Research on steering-tilting characteristics of an active tilting three-wheeled vehicle

Active tilting narrow vehicles can prevent rollover and improve riding stability through active tilting technology during steering, but it is difficult to obtain the turning radius and solve the optimal tilting angle. In this paper, based on the active tilting three-wheeled vehicle (ATTWV), the geometric analysis method of steering wheel’s alignment was proposed and used to calculate the specific formula of turning radius during steering and tilting, and the effect of tilting on the turning radius was studied. Based on the steering and tilting mathematical model of force equilibrium state, the ideal tilting angle was solved and the S-shaped curve steering test verification was carried out with the prototype vehicle. The results show that the lateral acceleration of the vehicle fluctuates within ±0.16 g during steering, realizing the equilibrium between the component of gravity and centrifugal force. The average error between the actual tilting angle and the calculated ideal tilting angle is 1.18°. Based on steering and tilting mathematical model of the rollover critical state of the ATTWV, the safe turning speed under the specific tilting angle can be solved, and the value range of the tilting strength coefficient can be obtained, which provides not only a reference for the control of ATTWVs but also a theoretical basis for the research on accurate self-driving control of the active tilting narrow vehicles in the future.