Motion Camoflage and SMIDSY!

[jambo]

Originally Posted by Balky001

I hire a lad to walk in front of the bike waving a big red flag. It seems to work but have difficulting getting him to run above 60mph!

The answer is a stick and rolerskates! just mount them about 6ft in front of the bike, they keep the wind off you too!


Balky001: I always ride with my headlight on for exactly that reason!

I saw this, interesting idea and if there is anything in it, it's useful to be aware of it.

I've been thinking for some time about the issue of SMIDSYs and was wondering if there could be something in it (apart from dumb car drivers.) Now, I'm not a mathmatician but here's a challenge for anyone of a mathematical bent. Is it possible that under certain conditions, a bike is invisible?

Let's say you're in a car sitting at a T-junction waiting to pull out. Let's also say you have a reasonable amount of clear road either side (say 30m) where you have an unobstructed view of approaching traffic. It would be fair to assume that under these conditions, you stand a 99.99% chance of seeing the articulated lorry coming towards you at 30mph. Because it is big and slow, you WILL see it in the time it takes to cross those 30m.

Now consider a car, smaller cross section so you presumably stand a slightly lower chance of seeing it under the same conditions. However, if the car reduces its speed, it takes longer to cross the same distance which counteracts its smaller profile so increasing your chances of seeing it e.g. you stand a 99.9% chance of spotting the car if it is approaching you at say 20 MPH.

Finally consider a bike, maybe it has 20% of the frontal cross section of the articulated lorry and so your chance of spotting it is correspondingly lower. Does this mean that to stand a 99.99% chance of spotting the bike, it must be travelling at 20% of the speed of the lorry i.e. 6mph? Does it also mean that it takes five times the clear distance i.e. 150m to almost guarantee spotting a bike travelling at 30mph?

As I said, maths is not my strong point. I tried putting some figures into an Excel spreadsheet and the answers that came out were rather worrying using my own formulae i.e. at 40mph a bike is totally invisible (in fact it had negative visibility ) If anyone out there manages to make anything of this, please let me know.

I do try and think when approaching junctions what the best place to be to get seen is. For example I'll stick the the middle of the road down residential streets so anyone coming from out from my right will hopefully see me instead of the row of parked cars. Perhaps that helps with getting a better angle so relative movement is greater, again improving the chance of being seen as suggested by the article.

Of course, I could just be lucky

As Scoobs says, you just gotta be careful. You don't even need to slow down (although thats often a good idea - saved me from going over the first guys bonnet), just make sure you've got an escape route. The way I got out of the second incident was probably more shocking for the car driver. I'd got the feeling she'd not seen me, but instead of slowing down I checked that the other side of the road was clear. So the first thing she knew about me being there was when I belted past her at full throttle on the wrong side of the road doing about 80

[BillyC]

Originally Posted by Flamin_Squirrel

I belted past her at full throttle on the wrong side of the road doing about 80

Cor! Those restricted bikes do go well don't they!

I've seen 110 on the speedo, and that IS restricted.

Over here it's the law that you should have your ligth on at all times when riding, and it does help, especially on those gray days. For the same reason it is impossible to turn the light off when the ignition is on.

Originally Posted by Nick762

Is it possible that under certain conditions, a bike is invisible?

Did you ever do that experiment in science lessons at school about a human's 'blind spot' in your vision?

Something like focussing just past an object as it moves away or towards you and at a particular point it will dissapear.

Considering the size a biker will appear to be when approaching a car down the road, it wouldn't surprise me at all if you didn't, at some point, hit their physical blind spot and literally dissapear.

Considering speed, reactions etc... by the time you reappear it's probably too late to avat a collision - in some cases anyway.

Originally Posted by mrbizzy

With so many potential hazards on the road youd be weaving around like a maniac! Seriously though, anything that helps car drivers spot you makes good sense - im up for working it into my riding style.

I think this will increase the number of times you'll get pulled over & breathalysed (sp ) though

move out to the centre of the road. to enable people to see you further on down, then move slightly to the left abit once they have made eye contact,

1 - this enables them to see you earlier. the movement also shows that you are there.

2 - in this position, you can pretty easily swerve to avoid them,
esp when someone has pulled out on you, they dont carry on with their manovre (allowing you to brake, then swerve behind them) they stop in your path allowing you very little leway - esp if there is oncoming traffic.

I remember that one on "Police, Camera, Action" back in the early 90's where a guy in a Fiat Panda who'd literally just been pulled over by the cops for something (can't remember what just now...) went straight out of a T-junction into a bikers path and knocked him clean off. The bike was doing over 80MPH at the time. The accident looked hideous but the commentator stated the biker made a full recovery.

Sometimes you wish they'd just ban cars. Then we wouldn't get people in Mercedes MLs driving at 45 in a 30 with no hands on the wheels, on a mobile phone while lighting a fag.