DeformGen: Dynamics-Based Topology Augmentation for Deformable Manipulation Policy Learning

Imitation learning has achieved remarkable progress in robot manipulation, but its success heavily depends on large-scale demonstration data that are costly to collect. Recent work has therefore explored demonstration augmentation, but they are fundamentally limited in deformable manipulation, where task-relevant object variation is governed by high-dimensional deformations and physics-induced internal constraints rather than low-dimensional pose changes. We present **DeformGen**, a dynamics-based augmentation framework that achieves *topological diversity* for deformable objects. Instead of perturbing object pose, DeformGen expands the valid state distribution by applying localized physical disturbances, forward-simulating the dynamics, and stabilizing the result to obtain topology-coherent deformable states with physical plausibility. Given these synthesized states, DeformGen further transfers source manipulation trajectories via deformation-field warping, which lifts per-particle displacements into a continuous spatial function to adapt the end-effector trajectory consistently with the deformed geometry. In this way, our method augments both the state distribution and its associated manipulation behavior. Experiments on high-fidelity deformable manipulation benchmarks show that DeformGen consistently improves policy learning over training on the original demonstrations alone and over rigid-style augmentation baselines.