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TIRAS Transactions on Intelligent Robotics and Autonomous Systems An open access journal of Kaggleyes Academy
TIRAS > Vol. 1, No. 2 (August 2026) > KAGG:2608.00007
Vol. 1, No. 2 (August 2026) — Article KAGG:2608.00007

How Much Future Range Do You Need? An Ablation Study for Agile Quadruped Navigation

Authors: Minju Seo, Junho Kang, Hyesun Bae

Legged Locomotion and Control Lab, KAIST, Daejeon, South Korea

[Received 2026-07-31; accepted 2026-08-11; published online 2026-08-14]

Abstract:

Future-range predictors estimate how far a legged robot can travel along control-aligned directions within a prediction horizon H, but the horizon is usually fixed by hand even though the appropriate look-ahead depends on speed and terrain. In a systematic ablation with the full navigation stack held fixed, the horizon (0.25, 0.5, 1.0, and 2.0 s), the query density, and the number of control-aligned directions are varied for a simulated Unitree Go2 in Isaac Lab across 12 scene families, speeds from 1 to 5 m/s, and flat, mixed, and rough terrain. From these results, a lightweight rule is fitted that selects the horizon from the commanded speed and an online terrain estimate, and the rule is then run on a physical Go2. In the simulated main comparison, the selected rule reaches a 92.3 percent success rate, compared with 81.1 percent for the best fixed horizon and 80.9 percent without future range, while maintaining a mean speed of 3.30 m/s. In the horizon sweep, success peaks at H = 0.5 s and declines for shorter and longer horizons; long horizons are most harmful on occluded turns at 4 m/s, where H = 2.0 s produces 4.7 braking events per km. The rule adds 0.4 ms of decision latency, and on hardware it selected horizons between 0.5 and 1.0 s in 8/8 recorded runs. The fixed-horizon entries are not consistent across the recorded tables, and in the sweep the rule matches but does not exceed the best fixed horizon.

Journal: Transactions on Intelligent Robotics and Autonomous Systems (TIRAS)
Volume / Issue: Vol. 1, No. 2 (August 2026)
Article ID: KAGG:2608.00007
DOI: 10.5803/kagg.2608.00007
Received: 2026-07-31
Accepted: 2026-08-11
Published online: 2026-08-14
License: CC BY 4.0

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Cite this article Minju Seo, Junho Kang, Hyesun Bae, "How Much Future Range Do You Need? An Ablation Study for Agile Quadruped Navigation," Transactions on Intelligent Robotics and Autonomous Systems, 2026, vol. 1, no. 2, KAGG:2608.00007. DOI: 10.5803/kagg.2608.00007.