NORA-1.5: A Vision-Language-Action Model Trained using World Model- and Action-based Preference Rewards
🔥 Project NORA is supported by Gemini and Lambda Labs! We are thankful to them.
NORA-1.5 is a Vision-Language-Action (VLA) model that improves generalization and real-world decision making through post-training with world-model-based and action-based preference rewards.
The model builds upon the NORA foundation to achieve stronger instruction following, closed-loop control, and real-robot success, demonstrating reliability across LIBERO and SimplerEnv environments.
This repository consolidates the full open-source release of model checkpoints, inference code, training code, and evaluation tools, along with documentation and examples.
🌐 Project Website
🔗 https://declare-lab.github.io/nora-1.5
🚀 Key Features
- Vision-Language-Action architecture with enhanced task completion rate and distraction rate
- Action-based preference optimization using expert preference rewards
- World-model-based preference learning for improved planning and consistency
- Strong closed-loop control, enabling deployment in real robot settings
- Supports multi-task, long-horizon, and few-shot generalization
- Compatible with LeRobot, LIBERO, SimplerEnv, and custom environments
📦 Repository Structure (will update)
📆 TODO ~ 1 week
- Release the inference code of Nora-1.5
- Release all relevant model checkpoints(Pretrained, libero, SimplerEnv etc)
- Release the training/fine-tuning code of Nora-1.5 with LeRobot Dataset
- Release SimplerEnv evaluation code
Minimal Inference Sample (Will update)
from inference.modelling_expert import VLAWithExpert
model = VLAWithExpert()
model.to('cuda')
outputs = model.sample_actions(PIL IMAGE,instruction,num_steps=10) ## Outputs 7 Dof action of normalized and unnormalized action
Citation
@article{hung2025nora15,
title={NORA-1.5: A Vision-Language-Action Model Trained using World Model- and Action-Based Preference Rewards},
author={Hung, Chia-Yu and Majumder, Navonil and Deng, Haoyuan, Liu Renhang, Yankang Ang, Amir Zadeh, Chuan Li, Dorien Herremans, Ziwei Wang, and Soujanya Poria},
journal={arXiv preprint},
year={2025}
}