A novel modifiable walking pattern generator on an inclined plane in pitch and roll directions for humanoid robots

In previous researches on walking on an inclined plane of humanoid robots including the 3D linear inverted pendulum model (3D-LIPM) approach, the humanoid robots were not able to independently modify walking period and sagittal and lateral step lengths without any additional step for adjusting the center of mass (CM) motion. Moreover, the walking on the inclined plane in pitch direction was only considered. In order to overcome these problems, a novel modifiable walking pattern generator for humanoid robots is proposed for modifiable walking on an inclined plane in both pitch and roll directions. The dynamic equation of the 3DLIPM on the inclined plane in both pitch and roll directions is derived to obtain the CM motion. Using the CM motion, a method for modifiable walking pattern generation on the inclined plane is developed to follow a navigational command set composed of walking period and sagittal and lateral step lengths. The proposed algorithm is verified through computer simulations carried out with a simulation model of the small-sized humanoid robot, HanSaRam-IX (HSR-IX).