Orientation Control System: Enhancing Aerial Maneuvers for Quadruped Robots

TL;DR

This paper introduces an Orientation Control System using reaction wheels to improve aerial maneuverability of quadruped robots during flight phases, enabling better orientation control when airborne.

Contribution

The paper presents a novel compact orientation control system with two reaction wheels that can control roll and pitch angles during flight, enhancing aerial capabilities of legged robots.

Findings

Successful simulation results on Solo12 robot

Effective control of robot orientation during flight

Compact design of the orientation control system

Abstract

For legged robots, aerial motions are the only option to overpass obstacles that cannot be circumvent with standard locomotion gaits. In these cases, the robot must perform a leap to either jump onto the obstacle or fly over it. However, these movements represent a challenge because during the flight phase the Center of Mass (CoM) cannot be controlled, and the robot orientation has limited controllability. This paper focuses on the latter issue and proposes an Orientation Control System (OCS) consisting of two rotating and actuated masses (flywheels or reaction wheels) to gain control authority on the robot orientation. Because of the conservation of angular momentum, their rotational velocity can be adjusted to steer the robot orientation even when there are no contacts with the ground. The axes of rotation of the flywheels are designed to be incident, leading to a compact orientation control system that is capable of controlling both roll and pitch angles, considering the different moment of inertia in the two directions. We tested the concept with simulations on the robot Solo12.