An open-weights whole-body motion tracker for a small humanoid, trained from scratch on one GPU
AspireAI community · arXiv
SONIC-K1 adapts the SONIC motion-tracking framework to the Booster K1 humanoid, which the authors describe as the first open-weights whole-body motion tracker for that platform, and trains the policy from scratch on a single shared GPU using a small fraction of the compute reported for SONIC. In MuJoCo simulation it tracks nearly all held-out motion clips and performs well on external benchmarks under SONIC's success criterion. On the real K1 robot it tracks upper-body and slow motions reliably, while stepping and turning remain less reliable, and simulation experiments show sensitivity to action latency. The authors name quantitative hardware evaluation as the main next step. Code, policy weights and evaluation tools are published.
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