The curse of the Matrix

No, not the one Neo dealt with.

I’m talking about motorway matrix signs.

These matrix signs are those digital boards at the side of the motorway that supposedly display useful traffic information. The
idea is to aid traffic flow and reduce congestion.

Except they don’t.

Not used in the way they currently are anyway, particularly on the M6 between Stoke and the Manchester area – but I’m certain the
case is true in many other areas.

Useless matrix sign
Useless matrix sign

The idea is that traffic flow is monitored and when congestion starts to occur further on ahead, matrix signs suggest a reduced speed before the affected area. In theory, approaching traffic will slow down and by the time they reach the troubled area, the congestion ahead will be eased.

One problem is down to the way it is managed. There is often a delay before the message is displayed, by which time the congestion has already eased – so traffic at one point in the flow slows down unnecessarily.

Which can then cause congestion behind it.

Or there is no matrix sign located at a suitable point before the congestion; so the warning appears too late, when the
congestion has already been reached; or even too early: so drivers become frustrated at the reduced speed and ignore it anyway.

There’s also the lack of understanding of these signs by most road users and the somewhat different responses they can provoke:

Congestion ahead? Well… I’ll slow down when I get to it, not before it!


Congestion ahead? Well – I’d better slam the brakes on immediately and slow down!

Thus, when a “Congestion ahead – 40mph” message appears on a busy but flowing motorway, with drivers in the left hand lane typically
doing between 60 and 70mph, drivers in the middle lane doing between 70 and 75mph, and, let’s face it, drivers in the right hand
lane doing somewhere between 75 and 90mph – chaos ensures.

Rule following driver A in the middle lane, passing a lorry, travelling previously at 70mph, slams on his brakes to slow down to
40mph quickly.

Mr I’m-in-a-rush Driver B in the outside lane sees brake lights in the middle lane but scoffs at the warning and sees the right
hand lane ahead is clear, so increases his 80mph speed to overtake the ‘fools’ in the middle lane.

Average Joe Driver C in the middle lane, who is behind Driver A, panics at the brake lights, and not having left enough space in
front, decides his only option is to move into the fast lane – straight into the path of the accelerating Driver B.

Not good.

Obviously this is a rather extreme representation of what can happen, but I have seen a similar situation develop, many, many
times. Drivers panic and slow down abruptly, whilst others choose to ignore it – they don’t want to be told by computers to slow down because of something ahead that they can’t even see – they will make the decision using their own brains thank you very much!

And there’s those drivers that have experienced the early/late/outdated matrix warnings as I’ve outlined above previously and take the message with a pinch of salt.

I.e. ignore them.

So they don’t work. And in the extreme cases as highlighted above, can be dangerous.

As my esteemed ex-colleague Dave (AKA “MR GRUMP“) would say, matrix signs are “self-prophesying”.

Congestion 40mph“?

There is now!!

Admittedly, they can be useful.

Messages that display that a junction or road ahead is closed is useful and can allow you to plan ahead.

Unfortunately they still seem to distract the slower-witted drivers from the road as they struggle to read them, momentarily
forgetting that they are on a motorway, and drift from their lanes or fail to notice the vehicle in front of them slowing down.

For many, they are a dangerous distraction.

Especially when the message is obscure, irrelevant, or downright stupid – which is often the case.

Take some examples.

Don’t litter”

Ok. I won’t. But don’t put this on roadside sign where people are passing at 70mph. It’s distracting, and pointless, as people generally aren’t littering whilst driving down a motorway. And those that do are hardly likely to respond to it. There’s another variant I’ve seen on this: “Bin your litter: Other people do“.

Sheesh – way to put me on a guilt trip!

How about:

Wear your seat belt

I’m sure I learnt that when I was doing my driving test. Actually, I learnt it as a small child. I don’t need a a matrix sign to tell me that, thank you.

Firefighter strike drive with extra care

Oh ok. When they’re back off strike, I’ll drive like an idiot.

Scottish airports check with airline for flight details

Erm. Ok. I will. Thanks.

Unfortunately, motorway matrix warning signs are another case of technology being used for the sake of it, rather than solving a
problem. In this case, they actually create them.

Although it’s not always the advanced technology to blame for signage stupidity, as the following example shows…

Useless sign
Useless sign

Drive safe, people.

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