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*** SCIENCE OF BEING SEEN *** The importance of lateral movement

*** SCIENCE OF BEING SEEN *** The importance of lateral movement “Where other drivers turn across the path of a motorcyclist, this can be because the motorcyclist…is not seen by the driver…This points to the need to improve driver awareness of motorcycles, as well as raising awareness among motorcyclists of this issue, which is a key factor in many collisions. By running headlights during the daytime and wearing high visibility clothing, motorcyclists can help to improve their visibility to drivers.”

That’s from Transport for London’s ‘Motorcycle Safety Action Plan’ published back in 2016. I don’t know if there’s been an update since, but essentially it ignores one very big problem behind the ‘Sorry Mate I Didn’t See You’ SMIDSY collision.


The motorcyclist also has to be aware that they have to position TO BE SEEN. When plans like this ignore this issue, it’s hardly surprising that so many riders still seem completely oblivious to the problem – OUT OF SIGHT, OUT OF MIND.

In researching the Science Of Being Seen #SOBS, I found that there were actually THREE causes of these crashes.

LOOKED BUT FAILED TO SEE: These are the visual perception failures where a bike that is capable of being seen isn’t spotted. These make up around 1 in 3 of all junction collisions, and for a variety of reasons to do with the way the eye ‘sees’ the world and the brain processes the visual feed, these drivers simply didn’t pick out the presence of a motorcycle even though it was there to be seen. These ‘Looked But Failed To See’ crashes are so common they are actually referred to as LBFTS incidents in the research literature.

Causes include ‘saccadic masking’, which happens when our vision shuts down as we turn our head, a narrow field of clear vision which leaves much of our ‘worldview’ dependent on peripheral vision, and ‘motion camouflage’ where the bike simply ‘grows’ against the background and the driver’s brain fails to detect it.

I have a very good clip of a Spitfire simply ‘appearing out of nowhere’ as it flies directly towards the camera. It’s visible if you look in the right place, but with our attention focused on the presenter, it falls outside our narrow cone of clear vision and in peripheral vision, and is effectively invisible. It’s only when it’s scarily close that it simply ‘pops out’ at the viewer.

And I think we’d all agree that a Spitfire is rather bigger than a motorcycle!

The problem is that lack of lateral movement to attract our attention, and there’s a very specific form of motion camouflage that happens when two moving vehicles are on a collision course. This problem has a name – it’s known as the ‘Constant Bearing, Decreasing Range’ issue. It’s a term used in navigation and flying which means that some object, usually another ship viewed from the deck or bridge of one’s own ship or another aircraft viewed from the cockpit, is getting closer but staying at the same angle – or maintaining the same absolute bearing.

If they both continue on the same course at the same speed, they WILL collide. And it CAN happen on the roads. Just ask yourself where; for example, when you’re approaching a roundabout and another vehicle is on an intersecting course and will arrive at the same time, or when approaching a cross-roads and another vehicle is approaching head-on. Since neither vehicle will appear to move relative to the background, it can be difficult for either driver / rider to perceive the other, even when in clear view. I’ll be coming back to this in a moment.

LOOKED, SAW AND MISJUDGED: And then there is a second type of driver perception error where the driver actually sees the bike, but thanks to the tall and narrow shape of a motorcycle, simply misjudges speed and distance and therefore miscalculates the all-important ‘time to collision’. Once again, it’s a well-known phenomenon in the research and accounts for a further 1 in 3 of junction collisions, usually on faster roads. These are ‘looked, saw and misjudged’ errors.

From the point of view of the rider, the result is that the driver begins a dangerous manoeuvre. Unfortunately, the driver often recognises for themselves half-way through that it’s not going to end well. The rider will often see this change-of-mind when a driver starts to turn across the bike’s path then stops again, frequently ending up stranded across the road ahead of the bike.

This happened in front of me years ago when I was couriering. With a car coming the other way, I had no ‘out’ to the right of the emerging car but had just enough room to turn behind it and shoot obliquely between the gate posts from which the vehicle had just emerged, braking safely to a halt on an immaculate grassy lawn.

The ‘looked but failed to see’ and ‘looked, saw and misjudged’ errors are the classic ‘driver fails’. And it’s always been assumed that advice to use improved scanning techniques would reduce the frequency of these errors. But speaking plainly, the crash stats over the last fifty years of ‘Think Bike’ campaigns fails to turn up any significant change to the frequency of car – bike collisions. And that’s because the human eye and brain were never designed to work at the speed of traffic. The crashes happen because the weaknesses are effectively built-in.

LOOKED BUT COULD NOT SEE: But there’s a third category of error. In around one in five collisions, the rider simply wasn’t where the driver was able to see the bike when the driver looked. The driver ‘looked but COULD NOT SEE’ the bike because it was hidden.

And it’s easier for a bike to go missing than you may realise.

Just watch the video.

Watched it? That was an object the thickness of a PEN blocking our view of the approaching bike.

Now, remember the Constant Bearing issue? Think about what’s happening here. The bike’s not only not moving relative to the background, the fact that it’s on a constant bearing means it’s not moving relative to the vision-blocking pen. And it’s scary how close the bike got before it moved out to where you could see it.

The pen is a Vision Blocker. Think about how many objects there are around us that block lines-of-sight – post boxes, telegraph poles and trees, moving and parked cars, hedges and walls, people walking along the pavement…

…even another motorcycle on a group ride!

Now, I want you to watch the video again. This works best full screen on a PC monitor if you stand about five paces away from the screen. This time stretch your arm out, then hold your hand up vertically with the palm facing away from you, so that you’re looking at the back of your hand. Cover up the policeman and his pen. When do you see the bike now?

Now go sit in your car’s driving set and take a look at the A pillars supporting the front windscreen. If you look at the width of the pillar nearest you, you’ll find it’s about the width of your hand, and it’s about the same distance from your eyes as your hand was when you stretched your arm out.

If you’re still not ‘getting it’, get a friend to walk towards your car whilst trying to hide in the blind spot – they’ll know when they’re in it because they won’t be able to see YOUR eyes. It’s scary just how close they’ll get before you spot them. And a bike’s not much wider than a person.

So now… combine the Constant Bearing problem with the blind spots created by the car itself.

As you approach a vehicle, check where the driver’s head is relative to your line of approach. If their eyes are behind one of the pillars (and the B pillar supporting the doors and the C pillar behind the passenger doors are just as big a problem when approaching from the side or behind), then you’re NOT VISIBLE. You CANNOT BE SEEN.

And we can’t rely on drivers predicting that there MIGHT be a bike they can’t see.

So ask yourself: “how can I bring the driver’s eyes into MY own line-of-sight?”

The answers should be fairly obvious. To ‘break’ motion camouflage and the Constant Bearing problem, all we need to do is change position and speed and thus create some LATERAL movement – hopefully the driver will now see us though a wise rider would still be prepared to take evasive action.

And specifically, we want to identify, then move out from behind, any ‘Vision Blocker’ in order to bring our bike into the driver’s own line-of-sight. That way we ‘uncloak’ our bike, and at least give the driver a CHANCE of seeing us.

Sadly, reading the comments on the FB post where I spotted this video, it’s depressing how many simply missed the point.

There were the usual bunch of “car drivers don’t look properly” or “aren’t paying attention” theorists, though a minor logic check would tell them that if they weren’t ‘paying attention’ they’d be bouncing off everything around them and not just bikes.

Then there were the “car drivers are distracted by their phones” comments. Certainly, you’re at far higher risk of a collision if you are a mobile phone fiddler when driving, but relatively few police investigations into crashes in the UK suggest that the collision can be pinned on mobile phone use as a primary cause. That’s all covered in SOBS.

But my ‘favourite’ comment was probably:

“This just shows that we need to make bikes more visible.”

If you’re in a position where you CAN’T ACTUALLY BE SEEN, how on earth does the writer think that ‘making a bike more visible’ is going to work?

In terms of sage advice, it’s right up there with:

“Drivers, check your blind spots.”

How exactly? They are called blind spots for a reason.

If you want to find out more about the problems of being seen on two wheels, why not sign up for the next presentation of ‘Science Of Being Seen’, on Wednesday evening?

=================================== APRIL’S LIVE EVENT – ‘SOBS – the full presentation’ Science Of Being Seen is a 45 minute talk covering human visual perception and motorcycle conspicuity, and explains why conventional hi-vis clothing and day-riding lights have proven less than successful at preventing junction collisions. Discover how to use Survival Skills ‘proactive measures’ in your own riding. WEDNESDAY 6 APRIL 2022 AT 20:00 Tickets cost £5.

The original video was shown here:

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