[4] Video tear down and analysis of how two versions of a Tesla external door handle assembly operate. https://youtu.be/Bea4FS-zDzc?t=278
In [1], the standard appears to be concerned primarily with preventing external intrusion of a vehicle and making sure door latches and hinges won't easily pry apart. It's _very_ lightweight on requirements. No wonder vehicle manufacturers at examples of [2] and [3] have to ask even the most basic questions about underspecified car door, latch and locking mechanisms.
From what [4] shows, Tesla external door handles have a default position of recessed (inaccessible) due to use of a spring. Hence if the car loses power (accident cuts wiring loom etc) or there is another control system or electrical fault, the external door handle defaults to being inaccessible. Further, the door handle assembly does not appear to contain a local controller so the wiring loom between the door handle assembly and controller elsewhere in the vehicle becomes safety critical. Control and power wiring looms also appear to have no redundancy to door handle assemblies. The only redundancy which appears to be possible, _may_ be, depending on failure mode such as cut to a wiring loom for one door only, trying to open another door.
From a quick search, it appears the school of thinking in the past has been in a vehicle impact where occupants inside are unable to escape, it's assumed doors and door frames are crushed and cannot be opened anyway until emergency services arrive and pry/cut them open.
From a safety engineering perspective, particularly in relation to vehicle fires, external doors should have a default mechanical position of unlocked/openable and only lock under positive control and power of the vehicle. Ideally there would be a mechanical circuit breaker designed too which cuts power to door handle/latch assemblies in the event of vehicle impact, causing them to automatically unlock. There are a few problems though--battery drain to keep the doors locked when the car is idle and external tampering to trick the vehicle into unlocking doors and providing access to thieves (in my view not an important requirement--just don't store valuables in vehicles).
Some relevant information:
[1] Federal Vehicle Safety Standards (US) ยง 571.206 Standard No. 206; Door locks and door retention components. https://www.ecfr.gov/current/title-49/subtitle-B/chapter-V/p...
[2] Interpretation of standard 206 mentioned above in relation to central electronic locking systems. https://www.nhtsa.gov/interpretations/11503wkm
[3] Interpretation of standard 206 mentioned above in relation to child safety door locks. https://www.nhtsa.gov/interpretations/11345wkm
[4] Video tear down and analysis of how two versions of a Tesla external door handle assembly operate. https://youtu.be/Bea4FS-zDzc?t=278
In [1], the standard appears to be concerned primarily with preventing external intrusion of a vehicle and making sure door latches and hinges won't easily pry apart. It's _very_ lightweight on requirements. No wonder vehicle manufacturers at examples of [2] and [3] have to ask even the most basic questions about underspecified car door, latch and locking mechanisms.
From what [4] shows, Tesla external door handles have a default position of recessed (inaccessible) due to use of a spring. Hence if the car loses power (accident cuts wiring loom etc) or there is another control system or electrical fault, the external door handle defaults to being inaccessible. Further, the door handle assembly does not appear to contain a local controller so the wiring loom between the door handle assembly and controller elsewhere in the vehicle becomes safety critical. Control and power wiring looms also appear to have no redundancy to door handle assemblies. The only redundancy which appears to be possible, _may_ be, depending on failure mode such as cut to a wiring loom for one door only, trying to open another door.
From a quick search, it appears the school of thinking in the past has been in a vehicle impact where occupants inside are unable to escape, it's assumed doors and door frames are crushed and cannot be opened anyway until emergency services arrive and pry/cut them open.
From a safety engineering perspective, particularly in relation to vehicle fires, external doors should have a default mechanical position of unlocked/openable and only lock under positive control and power of the vehicle. Ideally there would be a mechanical circuit breaker designed too which cuts power to door handle/latch assemblies in the event of vehicle impact, causing them to automatically unlock. There are a few problems though--battery drain to keep the doors locked when the car is idle and external tampering to trick the vehicle into unlocking doors and providing access to thieves (in my view not an important requirement--just don't store valuables in vehicles).