I try not to speak much about my wife in my blogs, as she doesn't normally like it.  However, this one was kind of funny...

I was doing some research on "dead reckoning" for this blog and she thought I was looking up a movie review.  I laughed at it (as she doesn't always understand technology), only to find out that there was actually a Humphrey Bogart movie with the same name....so, I guess the joke is on me.

Ok, now on to the main purpose of this blog....should the GPS solution that you deploy use Dead Reckoning to increase its effectiveness?  For many customers, the answer is an astounding "yes", as it provides much more accurate results than what is offered by other technologies....and it is not always those deploying the most expensive GPS equipment who will benefit!

What is Dead Reckoning?

For most of us, we have come to fully understand what GPS does.  Whether it is used to tell us where the next bus is on our smartphone app, what turn to take to get to an appointment or where our airplane is in the sky, we use GPS to provide locations multiple times every day.  For many applications (such as Google Maps on your phone), the GPS co-ordinates from your phone are plenty accurate.  However, many applications are now starting to use more advanced GPS engines to provide both a much more accurate "fix" and a better amount of GPS data.  But, a key question arises....what do you do when you are not able to see the sky?  Try using it when you are in an underground parking garage...While there are other triangulation technologies that can help, your accuracy will be greatly diminished.

Now, what do you do when GPS is not available and you must know the accurate location of a vehicle/worker?  Such is the case for a first responder vehicle.  In many cities, there are a lot of "dead spots" in the GPS signals (either due to "urban canyons", tunnels, water or large amounts of underground facilities).  This is where Dead Reckoning (DR) solutions come in.  By using a number of sensors on-board, the system is able to begin with the last known GPS location as a starting point.  With that, it is able to determine the current position by looking at variables such as the position of the steering wheel, the diameter of the wheel (as well as the number of tire rotations) and the amount of braking.  With this information, the system is able to provide an accurate current location.

In addition to uses in automobiles, DR technology is used extensively in air and sea travel.  Although modern solutions exist for accurately tracking vehicles/vessels used in both of these methods of transit, most flight/nautical engineers are still quite well versed on how to enhance these solutions (or use them if GPS is not available) to accurately plot their current position.

So, does your solution need Dead Reckoning?

Well, it comes down to what level of accuracy you can live with and whether getting this updated (and more accurate) information is worth the extra cost (for equipment and in some cases, installation/setup). Here are my thoughts on a few scenarios...

•   If you are currently using the GPS from a handset for tracking on the person, the cost of a DR solution may not be easy to justify.

•   If you are currently using a lower to mid-tier cellular modem (to provide both GPS co-ordinates as well as the network to send back the data), a DR solution may be a good fit for you.  While the DR solution may be a significant extra cost (when compared to the current solution), it does provide an incredible extra layer of location accuracy in many situations.  When these solutions are being used as part of a Work Alone monitoring solution, it may make the difference in preventing a tragedy.

•   Finally, if you are using a rugged modem, the answer is likely a resounding yes.  Quite simply, if your application requires the uptime/reliability that is offered by a more advanced solution, it is quite likely that you will see a ton of value from the increased accuracy / availability offered by a DR solution.

The Bottom Line

It is understandable that companies are trying to watch costs wherever possible and deploying GPS solutions are often done with saving money in mind.  However, depending on the environment/locations where your workers are deployed (as well as the risks if you are not able to accurately locate them), a DR solution is likely not an expense that is worth skipping.  It can often be the difference between locating someone and them being stranded.  With an increased focus on worker safety (as well as many states/provinces enforcing work alone legislation), a DR solution may be the best insurance policy that you can buy.