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Case Study: Level Crossing

Case Study: Level Crossing

| On 17, Nov 2018

Darrell Mann

Humans can be pretty dumb sometimes. Everything the automotive industry does to make cars safer, we all compensate for by driving worse. There’s a similar phenomenon in the rail industry: the safer the level-crossing systems the rail industry puts in place, the dumber our behavior when using them becomes. The internet is full of people doing dumb things at level crossings. Sometimes getting away with the chances they take. Sometimes not being so lucky.

The railway industry – like their automotive counterparts seem to be caught in a horrible downward spiral: every time an incident hits the media, the more pressure the industry has put upon it to be seen to be making things ‘safer’; the more they do that, the dumber we all become. The obvious – but politically unacceptable – solution would be to make level crossings (and cars) less safe. Then we might all be encouraged to travel through life looking at where we’re going rather than playing Angry Birds 2 and checking out how many new BFFs we acquired on Facebook today.

Something else needs to be done. And, perhaps doubling the irony, the least likely fruitful direction of investigation would be asking the people why they sometimes do dumb things at dangerous places like level-crossings. The problem is this. When we’re thinking rationally – in a commuter interview panel session for example (the usual industry means of capturing the ‘voice of the customer’) – we’re using a completely different part of our brain to when we’re in the middle of making dumb decisions like crossing railway line after the barriers have come down. If we wanted to get meaningful input we’d quite literally have to interview people in the half second before they started jumping the barrier. Not totally impossible, but there are better ways to think about the problem and that is to get ourselves down to the limbic brain and the first principles of human behavior: our desire for Autonomy, Belonging and Competence for example.

Putting ourselves in a position where we can see the barrier-jumping problem from this limbic perspective is something that any of us can make a conscious decision to do now we know how simple the rules are. When we do this job, using the COBRA process and particularly the ‘B for But’ stage, we can construct a Perception Map based around a start question something like, ‘Ideally, people would always follow the instructions at level-crossing barriers, but…’ Then we can start putting ourselves in the position of a frustrated pedestrian stuck at the barrier, or a late-for-work driver. Figure 1 is a list of the ‘real’ main ‘yes, but’ statements such people might express were we to capture their (subconscious) thoughts at this critical moment:

Figure 1: ‘Real’ Reasons Why People Sometimes Do Dumb Things At Level Crossings

Then we can turn the perceptions into a Perception Map using the usual ‘leads to’ method of mapping the relationships between each statement. The results of doing this are reproduced in Figure 2. Unlike the generation of the initial perceptions, there would be some merit in asking a broader spectrum of people their opinion about the ‘leads to’ connections. The Figure 2 map has been drawn based on a consensus of four SI team members. If, when you look at the map, you think we’ve got anything wrong, we’d love to hear from you. In the meantime, check out the map on the next page.

The first thing to notice is the presence of two downward-spiral loops. This should immediately tell us there are at least two independent problems that will need to be addressed if we’re going to identify any (politically acceptable) solution ideas. The first of these loops – on the bottom left of the figure – is all about the non-linearity of time when we don’t have any feedback to tell us how much longer we’re going to have to wait, when we could have been doing something useful with our valuable time. On the face of it, this doesn’t seem like a massive problem to have to solve. One of the iconic (very likely apocryphal, of course) TRIZ stories involves a similar problem involving occupant impatience in elevators for high-rise buildings. When the first complaints started to appear, engineers spent lots of time trying to make the elevators go faster. Then, along comes the TRIZ expert and tells the designers to forget about faster elevators, just put mirrors on the inside of the elevator. Hey presto, problem solved: now we can be doing something ‘useful’ while we wait for our floor to arrive.

Figure 2: Perception Map Of Reasons People Sometimes Do Dumb Things At Level Crossings 

More recently, we’ve started to see the ‘feedback loop’ problem being solved by the addition of simple information screens. Figure 3 illustrates the sort of solution found in non-rail public-transport sectors in the UK:

Figure 3: Possible Single-Step Breakthrough Solution Strategy

This leaves us with the second loop from the Figure 2 Perception Map. This loop is all about the combination of a cruel optical illusion and the fact that the large majority of barrier-racing efforts do not result in any kind of injury – physical or to our pride. The loop indicates that these two things create a potentially very sinister downward spiral that tells us the more we get away with our poor decisions, the less likely we are to realise the magnitude of the optical illusion problem. Indeed, the more we get away with things, the greater the likelihood that the optical illusion becomes greater and greater… until the tragic day when… ker-splat.

This second problem has all the hallmarks of a rather stubborn contradiction problem with both tangible and intangible elements to it. I mapped it onto the Contradiction Matrix as reproduced in Figure 4:

Figure 4: Mapping The Safety-Versus-Optical-Illusion Conflict

It’s quite unusual for Principle 28, Mechanics Substitution to head up the list of suggested solution directions. The message that mechanical solutions should be replaced with ‘fields’ prompted a patent search for such solution strategies to the level-crossing problem. There are indeed several ‘field-based’ barrier solutions (laser, RFID, radar, etc) albeit the fields tend to be used as sensors rather than to solve the optical illusion problem at hand. Principle 28 as beginning to look like, if it was relevant at all, was very much a pointer to a long term future of autonomous vehicles and very accurate GPS location and thus a much more super-system oriented solution to the safety problem.

We were about to move on to the next Principle, when we remembered the more modern alternative interpretation, ‘Another Sense’. The problem at hand is all about an optical illusion issue, so why not think about introducing another sense into the story becomes the provocation. Sound probably being the most obvious connection. A patent search revealed nothing (other than one or two ‘ultrasound’ – again used as a presence detection sensor rather than directly solving the problem), but it did force us to recognize the existence of a currently untapped resource in the system. One that old Western movies featured a lot: how do the baddies work out the train is coming? Answer they put their ear to the line and listen. Why not amplify and/or maybe exaggerate that noise to emphasise the presence and speed of the arriving train? Why not – a bit more radical – use a combination of detection of someone or something ignoring the barrier and blast them with some directional sound (so we don’t pollute everyone else) to shock them out of their optical illusion?

Figure 5: Potential ‘Another Sense’ Train Approaching Resource?

At the very least, we know it would be easy enough to test the idea. And, if we think about it, this wouldn’t be the first time or place acoustic-shock has been used to trigger our limbic brain to halt an important fight/flight response…