LIFT: Force-Aware Post-Training Boosts VLA Policies for Contact-Rich Manipulation

Jul 17, 2026

Researchers introduce LIFT (Late Reactive Injection of Force for VLA Post-Training), a framework that enhances pretrained vision-language-action (VLA) policies by adding contact reactivity through a reactive action expert with force memory and cross-attention. By combining this with an online DAgger loop for training on both offline and human-corrected online data, LIFT enables faster learning and higher performance on contact-rich manipulation tasks such as towel folding and book insertion compared to vision-only post-training.

Why it matters: LIFT addresses a key limitation of vision-driven VLA policies by enabling more robust robot manipulation in scenarios involving occlusion or force-sensitive interactions, without sacrificing general manipulation knowledge.

Full story at: arXiv Robotics ↗