# KAIST quadruped robot RAIBO2 completes marathon without battery swap, ~40 miles per charge

- Source: Singularity Hub
- Published: 2026-09-29T20:19:08.000Z
- RoboHot: https://robohot.news/en/items/nryh6gs4r8oolx7aevalbk53l
- Original: https://singularityhub.com/2026/09/29/this-robot-dog-crushed-a-marathon-without-stopping-to-recharge/

## Summary

KAIST's quadruped robot RAIBO2 finished the Persimmon Marathon in Sangju, South Korea, in 4 hours 19 minutes 52 seconds, slightly faster than the human average, without swapping or recharging its battery, and still had 34% charge at the finish; the team described the work in a Nature paper last week.

## Why it matters

The research moves energy saving for legged robots from optimizing single components to holistic design across joints and circuits, offering concrete methods transferable to long-duration outdoor robots.