BEAST: Efficient Tokenization of B-Splines Encoded Action Sequences for Imitation Learning

Fuente: arXiv
Guardado en:
Detalles Bibliográficos
Autores principales: Zhou, Hongyi, Liao, Weiran, Huang, Xi, Tang, Yucheng, Otto, Fabian, Jia, Xiaogang, Jiang, Xinkai, Hilber, Simon, Li, Ge, Wang, Qian, Yağmurlu, Ömer Erdinç, Blank, Nils, Reuss, Moritz, Lioutikov, Rudolf
Formato: Preprint
Publicado: 2025
Materias:
Acceso en línea:
Etiquetas: Agregar Etiqueta
Sin Etiquetas, Sea el primero en etiquetar este registro!
_version_ 1866917038222475264
author Zhou, Hongyi
Liao, Weiran
Huang, Xi
Tang, Yucheng
Otto, Fabian
Jia, Xiaogang
Jiang, Xinkai
Hilber, Simon
Li, Ge
Wang, Qian
Yağmurlu, Ömer Erdinç
Blank, Nils
Reuss, Moritz
Lioutikov, Rudolf
author_facet Zhou, Hongyi
Liao, Weiran
Huang, Xi
Tang, Yucheng
Otto, Fabian
Jia, Xiaogang
Jiang, Xinkai
Hilber, Simon
Li, Ge
Wang, Qian
Yağmurlu, Ömer Erdinç
Blank, Nils
Reuss, Moritz
Lioutikov, Rudolf
contents We present the B-spline Encoded Action Sequence Tokenizer (BEAST), a novel action tokenizer that encodes action sequences into compact discrete or continuous tokens using B-splines. In contrast to existing action tokenizers based on vector quantization or byte pair encoding, BEAST requires no separate tokenizer training and consistently produces tokens of uniform length, enabling fast action sequence generation via parallel decoding. Leveraging our B-spline formulation, BEAST inherently ensures generating smooth trajectories without discontinuities between adjacent segments. We extensively evaluate BEAST by integrating it with three distinct model architectures: a Variational Autoencoder (VAE) with continuous tokens, a decoder-only Transformer with discrete tokens, and Florence-2, a pretrained Vision-Language Model with an encoder-decoder architecture, demonstrating BEAST's compatibility and scalability with large pretrained models. We evaluate BEAST across three established benchmarks consisting of 166 simulated tasks and on three distinct robot settings with a total of 8 real-world tasks. Experimental results demonstrate that BEAST (i) significantly reduces both training and inference computational costs, and (ii) consistently generates smooth, high-frequency control signals suitable for continuous control tasks while (iii) reliably achieves competitive task success rates compared to state-of-the-art methods.
format Preprint
id arxiv_https___arxiv_org_abs_2506_06072
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle BEAST: Efficient Tokenization of B-Splines Encoded Action Sequences for Imitation Learning
Zhou, Hongyi
Liao, Weiran
Huang, Xi
Tang, Yucheng
Otto, Fabian
Jia, Xiaogang
Jiang, Xinkai
Hilber, Simon
Li, Ge
Wang, Qian
Yağmurlu, Ömer Erdinç
Blank, Nils
Reuss, Moritz
Lioutikov, Rudolf
Robotics
Machine Learning
We present the B-spline Encoded Action Sequence Tokenizer (BEAST), a novel action tokenizer that encodes action sequences into compact discrete or continuous tokens using B-splines. In contrast to existing action tokenizers based on vector quantization or byte pair encoding, BEAST requires no separate tokenizer training and consistently produces tokens of uniform length, enabling fast action sequence generation via parallel decoding. Leveraging our B-spline formulation, BEAST inherently ensures generating smooth trajectories without discontinuities between adjacent segments. We extensively evaluate BEAST by integrating it with three distinct model architectures: a Variational Autoencoder (VAE) with continuous tokens, a decoder-only Transformer with discrete tokens, and Florence-2, a pretrained Vision-Language Model with an encoder-decoder architecture, demonstrating BEAST's compatibility and scalability with large pretrained models. We evaluate BEAST across three established benchmarks consisting of 166 simulated tasks and on three distinct robot settings with a total of 8 real-world tasks. Experimental results demonstrate that BEAST (i) significantly reduces both training and inference computational costs, and (ii) consistently generates smooth, high-frequency control signals suitable for continuous control tasks while (iii) reliably achieves competitive task success rates compared to state-of-the-art methods.
title BEAST: Efficient Tokenization of B-Splines Encoded Action Sequences for Imitation Learning
topic Robotics
Machine Learning
url https://arxiv.org/abs/2506.06072