Tech Smart
Gary Anderson
Life and Death by GPS
Things you should know about navigation systems
Our recent experience navigating English streets, roads and highways in a 2017 CLS250D Shooting Brake, with assistance from the onboard GPS-based navigation system, was quite a learning experience.
On the one hand, without GPS guidance, we’re not sure we would have found our way out of and into the proper parking garage at Heathrow Airport at the beginning and end of our journey: Given the perpetual state of construction – entrances, exits and available roads change, literally, from day to day, often faster than the signage can keep up – navigating is difficult there. On that same route, our GPS instructions next routed us on an unexpected detour through a little village and back onto the main road to get us around a traffic jam caused by a tree-trimming crew on the main road.
On the other hand, one day when we complacently keyed our destination for a National Trust historic home without looking at a map of the area – or even knowing the name of any nearby landmarks – the farther we drove, the more concerned we became. The instructions took us from a good two-lane highway to a narrower two-lane road, then to a one-lane paved road with towering foliage on either side – and then on to a lane that consisted of two dirt-tire ruts cutting through a grassy field. Only after driving along this path for about a mile – praying that we didn’t encounter some piece of agricultural equipment coming the other way – finally and fortunately, we were directed through a gate and back on to the main road, discovering we were only about 100 yards from the back entrance to our destination. But by that time, we couldn’t have said with any accuracy where we were, from which direction we had come, or even which way was north.
Death by GPS
We’ve all read about worse situations: Drivers followed their GPS directions in isolated areas, only to wind up stranded for days off the main road, or even dead. In his forthcoming book Pinpoint: How GPS is Changing Technology, Culture, and Our Minds, author Greg Milner points out that dire outcomes have become so common that rangers in Death Valley National Park in California have a name for the phenomenon: “Death by GPS.”
This situation can arise when the GPS, calculating the most efficient route from point A to point B, doesn’t take into account the nature and condition of the roads; availability of fuel, food and other resources; relative safety of the area; and time of day, visibility or weather conditions. The consequence can be that the system’s recommended route becomes impassable; it may not even be possible to return to the starting point.
Milner also describes two cognitive problems. Recent neuroscience research has shown that as we move through space, our brain normally maintains a constantly updated map in two dimensions of our surroundings, based on where we’ve been and where we intend to go. This mental map orients us and helps us know how to get where we want to go – or back to where we’ve been.
Recent experiments have shown that the more we rely on specific external instructions to make our way – “turn left,” “turn right” – the less we know in the short run about where we are, and the less capable we are of replicating our route. Longer term, that mapping ability in the brain can actually atrophy.
In our efforts to find our way around Dorset, a historic region of England – with roads laid out in an agrarian era by people on horse or on foot – we had been relying, more than we should have, on the navigation system.
Simple fixes
By the end of the week, however, we had figured out some simple expedients that we recommend to anyone using an onboard, aftermarket or smartphone navigation system in an unfamiliar area.
First, before you use the system for guidance, check the settings. Only after we found ourselves on two worn dirt ruts between two pastures did we discover that the Mercedes-Benz navigation system in our CLS had been set to take “shortest route” rather than “quickest route.” The former is almost always a bad idea because it will intentionally take you, for example, off a bypass road that circles a city and route you through the city center, or as it did for us, direct you on a shortcut that some farmer had cut across his fields to avoid going around several properties on the main roads.
In addition, we discovered that the settings allowed us to avoid unpaved roads, but only if we specifically ticked that setting. Sure, there might be times when a route would include gravel roads, but most of the time, it is much wiser to stay on paved roads.
Second, before you launch off toward a destination based only on a street address or named point of interest, look at a physical map – yes, they are still available, though they are getting harder to find – or even an internet map on a large computer screen, and get fixed in your mind the general direction you’ll be traveling, the points where you’ll make a route change, and the relative distances of each leg of the route. Then, as you drive the route, keep track in your mind of where you are on your mental map.
Common sense
The GPS can be very useful to notify you of a turn ahead, show you a picture of a complicated intersection, or guide you through a complex maze of turns, such as into or around an airport, but it shouldn’t be allowed to substitute for your own decisions about how to get where you want to go.
GPS-based navigation systems, properly used, can be an effective tool, but poor use can be, literally, a matter of life or death.