Neural Descriptor Fields:
SE(3)-Equivariant Object Representations for Manipulation


Anthony Simeonov*, Yilun Du*, Andrea Tagliasacchi,
Joshua B. Tenenbaum, Alberto Rodriguez, Pulkit Agrawal+, Vincent Sitzmann+

* Author contributed equally, order determined by coin flip.    + Equal Advising

Paper Code Colab

We present Neural Descriptor Fields (NDFs), an object representation that encodes both points and relative poses between an object and a target (such as a robot gripper or a rack used for hanging) via category-level descriptors. We employ this representation for object manipulation, where given a task demonstration, we want to repeat the same task on a new object instance from the same category. We propose to achieve this objective by searching (via optimization) for the pose whose descriptor matches that observed in the demonstration. NDFs are conveniently trained in a self-supervised fashion via a 3D auto-encoding task that does not rely on expert-labeled keypoints. Further, NDFs are SE(3)-equivariant, guaranteeing performance that generalizes across all possible 3D object translations and rotations. We demonstrate learning of manipulation tasks from few (~5-10) demonstrations both in simulation and on a real robot. Our performance generalizes across both object instances and 6-DoF object poses, and significantly outperforms a recent baseline that relies on 2D descriptors.

Results


As humans, we are able to naturally and easily manipulate a wide variety of different objects from a single demonstration, regardless of the underlying pose or instance of the object. Inspired by this capability, in this paper, we present a framework which can provably generalize a single manipulation demonstration of an object to an arbitrary novel pose of the object. Given a manipulation skill executed a upright mug, we may automatically apply this demonstration to the mug when it is oriented either sideways or even upside-down. We further show that our framework enables us to transfer demonstrations on different mugs to novel instances of a mug.

Paper


Bibtex


@article{simeonovdu2021ndf, title={Neural Descriptor Fields: SE(3)-Equivariant Object Representations for Manipulation}, author={Simeonov, Anthony and Du, Yilun and Tagliasacchi, Andrea and Tenenbaum, Joshua B. and Rodriguez, Alberto and Agrawal, Pulkit and Sitzmann, Vincent}, journal={arXiv preprint arXiv:2112.05124}, year={2021} }

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