Walking Control of Quasi Passive Dynamic Walking Robot "Quartet III" based on Continuous Delayed Feedback Control

Passive-dynamic-walking (PDW) has been noticed in the research of biped walking robots. In this paper, combining our previous control methods, we provide a new control method of quasi-PDW. Quasi-PDW means that a robot usually does PDW without any input torques, and the actuators of the robot are used just only when the walking begins or disturbances come in. The first feature of the control method is that (k-1)th trajectory of the walking robot is used as a reference trajectory of the k-th step. The second feature is that a kind of gain scheduled PD control is adopted and its gains are regulated depending on the state of the contact phase of swing leg. As a result, it can be expected that the robot continues walking and the gait of the robot shifts from an active walking to PDW. The effectiveness of the control method is shown through several simulations and experiments with real walking robot "Quartet-III"