Crashworthiness enhancement of three-wheel vehicle structures under rear-end collision: a computational modelling approach

Abstract

Worldwide, Three-wheeled vehicles (TWV) are becoming more and more ubiquitous for use in daily transportation. These vehicles are similar to motorcycles and scooters in that they have a steering wheel on the front, and they have a suspension system and differential on the back two wheels, just like a car. They typically consist of one front wheel and two rear wheels, with an open frame or sheet metal body. Their frontal design consists of an upright body and windscreen, a small cabin, a canvas roof, and a mudguard with an attached headlamp. These cars have a top speed of about 55 km/h. The front cabin houses the driver, while the back section is occupied by the passengers. It weighs about 650 kg, including the occupants. TWV are viewed as unsafe for two reasons: Auto rickshaws are thought to be dangerous for two reasons: first, the vehicle body and internal structure have no proper safety features, and second, the drivers are thought to be incompetent motorists who are ready to overload their cars and make numerous trips in a short amount of time. The driver’s seat and the back passenger bench are the only soft surfaces in the sparse, hard metal interior of auto-rickshaws, which are thought to be unstable and prone to turning turtle due to shunts from other vehicles, bumps in the road, or drivers who drive too fast. Because there are no doors, even at slow speeds, the occupants could be thrown onto the road and suffer serious injuries. Because of its materials’ and structures’ inadequate impact energy absorption, it also seriously jeopardizes pedestrian safety. The goal of this article was to reduce crash injuries by modifying the current three-wheeled vehicle to increase its crashworthiness during rear-end collisions. Accidents that happen to the rear ends of vehicles are the third most frequent type. Rear-impact collisions are frequent but rarely fatal. They do, however, cause a variety of injuries, the most frequent being whiplash trauma to the neck. In this study, the Federal Motor Vehicle Safety Standard (FMVSS)-301-inspired approach was followed when performing the Finite element analysis (FEA) rear-impact test on the TWV. Enhancing the crashworthiness of the car and the gasoline tank is another goal of the rear-impact test. Consequently, to see how occupants respond to a crash, human dummies are incorporated. Thus, modeling and analysis of the current three-wheeled vehicle structure with human dummies was the first task completed in this research. Following that, the outcome will be interpreted, and based on those findings, a new model will be developed to address the drawbacks of the three now in use. The outcomes of the original and modified models were then contrasted. Livermore Software Dynamic Nonlinear Analysis (LS-DYNA) was utilized for Finite element method (FEM) analysis, and CATIA was used for 3D modeling to accomplish this. From the result, the modified model is fitted with a rear bumper, so it reduces intrusion into the rear compartment of the vehicle. It deformed less, and as a result, 30% more protection was obtained for rear parts such as the fuel tank and engine. The rear bumper is made up of composite material, and this led to a greater absorption of energy with less deformation. The energy absorption of TWV was increased by 1.6 kJ. As a result, less energy is transferred to the occupants with the use of the modified model. With the use of the modified model, the force of impact was reduced by 22%; consequently, the occupants inside the modified model experienced fewer injuries. It can be observed that with little modification, the safety of the current TWV can be improved so that the owners and manufacturers can implement some of the safety development concepts discussed in this paper to improve the crashworthiness of the TWV.