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TIRAS Transactions on Intelligent Robotics and Autonomous Systems An open access journal of Kaggleyes Academy
TIRAS > Vol. 1, No. 1 (July 2026) > KAGG:2607.00003
Vol. 1, No. 1 (July 2026) — Article KAGG:2607.00003

Range-Gated Safety Envelopes for Reactive Quadruped Navigation

Authors: Anika Roth, Selin Aydin, Lukas Brandt

Robot Learning Lab, University of Zurich, Zurich, Switzerland

[Received 2026-07-03; accepted 2026-07-14; published online 2026-07-17]

Abstract:

Reactive navigation layers for legged robots commonly surround obstacles with a fixed inflation margin. Such a margin is conservative at low speed and can be unsafe at high speed, where velocity-controller lag lets the realized motion run past the point at which a command was judged safe. This paper proposes a range-gated safety envelope for reactive quadruped navigation. A configuration-based motion model, following the abstract robot configuration used by AgniNav, predicts the motion realized by each candidate velocity command under a bounded actuation delay, and the predicted free range along the planned direction is evaluated over the planning horizon. A command is admitted only if this predicted range envelope remains inside a speed-dependent corridor whose length and width grow with the worst-case stopping distance; otherwise the layer hands control to a braking maneuver. Under a bounded controller lag and a guaranteed braking deceleration, a certificate-style argument shows that every admitted command preserves the existence of a collision-free stop. The approach is evaluated in an Isaac Lab cluttered-corridor suite with doorway and stair-adjacent segments and on a Unitree Go2 traversing indoor hallways at setpoints from 1.5 to 4.0 m/s. Compared with a fixed inflation margin, the envelope raises collision-free success from 81.4 to 93.2 percent and mean speed from 2.70 to 3.05 m/s while reducing reaction overshoot from 14.2 to 12.8 cm. Ablations indicate that the controller-lag bound and range gating account for most of the gain.

Journal: Transactions on Intelligent Robotics and Autonomous Systems (TIRAS)
Volume / Issue: Vol. 1, No. 1 (July 2026)
Article ID: KAGG:2607.00003
DOI: 10.5803/kagg.2607.00003
Received: 2026-07-03
Accepted: 2026-07-14
Published online: 2026-07-17
License: CC BY 4.0

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Cite this article Anika Roth, Selin Aydin, Lukas Brandt, "Range-Gated Safety Envelopes for Reactive Quadruped Navigation," Transactions on Intelligent Robotics and Autonomous Systems, 2026, vol. 1, no. 1, KAGG:2607.00003. DOI: 10.5803/kagg.2607.00003.