Reducing truck emission by reducing truck weight: The development of a new lightweight axle lift system driven by electric motor

Abstract

Volvo GTT has long been one of the most prominent players in the global commercial ve hicle market and a key player in developing new technology for a safer and greener future. With the ever-increasing focus on emissions and fuel efficiency in the retail vehicle market, the segment is shifting towards greener solutions to meet regulations. This holds true even for heavy-duty and long-haul trucks, which come with many challenging tasks. One way to make trucks greener is to reduce the truck’s weight. There are regulations on the maximum weight of a loaded truck. By lowering the truck’s weight, the user can increase the amount of cargo per transportation, thus improving the ratio of the truck to cargo weight - leading to more emission-efficient transportation of cargo. A truck contains several axles to split heavy loads it has to carry. When the truck is unloaded, extra axles are inconvenient. They lead to increased energy consumption by higher road friction and increased tire wear. Currently, the axles are lifted in these cases through air bellows axle lift systems. Due to the requirement of large and heavy levers to transfer the lifting force from the air bellows to the axles, the current solution is heavy and requires a lot of packaging space. This product development project aimed to conceptualize and create a new solution for the current system to find a lightweight concept. The product aims to keep the same robustness and efficiency as the air bellow axle lift system while weighing less. During the project, a new lifting system was developed. The solution works based on connecting a sliding screwing device to the dampers of the axles. An electric motor then actuates the sliding screw. The product uses a sliding mechanism to handle unpredicted external forces during the lifting process, such as road bumps. A detailed design CAD model was created and a prototype of the concept. Tests were done using both physical measurements of the prototype, analyses of the CAD model, and calculations based on data from available databases. During tests performed for validation purposes, it was seen that the concept manages to properly handle the lift of the axle. It does so while weighting 75% less, costing 34% less and reducing main assembly line steps in the factory by 66%. Also, conducted environmental EPS studies showed an 80% reduction in material emission cost.