Eventos Anais de eventos
COBEM 2021
26th International Congress of Mechanical Engineering
NONLILEAR FINITE ELEMENT SIMULATION AND STRUCTURAL VALIDATION OF SCHOCK ABSORBER USED ON TREADMILLS
Submission Author:
Mateus Piccin Duarte de Souza , SP
Co-Authors:
Mateus Piccin Duarte de Souza, Bruno Agostinho Hernandez, Marco Antonio Louzada Junior, Luiz paulo saito, EDSON CAPELLO SOUSA
Presenter: Mateus Piccin Duarte de Souza
doi://10.26678/ABCM.COBEM2021.COB2021-1135
Abstract
Abstract. In recent years, the number of people practicing physical activities has grown, with walking and running being one of the most popular options. Due to the lack of adequate places to practice physical exercises, mainly in big centers, there is an increasing search for gyms, where treadmills are widely used. However, the continued practice of these types of exercises can cause injuries, especially in the knees. To prevent them, treadmills often have efficient shock absorption systems, usually made up of cushions, which reduce the impact forces between the running surface and the person who is walking or running. Shock absorbers can generate varying impact absorption rates, depending on the materials and geometry adopted. If this component is not well developed, maintaining stability during the run, the person performing the exercise may be injured. Therefore, the objective of this study was to analyze, through finite element models and experimental analyzes, the mechanical behavior, in terms of impact absorption, of two different models of cushions used commercially on treadmills. The shock absorbers geometries were obtained from each manufacturer and modeled on the SpaceClaim module (ANSYS Inc., USA). The materials Natural Rubber 60 Shore A and TPU (Thermoplastic Polyurethane) were used, both were considered hyperelastic. To analyze the mechanical behavior, a non-linear static compression analysis of each shock absorber was performed (Workbench, ANSYS Inc., USA). The acting force ranged from 0 to 1000 N. To validate the results, the same simulated compression test was performed in the laboratory. 5 samples of each shock absorber were used and the same load was applied. From the results obtained, we could validate the finite element numerical model with the experimental model and verify that both models have a linear relationship between applied force and displacement and that the rubber damper elastic constant is 19% higher than the constant TPU shock absorber. The latter, with less complex geometry, 80% less mass and displacement of 16.2 mm when applying the maximum load, is more efficient in relation to the natural rubber damper, which presented a maximum displacement of 13.4 mm in the same condition. In future work, a study will be developed to increase the treadmill’s shock absorption system efficiency, optimizing the geometry and material, making it adaptable to the wide range of users and their weight variations.
Keywords
Impact, Shock Absorber, Treadmill, Finite Elements Analysis
