cs.ROSep 5, 2026

Observation Design for Certified Control Authority: Projection--Estimability Separation and Active-Face Equivalence

Authors: Guangxi Wan, Hualong Du, Yuqi Liu, Qingwei Dong, Qingxin Li, Hongfei Bai, Peng Zeng

Organizations: State Key Laboratory of Robotics and Intelligent Systems, Shenyang Institute of Automation, Chinese Academy of Sciences, Shenyang 110016, China · University of Chinese Academy of Sciences, Beijing 100049, China

Abstract

A sound runtime admission gate executes only actions it can certify, and certifies only what its observations support. This paper asks how observations should be designed to maximize the set of actions that can be safely admitted, and shows the question is not a re-vocabulary of classical design problems. First, a projection--estimability separation: decomposing a constraint normal as c=cRange+cker⁡c=c_{\mathrm{Range}}+c_{\ker} relative to an information matrix, two-point discrimination along cc becomes arbitrarily reliable as the budget grows whenever cRange≠0c_{\mathrm{Range}}\neq 0, while robust admission of an action with normal cc is impossible at every budget whenever cker⁡≠0c_{\ker}\neq 0; such mixed directions are generic at any deficient rank, and at full rank the decoupling is bounded by the Kantorovich ratio and diverges with the condition number. Discrimination-optimal designs, being corner solutions of a linear criterion, land in exactly this regime. Second, an active-face equivalence theorem: the permissiveness-optimal design is LL-optimal for a target matrix generated endogenously by the action faces that become certification bottlenecks, weighted inversely by their remaining slack; single-face collapse recovers cc-optimal and goal-oriented design exactly, and a Caratheodory argument yields a bottleneck certificate of at most r(r+1)/2+1r(r+1)/2+1 faces. Around these we assemble exact certifiability per convex contract mode, for which κ≈3.29κ\approx 3.29 is derived rather than calibrated, the r\sqrt{r} price of contract-agnostic design, an information-to-slack transfer theorem with a curvature-budget corollary, and a two-part audit in which a design meeting every margin requirement still leaves an action face at a certification cost above ten times its testing cost, in every probe library tested.

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