🤖 AI Summary
Soft-bodied robot simulation faces dual challenges in modeling large deformations and complex contacts, with existing tools struggling to balance physical fidelity, computational efficiency, and control integration. This paper proposes a full-stack simulation and control framework grounded in discrete differential geometry. It features: (i) a fully vectorized NumPy implementation for high-performance computation; (ii) a penalty-energy-based implicit contact model unifying rigid–soft and soft–soft interactions; (iii) natural-strain-based PI feedback control; and (iv) modular coupling of energy models, actuation mechanisms, and machine learning components. Compared to the state-of-the-art Elastica library, our framework achieves a tenfold speedup while preserving comparable accuracy. It supports real-time trajectory tracking for rods, shells, and hybrid structures, and demonstrates robust sim-to-real transfer in experimental validation.
📝 Abstract
High-fidelity simulation has become essential to the design and control of soft robots, where large geometric deformations and complex contact interactions challenge conventional modeling tools. Recent advances in the field demand simulation frameworks that combine physical accuracy, computational scalability, and seamless integration with modern control and optimization pipelines. In this work, we present Py-DiSMech, a Python-based, open-source simulation framework for modeling and control of soft robotic structures grounded in the principles of Discrete Differential Geometry (DDG). By discretizing geometric quantities such as curvature and strain directly on meshes, Py-DiSMech captures the nonlinear deformation of rods, shells, and hybrid structures with high fidelity and reduced computational cost. The framework introduces (i) a fully vectorized NumPy implementation achieving order-of-magnitude speed-ups over existing geometry-based simulators; (ii) a penalty-energy-based fully implicit contact model that supports rod-rod, rod-shell, and shell-shell interactions; (iii) a natural-strain-based feedback-control module featuring a proportional-integral (PI) controller for shape regulation and trajectory tracking; and (iv) a modular, object-oriented software design enabling user-defined elastic energies, actuation schemes, and integration with machine-learning libraries. Benchmark comparisons demonstrate that Py-DiSMech substantially outperforms the state-of-the-art simulator Elastica in computational efficiency while maintaining physical accuracy. Together, these features establish Py-DiSMech as a scalable, extensible platform for simulation-driven design, control validation, and sim-to-real research in soft robotics.