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FACTR 2 (announced 11 June 2026 by @pathak2206 / JasonJZLiu with @StevenOh_ and…

Brief

FACTR 2 (announced 11 June 2026 by @pathak2206 / JasonJZLiu with @StevenOh_ and @_tonytao) makes commodity robot arms force-aware without dedicated sensors by learning a Neural External Torque (NEXT) model and applying Force-Informed Re-Sampling Training (FIRST). NEXT trains in under 1 minute with under 10 minutes of data to enable force-feedback teleop, higher-quality demos, more data-efficient BC, and strong performance on complex tasks with fewer demos or even no pretraining.

Source evidence

Force is arguably the most overlooked ingredient in modern robot learning.

Introducing FACTR 2: it turns any commodity robot into a force-aware system with no force sensors required.

Train a tiny force network in <1min with <10mins of data and drop it into any existing teleop pipelines:

✅ Free force sensing for both the robot and the operator arm
✅ Makes demos higher-quality → fewer of them needed.
✅ A new force-aware learning algorithm (FIRST) uses those recovered forces to figure out which parts of a demo actually matter, making learning data-efficient.
✅ Strong performance on complex tasks with fewer demos and even no pretraining!

More details below.

Video

Jason Liu (@JasonJZLiu)

💥Introducing FACTR 2, learning external force sensing on commodity robot arms without needing dedicated sensors.

We show that learned force signals enable force-feedback teleop on low-cost arms and improve BC policies.

FACTR 2 consists of:
1. Neural External Torque (NEXT): learns external forces without needing dedicated force sensors.
2. Force-Informed Re-Sampling Training (FIRST): uses the learned force signal to identify task-critical regions and upsample them during training.

w/ @StevenOh_ @tonytao

🧵(1/N)

Video

— https://nitter.net/JasonJZLiu/status/2065067670819500422#m