Virtual Testing of Counterbalance Forklift Trucks: Implementation and Experimental Validation of a Numerical Multibody Model

Abstract

This study investigates the dynamic behavior of a recently developed counterbalance forklift truck. The final objective is creating virtual testing tools based on numerical multibody models to evaluate the dynamic stresses experienced by the forklift family of interest during a reference operating cycle, defined by the manufacturer’s testing protocols. This work aims at defining sufficiently accurate and easy-to-implement modelling approaches and validation procedures. It focuses on a specific test, namely the passage of a speed-bump-like obstacle at high velocity, which represents one of the most severe conditions within the reference cycle. Indeed, unlike most of the other wheeled vehicles, forklifts typically do not have advanced suspension systems and their dynamic response is significantly affected by ground irregularities. To this end, a preliminary model of the complete forklift, featuring rigid bodies and a simplified tire–ground contact model, is implemented with a commercial software. Experimental tests are conducted on the forklift to measure the vehicle vibrations when running on the obstacle, for model validation purposes. After model updating, the results provided by the numerical simulations match the experimental data satisfactorily. Hence, the modelling and validation strategies are proven viable and effective.

Striated Tire Yaw Marks—Modeling and Validation

“…In case of uncommon suspension systems and/or different tire types, e.g., forklift trucks [25,26] or other uncommon vehicles [27], the response of the unsprung masses is Remarks. The yaw mark creation model will still be valid on arbitrary 3D roads and typical road irregularities.…”

“…In case of uncommon suspension systems and/or different tire types, e.g., forklift trucks [25,26] or other uncommon vehicles [27], the response of the unsprung masses is not expected to affect the striated yaw mark creation model effectiveness as long as the vehicle is moving along a non-deformable surface and the road wavelength is not larger than the tire circumference.…”

Application of Wireless Accelerometer Mounted on Wheel Rim for Parked Car Monitoring

“…Because the sensing heads are often installed in the sprung part of the vehicle, obtained results of acceleration are influenced by the spring and damping forces. The interesting case of accelerometer use for monitoring the driving characteristics is accelerometers mounted on the wheel hubs [37].…”

Optimal Vibration Suppression Modification Method for High-Speed Helical Gear Transmission of Battery Electric Vehicles under Full Working Conditions

“…Hu [15] et al studied the effect of modification coefficient and helix angle on the transient meshing performance of gears with respect to energy using explicit dynamic finite element analysis, obtaining the relationship between transient meshing performance and gear modification coefficient and helix angle. Martini [16] et al investigated the dynamic behavior of counterbalance forklift trucks in order to create a virtual test tool based on a numerical multi-body model to evaluate the dynamic stresses experienced by the main structural components of a specific series of counterbalanced forklift trucks. Schliermann [17] et al developed bevel gearboxes for electric industrial trucks in which the drive motor is arranged vertically, which ensures a very compact design.…”