🤖 AI Summary
Existing lumped-jamming (LJ) continuum robot dynamic models rely on static or quasi-static assumptions, limiting real-time control that jointly regulates stiffness and deformation and failing to capture full dynamic behavior.
Method: This paper establishes the first control-oriented, energy-based dynamic model for LJ robots, uniquely integrating the LuGre friction model into the LJ mechanistic framework to theoretically characterize the coupled friction–jamming–deformation mechanism. The model is derived via energy-based formulation, rigorously analyzed for stability, and experimentally validated on the OctRobot-I platform.
Contribution/Results: The model accurately predicts shape-locking thresholds and stiffness-gradient responses, achieving a mean absolute error below 9.2%. It bridges a critical theoretical gap in control-driven dynamic modeling for LJ-type robots, enabling physically grounded, real-time stiffness-deformation co-regulation.
📝 Abstract
Continuum robots with variable stiffness have gained wide popularity in the last decade. Layer jamming (LJ) has emerged as a simple and efficient technique to achieve tunable stiffness for continuum robots. Despite its merits, the development of a control-oriented dynamical model 1 tailored for this specific class of robots remains an open problem in the literature. This paper aims to present the first solution, to the best of our knowledge, to close the gap. We propose an energy-based model that is integrated with the LuGre frictional model for LJ-based continuum robots. Then, we take a comprehensive theoretical analysis for this model, focusing on two fundamental characteristics of LJ-based continuum robots: shape locking and adjustable stiffness. To validate the modeling approach and theoretical results, a series of experiments using our OctRobot-I continuum robotic platform was conducted. The results show that the proposed model is capable of interpreting and predicting the dynamical behaviors in LJ-based continuum robots.
