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I sat at a bus stop today and watched cars going over a speed hump, and had an idea that the conventional system of reactive ride stabilization could be obsolete, negating the need for springs, shocks, struts, everything. As far as I know the technlogy is already in place for other applications, including toys.
A car could have a sensor forward from the wheels, which would constantly monitor the distance to the ground. With each irregularity in street level, (popthole, frost heave, speed hump, loose rock, whatever), a signal could be sent to a firm axle, commanding it to retract slightly according to the change in the height of the road level, coordinated with the anticipated moment of impact. With this, a car could hit a speed hump (or even a curb) and 70 mph, and the occupants of the car would feel nothing.
Feel nothing? No. Feel less than they do today with conventional suspension? Sure.
Spring rates and shock damping can be controlled electronically. Many cars have had suspensions with adjustable shock damping for a long time. But they required you to choose "firm" or "comfort" with a switch. Now sensors can drive software to make that choice.
But for now these mechanisms can't neutralize the shock (the "slap") of the tire hitting the bump nor "lift" the wheel over a bump. Not saying it can't be done - lifting the wheel would require a mechanism to not just soften the spring rate but make it go negative.
I'd question - why does it matter so much? It doesn't to me - justify a ridiculous amount of electronics, hydraulics, and motors.
Mercedes has an active suspension on the newly released S class that uses a stereoscopic camera to read road imperfections and ready the suspension in advance which reportedly feels brilliant.
Bose did something along that exact line using processor adjusted linear motors to replace the struts, there may have been some conventional dampening in there as well not sure as they were pretty tight lipped on the exact details. Video is on YT somewhere features a modified mid 90's Lexus LS400 jumping over parking spot barricades and other on track testing, pretty impressive but it never went anywhere as far as I know for vehicle suspension. Bose later recalled the idea and incorporated the technology into a line of seats for HD equipment and tractor trailers. Interesting how you thought of that though!
More things to break. Magnetic damping is brilliant though, and has reached its engineering maturity on a large scale. I had PASM after being skeptical about it, and am now a true believer.
Power consumption becomes a concern. If you eliminate springs and dampers then you need an apparatus to constantly suspend the vehicle at each wheel, not only does it need to suspend but it will need to actively articulate the body at each point. Consider this [very] basic scenario: A 4000lb car, 1000lbs at each wheel. The vehicle encounters a defect in the road which requires 1 wheel to raise that portion of the vehicle 3 inches. Say we give it 100 milliseconds to perform the correction… which is a very slow reaction time for suspension; this requires about 3500 Watts, on a 12V system that is approaching 300 Amps. Consider that is only one wheel and one correction. This is one, large, reason why electronic systems only are in place to supplement conventional systems. If you eliminate conventional completely the system would need to react very slowly (less power), work with conventional systems (already exists), or have one heck of a power supply (not currently feasible). Of course there are many ways to also harvest power from suspension movement and use it for other wheels but ultimately you will need a means of exerting that power... things get very complicated and very costly, but they do exist.
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