Multi-objective Topology Optimization Design And Analysis Of Tractor Frame

With the development of expressway network, the trailer has become an important vehicle in the logistics market based on its security and transport efficiency. As a power source of semitrailer, the development of tractor is highly valued by commercial vehicle enterprises. As a main bearing component of tractor, the performance of frame directly affects the performance of tractor.Therefore, whether design a frame which has a good mechanical properties,light weight and low manufacturing cost becomes particularly important. In order to avoid the blindness in the traditional design, the topology optimization methods has been introduced into the structural design of tractor frame in this paper, which not only provides a scientific design to designers, but also find the most reasonable design.In the past, the single objective topology optimization which just considers compliance as a minimum objective function is used in the topology optimization design of frame.In practice, the working conditions of frame is complex, single objective topology optimization design can not obtain the best frame structure. In order to get a tractor frame structure which meets the requirement of static multi-stiffness and dynamic natural frequencies inconditions, the multi-objective topology optimization was introduced into the design of frame structure in this paper. A compromise programming method was adopted to establish the mathematical model of multi-stiffness topology optimization, while the average frequency method was adopted to settle the mathematical model of the objectives of natural vibration frequencies topology optimization, and compromise programming method was also adopted to establish the mathematical model of multi-objectives which combined stiffness and natural vibration frequencies. A reasonable topology structure of frame which met the requirement of multi-stiffness and natural frequencies was obtained at the same time.According to the results of topology optimization, the three-dimensional model of the topology optimization frame was built by Pro/E, which was imported to Hypermesh where finite element static and modal analysis was completed. The results show that the topology optimization frame meets the requirement, the static and modal properties are generally superior to the original frame and overall weight losses 5.01%. The simulation result also verifies the rationality that multi-objective topology optimization design is introduced to the frame design.In the market environment of pursuing safety, environmental protection,weight loss and consumption-reducing, the lightweight design of the tractor frame is very necessary. In the premise of meeting the performance of the tractor,size optimization design was performed to the topology optimization frame, thenthe finite element static and modal analysis was completed for the size optimization frame. The results show that the size optimization frame meets the requirement, the static and modal properties generally further improve than the topology optimization frame and overall weight losses 13.56%, a obvious weight loss. In the pursuit of saving material and improving vehicle fuel economy today, the final size optimization frame has a stronger market competitiveness.