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i bet the system also adds some extra weight to one's car.

i'm a fan of minimalist A arms set to extra firm myself. if i thought it could be done, i'd even design my imaginary lightweight (800lb) 1 seater buggy with no suspension to save weight & cost & let the tires do all of the shock absorption. if it works for skateboards (until you hit that one pebble anyways) i can't see why a rigid chassis couldn't be doable on a car. hardtail motorcycles have no rear suspension afterall.

i thought it would be interesting to design an EV where only the SEAT is suspended. using tires with a tall aspect ratio would help smooth things out although potholes could cause control issues at moderate speeds and really bumpy roads should be avoided, but most streets and highways are smooth enough.
 

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It seems to me that this could be some-what dangerous. It could be easier to underestimate how quickly you were going if you're used to a regular suspension. You probably also lose a lot of the gradual indicators. I imagine it continues to corner amazingly like that, right up to the point it flips over completely.

Making a car that has a skateboard suspension is fine... until you hit that pebble. :p The suspended seats is an interesting idea though.
 

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Hi. I haven't a clue as to how the Bose suspension works but it reminds me of a system I saw back in the early 90's that used servo motors to control the suspension. Their approach used the principle seen in a boat where the vessel leans in, toward the curve, and not against it like a car. Depending on speed and g-force, some of those old methods might prevent an unforeseen flip over.

JR
 

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It's the active suspenstion thing that has been so sought after by sports car manufacturers for many decades.
It can take a lot of processing power and fast response actuators to make it work well in all cases and not result in travel sickness or sudden and unexpected changes in the attitude of the car.

Lorry drivers have had access to air suspension seats for ages. Not sure it would work in cars given that there is so little headroom allowance.

In the UK suspension is a legal requirement of the C&U regs for anything powered that travels at more then 12mph (or is it 15mph) IIRC. It is one of the things that separates electric pedal bikes from motor bikes.
 

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active suspensions date back at least to the early 90s with porsche's insane limited edition 959 supercar (i think... the chubby silver 911)

i don't think tipping would be as much of an issue as hitting a 2 inch pothole or pressure crack & having it throw the car off it's line & causing it to crash.

check out the videos of that skinny little tango performing better in a slalom than a mazda i think. that car looks like it wants to tip over in a stiff breeze. my design would have a much wider stancewith low mounted batteries.

i wasn't planning on driving it hard daily, just at events like slaloms or drag races. i don't tip vehicles over. i jumped off a snowmobile that was towing my cousin in an inner tube playing "crack the whip" when i felt the left side start to lift. i ended up getting my leg caught in the tow rope and getting dragged a good 50 feet at least as well as listening to my cousin yelling at what a moron i am. so what happens next? he takes his cousin out and flips it & shatters the windshield & cowling doing the same exact thing. i don't push vehicles to their limits until i'm very familiar with them.

the suspensionless buggy is just a thought experiment. if there really were any merit in it, someone would have built one long ago. EVERY car has a suspension and for good reasons i'm sure.

i tell you though, i've never felt more nervous driving than when i pushed a former roomate's '72 ford torino with cool hide away headlights and a nice short stroke cleveland 351 motor to only 100mph on the highways when it starts bouncing & rolling like a baby carriage. i immediately backed off when it started doing that. i managed to get my 1 liter daihatsu charade up to 120mph comfortably on a mountain downhill though. that was one good little car. nothing ever went wrong with it over 100k miles whereas another roommate's chrysler that was 2 years newer with a fraction of the miles was in the shop monthly! they just never caught on in the US. it would be a great car for an EV conversion as i think the stock weight was something like 1,800 lbs. it could be easily pushed by one person. it didn't like going up steep hills though.
 

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Hey there. I'll pick one of the lines in your post to comment as you covered a lot in there. (I see you posted close to 4 AM and that can certainly screw my line of thought as well).

i don't think tipping would be as much of an issue as hitting a 2 inch pothole or pressure crack & having it throw the car off it's line & causing it to crash.
They show something similar in the video. This type of suspension measures how parallel the four ends are to the ground and adjusts pressure to each suspension column to compensate. I suppose we can question how quickly can the suspension react to that - or to a pothole - but I'd say pretty quickly. Certainly more effectively than sprung suspension.

Bose claims significant efficiencies in terms of power utilization but something tells me they're hyping that a tad. For one, the entire car is suspended by electric force all the time and that has to be costly. Absorbing the rebound of the pothole, as zeroermission was mentioning above, would take an enormous amount of power. Even if it uses a 1/4 of the power as similar systems, it's not showing up in EVs anytime soon.

JR
 

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I don't see how eliminating body roll could increase the chances of a roll over. If anything it would reduce the liklihood of that. Whats far more likely is the car would slide when it reaches the shearing limit of the road surface.

Great video BTW.
 
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