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Smarter speed bump using non-Newtonian liquid

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Re: Smarter speed bump using non-Newtonian liquid

#51

Post by jacquesm »

bfung wrote: post #24

Can someone enlighten me on why we need a smarter speed bump? If cars going too fast are going to be damaged either way, there's no benefits on that end. If the motivation is that cars can go slightly faster overall over the bump to reduce traffic... then don't put a bump there!?!? Slow traffic will still be slow?

Well, let me give you one reason why: Last year I got launched by a speedbump on my bicycle and broke my leg in six places. I could have really done without that given the fact that I wasn't exceeding the speedlimit and wasn't driving a car.

Re: Smarter speed bump using non-Newtonian liquid

#52

Post by agumonkey »

TomMarius wrote: post #48
runeks wrote: post #39

From the first video: > “Whether you respect the speed limit or not, your car will suffer from a speed bump regardless.” Can anyone confirm this? I would assume the suspension can handle speed bumps fine at low speeds. That’s what it feels like from inside the car anyway. Couldn’t it be argued that, as we approach a speed of 0 mph, there exists a speed at which no damage is done to the car whatsoever? And, if we plac…

You still have to brake (brake pads and discs suffer for no reason), gear down (transmission suffers) and potentially move off at a low speed (clutch suffers, your wallet suffers if you go over them frequently). Even at minimal speeds (less than 20 km/h), speed bumps feel very unpleasant and I really don't like sounds my car is doing while riding over them.

There are so many geometries (by design or error) .. but I remember that those that are more like a lifted platform with low angles are the one I like the most. I do slow down but I don't have to fear shocks. win win

Re: Smarter speed bump using non-Newtonian liquid

#54

Post by TomMarius »

ygra wrote: post #50
TomMarius wrote: post #48

Earlier quoted context omitted.

You still have to brake (brake pads and discs suffer for no reason), gear down (transmission suffers) and potentially move off at a low speed (clutch suffers, your wallet suffers if you go over them frequently). Even at minimal speeds (less than 20 km/h), speed bumps feel very unpleasant and I really don't like sounds my car is doing while riding over them.

Shouldn't speed bumps be designed that you move over them at the speed allowed there, e.g. 30 km/h? So theoretically there wouldn't be a slowdown, unless you're already going faster than allowed. At least I haven't seen speed bumps in 50 km/h roads just to slow people down.

Should, probably, but it's common in Central Europe that on a 50km/h road, there are 2 speedbumps that can't be safely passed if you're going over 25km/h.

Re: Smarter speed bump using non-Newtonian liquid

#55

Post by yjftsjthsd-h »

agumonkey wrote: post #53

Question I asked myself for years, why not use the idea in car bumpers. Maybe not fully loaded with fluids but non newtonian approach to shock absorption.

I would speculate that it's precisely because you don't want a car to be rigid on impact.

Re: Smarter speed bump using non-Newtonian liquid

#56

Post by DanBC »

jmdocherty wrote: post #5

This a really interesting idea. The problem of stabbing/puncturing can be solved by moving the liquid lower in the ground and having a floating more robust layer above. I imagine it would be particularly useful in places like outside hospitals where ambulances would prefer a smooth ride if possible. However, I'm sure we used to make a liquid with similar properties when we were children out of cornflower (?) and wate…

> I'm sure we used to make a liquid with similar properties when we were children out of cornflower (?) and water.

lots of people call this oobleck, and there are a gajillion of youtube videos about it.

Re: Smarter speed bump using non-Newtonian liquid

#57

Post by agumonkey »

yjftsjthsd-h wrote: post #55
agumonkey wrote: post #53

Question I asked myself for years, why not use the idea in car bumpers. Maybe not fully loaded with fluids but non newtonian approach to shock absorption.

I would speculate that it's precisely because you don't want a car to be rigid on impact.

You want a controled response curve. Something that gradually stiffens so the objects get slowed down as much as possible

Re: Smarter speed bump using non-Newtonian liquid

#58

Post by blackguardx »

amenod wrote: post #19
hirsin wrote: post #8

A student startup built something similar for potholes, which i think is a better use of the tech (1). Essentially road repair crews could carry a couple bags of the fluid and drop the bag into a pothole, where it would confirm to the shape of the hole while stiffening on impact from the tires. Unsurprisingly this was invented in Cleveland. 1. http://www.popsci.com/technology/article/2012-04/bouncy-thic...

> Unsurprisingly this was invented in Cleveland. For us uninitiated - why? Quality if the roads there?

Another commentor explained how potholes form, but I'll add that Cleveland doesn't have a lot of money and tends to defer maintenance.

When I was living there, road signs saying "Steel Plate on Road" were a common sight. I remember the city fixed a water pipe and instead of re-paving the street, they just left several giant 4ft x 8ft steel plates with corresponding sign for over a year.

Re: Smarter speed bump using non-Newtonian liquid

#59

Post by mcdonje »

amenod wrote: post #19
hirsin wrote: post #8

A student startup built something similar for potholes, which i think is a better use of the tech (1). Essentially road repair crews could carry a couple bags of the fluid and drop the bag into a pothole, where it would confirm to the shape of the hole while stiffening on impact from the tires. Unsurprisingly this was invented in Cleveland. 1. http://www.popsci.com/technology/article/2012-04/bouncy-thic...

> Unsurprisingly this was invented in Cleveland. For us uninitiated - why? Quality if the roads there?

Case Western Reserve University has a good engineering program.

Re: Smarter speed bump using non-Newtonian liquid

#60

Post by ChuckMcM »

Torkel wrote: post #43

Speaking to a founder to a competing company ( https://www.edeva.se/en/ ) I found out that there has been many attempts at solving the problems of speed bumps: - Everybody gets bumped, not only high speed vehicles - Emergency vehicles need to slow down - Bus drivers and others can get back problems from speed bumps Most solutions break down because the forces and the wear and tear is so tremendous. The solution from…

I've always wondered what it would look like to tie one of those roadside speed monitoring trailers (they have a sign telling you the speed limit, and your speed) which were in contact with a 'speed bump' filled with hydraulic fluid. The faster you go over the limit, the harder and taller the speed bump :-)

If you did this with a camera system you could avoid penalizing emergency vehicles.

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