Structural Design And Finite Element Analysis Of The Two-wheeled Self-balancing Electric Vehicle

Both the two-wheeled self-balancing electric vehicle and the two-wheeled self-balancing robot belong to the two-wheeled self-balancing system. Compared with the latter, the two-wheeled self-balancing electric vehicle requires more on performance and security. In recent years, studies of the two-wheeled self-balancing robot are too numerous to mention, and most of them focus on the control but not the structure. As a striking contrast, studies of the two-wheeled self-balancing electric vehicle can rarely be seen. After having summarized the research results of the field, this thesis designed and analyzed the mechanical structure of the two-wheeled self-balancing vehicle successfully. All the work can be listed as below:1) After having analyzed the mechanics of two-wheeled self-balancing system, a necessary condition was gained, which provided the basis for the following designs.2) A two-wheeled self-balancing electric vehicle was designed, overcoming all the weak points of the relative patents which could be found domestically. The design integrated a medium-speed motor and a reductor in the wheel, which was beneficial to improve the mechanical properties and the efficiency of the motor. The sunken suspension could both improve driving comfort and simplify the control of the dynamic-balance. Aluminum alloy sections were widely used in the design in order to reduce the mass of the vehicle under the premise of enough mechanical properties. The results of the design could meet the pre-requirements properly.3) After having analyzed the mechanical properties of the critical components of the vehicle in ANSYS, they were found to have met the requirements. This showed that the design was reasonable to a certain degree. Some of the components had a considerable rigidity or strength margin. After optimizations their mass was reduced largely but the mechanical properties were still satisfactory.4) In order to solve the problem of a small-sized transporter's power lack when it starts or climbs a slope, the thesis took the opportunity of researching the two-wheeled self-balancing vehicle, raising a new structure concept which could shift automatically. When the velocity is below the critical value, the vehicle navigates on the lower gear, in order to get a good power performance, and when the velocity exceeds the critical value, the reductor can switch to the higher gear automatically, so as to meet the speed requirement and make good use of the speed range of the motor. Based on this concept, a coarse model of the vehicle was made. In order to provide basis for the design of a critical component in the structure, a testing device was also designed, and all the drawings were given.