Task-Adaptive Admittance Control for Human-Quadrotor Cooperative Load Transportation with Dynamic Cable-Length Regulation

2026-04-20

AI Summary

This study addresses the lack of safe and responsive physical interaction control methods in human–quadrotor collaborative payload transport by proposing a task-adaptive admittance controller that, for the first time, integrates an active tether-length regulation mechanism. By dynamically adjusting both admittance parameters and tether length, the approach effectively decouples the complex dynamics of the human–robot–payload system, thereby enhancing interaction safety and responsiveness. Experimental results demonstrate that, under varying stiffness and tether-length conditions, the proposed method significantly outperforms conventional approaches, achieving substantially improved system response speed and motion smoothness, and thus advancing overall performance in human–robot cooperative transportation tasks.

Technology Category

• Intelligent Robots: Human-Robot Interaction
• Humans and AI: Interaction Techniques and Devices
• Cognitive Modeling & Cognitive Systems: Adaptive Behavior

Application Category

• Responsible Web: Machine-in-the-loop, human agency and autonomy
• Economics, Online Markets and Human Computation: LLM based quality controls for crowd work
• User Modeling, Personalization and Recommendation: User modeling and simulation for interactive and conversational systems

Abstract

The collaboration between humans and robots is critical in many robotic applications, especially in those requiring physical human-robot interaction (pHRI). Previous research in pHRI has largely focused on robotic manipulators, employing impedance or admittance control to maintain operational safety. Conversely, research in human-quadrotor cooperative load transportation (CLT) is still in its infancy. This letter introduces a novel admittance controller designed for safe and effective human-quadrotor CLT using a quadrotor equipped with an actively-controlled winch. The proposed method accounts for the system's coupled dynamics, allowing the quadrotor and its cable to dynamically adapt to contact forces during CLT tasks, thereby enhancing responsiveness. We experimentally validated the task-adaptive capability of the controller across the entire CLT process, including in-place loading/unloading and load transporting tasks. To this end, we compared the system performances against a conventional approach, using both variable and fixed cable lengths under low- and high-stiffness conditions. Results demonstrate that the proposed method outperforms the conventional approach in terms of system responsiveness and motion smoothness, leading to improved CLT capabilities.

Problem

• human-quadrotor cooperation
• cooperative load transportation
• physical human-robot interaction
• dynamic cable-length regulation
• admittance control

Innovation

• task-adaptive admittance control
• human-quadrotor cooperation
• dynamic cable-length regulation
• cooperative load transportation
• physical human-robot interaction