This doesn\'t seem awfully intelligent. Considering that it will be highly dependant on the mass of the vehicle they\'re going to get destroyed by trucks and busses, motorcycles are going to have to slow down for them no matter what, because they won\'t be heavy enough to trigger it.
On top of all that, because it will have to be made of a flexible bladder that would also mean that it will be slippery, if not when dry then certainly when wet which means that there will be something on the road to disrupt braking and steering in an actual emergency.
11th February, 2010 @ 9:41 p.m. (California Time)
Yeah, and this will last one winter here on the east coast of the United States! I can\'t imagine this surviving the blizzard we have just dug ourselves out of!
12th February, 2010 @ 3:08 p.m. (California Time)
I have no connection to this idea, but I\'ve noticed a phenomenon that might be it. It\'s far from intuitive to get this. If I do get it right, it\'s NOT a weight dependent thing, but a completely soft bag with a thin fluid in it. The only thing preventing a childs bike from compressing it completely, would be the limited softness of the bag and cover, not at all the fluid inside.
Some fluid solutions behave strangely. If you pour them or stir them slowly, they appear thin as water. If you impact them, they feel more like hard rubber. It\'s only the speed that makes the difference. You can easily put your flat hand to the bottom of it, as long as you do it relatively slowly. It you stab it hard with the tip of a knife, you will no way get deep into it. The harder you stab, the sooner it stops.
You can try this out yourself with a cup of water and a few spoons of for example potato flour. Mix quite a bit of the flour into the water. Stir it well while mixing it in little by little to avoid lumps. (This ability may come in handy if you want to cook food for someone you like, but I\'d think of a different \"food\" than this). Do not make it become thick.
You\'ll feel the mentioned effect if you stir it rapidly. Remember: It will be runny, almost as normal water (but white) but if you really attack it, that\'s totally different. If you do use a cup, I\'d be a bit careful in the beginning. Apart from destroying utensils and splashing goo all over, you may also hurt yourself if you go for the knife test I mentioned. Make the solution a bit too thick first maybe, and then gradually dilute it to se the more extreme sides of it.
And eeeeh... No. I have no idea of why and how this works, physically. Probably no mystery. And by the way: Do not blame me for any mishaps you may provoke by testing! :-)
But of course Drew and Ed, there are valid reasons to wonder if it would work in real life. Bikes would be no problem as they can go on the side of the \"bump\" if they wish to go fast, as they frequently can on speed hump designs used now. But durability? Well, it seems like a real challenge. I guess freeze would be no big problem. Water and potato flor is most likely not the actual fluid, but I guess some anti freeze fluid would fix even that. Being a Norwegian, I\'m used to snow. I think it would be close to impossible to make this functional, but still able to tolerate snow plows scraping over them all winter.
But of course, not all ideas work everywhere. This may be useful in areas where snow is not a normal thing. In Norway we all easily walk on water, without at all relating that to being anybody mentioned in the Bible. At the same occations we like to use a fun invention called ice skates. :-) This invention is of course not very useful in Hawaii, even though they do have water there.
13th February, 2010 @ 11:10 p.m. (California Time)
it\'s unrealistic to think that the designer has come forward with the \"one size fits all\" approach. What i can gather from the description is that each bump would be tuned for each specific environment (in relation to weights and weather). This doesn\'t seem like it would be appropriate to mass apply this product but its defiantly a step forward in thinking and supporting emerging technologies, i\'d love to see what will come of this, seems like a great idea.
14th February, 2010 @ 2:02 p.m. (California Time)
\"non-Newtonian Thixotropic fluids\"
Even Wiki has a write up Drew and Ed.
Please leave your ignorance at the door and wipe your feet before treading on Bryce Killen\'s fine, hardwood floor of intelligence.
Stein has it sorted, it\'s the speed (of moving the fluid) which affects it\'s properties.
(top post Stein)
Drew since when does a flexible bladder have to be slippery when wet?
As opposed to that wonderful grip laden wonder material \"paint\" they liberally apply to EVERYWHERE on the road?
14th February, 2010 @ 5:46 p.m. (California Time)
Stein, a good example of a Thixotropic fluid that is also good fun to play with is combining corn starch and borax solution, the resulting solution will self syphon, behave as a solid when impacted and flow when not put under great stress.
The issue is though, that the material has to be tuned to a certain rate of displacement, because it doesn\'t behave as a specifically on/off mechanism it will tend to behave as a proper fluid only at very low shear loads, which means that whatever pumping mechanism give it its intial shape could not involve any type of orifice or restriction otherwise the behaviour of the material would be highly impact energy dependant rather than solely speed dependant.
The issue still stands of course, that any thixotropic materials bahaviour is only dependant on the shear force applied, which will naturally be higher with higher mass vehicles etc. which would require them to slow down further than light vehicles and then below a certain threshold a vehicle would not have the mass to pump the fluid out of the way without significant ride input even in its \"low viscosity\" state. This would lead to a \"mass optimised\" behaviour as I elluded to before.
Craig, although it does seem that you have a limited grasp of physics you do seem to have adequately outlined one issue with the system in a way that I obviously hadn\'t been able to. Yes, it will be very like painting yet another road feature, which will make it slippery when wet. And Craig, if you\'d like to provide an example of a tough and wear resistant bladder which will survive constant flexing but is not slippery when wet please also feel free to provide that when you reply again (assuming you do).
Another consideration you might want to give to similar designs in future is that these are typically produced by product design \"engineers\" who are people who typically undertake what is effectively a fine arts degree with a smattering of the more basic engineering so that they understand the language.
Quite frankly I view Product Design Engineers as an insult to my profession for the reason which is aptly illustrated by this concept, lack of basic engineering understanding.
15th February, 2010 @ 2:28 a.m. (California Time)
I don\'t think there is any need for thixotropic liquids. Imagine a rubber bottle, with a hole in the cap. Squeeze the bottle, and the air escapes. Stop squeezing, and the bottle sucks back the air. Now jump on the bottle and the air cannot escape fast enough and appears to be hard. That ought to work. By the way, if it was filled with thixotropic liquid, imagine the mess if it burst! I have just thought: Speed bumps don\'t work in snow, although snow does! Speed bumps are a damn nuisance, so in England they are trying out a much cheaper method of speed control. They have just let the road surfaces deteriorate to such an appalling state, with potholes every few yards(or feet in some cases) that it is downright dangerous to drive faster than 20mph, so you have to slow down or risk ruining your suspension.
15th February, 2010 @ 8:52 a.m. (California Time)
As soon as I secure my tenure I\'ll post that \"magic\" material.
But in the mean time as Ludwig Gauckle. He\'s swiss, good fella.
Not slippery when wet?..... as soon as they make the road not slippery when wet I suppose. To be AS slippery as the road when wet, probably not a problem, or at least as slippery as paint even easier, seeing as most speed bumps are painted... hmmmm..... hey I know! Paint them! Well that was easy. It\'s now just as slippery as any other speed bump. Oh and if you\'re going the correct speed and it moves out of the way for you... your suspension isn\'t being punished which allows it to function correctly and you can stop faster! Oh... well that\'s just neat.
So now it\'s just down to tuning them and finding a hardy material.
What flexes millions of times during its life..... can hold the weight of a car...... is commonly available.......sounds \"magical\" ;)
15th February, 2010 @ 4:17 p.m. (California Time)