342 Research Article International Journal of Current Engineering and Technology ISSN 2277 - 4106 © 2013 INPRESSCO. All Rights Reserved. Available at http://inpressco.com/category/ijcet Dynamic Analysis of Forklift during Load Lifting using Modeling and Simulations Ilir Doçi a * and Vegim Imeri b a,b University of Prishtina, Faculty of Mechanical Engineering, St. Sunny Hill, n.n., 10000 Pristina, Kosova Accepted 24 March 2013, Available online 1June 2013, Vol.3, No.2 (June 2013) Abstract Studying dynamic occurences on forklift during lifting of loads proves to be difficult using physical experimentation and current measurement devices. Creating the forklift’s multibody model and applying computer simulations is very usefull method to study these occurences, which helps to explain the reasons of heavy oscillations, failures and accidents of forklifts, and gives conclusions that can be useful for design considerations and safety. The aim is to see how dynamic forces, moments, speed and oscillations effects the forklift’s construction and its stability during load lifting. To do thi s work we designed entire “virtual forklift” using model design and simulation applications (Fig.2) [3] and performed simulations in order to gain results. Main parameters that are influential on the dynamic behavior of forklift will be analyzed and will be searched for conclusions that can be useful for better understanding dynamics of forklift. This paper identifies a set of parameters that have influence in main forklift parts, and gives results with graphs and tables with values that are dynamic in nature, with high amplitudes and frequencies that effects directly in causes of material fatigue or failure. Keywords: Forklift, modeling, simulation, load lifting, dynamic analysis, oscillations, FEM 1. Introduction 1 Work of warehouse forklifts is characterized by various working processes – lifting weight, lowering weight, moving forward, moving backwards, moving left and right, with numerous requests and cycles which includes variety of cargo and packages that needs to be carried with variable speeds. The work of forklift while lifting weight (load) is considered most difficult process, particularly when it lifts the maximal load. Study will be done for the forklift of type Linde H20(Linde Material Handling GmbH) shown in fig. 1, which was available for testing in the warehouse of local company. Simulation will be achieved using Numerical methods (Kutta-Merson) and Finite Elements Method (FEM), supported by modelling and simulation software(Dresig et al,2001). Results of research will be shown for some main parts of forklift that lifst the load, with graphs and tables with resulting values and their comparisions, which offers new conclusions and good view in dynamic occurences. 2. Modeling of forklift and simulation of lifting process After the model creation with its parts in Inventor software, its modelled parts are imported in Visual Nastran 4D software and connected with proper constraints(Dresig * Corresponding Author: Ilir Doçi et al,2001). These constraints are rigid joints, revolute joints, rigid joints on slot, rope or revolute motor. The load that is lifted is created has prismatic form with dimensions (1200x800x1000 mm – palleted load), with mass of Q = 2000 kg which is maximal carrying weight of the forklift. We consider that best results of dynamic processes if the study is done with max carrying laod as given by manufacturer (Table 1). Fig.1. Photo of the forklift (Linde Material Handling GmbH) Simulations will be processed to achieve results of parameters which we consider are important for overall dynamic analysis(Dresig et al,2001). For the proper lifting process, lifting forks with load are placed in their lowest position (h=0.05 m), (Fig.3). Simulation will start without