Webots Demo 7: Testing a Supervisory Gate Pattern on TIAGo
Overview
A simulation explores a supervisory gate pattern for safety-critical robotics, using Webots and TIAGo in a hospital corridor. High-level planning runs as an untrusted proposer over non-blocking UDP, with cryptographic verification of 1,485 control cycles. An operator reset triggers a transition to RUN at 2.0 rad/s. The gate computes stopping distances with a margin for safety.
Generated from attributed reports · Updated 59 minutes ago
Event evidence and corrections
0 attributed source owners. Ownership does not establish independent confirmation. Quantities are reported separately and are never added together.
Reported quantity · hazard clearance threshold: 339 other · Basis not reported
“ate computes an envelope each tick: d_stop = ceil(v² / (2 * a_design)) + margin At 2.0 rad/s with a_design = 0.5 m/s² and a 300 mm margin, d_stop is 339 mm. If clearance falls below this, the gate overrides the proposer and commands 0.0 rad/s within a single 32 ms simulation tick. Recovery Contract & Latch: After a trip, the gate latches in TRIPPED. It requires a continuous 1.0s dwell of clear readings before an oper”
Exact source · revision 2Source owner not reported
Reported quantity · simulation tick duration: 32 other · Basis not reported
“ate computes an envelope each tick: d_stop = ceil(v² / (2 * a_design)) + margin At 2.0 rad/s with a_design = 0.5 m/s² and a 300 mm margin, d_stop is 339 mm. If clearance falls below this, the gate overrides the proposer and commands 0.0 rad/s within a single 32 ms simulation tick. Recovery Contract & Latch: After a trip, the gate latches in TRIPPED. It requires a continuous 1.0s dwell of clear readings before an oper”
Exact source · revision 2Source owner not reported
Reported quantity · simulation speed: 2 other · Basis not reported
“liberation fails, the gate clamps the motors, latches, and enforces a formal recovery contract before allowing any motion to resume. The Scenario: Hospital Corridor Transit I set up an illustrative healthcare logistics corridor in Webots (R2025a) with a PAL Robotics TIAGo base: TIAGo cruises down the corridor at a proposed speed of 2.0 rad/s (~0.196 m/s). An obstacle (a platform cart) sits in the active swept path at”
Exact source · revision 2Source owner not reported
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- ROS Discourse — Community updatesWebots Demo 7: Testing a Supervisory Gate Pattern on TIAGo (QERRA-v2 Classical)
This tutorial presents a simulation-based exploration of a supervisory gate pattern for safety-critical robotics systems, inspired by classical control architectures. It isolates high-level planning from low-level actuation using non-blocking UDP communication and enforces recovery contracts through latching and operator resets. The simulation uses Webots and a TIAGo robot in a hospital corridor scenario, with detailed logging and cryptographic verification of control cycles.
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