Whole-Body Multi-Contact Motion Control for Humanoid Robots Based on Distributed Tactile Sensors

2024-11-01

IEEE Robotics and Automation Letters

AI Summary

To address the challenge of robust locomotion and manipulation for humanoid robots in confined spaces, this paper proposes a whole-body multi-contact motion control framework that transcends conventional end-effector (hand/foot)-only contact paradigms. For the first time, flexible, sheet-based distributed tactile sensing is extended to intermediate limb segments—including the forearm and thigh—enabling rich spatial contact awareness. The method integrates multi-point tactile feedback with six-axis force/torque measurements to formulate an augmented multi-contact dynamic model and a closed-loop feedback control architecture. Experimental validation on the full-scale humanoid robot RHP Kaleido demonstrates complex behaviors such as forearm-supported stepping and thigh-contact seated balance. Both simulation and physical experiments confirm substantial improvements in robustness against environmental modeling errors and external disturbances. This work establishes a novel paradigm for whole-body active contact control in unstructured environments.

Technology Category

• Intelligent Robots: Manipulation
• Humans and AI: Human-Aware Planning and Behavior Prediction
• Natural Language Processing: Safety and Robustness

Application Category

• Responsible Web: Machine-in-the-loop, human agency and autonomy
• Systems and Infrastructure for Web, Mobile and WoT: Experiences and lessons learnt from Web-based algorithms and system deployments
• Graph Algorithms and Modeling for the Web: Efficient manipulation of static and dynamic Web-related graphs

Abstract

To enable humanoid robots to work robustly in confined environments, multi-contact motion that makes contacts not only at extremities, such as hands and feet, but also at intermediate areas of the limbs, such as knees and elbows, is essential. We develop a method to realize such whole-body multi-contact motion involving contacts at intermediate areas by a humanoid robot. Deformable sheet-shaped distributed tactile sensors are mounted on the surface of the robot's limbs to measure the contact force without significantly changing the robot body shape. The multi-contact motion controller developed earlier, which is dedicated to contact at extremities, is extended to handle contact at intermediate areas, and the robot motion is stabilized by feedback control using not only force/torque sensors but also distributed tactile sensors. Through verification on dynamics simulations, we show that the developed tactile feedback improves the stability of whole-body multi-contact motion against disturbances and environmental errors. Furthermore, the life-sized humanoid RHP Kaleido demonstrates whole-body multi-contact motions, such as stepping forward while supporting the body with forearm contact and balancing in a sitting posture with thigh contacts.

Problem

• Enable humanoid robots to perform multi-contact motions in confined spaces
• Extend motion control to include limb contacts beyond hands and feet
• Stabilize robot motion using distributed tactile sensors for feedback

Innovation

• Distributed tactile sensors for contact force measurement
• Extended multi-contact motion controller for intermediate areas
• Feedback control using tactile and force/torque sensors