Non Newtonian Fluid.

Wouldn't you want the fluid in a shock absorber to have the exact opposite effect?

You have springs as well as shocks...
The idea behind the shock absorber is that it takes the shock.
The springs reduce the hit to give you a smoother ride, but, the shock absorbers resist the initial "hit", but then allow the springs to decompress at a slower rate after the initial shock so you dont get that bounce ...
On say a lump of brick in the road, no shock absorber, you "Bounce" upwards as the springs force the forward motion into upwards motion.
With shocks, they absorb the shock of the impact on the brick, and allow a slow movement of the suspension to "recover" as the vehicle either puts the wheel back down on the other side or changes ride height.

If the shock absorber is "too large" or too stiff, you get the kind of ride when if you run over a penny, you can tell heads or tails, some "M" class race replica type BMW's are cursed with that. Good road handling but bloody uncomfortable, like being kicked by an asthmatic donkey, not to bad a first but after a hundred miles?..
If the shocks are too small or too soft, you get the ride of the all American land yacht, that wallows about like a drunk elephant on rollerskates.

The ideal s something in-between, something that absorbs sudden impact for comfort but as a fast reaction to allow good road grip.

I have a set of Oil filled dampers for my two foot high two foot long R/C Monster truck ^{Gravedigger replica} here, I can alter the apertures inside the dampers by changing out the washers for ones with different sized holes, that alters the rebound rate, to allow either a hard or soft ride, if its doing higher jumps, I change out for larger holes to allow the springs to take the impact, if its doing flat race, I put on the smaller hole set to give firm suspension.
If you look at the steam hook arrester on the flight deck of an aircraft carrier, it sort of works in the same way.
The arrester gear that is on the working end of the cables, they are attached to a piston below deck, they can alter the holes in that piston to allow greater resistance, to allow greater stopping force for larger aircraft...
Think of the difference between braking a fast jet basic primary trainer, not a lot of weight, and then trying to stop a Hercules transport C130... the force needed to brake a C130 to a stop before it runs out of deck would snap the hook of a basic trainer?..
Therefore, they change the aperture that allows bypass of the piston.

The shocks on my R/C are full replica's of the basic technology behind suspension shock absorbers, and they are adjustable, they have intrigued me enough to find out how shock absorbers work, and that basic description above is mostly what the standard shock on a car is based on.
Technology changes... you now have electrical magnetics inside the shock that can alter the fluid density or change the compression rate, but thats all electrical, not available on all cars, just "expensive" ones.

The idea of the Non Newtonian fluid is, high impact gives greater resistance to initial impact but with enough force to compress the shock absorber anyway, and thats a sizing thing, if the shock is too large it wont push through the fluid, then at a slower rate, it easily allows a reaction to decompress the spring, so a faster reaction to put the wheel back in its normal driving position.

Of course this will produce a LOT of heat, so you may need to vent the shocks.

Downfalls of this.
If the fluid is "too thick", it will harden too much, and create a immovable object, and when the suspension becomes the part between that and a hard place, "sumfin' goina' break..."
Therefore, not a fully hard non Newtonian fluid, but one that allows some movement, but has a harder "grip" on faster shocks?.
The faster the shock, the firmer the grip?..
But quickly reverts to the slower speed to allow reaction of the spring to replace the wheel to "average" ride height...

If the shock is too large its going to "cook" inside before it can shed its heat.

I am wondering if you can by tinkering "Hit the sweet spot", whereby a soft compression would allow a full suspension travel slowly and comfortably, but a hard hit would resist the travel faster, transferring all the energy to heat, whilst still allowing the suspension to travel, but in both cases, would allow a fast reaction to reset the wheel back on the road.

Do you see what I am aiming for here?..

BTW, if this works, I want full acknowledgement as the "inventor" ... or did someone get here first?..

I see what you are aiming for, but I still think you have your gun wrong way 'round. as I see it, gentle movements, like your land yacht ride the shocks are going to give no resistance and your boat will never stop wallowing. hit that brick, and your fluid is going to try to turn into a solid and send ALL that impact straight through to your frame. basically, the harder the hit, the more energy it is going to not-absorb. what would seem more effective to me would be a hyper newtonian fluid, so when there is a lot of force on the shock, either from a big hit, or from having the springs very compressed, it moves quite easily, but as the force drops off, the fluid stiffens rapidly, preventing over travel. I could be totally wrong, but it seems to me non newtonian fluid in the shocks would get you the ride feel of the BMW with the handling of the land yacht.

now if you was talking some sort of progressive shock with non newtonian in the end of travel, so it would apply just enough resistance to stop the shock bottoming out all at once, I could see that. but then you is not carrying enough suspension travel if you do that, a lot.

that is a good way of looking at it. not 100% accurate as the shock absorbers absorb any shock they do not transfer to the springs - an in fact they dampen the oscillation by absorbing a greater or lesser portion of the shock, without the recoil that comes from the springs.

but it provides a working model.

and watch how fast the wheels move. now consider that the key property of non newtonian fluid is that it refuses to do fast.

perhaps, at that, a test is in order. I wounder how hard it would be for them to make homemade shock absorbers that they could fill with different mixtures - ranging from water to heavy cornstarch "mud"

put them on a buggy, with pressure transducers between the wheels and suspension, and G monitors in the seat of the pants, and run a short timed course to establish performance. (addendum: suspension travel monitoring, as well)

it would probably make interesting viewing.

That's why current high end suspension systems utilize sensors and computers and valves and variable size orifices. I'm sure that as soon as a "semi non-newtonial" fluid is invented, the shock absorber companies will be on it.