Façade Cleaning Robot for Convex-Shaped Infrastructure: Design and Experiment

Abstract

This study developed an integrated robot platform, Edelstro-S, for managing complex-shaped building exteriors, addressing two key limitations of existing ascender robots: insufficient wall adaptation capability and workspace constraints. The hybrid system integrates ascender, wheel-leg, and anchor subsystems, in which the ascender defines a rope-length-constrained workspace and the wheel-leg subsystem provides high-speed surface movement and obstacle traversal within it. Mathematical modeling was used to analyze the workspace and singularity characteristics of the cable-driven parallel ascender mechanism, as well as the kinematics and static stability of the wheel-leg subsystem. Component-level and system-integration tests were conducted on the fabricated 79.75 kg platform in both laboratory and outdoor environments. The results show an ascending speed of 21.84 m/min and a descending speed of 22.93 m/min, a multisensor-fusion position estimation accuracy of 7.30 cm, successful traversal of obstacles up to 500 mm in height, stable operation under wind speeds up to 9.4 m/s, a minimum turning curvature radius of 0.4 m, and a maximum cleaning speed of 4.8 m2/min. These results demonstrate the platform’s adaptability to the irregular geometries of modern building façades and its potential to automate high-risk exterior maintenance tasks while improving worker safety.