I love my GPS

 

In ages past, people getting ready for a long trip would visit their local AAA office to get a customized 'Trip-Tik'.  These were ring-bound 5"-by-8" strip maps each showing 50 to 300 miles of major travel roads.  AAA travel consultants would select the proper set of strip maps for the journey you had in mind and stripe them with highlighter pens to show the recommended route.  The back of each sheet listed recommended hotels, motels, restaurants, and service stations related to the route on the front side, each with its AAA-rating.  It was a complete, coherent collection of all the information you would need for that trip segment.  Together with its accompanying maps, it was everything you needed to know from leaving home to getting back home again.  Pretty neat, but labor-intensive, and when your plans changed mid-trip, useless, unless you could find a nearby AAA office to give you an update.

Automation has come to the rescue, thanks to a cluster of 69 satellites being used by three different positioning systems.  31 of them are what enable the GPS in your car.  As long as your GPS can 'hear' at least three of them, the built-in software can tell you where you are within about 50 feet anywhere on the surface of the planet.

We got our first GPS in 2009 in preparation for a road trip into the American Southwest.  We used it for a few weeks to get used to it before we left on vacation, then used it in our rental car when we got there.

Our first stop was at Canyon de Chelly (shay-ye) in Arizona.  The canyon has a 'v' shape with the two legs of the canyon extending generally east from the town of Chinle, AZ.  There are 'rim roads' along the south rim and the north rim.  On our first half-day there, we explored the south rim road.  The next day was spent taking guided tours into the canyons.  On our last day, we drove out along the north rim road to catch any sights we might otherwise have missed.  When we were satisfied that we had seen everything there was to see, I programmed the GPS for the next leg of our trip: to Mesa Verde National Park in Colorado with an en route pass by Shiprock, an ancient volcanic basalt core whose cone has eroded away over the eons, and which became a sort of 'mile marker' for pioneer wagon trains as they headed for California.  The GPS ordered me to turn right (east) out of the parking lot.

"No," I thought, "that's not right.  I have to go west into Chinle to pick up US-191 north."  My second thought was that this was a vacation and that I should go where the GPS pointed.  We turned east through rough wilderness via BIA-64 and BIA-12 and BIA-13 and BIA-33.  It was some time before I realized that these were Bureau of Indian Affairs roads, and the GPS was taking us directly through the Navajo (I presume) Reservation.  At one point, we were zig-zagging our way up the side of a mountain when we reached the high point and could see, straight ahead 30 miles away across the plains, Shiprock standing there like an obsidian ax blade sticking up out of the desert.  The GPS had given us a magnificent view as our reward for having faith in its ability.

You know how a GPS picks a route, don't you?  It has a vast encyclopedia of roads and facts about those roads.  It knows that from here to there, the speed limit is v and the distance is s, so the time to get from point A to point B is t.  It picks your route by adding up all the times from each possible route and selecting the smallest of those.

There are downsides to placing too much faith in a GPS, however.  Sometimes its advice is just plain wrong.  Usually this happens when you're in the vicinity of a city or metropolitan area.  The GPS may give you directions that seem to take forever!  The reason for this is simple, so simple that I'm amazed GPS-makers haven't added the SMOP (Simple Matter Of Programming) to their software that would correct it.  The mis-routing happens because the GPS doesn't allow for the time your speed will be zero because you're waiting at a red light.  The simple 'fix' is to charge 25 or 35 or 45 seconds to the route-time for every traffic light along the way.  You won't get stopped at every one of them, (unless you're on State Street in Erie PA) but when you do get stopped, it will be for several minutes.  Charging the route-time this way operates to make certain routes poor options for through traffic, and the normal GPS software will usually, then, de-select such routes even if they are more direct.

For road trips, however, most moderns have given up using AAA Trip-Tiks, and now rely exclusively on their GPSs, whether built-in or added-on.  Don't leave home without it!