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TIRAS Transactions on Intelligent Robotics and Autonomous Systems An open access journal of Kaggleyes Academy
TIRAS > Vol. 1, No. 3 (September 2026) > KAGG:2609.00009
Vol. 1, No. 3 (September 2026) — Article KAGG:2609.00009

Adaptive Safety Margins for Quadruped Navigation with Calibrated Velocity Interfaces

Authors: Junho Kang, Hyesun Bae, Daewon Ryu, Minju Seo

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

[Received 2026-09-14; accepted 2026-09-25; published online 2026-09-28]

Abstract:

Fixed safety margins for legged navigation are tuned once, so they ignore both how well the robot's velocity interface is currently calibrated and how much free space the robot is about to enter. This paper presents an adaptive safety margin for quadruped navigation that combines the two signals. A calibrated interface model obtained with GAUGE supplies a high-confidence upper bound on the lateral deviation caused by command lag, and the control-aligned future-range predictor FutureRay supplies a lower confidence bound on the free range along the directions the controller can actually execute. The margin is the sum of a kinematic term and a lag-error term, each blended between its model-based value and its worst-case value by an explicit confidence weight. We prove that the margin is monotone nondecreasing in both uncertainty sources, that it never falls below the model-based bounds, and that it reduces exactly to the worst-case fixed margin when both confidences vanish. On a Unitree Go2 evaluated on 12 obstacle-adjacent segments at speeds from 1.0 to 4.0 m/s, with matching Isaac Lab simulation, the adaptive margin raises the collision-free speed from 3.10 m/s for the worst-case fixed margin to 3.40 m/s and task success from 78.4 to 90.8 percent, while lowering the 95th-percentile margin from 42.0 to 38.2 cm. When the interface model becomes stale after a payload change, the margin inflates toward the worst-case value without manual intervention.

Journal: Transactions on Intelligent Robotics and Autonomous Systems (TIRAS)
Volume / Issue: Vol. 1, No. 3 (September 2026)
Article ID: KAGG:2609.00009
DOI: 10.5803/kagg.2609.00009
Received: 2026-09-14
Accepted: 2026-09-25
Published online: 2026-09-28
License: CC BY 4.0

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Cite this article Junho Kang, Hyesun Bae, Daewon Ryu, Minju Seo, "Adaptive Safety Margins for Quadruped Navigation with Calibrated Velocity Interfaces," Transactions on Intelligent Robotics and Autonomous Systems, 2026, vol. 1, no. 3, KAGG:2609.00009. DOI: 10.5803/kagg.2609.00009.