This week my car was the unfortunate recipient of a glancing hit-and-run blow while parked. As often happens on the narrow streets of Seattle, some driver’s side-view mirror clipped mine and the result was the loss of the reflective glass.
What impressed me was how well the collision was handled by the mirror’s design. Like most modern cars, the side-view mirrors are on a soft-lock swivel so the majority of the impact was diffused by the mirror being pushed forward. Unfortunately that didn’t handle all of the force and the glass was gone when I returned to the car.
But take a look at the picture. Look at how clean the separation of the glass was. The mount-point (covered in that weird white grease) was undamaged. The various wires connected to the mirror (for the heater and blind-spot monitoring signal) also disconnected quite cleanly. While the replacement glass isn’t cheap, this is certainly better than a repair to the entire side-view mirror structure.
I don’t know if the mirror system was intentionally designed for this case, but the result is admirable. Imagine building systems with a focus on handling failure. Most of the sexy work is building the delightful parts of a product’s experience. For a car that might be the interior or the engine. There’s nothing sexy about a side-view mirror, but its design can exhibit a wide range of experiences in the face of failure. All things considered, I’m relatively pleased with the outcome.
I don’t yet know how to apply this in terms of application design in any concrete terms. Maybe, like many things in life, one can’t boil this down to some simple ”design pattern”. But I suspect there’s a real art and science to it which lies mostly below the waterline.