Realization of Seated Walk by a Musculoskeletal Humanoid with Buttock-Contact Sensors From Human Constrained Teaching

TL;DR

The paper tackles seated walk on a musculoskeletal humanoid by introducing buttock-contact sensors embedded in the planar interskeletal structure and a constrained teaching method that learns only transition thresholds for one-dimensional control commands. A buttock-Contact Balancer using a PI controller maintains balance during asymmetric contact, enabling stable translation and rotation on a chair. The authors demonstrate forward, backward, and rotational seated walking and a bag-carrying scenario, achieving complex motions from simple taught inputs. The work advances human-like robotics by enabling environment-contact locomotion with flexible, teachable control in a quasi-static regime, and points to future integration with manipulation and navigation for fuller mobility in real-world settings.

Abstract

In this study, seated walk, a movement of walking while sitting on a chair with casters, is realized on a musculoskeletal humanoid from human teaching. The body is balanced by using buttock-contact sensors implemented on the planar interskeletal structure of the human mimetic musculoskeletal robot. Also, we develop a constrained teaching method in which one-dimensional control command, its transition, and a transition condition are described for each state in advance, and a threshold value for each transition condition such as joint angles and foot contact sensor values is determined based on human teaching. Complex behaviors can be easily generated from simple inputs. In the musculoskeletal humanoid MusashiOLegs, forward, backward, and rotational movements of seated walk are realized.

Figures (11)

• Figure 1: Seated walk by the musculoskeletal humanoid MusashiOLegs.
• Figure 2: The musculoskeletal humanoid MusashiOLegs onitsuka2021musashiolegs with various planar interskeletal structures.
• Figure 3: The implementation of buttock-contact sensors in the planar interskeletal structure of gluteus maximus.
• Figure 4: The difference in buttock-contact forces with various ways of sitting.
• Figure 5: The procedures of constrained teaching method: preparation, teaching, and reproduction.