Original title: R2S-Eval: Robot Evaluation with Real-to-Sim Calibration via Vision-Language Models
Yidi Wang, Feixiang Ruan, Ruoqu Chen, Jie Yin +3 · September 2026
Testing robot software in the real world is slow, exhausting, and often unhelpful. People have to reset objects by hand, watch every test, and run the same task again and again. These tests can give conflicting rankings and only score robots with a simple pass or fail, missing how well the robot actually moved. To fix this, researchers built a system called R2S-Eval. First, it tunes a computer simulator to closely match the real-world setup. The robot then runs its tests inside this calibrated simulation, creating videos of its attempts without wearing down physical machines. Next, an artificial intelligence that understands sight and language watches these video clips, compares pairs of robot attempts, and ranks which behavior is better. The team found that R2S-Eval saves massive physical effort, matches human judgments, stays stable across tests, and spots movement quality differences that pass-fail scores completely miss.
Imagine judging a cooking contest by watching video clips instead of eating the dishes live. Tasting each plate would take time and depend on the judge's personal taste. Here, the system creates simulated videos of robot actions and uses an AI to compare them, similar to judging by visual performance.
This makes robot testing cheaper and more reliable by replacing repeated physical trials with simulated videos. Researchers and engineers get clearer insights into how well robots actually perform, beyond just pass or fail.
The abstract does not explicitly state limitations, but the work is demonstrated in specific simulation and real-world settings for robot manipulation tasks, and it may still require some real-world calibration and validation.
Ask anything about this paper. Answers come from its abstract, and say so when the abstract doesn't cover your question.
R2S-Eval: Robot Evaluation with Real-to-Sim Calibration via Vision-Language Models — Yidi Wang, Feixiang Ruan, Ruoqu Chen et al.
Abstract licence: CC0
Explanation generated by Synthesis from the abstract — it is not the original paper. This is a preprint, so it hasn't necessarily been peer reviewed.