the multivariate logistic regression method. Finally, the output of the fuzzy and logit models is compared with each other. The re-validation of the fuzzy control model and high consistent of the output of these two models is presented.

A Novel Integrated Approach to Solve Industrial Ground Floor Design Problems

The ground floors of buildings usually have high loads from racks and other storage equipment in industrial buildings and logistics centers. Such types of buildings commonly require lift trucks. Therefore, there are special requirements for flatness tolerance across and along the driving track of truck lifts. Structural design solutions must be optimized and sustainable. The article reviews the behavior of soils and the importance of the actual behavior assessment of soils during the design of the ground floor on the elastic subgrade. The behavior of the ground floor’s areas above pile foundations that support the building’s columns is essential. Calculation results show the impact of subgrade stiffness on the behavior of reinforced concrete (RC) floor slab, especially in areas above pile foundations, where the stiffness of subgrade is much higher. The research provides a solution to achieve the required level of settlement dissimilarity in areas where there are piles underneath a building slab under the columns. The paper proposes a new integrated method for the evaluation of the subgrade reaction coefficient above the pile cap. The proposed method optimizes design time and eliminates the need for specialized geotechnical software. Obtained results confirmed the efficiency of the proposed design method.

Queueing analysis of the replenishment of multiple in-the-aisle pick positions

A case-picking operation with Multiple In-The-Aisle Pick Positions (MIAPP) is modeled as an M/G/1/N queueing system. Cases are picked manually from pallets located on the bottom level of storage racks. An aisle-captive Narrow-Aisle Lift Truck (NALT) travels rectilinearly to replenish the floor level of the rack by retrieving a pallet load from an upper level of the rack. From a queueing perspective, the NALT is the server and the order-picking positions in need of replenishment are customers. In this article, the replenishment requests from order-picking positions are assumed to occur at a Poisson rate (i.e., homogeneous customers). The corresponding probability density functions of service times are derived, and their Laplace–Stieltjes transforms are obtained, leading to steady-state performance measures of the system. In many situations, the replenishment requests from individual pick positions may not follow a homogeneous Poisson process, and the order-picking operation consists of heterogeneous customers. However, a simulation study indicates that an M/G/1/N queueing model yields accurate performance measures in such situations. Interestingly, when the number of pick positions is large enough to justify an MIAPP-NALT operation, the time between consecutive replenishment requests within a storage/retrieval aisle is approximately exponentially distributed. A numerical example is provided to illustrate the use of the developed model and to show the practical values of the analytical results in the performance analysis of such storage/retrieval systems.

Rediseño de un triciclo de carga pesada, libre de contaminación

The tricycle is a widely used tool nowadays due to its versatility, since it allows effectively transporting all types of loads such as: construction materials, fruits and vegetables, traveling businesses, and even human passengers. Currently consists of three wheels two front and one back forming a triangle, its components are: tires, wheels, seat, lift truck, frame, transmission chain, multiplication, back gear, the counterpedal mass, among others. The article describes the redesign of a heavy load tricycle capable of loading 700 kg without deforming its structure. For this purpose, it follows the design process proposed by Budynas and Nisbett in his book "Design in Mechanical Engineering of Shigley". Likewise, the design and simulation has been worked in a trial version of the Siemens NX 10 software, which is a CAD software. The plans of all the designed components are presented, as well as a graph of their assembly.

Use of a computer simulation program to quantify the influence of masking calculation methods on ISO 5006-1 visibility results

IntroductionThe ISO 5006-1 is used to evaluate visibility on earth-moving machinery but has been criticized for a cumbersome field method. Field conditions are difficult to reproduce. Investigators may be required to evaluate a particular machine's line of sight profile to examine how it contributed to an accident. However, the standard relies on values such as operator size and positioning that accident investigators may not possess. Furthermore, practitioners in various settings face limitations related to lighting, time, and space. MethodsA computer simulation version of the standard was completed on a small lift truck machine and a larger haul truck. Variations on obstruction, or masking, calculation methods were completed to highlight the variability within the ISO 5006-1 standard under controlled conditions. Additionally, the impact of operator anthropometrics and seat positioning on masking measurements were quantified. ResultsGenerally, ISO 5006-1 calculated masking widths and those measured using a monocular view point underestimated masking sizes as compared to a gold standard binocular measurement. Binocular and monocular measurements of the percentage visibility on a horizontal plane showed little difference (<1%). Furthermore, variations in operator anthropometrics and seat positioning showed minimal changes in measures of visibility (<2%). ConclusionsDepending on the accuracy required for a given application, variations in visibility measurements may be considered acceptable or unacceptable. The variation of 300 mm observed in one case between a binocular masking width and monocular width exceeds the acceptable masking width (300 mm) defined by the ISO. However, variations in seat positioning and anthropometrics showed much smaller differences.

Comparison of epidemiology and injury profile among injured patients involved in incidents by special purpose vehicle

This study examined injuries related to mobile machinery or special purpose vehicle (SPV) mainly used in agriculture (tractor), industry (forklift or lift truck, mobile crane), and construction (gr...

Nomination of controls of various layouts for heavy machinery.

Control selection in heavy machinery may be a problem due to the poor compatibility of the commonly-used single line of vertical levers for controls. This study examined the effects of control arrangements on directional compatibility and participant responses in terms of choice/function of controls. We investigated experimentally, for a number of new designs of control arrangements, the selection of controls for requested functions of four different machines: fork lift trucks, excavators, tower cranes, and telescopic cranes. Control arrangements were designed with different levels of directional compatibility and participants were requested to nominate which control was related to each of the machine motions and to make ratings of certainty of response. A second part required participants to rank the various control arrangements in terms of their compatibility. The in-line control arrangement was worst for each machine and increased directional compatibility improved the stereotype strength, certainty of response and ranking of control arrangement. Directional compatibility is the main factor in the design of control/machine output arrangements due to its effect on stereotype strength and correct selection of control of a given function.

2.5 톤 저상형 고소작업차량 붐 조인트의 최적설계

Due to urbanization, parameters such as large size and height constrain the workspace of aerial lift truck. An aerial lift truck with reduced height was developed to decrease the telescopic boom. Based on FEM Analysis, the failure was localized to the shaft of the boom joint. Shape optimization was ...

Element 1 scalable hydrogen generator for materials handling

Oregon-based Element 1 has launched its L-Series hydrogen generator, targeted at hydrogen refueling for logistics mobile applications including fuel cell powered lift trucks, yard-spotters, tuggers, container handlers, and other heavy-duty equipment. The L100 hydrogen generator is the first product to be rolled out under the L-Series platform, in response to customer demand for dealer-focused hydrogen generation.

Ballard to develop next-gen, air-cooled stack for forklift trucks

Canadian-based Ballard Power Systems has signed a Technology Solutions programme with an unnamed strategic customer, to develop a next-generation, air-cooled, hydrogen PEM fuel cell stack for use in Class 3 lift trucks while enabling significant cost reductions.

Test verification of a seat-cabin system vertical dynamic model for high-grade fork lift trucks

The seat-cabin system of fork lift trucks has a great influence on ride comfort. On the basis of the structure and characteristics of the seat-cabin system for a high-grade fork lift truck, a seat-cabin system vertical dynamic model was created. The vertical dynamic responses of the model under the random irregularities excitation were calculated. The calculated responses including the seat dynamic response and the cabin dynamic responses at the four corners are very close to the field measurement data and the relative deviations of the (root mean square) RMS acceleration responses are all less than 6.0%. The results show that the vertical dynamic model is acceptable and can truly describe the basic mechanical behavior of the seat-cabin system. The model provides a good basis for investigating the relations between the dynamic parameters and the vibration attenuation characteristics of the seat-cabin system to further improve ride comfort.

Sensor Integration-Based Approach for Automatic Fork Lift Trucks

In the industrial environment, the flow of materials is a complex and very expensive process. For reducing the expenses, it requires an effort to find favorable and flexible systems. Fork lift trucks are widely used in industries for transfer actions. The complexity of manually operated fork lift trucks shall be reduced by low cost automation. This paper deals with sensor interfaced automatic fork lifter for the effective materials flow. This fork-lift truck will identify the different pallets automatically based upon their surface color by the color sensor interfaced with it. The digital output of the color sensor varies with respect to the wavelength of the color. This output decides the selection or rejection of the pallets for loading as well as unloading anywhere. Line following technique is used for transportation between sections to avoid the complexity of conventional memory mapping technique.

Optimized scheduling for electric lift trucks in a sugarcane agro-industry based on thermal, biomass and solar resources

Resource scheduling for both cost and pollution minimization in the power system is so crucial. To reduce the greenhouse gas emission, employing renewable energy resources, especially solar and wind energy, and beside them plug-in hybrid electric vehicles are effective solutions. In industrial factories, using biomass resources for power generation is both economic and environmental approach. In sugarcane company, bagasse is plant fiber residue which is used as fuel. Electric lift trucks, capable of being connected to power grid, could decrease the pollution in industrial transportations. In this paper, scheduling problem for a large-scale sugarcane factory including solar resources, a thermal unit, and electric lift trucks is presented and solved by CPLEX solver in GAMS software. In order to consider uncertainties, different scenarios are noticed. To contribute better understanding of optimization problem, cost, pollution, and charging regime of electric lift trucks are carefully analyzed. The results show that implementation of the biomass electric power generation is effective for reducing cost and amount of emission.