<p>Mechanical vibration sputum clearance is commonly used for airway clearance. However, existing handheld vibration-assisted expectorators confront several challenges including operator's hand fatigue and a high risk of cross-infection between medical staff and patients. To address these issues, this study presents a novel design for an intelligent percussion-based sputum clearance robot. The robot is designed to assist medical staff in providing percussion-based sputum clearance nursing for patients. Initially, the structure of the robot is designed based on the environmental conditions in the intensive care unit (ICU). To mitigate the impact of the vibrations generated by the vibration percussion head on the robotic arm operation, a fixture equipped with a vibration damper is designed to ensure that the robot's standard functionality remains unaffected. Furthermore, a human back detection (HBD) framework constructed from multi-subtask modules is proposed to address the shortcomings of existing robotic systems in terms of human perception capabilities. These modules are designed to accurately identify and map the anatomical features of the human back. This effectively improves the capability of the robot to interact with the human body. Based on this framework, the robotic arm is controlled precisely to emulate the percussion strategies employed by physicians. Finally, extensive experiments are conducted in a real-world setting with multiple participants. The results indicate that the robot could provide percussion-based sputum clearance nursing that is practically equivalent to the operations by medical staff.</p>