INSTRUCTOR: Bob Gummersall
This presentation included some very lifelike demos of GPS systems which are available in today's market.
Why GPS? The bottom line on this one is essentially safety. What RVer hasn't discovered the sense of insecurity that attends finding yourself in unfamiliar circumstances. This might be a wrong turn down a street with unknown options for turning around, or just plain being lost.
The benefit of GPS is that it can tell you precisely where you are. It provides four elements of information: Lattitude, longitude, altitude and velocity. The information comes from 24 satellites in stationary orbit around the equator, and which provide signals for "triangulation" capable of permitting a GPS unit to provide you with information about your location within 100 meters. Actually the system is capable of providing information which is accurate to a few inches -- but the military is reluctant to put this type of information into the public domain. As a consequence the information is purposely degraded for non-military uses so that it only provides an accurate location within 100 meters.
There are two general types of GPS units made for RVs. One is a fully dedicated and purposefully "rugged" system which reads not only the GPS data, but also the vehicles speedometer; and based on an internal gyro is capable of detecting small course adjustements as well. These units can provide location information which can actually tell not only which highway you're on -- but which lane you're in. These units come with a set of 9 CD disks with highway and street map/data. One disk includes all intercity travel within the U.S.; and the other 8 provide city street information for various regions of the country.
A demonstration of the Alpine system showed that it is capable of providing "voice" instructions. As you're driving, "Nancy Navigator" announces the distance to the next turn -- and can even tell you which lane to be in to get to the appropriate off ramp. The system works much like existing mapping software. You key in where you want to go, and it charts the optimum course. If you deviate from that course, for instance in the event of a traffic jam or a highway detour, it tells you you're off course but immediately recalculates a new optimal route from your actual location to your destination.
The Alpine system was recommended because of its screen brilliance and clarity, and because of the "RV friendly" software. The installed cost is approximately $2400.
The other option is a laptop based system, which requires a PC with a minimum of 200 Mhz speed, 32 megs of RAM, an availble 1 Gig of hard disk space, and an active matrix screen. The recommended system is TravRoute, with Copilot software. The cost is under $300. Other systems are made by DeLorme and Etak (phonetic).
The PC based systems do not offer the location-refining tools of the internal gyro or speedometer inputs, and thus remain capable of accuracy only within 100 meters. This precludes it from knowing which "lane you're in"; and where two roadways are in close parallel, it can mis-indentify which road you're on. Nevertheless, it offers many of the same advantges as the more rugged and accurate dedicated Alpine system. It also has voice recognition, which lets you "talk to" it, asking certain questions such as "where am I", etc.
It appears there may be some interesting issues relating to Y2K on older GPS machines. Some may not accurately read the "time" which GPS satellites provide, thus rendering them inoperative. This is something that should be investigated by anyone considering adding a GPS unit to their RV.