Abstract: In order to get a tractor frame structure which meets the requirement of static multi-stiffness and dynamic natural frequencies in conditions,the topology optimization was introduced into the design of frame structure.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.The simulation result shows that the frame can meet the performance requirement,which verifies that the rationality of multi-objective topology frame design is feasible.

Key words: tractor frame, multi-objective, topology optimization, compromise programming