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Scientific studies explain SMIDSY

Motorcycle crash road safety first aid SMIDSY scientific university

Riders might think drivers don’t care about hitting us, but there is actually scientific evidence that shows they really don’t see us.

Of course no driver wants to run into a motorcycle, bicycle or pedestrian. After all, it would cause extensive and expensive damage to their vehicle!

The problem is that comparatively small road users tend to exist in drivers’ blind spots and they need to be made aware of this so that they look twice.

There have been several scientific studies done into “Sorry Mate, I didn’t See You” (SMIDSY) crashes between cars.

The Alliance of British Drivers has produced the following excellent video which explains one of the scientific  principles of SMIDSY called saccadic masking.

Do a Google search for the term and you will find it is a “phenomenon in visual perception where the brain selectively blocks visual processing during eye movements in such a way that neither the motion of the eye (and subsequent motion blur of the image) nor the gap in visual perception is noticeable to the viewer”.

In other words, when a driver looks left and right at an intersection, there are blind spots in their vision that hide small objects such as pedestrians, cyclists and motorcycle and scooter riders.

To test it, go to the bathroom mirror and get fairly close. Now, look from one eye to another. You will not be able to see your eye move.

Yet someone else will see your eyes moving from side to side.

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A Texas Tech University psychologist has also found that people think smaller objects – such as riders – are further away than they appear and, conversely, that bigger objects are closer.

Researcher Pat DeLucia reached her scientific finding by testing people in computer simulations.

She studied participants who viewed two approaching objects simultaneously – one large and one small. The viewer had to nominate which would reach them first.

Her study, “Current Directions in Psychological Science”, indicates that an object’s size affects distance perception, causing drivers to miscalculate riders’ distance and speed.

“People generally picked that simpler heuristic: Larger is closer,” says DeLucia.

Motorcycles, pedestrians and cyclists are the smallest road users. Of those, motorcycles are the fastest accelerating, so we have double the perception problem.

Drivers think we are going to arrive much later than we actually do and think they have plenty of time to make a turn in front of us.

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The video above is targeted at drivers, not riders. And that is exactly what needs to happen to stop SMIDSY.

Our taxpayer dollars should be spent on educating drivers that SMIDSY, saccadic masking and perception problems really do exist and to always look twice.

The video not only suggests drivers look twice, but also train themselves to see better and avoid saccadic masking.

10 ways riders to avoid SMIDSY crashes

  1. Position on the road is important. You need to ride in the wheel track closer to the centre line so you are visible sooner to oncoming traffic or vehicles turning across your path. It also gives you a buffer from vehicles suddenly emerging from a parking bay.
  2. Weaving from one wheel track to the other also draws attention. It may look erratic and as though you have lost control, but it attracts much-needed driver attention.
  3. Never assume a driver has seen you.
  4. Assume they haven’t seen you and prepare an exit route in case they drive out in front of you or merge into your lane.
  5. Don’t ride in a vehicle’s blind spot.
  6. Give yourself a buffer  zone from other vehicles.
  7. Slow down and get ready to take evasive action if you see a vehicle at an intersection.
  8. Wait until you see the whites of their eyes before accelerating. And even then, prepare for them to make a sudden move.
  9. If so, it is best to think about changing course behind the car, rather than in front of it. The normal reaction is to weave away from the direction that the threat is coming. However, that leads you into the direction the threat is heading, so you may still collide.
  10. If you don’t see the whites of their eyes, then it might be time to give a polite toot on the horn to alert them.
  1. There is also inattentional blindness this is where a person can look right as something and not see it because it’s not what they are looking for; people have driven into trains and pulled out infront of trucks because although they saw them they didn’t register as existing.
    Still no mention of the masking power of the ridiculously thick A pillars
    I have lost sight of a truck due to the pillars in my car and even in the video the cyclist was entirely hidden.
    A pillars don’t need to be that thick to be strong it’s just cheaper to make them thick.

  2. No mention of adding additional daytime running lights to your bike? Having an additional light on either side of your bike at a lower level than the main headlight(s) is said to create a triangle of lights that greatly increase “attention-grabbingness”* of your bike to car drivers.

    (* it’s a word trust me)

  3. My perceptions of 44 years motorbike riding; There are car drivers who just don’t look. Those that don’t look long enough. Drivers who see the smaller image of a scooter/motorbike as being further away. Fog lights that run all the time here, I never hesitate to use twin Stebal horns. Serious evasive action (non-stop riding calculation of placement & where to escape) Fine tune & trust your instincts, NEVER their indicators, eye contact, or their commonsense 🙂

    1. If you need to sound your horn, you have already missed the chance to use your brakes…. even if it is your righht of way, it is no good affirming that right from a hospital bed – as the vulnerable party it is wise to defer to might.

  4. This is all good stuff. But unless I missed it there is a vitally important component not covered. Here’s the thing: drivers OFTEN DO SEE YOU, BUT as a motorbike YOU ARE NOT CONSIDERED A PERSONAL THREAT TO THEIR SAFETY surrounded as they are by their steel cage. Many is the time I have made direct eye contact with a driver who then pulled out in front of me anyway. Yes, they might misjudge my speed of approach, but – and I know this because I have done it to cyclists – because I am not a major physical threat they give it a go anyway. If you think about it, you will probably recall instances when you have done just this yourself. I am not shouting with the capital letters just drawing attention to the key point.

  5. I have 2 bikes. One looks similar to a police bike.

    Funny thing is, this mysterious Smidsy disease is instantly cured by the sight of the one that looks like a police bike.

  6. I know I’m only one person but in the 40 years I’ve been riding the number of times I have not been seen on my bike is about 4 or 5 times and all of those in the last eleven years. Three have been at night but the most memorable one was a little old lady who turned into the car park I was in. She ignored the give way signs, never looked left or right (intersection in car park) and went straight through. I had the impression that she had spotted her place to park and with tunnel vision got there as fast as possible. The important thing was I saw her and slowed accordingly and went behind her.

    The first picture above puzzles me. If you have to take evasive action why is the rider going towards the front of the vehicle? Should be aiming to go behind.

  7. Always always ride with lights on and in day time hours use high beam ,if some one flashes you there high beam you know they see you ……………

    1. High beam is proven to destroy depth perception in other road users – causing them to misjudge how close you are. This makes accidents more likely, not less. Please don’t use high beam in the daytime unless you want to donate your organs.

      1. I saw one of those daytime high beam riders about a week ago. Totally inconsiderate to oncoming riders/drivers.

  8. Being a founding-member of ‘The Self-Preservation Society’ I practice one trait consistently when riding..I make it MY JOB to make sure I am both visible & seen. That way I am removing the danger of letting someone else decide my fate.

    But, the comment above about riding with full-beam on all the time is not only illegal but also dangerous and inconsiderate.

  9. I agree with the posting, Weaving form one lane to another give the driver of the other vehicle that there is a motorcycle coming combined with High Viz clothing you cannot be missed or mispercepted.

  10. Al & Doc. Get the cookies for my experience. As a light off day rider. I don’t kid my self that any one sees me ever. Except the cops as I still ride with my 5kg dog in the safest (illegal) spot on my tank. Do know in Vic it’s legal to have ur dog safely on ur headlight. Cops advised me. Pollies r thick in general. Rich but thick.

  11. Out of curiosity, how fast do you have to go to completely bury your bike in a hatchback, and bend the car nearly in half?
    I must point out – I am not anti riders at all, and always move to the side to allow them to pass safely, but they do have a tendency to travel faster than necessary, and approach speed may be a factor in accidents even when a car driver does see them.
    I get annoyed with drivers cutting corners, but I have also seen riders, while not actually cutting the corner, leaning so far over the centre line that their head would end up in a different county if there was oncoming traffic.

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