Sustainable Design and Technical Conflict Resolution of a Modular UAV Cleaning System for High-Rise Glass Facades

High-rise glass curtain wall cleaning has long relied on dangerous manual high-altitude operations, which suffer from low efficiency, high labour costs and prominent safety hazards. Existing cleaning robots generally lack a systematic user demand-driven design framework, making it difficult to balance safety, obstacle-crossing capability and maintenance performance. To fill this gap, this study proposes a four-stage integrated sustainable design methodology integrating the KANO model, Analytic Hierarchy Process (AHP), Quality Function Deployment (QFD) and TRIZ. This methodology covers requirement attribute classification, priority weight quantification, demand-technology mapping and engineering conflict resolution, which can assist in sorting out multi-constraint design contradictions for the studied high-altitude cleaning equipment. Applying this methodology, the study develops the modular NetWing curtain wall cleaning drone with a vertically separable structure, retractable obstacle-crossing cleaning arm and quick-release cleaning head, and the feasibility of the conceptual scheme is preliminarily verified through numerical simulation. This work provides a quantifiable and replicable design paradigm for high-altitude service equipment, and the proposed solution can effectively reduce occupational risks and support the sustainable development of the facade cleaning industry.