A New Method of Climbing on a High Place by Elasticity-Embedded Rocker-Bogie Vehicle with Dynamic Motions

The rocker-bogie mechanism increases the capacity of vehicles to step over steps. When it comes to climbing steps, however, the rocker-bogie vehicle depends on the length of the links and friction force between the wheels and the vertical plate of steps. Therefore, we propose a new method that enables the elasticity-embedded rocker-bogie vehicle to climb a high place with low dependency on the friction force and length of links. Firstly, it lifts up the links of the elasticity-embedded rocker-bogie vehicle with the excitation of Series Elastic Actuator (SEA). Secondly, it keeps the posture of lifted links with inverted pendulum control. Thirdly, the rocker-bogie vehicle moves forward to the step and puts some wheels there with the link-lifted posture keeping. Finally, put all wheels on step by another dynamic motion. We verified and succeeded up to the third phase of the proposed method in both the simulation and the actual robot.