Faster Visuomotor Policy Learning on Action Manifolds via Riemannian MeanFlow
S. Talha Bukhari, Austin Garrett, Yi Wei, Ruiqi Ni, Zachary Kingston, Aniket Bera · N/A · 2026
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Summary
Visuomotor policies learn a direct map from raw sensory observations to robot action sequences. Policies based on Diffusion and Flow Matching capture the multimodal distribution over action sequences in an end-to-end manner.
Abstract Summary
Key Points
- Visuomotor policies learn a direct map from raw sensory observations to robot action sequences
- Policies based on Diffusion and Flow Matching capture the multimodal distribution over action sequences in an end-to-end manner.
- This expressivity comes at the cost of multi-step numerical integration of the learned vector field for action generation, which can be expensive and time-consuming, impeding fast control rates required in robotics applications.
- Furthermore, robot action sequences are usually defined on a smooth, differentiable manifold, requiring that the learned policy respects the intrinsic geometry of the robot's action space.
- Here, we present Riemannian MeanFlow Policy (RMFP), which learns the conditioned flow map of the probability path on the robot action manifold.
Methodology
The action space of a manipulator is a smooth manifold rather than a vector space. Let $\mathcal{A}$ denote the manifold of a single action, which for an end-effector controller is the product $\mathcal{A}=\mathbb{R}^{3}\times\mathcal{S}^{3}\times\mathbb{R}^{2}$ of a position, a unit quaternion and two finger positions [ 2 ] .
Experiments
We ask whether a learned action flow map on a Riemannian manifold retains task performance at a limited sampling budget under different settings. We evaluate the proposed formulation against baselines for Riemannian generative policy learning on four simulated benchmarks and one trajectory-reproduction task. We use four simulated benchmarks (cf. Fig. 3 ) and one trajectory-reproduction task (cf. Fig.
1 ) that separate the effect of the training objective from the effect of the geometry of the action space.
Sources and Demonstrations
Figures are reproduced from Bukhari et al. See the full paper for experimental details and the project page, when the paper links one, for demonstrations and videos.
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