Numerical investigation on the quasi-static compression characteristics of bio-inspired horizontally grooved square tubular structure for the application in crash boxes

Crashworthiness is vital for vehicle safety. It ensures structures absorb impact efficiently, reduces occupant injuries, and enhances survival rates. This increases the demand for researchers to design and optimise the crash box with better crashworthiness parameters. The research aims to evaluate the effects of horizontal grooves inspired by bamboo nodes on the crashworthiness of square tubular structures in crash boxes, optimising their design for improved safety. AL6063 square tubes (50 × 50 mm cross-section, 3 mm thickness, 140 mm height) with 0, 2, 4, 6, and 8 horizontal square grooves (1 mm size) were modelled with a CAD programme. Finite Element Analysis (FEA) was performed using the FEA programme to assess crashworthiness parameters, including Energy Absorption (EA), Specific Energy Absorption (SEA), Initial Peak Crushing Force (IPCF), Mean Crushing Force (MCF), and Crush Force Efficiency (CFE). The four-grooved tube reduced IPCF by 16.81%, increased EA by 4.85%, SEA by 5.9%, MCF by 6.4%, and CFE by 27.91% compared to the plain tube. Incorporating four horizontal grooves optimises crashworthiness, with performance declining beyond this number. Thus, four grooves provide the best enhancement for crash boxes.