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by MereInterest 2321 days ago
Reading through the crash test procedure, it is astounding how little attention is paid to pedestrians.

1. Front crash test. Procedure: Crash car into stationary barrier at 35 mph. Is also applicable to face-to-face crash with car of same size, going at same speed.

2. Side crash test. Procedure: Slam concrete block into side of stationary car at 38.5 mph.

3. Side pole test. Procedure: Drag car sideways towards a pole.

4. Rollover resistance. Procedure: Compare the cars footprint to the height of the center of gravity.

The biggest thing to notice is that not one of these metrics involves pedestrians. Metrics 1-3 can be easily improved by making a bigger car, elevating the passengers and providing more crumple room. Metric 4 is unaffected, as the track width is increased to compensate.

If a low sedan hits a pedestrian, the pedestrian rolls over the car, having a lower impulse given over a longer period of time. If a high SUV hits a pedestrian, the pedestrian is knocked back, having a higher impulse given over a shorter period of time. Safety ratings need to account for the danger cars pose to others.

Source: https://www.nhtsa.gov/ratings

Source (SSF): https://www.safetyresearch.net/rollover-stability

2 comments

European safety rating has a category for "Vulnerable Road Users":

https://www.euroncap.com/en/results/tesla/model-3/37573

> Reading through the crash test procedure, it is astounding how little attention is paid to pedestrians.

In the U.S. at least, pedestrian safety concerns mainly affect prescriptive legislation (i.e. no pop up headlights). Some countries and blocs have testing similar to crash tests, but I'm not really sure how effective something like that is: any meaningful standard would need to have exceptions for different categories of vehicle. Though honestly I can't see that much can be done about pedestrian safety once your vehicle is colliding with a human being.

This a trap we all fall into. Because you are smart but don't understand that a thing could exist, doesn't mean it doesn't. We often use this crutch when absolving someone else of an action taken or a design flaw. "I would have never thought of that!" or "How could someone have anticipated that?"

> I can't see that much can be done about pedestrian safety once your vehicle is colliding with a human being.

https://en.wikipedia.org/wiki/Pedestrian_safety_through_vehi...

"Though honestly I can't see that much can be done about pedestrian safety once your vehicle is colliding with a human being."

I don't agree, there some definitive choices in car design that affect the aftermath of the collision that can have effect on the pedestrian surviving. As pointed above if a pedestrian is hit by a car he has a better chance to roll over the hood of the car vs an SUV where the pedestrian would probably would be hit and fall under the car.