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invalidatoryesterday at 12:09 AM1 replyview on HN

It's not the same.

For a simple example, let's say you are simply driving in a circle. The car wants to lean toward the outside. The linear motors can provide a countering force, lifting the outside, lowering the inside, so the car stays level. Variable damping can only control the rate that it rolls. It will still roll in sub-second timescales, unless it completely locks down the suspension, which is terrible for both handling and comfort.

For another simple example: going over a speed bump. Linear motors can lift the front wheels over the bump, and then the rear wheels, so the body stays level the whole time. An active damper can go full-soft the moment the wheel hits the bump, but the compressed spring will still start lifting the front of the car. An active damper can do a better job managing the rebound on the far side so it doesn't oscillate, but it can't entirely prevent the bump from pitching the body up and down in the first place.

That's not to say it's worthless. Very fast active dampers can improve both handling and comfort. It's just nowhere near the level which is possible with linear motors.


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appreciatorBusyesterday at 1:22 PM

This is my biggest fear of technologies like these.

The whole point of a speed bump, for example, is to ensure that behaviour that puts others at risk will, at the very least make the driver uncomfortable. If we then deploy technologies that make speed bumps “disappear” from the perspective of vehicle occupants, it’s going to enable people to comfortably drive a lot more aggressively at the expense the people on the other side of the windshield.

Conversely, if we were to deploy technologies like speed governors, then we could do away with the speed bumps and the need for fancy suspension.

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