https://defencemachine.com/ Engineering notes on uncrewed and autonomous systems: autonomy stack design, human-on-the-loop authority as a timing specification, degraded and GNSS-denied operation, and coverage arguments for behaviour you cannot exhaustively simulate. en https://defencemachine.com/testing-what-you-cannot-enumerate/ https://defencemachine.com/testing-what-you-cannot-enumerate/ Mon, 20 Jul 2026 00:00:00 +0000 Test and evaluation Structural test coverage says nothing useful about an autonomy stack. What replaces it: a stated operating domain, directed falsification against a margin function, runtime monitors simple enough to test, and decisions you can reconstruct. https://defencemachine.com/who-holds-the-veto/ https://defencemachine.com/who-holds-the-veto/ Mon, 29 Jun 2026 00:00:00 +0000 Authority Human-in-the-loop and human-on-the-loop are usually written as policy. They are timing claims, and they only hold if the notification lead time exceeds the operator's response distribution. https://defencemachine.com/lost-link-is-not-a-boolean/ https://defencemachine.com/lost-link-is-not-a-boolean/ Mon, 08 Jun 2026 00:00:00 +0000 Degraded operation Datalink and satellite navigation fail gradually, asymmetrically and reversibly. Autonomy stacks that model them as a single flag inherit mode thrash, stale-data trust and unbounded dead-reckoning drift.