Dynamic Performance Simulation Analysis of Electric Forklift Truck Based on ADVISOR

According to the power system selection and technical parameters of the lithium titanate electric forklift that have been matched, the ADVISOR simulation software modeled the parameters of the drive motor, lithium titanate battery, reducer and other major components of the system. The acceleration ability, climbing ability and energy consumption of lithium titanate-electric forklift are simulated, and its technical parameters are obtained, which provides a basis for testing the rationality of system parameter matching.

Variable universe fuzzy control of the lateral stability of forklift trucks based on roll grading

Based on the structural analysis and the roll mechanisms of counterbalanced forklift truck, a novel type of 3-link hydraulic supporting mechanism is designed as an actuator for forklift anti-rollover control. A rollover grading control strategy of the lateral stability of counterbalanced forklift truck is proposed, which is used to design a variable universe fuzzy controller. The variable universe fuzzy control of the first-order roll is utilized when the forklift is in the first-order roll, whereas the variable universe fuzzy control of the second-order is used when the forklift is in the second-order roll. A virtual prototype model of forklift is built in Automatic Dynamic Analysis of Mechanical Systems (ADAMS). The co-simulations and vehicle tests are implemented, the results indicate that the lateral stability and active security of the forklift could be improved effectively by using the variable universe fuzzy control strategy of the lateral stability of forklift truck based on roll grading.

Injuries after Forklift Trucks Accidents – Injury Patterns, Therapy and Outcome in the Context of the Statutory Accident Insurance

Introduction The use of forklift trucks during work has a high accident potential. The aim of this study is to describe injury patterns, treatment and outcome after forklift truck accidents in the context of the employersʼ liability insurance association. Methods Retrospective data collection of all cases between 2004 and 2019. Excluded were patients < 18 years, without follow-up or with definitive external treatment. Trauma mechanism, injury patterns and distribution, treatment, complications, time of incapacity for work, return to work and impairment of earning capacity were recorded. Results Of 109 patients with 110 injuries, 52.7% showed isolated injuries and 47.3% combined injuries, which affected the lower extremity in 95 cases. There were fractures in 85.5%, including 32.7% in open form. The mean length of stay was 29.1 days (range 1 – 129); an indication for surgery was seen in 80.9%. Surgical treatment required an average of 3 interventions, with significantly more operations for soft tissue closure than for the fractures (p ≤ 0.023). Amputations were necessary in 8 cases; complications occurred in 29.1%. Return to work was possible in 90%, after a mean period of incapacity for work of 33.6 weeks. A total of 40% showed a pensionable impairment of earning capacity. Conclusion Accidents with forklift trucks result in complex lower extremities injuries with the need of multi-stage treatment and show relatively high complication rates. A return to work is often possible after a long period of convalescence, and a pensionable impairment of earning capacity often persists.

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

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.