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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:2608.00004
Vol. 1, No. 2 (August 2026) — Article KAGG:2608.00004

Safe Velocity Interface Identification Under Input Saturation

Authors: Siyuan Cui, Kaiwen Deng, Zhenghao Liu

Autonomous Systems Center, National University of Defense Technology, Changsha, China

[Received 2026-07-24; accepted 2026-08-04; published online 2026-08-07]

Abstract:

Active calibration of opaque quadruped velocity interfaces, as in GAUGE, issues planner-conditioned probe commands and fits a command-to-motion model online. Informative probes can push the robot toward the saturation boundary of the interface, where the response becomes nonlinear and potentially unsafe on rough ground. This paper adds a probe safety layer: each probe is admitted only if it keeps the robot inside a verified reachable-and-recoverable region computed from a conservative inner model, namely a linear command-response model valid below a certified saturation bound with uncertainty from a recursive least-squares confidence set. Probes are selected to maximize planner-weighted information subject to saturation, excursion, and recovery-time constraints, and the safety margin is derived from the same confidence set as the identification estimate, so the safe region expands as confidence grows. Under bounded-disturbance and inner-linearity assumptions, the analysis shows that the certified identification residual and the safety margin evolve jointly: the margin is nonincreasing, safety holds with high probability, and both quantities decay at the same rate under persistent excitation. In 120 simulated identification sessions on a Unitree Go2 in a cluttered course with an 8-degree slope, the method reached a 10.8 percent RMS identification residual versus 11.3 percent for unconstrained GAUGE-style probes, reduced the mean maximum excursion outside the safe region from 5.4 cm to 4.7 cm, and reached navigation-grade accuracy in 52 s instead of 60 s with smaller probes. In ten hardware sessions, a runtime monitor truncated one probe after a 0.04 m/s violation of the certified saturation bound.

Journal: Transactions on Intelligent Robotics and Autonomous Systems (TIRAS)
Volume / Issue: Vol. 1, No. 2 (August 2026)
Article ID: KAGG:2608.00004
DOI: 10.5803/kagg.2608.00004
Received: 2026-07-24
Accepted: 2026-08-04
Published online: 2026-08-07
License: CC BY 4.0

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Cite this article Siyuan Cui, Kaiwen Deng, Zhenghao Liu, "Safe Velocity Interface Identification Under Input Saturation," Transactions on Intelligent Robotics and Autonomous Systems, 2026, vol. 1, no. 2, KAGG:2608.00004. DOI: 10.5803/kagg.2608.00004.