How do you construct a safety case for an autonomous driving system?

Safety case construction: 1) Safety goals derivation from hazard analysis (HARA) identifying risks from system behavior or malfunction; 2) Functional safety requirements per ISO 26262 addressing systematic and random hardware failures; 3) SOTIF (Safety of Intended Functionality) per ISO 21448 addressing perception limitations and behavioral insufficiencies; 4) Argumentation structure (Goal Structuring Notation, Claims-Arguments-Evidence) demonstrating goal achievement; 5) Evidence collection - design verification, simulation results, testing coverage, field operational data. Challenges include: Quantifying rare event safety (10^-7 to 10^-9 failures/hour), demonstrating completeness of scenario coverage, and handling edge cases. Safety case is living document updated through development and operation. Third-party assessment often required for certification.