The majority of cell phones available today have built-in GPS functionality. While many phones that are manufacturer-specific and those that are much simpler only have GPS available for e911 functionality, phones which run the Windows Mobile operating system are apt to have GPS functions available for the user. Along with the applications which came with the phone and those available for retail, it’s also possible to develop programs for these phones via Microsoft’s development tools.
Custom-tailored production scheduling software can also involve using custom cell phone applications to ensure shipping occurs correctly. When a shipment is delivered the driver would turn on the cell phone and start a specially-built program. This program uses GPS to find the driver’s position, connect to the internet and, back at the factory, automatically record where the driver is and what time he or she is there.
There are many other possible aspects to this kind of software. The cell phone could also be used as a tracking device. If the driver is given “waypoints” such as specific rest and break liocations, these could also be logged back at the factory as check-in locations. This ensures the driver is where he or she is supposed to be.
One point about GPS software, even GPS software that is custom-built, is that it can be … what’s the word … persnicketty. It’s not so much the software as it is the GPS system itself. The satelites are located around the equator. Inside a building the signals from the satelites can be quite weak and the further you get from the equator the weaker those signals become. It takes signals from 3 – 4 satelites for a GPS receiver to calculate correct latitudes and longitudes. Within a wood-framed house at 41 degrees north, this author has found that while 4 satelites are available within the south end of the house, only one satelite can be seen within the north end of the house.
When working with GPS it’s important to acknowledge the system’s limitations. The system is good, it works, and it can obviously be made to work with production scheduling software. It just requires a lot of patience.