Humanoid Safe Stop via Learned Stoppability Value
- URL: http://arxiv.org/abs/2609.02358v1
- Date: Wed, 02 Sep 2026 09:29:39 GMT
- Title: Humanoid Safe Stop via Learned Stoppability Value
- Abstract summary: We propose a task-agnostic framework that pairs a learned stop policy with learned stoppability estimators.<n>The estimators are complementary: a stop-probability estimator supervised by the actual outcomes of the fixed stop policy, and a reach-avoidance estimator supervised by a Hamilton-Jacobi backup over physical state.
- Score: 61.25464390942355
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: Humanoid robots responding to emergency stop commands typically execute a fixed maneuver, without reasoning about whether a safe stop is actually feasible from the current state. We cast emergency stopping as a reach-avoid problem and propose Safe-Stop, a task-agnostic framework that pairs a learned stop policy with learned stoppability estimators. The estimators are complementary: a stop-probability estimator supervised by the actual outcomes of the fixed stop policy, and a reach-avoidance estimator supervised by a Hamilton-Jacobi backup over physical state. The first captures emergent stopping behavior of the learned controller; the second provides a complementary recoverability signal. Because the stop policy and estimators do not depend on the behavior policy that preceded the stop command, they transfer across diverse upstream tasks without retraining. At deployment, the two estimates are combined: Safe-Stop commits to the stop only when both estimators indicate that stopping remains feasible, otherwise it hands off to a fall policy, instantiated as a damping fallback. This agreement check yields decisions that are robust without sacrificing reactivity.
Related papers
- StochSIPP: Safe Interval Path Planning in Stochastic Dynamic Environments [5.420427804064936]
StochSIPP is an exact contingent planner for temporal roadmaps.<n>It generates certified-safe macro-actions that terminate at the next observation or the goal.<n>It minimizes expected arrival time within the roadmap and horizon.
arXiv Detail & Related papers (2026-08-01T17:49:37Z) - What Can Be Enforced? A Theory of Certified Runtime Safety for Tool-Using Agents [0.0]
guardrails act before irreversible tool calls, but their guarantees depend on what policy state is representable.<n>Pearson representation attacks add a margin, so benign calibration alone does not transfer.<n>Experiments target these distinctions through static diagnostics, controlled-model enumeration, representation rewrites, and paired closed-loop reruns.
arXiv Detail & Related papers (2026-07-24T19:14:26Z) - When Can Safe Controllers Adapt? Information before Commitment [26.556002437630426]
We study safe adaptive control under a safety guarantee on the learning trajectory itself.<n>Performance is measured against a safe oracle that knows the realized model.<n>We prove recovery in special cases and derive semidefinite upper certificates for deterministic linear-Gaussian systems.
arXiv Detail & Related papers (2026-07-18T17:30:41Z) - Action-Conditioned Risk Gating for Safety-Critical Control under Partial Observability [79.08785366532287]
We propose a lightweight risk-gated reinforcement learning approximation for risk-sensitive control under partial observability.<n>We evaluate the approach in two safety-critical partially observable domains: automated glucose regulation and safety-constrained navigation.
arXiv Detail & Related papers (2026-05-14T01:23:09Z) - Learning Safe-Stoppability Monitors for Humanoid Robots [11.850318870435265]
We formalize emergency stopping for humanoids as a policy-dependent safe-stoppability problem.<n>We introduce PRISM, a simulation-driven framework that learns a neural predictor for state-level stoppability.<n>Results show that modeling safety as policy-dependent stoppability enables proactive safety monitoring and supports scalable certification of fail-safe behaviors for humanoid robots.
arXiv Detail & Related papers (2026-03-24T01:51:32Z) - Pro2Guard: Proactive Runtime Enforcement of LLM Agent Safety via Probabilistic Model Checking [8.970702398918924]
Large Language Model (LLM) agents exhibit powerful autonomous capabilities across domains such as robotics, virtual assistants, and web automation.<n>Existing rule-based enforcement systems, such as AgentSpec, focus on developing reactive safety rules.<n>We propose Pro2Guard, a proactive runtime enforcement framework grounded in probabilistic reachability analysis.
arXiv Detail & Related papers (2025-08-01T10:24:47Z) - Centaur: Robust End-to-End Autonomous Driving with Test-Time Training [84.78837437133234]
We propose Centaur, which updates a planner's behavior via test-time training without relying on hand-engineered rules or cost functions.<n>We develop a novel uncertainty measure, called Cluster Entropy, which is simple, interpretable, and compatible with state-of-the-art planning algorithms.
arXiv Detail & Related papers (2025-03-14T17:59:41Z) - Criticality and Safety Margins for Reinforcement Learning [53.10194953873209]
We seek to define a criticality framework with both a quantifiable ground truth and a clear significance to users.<n>We introduce true criticality as the expected drop in reward when an agent deviates from its policy for n consecutive random actions.<n>We also introduce the concept of proxy criticality, a low-overhead metric that has a statistically monotonic relationship to true criticality.
arXiv Detail & Related papers (2024-09-26T21:00:45Z) - Safety Margins for Reinforcement Learning [53.10194953873209]
We show how to leverage proxy criticality metrics to generate safety margins.
We evaluate our approach on learned policies from APE-X and A3C within an Atari environment.
arXiv Detail & Related papers (2023-07-25T16:49:54Z) - Doubly Robust Off-Policy Value and Gradient Estimation for Deterministic
Policies [80.42316902296832]
We study the estimation of policy value and gradient of a deterministic policy from off-policy data when actions are continuous.
In this setting, standard importance sampling and doubly robust estimators for policy value and gradient fail because the density ratio does not exist.
We propose several new doubly robust estimators based on different kernelization approaches.
arXiv Detail & Related papers (2020-06-06T15:52:05Z)
This list is automatically generated from the titles and abstracts of the papers in this site.
This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.