Why? Continue reading after the break to find out!

Rationale:

In the primer I explained that we need to think of the MGRS coordinate system as a square region based on the precision given.

Let’s say a coordinate comes in with 1m precision, 1367507896. To report this, we need to convert it to 10m precision. Here’s how it looks if we round vs. truncate:

• Rounded: 13680790
• Truncated: 13670789

Note that our objective originally reported isn’t contained by the rounded search area coordinates. This isn’t a very compelling argument, since the objective isn’t much outside the search area. Let’s start looking at more compelling arguments.

The incoming coordinate is now 13670789. The reporter says he isn’t sure of the 10m precision, so the commander orders a search of the 100m area. Rounded vs Truncated:

• Rounded: 137079
• Truncated: 136078

Now we see how much rounding can hurt a search for an objective. But you might not still be convinced that we should be truncating vs. rounding. So I’ll throw my ace in the hole out there to you.

We receive a report that our objective is somewhere in the vicinity of 136078, but our reporter doesn’t have an accurate GPS signal. Our commander sends out his forces to scour the entire 1 km grid square. Rounded vs. Truncated:

• Rounded: 1408
• Truncated: 1307

So now we have an angry unit and commander cause they just spent hours wasting their search efforts in the entire wrong spot.

I welcome all comments/feedback!

Ben (benjamin.post@primordial.com)

Direction: Read and understand this document and if needed, direct questions to Benjamin Post. (benjamin.post@primordial.com)

Motivation: Given Primordial’s product line and customer base, it is paramount that our employees understand how our customers reference locations in throughout the world. MGRS is the de facto standard for reporting coordinates in the United States military, and has also been adopted by NATO.

Background

MGRS is the geocoordinate standard for all NATO militaries. Barring naming conventions, the actual grid between 80˚ south and 84˚ north is identical to Universal Transverse Mercator (UTM). So, if you are familiar with UTM coordinates, then really you just need to learn the language of MGRS to interpret locations. The grid for the polar regions is based on the Universal Polar Stereographic system, but with the low probability of ongoing military operations in these regions we will ignore these regions for now. Modern MGRS is based on the WGS84 geodetic datum.

MGRS Coordinates

Now that we are familiar with the background of the MGRS, let’s dive into breaking apart an actual MGRS Coordinate.

15T VK 86049 79921 – Places us at the cursor location seen below, which FYI is right outside our office in the parking lot. (Notice the lower right corner of the pic?)

15T represents the Grid Zone designation, which represents an area that is approximately 6˚ wide and 8˚ tall relative to Latitude and Longitude. (Pretty big.)

VK represents the 100,000 meter square identifier. Pretty simple, it covers a 100,000 meter square. It is important to note that these regions are not perfectly square, nor are they always 100,000 meter squares.

86049 is the Easting value within VK. This is the horizontal position within VK, meaning that we are 86049 meters east from the western edge of VK.

79921 is the Northing value within VK. This is the vertical position within VK, meaning that we are 79921 meters north from the southern edge of VK.

Here’s how we read the MGRS Coordinate:

1. Locate the Grid Zone designator. (Hint: 1 is the International Date Line heading East and ends with 60 back at the International Date Line, and letters go up from 80˚S starting with C.)
2. Locate the 100,000 meter square designator. This uses the AA format, meaning that the indentifiers will cycle through letters of the alphabet. (O and I are omitted, consider why for a moment.) This is far too difficult to explain, so here is a picture to help. Notice that A, H, J, R, S, and Z are used for oddball identifiers along the east and west edges…Squint harder. [Update: Thanks to Mikael Rittri, who made the MGRS grid in SpatialAce of Carmenta, with a background map from Natural Earth by  Tom Patterson, US National Park Service.]
3. Now we get to the Easting and Northing. In the military we read this as “left to right, then up.” I have also heard to it referred to as “in the house and up the stairs.” Either way, here’s how it is done using our string from before. Did you forget it already? 15T VK 86049 79921
   1. 86049 79921 – 86,79 represent the gridlines we want to find. So we locate the intersection of these two lines. (Remember-left to right, then up.) Going horizontally we locate 86, then following that gridline up vertically we locate 79.
   2. 86049 79921 – Now here we want to go 049 meters horizontally, followed by 921 meters vertically.
4. Congrats…

MGRS Precision

Not much can be done about the Grid Zone designation and very little will affect the 100,000 meter square identifier, but the number of digits used in the easting and northing will vastly affect precision. Each digit represents a magnifier of 10 in determining the precision of a given coordinate. Let’s break it down, shall we?

Easting and Northing can come in 2, 4, 6, 8, and 10 digit strings, and more digits equal greater precision. Here it is best to picture the coordinate as providing a square area versus an actual point.

2 digits represent a 10km X 10km square. While it is highly unlikely that we will ever see this in use, we must be aware that it is possible to report this way.

4 digits represent a 1km X 1km square. This is significant in that it actually identifies a grid square. If we are given the following string 15T VK 8679 as coordinates for an enemy compound, then we must assume that the compound is located anywhere within the grid square designated by 86,79. While this may be acceptable for easily identifiable features, i.e. mountains, lakes, villages, etc. It is inadequate for actual point locations.

6 digits represent a 100m X 100m square. While this is not ideal if you absolutely want to be located, or to locate a specific person of interest, it is good if you are in a pinch or cannot accurately determine your exact location. If we are given a coordinate string of 15T VK 860799, then the location of interest is located in the following area.

8 digits represent a 10m X 10m square. This is the standard for reporting point locations in the military, so get used to seeing this. Here’s what it looks like if we are given the following string. 15T VK 8605 7992 – Notice rounding occurred in the easting value. If you can’t find what you are looking for in this location…God help you.

10 digit values represent 1m X 1m, which is about as close to a point as you can get. This is not widely used in the military due to inaccuracies in GPS reporting devices. Maybe they should upgrade to farm grade GPS receivers, those things are crazy accurate. No need for a picture as this is the point of the cursor.

The National Geospatial Agency provides a compelling argument as to why military coordinates should be limited to 6 and 8 digit easting and northings. Here is what they have to say from their Military Map Reading 201 guide.

“An often-confusing point is that most NIMA 1:50,000 scale maps are made to an accuracy of 50m at the 90% confidence interval. This means that 90% of all well-defined points on a map will fall within a 50 meter radius of their actual position on the earth’s surface. The confusion comes in when soldiers try to use a map to get a 10-digit grid coordinate, which equates to a 1 meter precision. A 1:50,000 scale map is only accurate to 50m 90% of the time so a 6 digit (100m precision) or an 8 digit (10m precision) are more appropriate.”

Conclusion

Hopefully this primer has you ready to dive into the world of MGRS coordinates and military map reading. It might seem a little intimidating at first, but after a little studying of the basics, you will find that it makes sense. I hope to expand on this primer by offering a class or perhaps authoring another reading on how to use a military protractor to determine locations on military maps and other land navigation practices.

References:

http://en.wikipedia.org/wiki/Military_grid_reference_system

National Geospatial Agency’s Military Map Reading 201

Of course the legendary Army Land Navigation Field Manual (FM 3-25.26)

My Brain…Access is limited, but space is available!

- Benjamin Post

Primordial’s goals in attending the FTX were to learn more about the workflow of convoy operations and to demonstrate our integration of Ground Guidance with the Movement Tracking System (MTS).

A little history about Manassas and Bull Run.

Timeline

11 May 08

Normally I wouldn’t really make a big deal about a travel day, except this wasn’t a normal travel experience.

No flyer enjoys the following phrase:

“Folks, this is the captain speaking…We seem to have a problem…”

We were about halfway over Wisconsin, ended up turning around and heading back to Minneapolis and sat in the terminal for over two hours waiting for our plane’s de-icing equipment to be fixed. By the time we finally arrived to our hotel rooms it was roughly 3 am EST.

Felt like being in the Army again…Except this time I wasn’t stranded on the tarmac of Kuwait International airport waiting on repairs to our plane home…

for 8 hours…

in the middle of the night…good times.

12 May 08

Monday was a typical meet and greet day. We met with Mike Haney, the Project Manager at Fort Eustis for the MTS. Mike gave us a quick tour of the relatively Spartan facilities available to us, which consisted of a lot of concrete, some chairs and desks.

We also met with some of the TBOLC students, who were part of the advance party and were setting up the facility. One of their major tasks was to set up a sandtable of the area, which had to be one of the most tedious tasks we have ever witnessed. Which led to Great Idea #1:

A Sandtable feature for Ground Guidance:

• Leverages technology to quickly construct/maintain the battlefield and disseminate that information.
• 3D Mode to provide virtual reconnaissance of the battlefield prior to actual recon.
• Users are able to plot routes, cordons, threats within that battlefield.
• Route flythrough to assist soldiers comprehension of the route.
• i.e. Difficult maneuver areas, Potential ambush/chokepoint locations along the route.

Work interrupted by some heinous chemical warfare.

Primordial did give a quick class to the students on some of the changes made to the system since we last saw them. Check out Kyle and Robert in action.

13 May 08

Tuesday had more set up involved, so it was a relatively light day for us. The rest of the Primordial fellas were introduced to the military concepts of “Hurry up and wait” and shamming. But the day wasn’t a total wash. Right around the time we were getting ready to head out for the night, we were approached by one of the students who wanted to use Ground Guidance to figure out distances for the legs of his route…which lead to Great Idea #2:

A Distance feature for Ground Guidance:

• Provide distance calculations between two points.
• Distance from current position along a route to the next checkpoint.
• “As the crow flies” distance between two points.

14 May 08

Wednesday was the first day of heading out onto the Situational Training Exercise (STX) lanes, time to see what this show is all about. Kyle and Robert went out with the convoy while I rode out to Camp Cooke with Mike to set up the RFI scanner.

The route was about 17 kilometers, and knowing that there would be some issues and complications along the way…it took them a little longer than expected to reach our destination! I guess this kinda happens when you take a few wrong turns and break the law.

Meanwhile, Mike and I keep busy while waiting for the convoy to arrive.

In the afternoon, Robert and I rode with the convoy while Kyle did boring office work. Our STX run seemed to go much smoother, as the students learned from the morning mistakes and performed corrections. Of course it helps when you have a prior SSG providing navigation.

Since we were under the impression that we shouldn’t interfere too much with the soldier’s preparation and execution of their missions, we didn’t bring an actual working version of Ground Guidance with us on the convoys. We had GG installed on the MTS machines, but since we were unable to read the MTS GPS signal it became a digital strip map.

After the day’s convoy ops, Mike told us to go nuts and help out an anyway we could. So we planned to bring our own laptops and GPS devices along for the next day’s operations to see how it would go.

Eureka! Kyle discovers that MTS provides a local GPS position signal every 15 seconds.

15 May 08

Thursday we rolled in early to get our gear setup with the morning convoy’s route. Proud to say that GG passed the test with flying colors, even assisted in navigating through a four way intersection that Robert described as a “Chicken Foot.” As soon as the lead truck started to turn on the wrong road, the soldier quickly recognized it was the wrong way and was able to correct the vehicle before leading the convoy down the wrong road.

!Warning: Author’s unabashed love of GG expressed in Text!

We found that several of the students really grasp the capabilities that GG offers a decision maker. Route planning by hand is truly time-consuming, especially in performing terrain analysis and calculating route distances. (Tick marks on your paper for curved routes = fail.)

While I do not consider myself to be a pro land navigator, as a former NCO in the Army I have experienced plenty of land navigation courses on a variety of terrain, and I find that GG routes are consistent with what I would choose. Additionally, I am amazed that these routes are generated within a matter of seconds compared to minutes it would take to hand plan it. Think about that for a second…a potential life-saving route generated for you in seconds, compared to minutes. Pretty powerful stuff when a situation quickly turns south.

Just checking…Yup, Apaches are still cool.

16 May 08

Friday had two convoys rolling out in the morning and those would be the last STXs for the FTX. Robert and I split up and saddled up with the convoy lead vehicles. I would love to say that GG assisted in navigation for my convoy, but there were 2 factors in why it did not:

1. I failed in my PCC/PCIs – Meaning, I had dead batteries in my GPS and didn’t check it prior to leaving. Quick check on my cool points.

2. LT Patterson is a high-speed navigator. Word.

Both convoys were routed to the same location, with Robert’s convoy reaching the site first. Which meant that our convoy got lit up…gotta expend those blanks somehow. Speaking of expending ammunition… Check out High Speed. (vid)

Kyle, Robert, and I then returned to the hotel and banged out a top 10 feature list from this trip.

Top10 Features

1. MSR/ASR Overlay capability – the ability to create them and then reuse as overlays
2. 3D Mode – Essential for our Sandbox Mode
3. Distance between Checkpoints
4. Distance to the next CP from your current position on the route.
5. MGRS Gridlines (1km)
6. Checkpoint Tool – Allow the user to manually place CPs along a route
7. Convoy Routing – Routing that is limited to using MSR/ASRs only
8. Undo button – Think CTRL+Z for all you MS Office users out there.
9. Route Up – Keep the route up while travelling, providing better spatial recognition
10. Maneuver/Checkpoint Alert – Alerts the navigator to an upcoming CP or turn

Lone Apache = Cool.

- Benjamin Post (benjamin.post@primordial.com)

Last weekend, Wagner and his buddies went up to Wabana Lake and played around with the new release of Ground Guidance Handheld on a Magellan Triton 1500.  He was very impressed with how it compared to the previous version (1.4.0).  He said that the new version had the “Wow!” factor that 1.4.0 did not.    Also, three of his friends who saw the previous version, and were disenchanted by it, saw the new version and were immediately impressed with it.  Here are some of the improvements that Wagner touted:

·         The aerial imagery of the lake was extremely detailed.  There were sand bars under the water, invisible from the boat, that we needed to troll around.  The sand bars appeared in the imagery.

·         The physical buttons on the Magellan Triton were much easier to use then the touch screen on the Magellan Crossover.

·         The straight-down view The Magellan Triton was more intuitive than the angled view

·         Panning and zooming were extremely responsive.

Wagner also had a few suggestions for how Ground Guidance could be improved:

·         The user icon and the cursor icon need to be smaller as they obscure too much of the map.

·         Provide more contrast for the screen so that it more readable in broad daylight.

·         Support adding a place by a single button click.   Many fishermen like to mark the place where they catch fish, and when they catch a fish, they are too excited to want to go through several menu screens in order to mark the place.

·         The orientation of the map on the screen needs a more clear indication.

·         For fishing, it would be nice to have the GPS alert the boat driver that the boat is coming too close to shallow water or weeds.

Thank you again, Paul, for your feedback!  We look forward to making further improvements in the next version.

Participants: Andrew Seelke and Andreas Robinson

Where did you go?

• Vadnais Snail Lake Regional Park, Vadnais Heights, Minnesota

What did you like?

• Trail data was extremely useful, and seemed to be very comprehensive.  Routes following trails performed extremely well.
• Route at one point cut across a marsh area between trails on opposite sides.  Shortcut was actually quite a bit faster than going around, however, only viable in the winter.
• Backtrack feature was extremely useful, as was ability to edit and route to locations.

What did you dislike?

• User interface could use some improvement.  Supporting a degree/minute/second format could be useful.
• A “North Up” option might be valuable.  Also, an arrow pointing North while the display is following the user might be useful.
• 100K topo maps are quite low-res and not as useful as the land-cover; perhaps when using those low res topo maps, the software should default to land-cover. 

Participants: Benjamin Post and Kyle Estes

Where did you go?

• Lilydale/Harriet Island Regional Park, Saint Paul, Minnesota

What did you like?

• Impressed with the routing itself.  On a 2km path, it kept us on trails for about 1.75 km, and the last 250 meters was out in a grass/marsh area.  In this area, it adhered to the map data and led us on what the map data was showing as grass.  It was all marsh, but this shows the limitations of having to rely on accurate map data.
• Another routing comment, really appreciated the fact that it routes around difficult areas to pass.  Additionally, it was able to route us to a draw that was not visible from our initial vantage point along the ridge.
• I found Ground Guidance useful as a “digital handrail”, where it guided me even if I wasn’t exactly following the suggested route, but rather taking the route as a general suggestion and making small navigational deviations to optimize footing and avoid small obstacles

What did you dislike?

• Display screen was too glossy and made daylight operations difficult.  Even shading the screen wasn’t enough.
• On the cost grid display, combination of the glossy screen and not enough contrast between the red and green made for difficult reading.
• Switching maps took a while, and caused other functionality of the device to halt until completed.

Participants: Erik Freed and Robert Dahlstrom

Where did you go?

• Kaposia Park, South Saint Paul, Minnesota

What did you like?

• If you use the generated routes more as a guideline rather than a strict course, it works great. The routes give you a basic direction you need to follow, and if you are willing to do a little improvisation, you can resolve the short range details like finding the choice path down a steep hill or an open pass through a thick grove of trees and brush.
• There was a time when we were walking along a trail, and could see our destination at the top of a steep hill, while the route went around behind it, out of visual range. We contemplated just tackling the hill outright, but instead decided to see what cards the software had to play. When we made the bend in the route we could then see a nice gradual slope up to the top of the hill, a much easier route, even when considering its was much longer.
• Displaying track was useful for showing general bearing and indicating that we were walking parallel to the route.

What did you dislike?

• The Magellan unit took over ten minutes to obtain a satellite fix. While it was warming up it provided no feedback as to what it was doing. I didn’t like the idea that we might get to the park and have to wait around, or have to return to the office.
• The generated routes often crossed difficult, steep hills, and did not seem to recognize a walking trail through the area. On a vehicle the routes given would be virtually impossible to follow strictly.
• One route required the user to pass over a small flowing creek, and then a few yards ahead, turn around, and go back over the creek in a slightly different direction.

Participants: Nathan Vanderby and Randy Milbert

Where did you go?

• Central Park, Roseville, Minnesota

What did you like?

• Majority of routes were good
• Ground Guidance estimated that our 1.1 mile route to the “Bump Set Spike” geocache would take 22 minutes and it actually took 18 minutes
• It took two to three minutes to enter geocache; that is not too bad

What did you dislike?

• No support for degrees and minutes coordinate format (e.g. “N 44° 58.704 W 093° 11.275”) used on the Geocaching (http://geocaching.com) web site
• Cannot road route to park parking lot.  Had to use separate Magellan device to plan route to park.
• Route did not regenerate when we were way off course.

Our objective was to find candidates interested in filling our software engineering position. Decked out in our new Primordial shirts, we spent the next six hours gathering over 50 resumes from interested candidates. We figured a good outing would have been 10 to 15 resumes, so I think we did quite well. Even better, I have been blown away by the quality of the candidates from whom we have received resumes, and predict we’ll face one of those “good problems” where there are more highly-qualified candidates than we can hire.

Primordial Insider Dr. Paul Degallier sent in this picture of a 10 point buck that he shot while using Ground Guidance. Notice that he has Ground Guidance mounted to the handlebar of his ATV. Paul told Primordial “I must say it (Ground Guidance) worked amazingly while deer and bear hunting.  I could drive my ATV right to my tree stand while it was pitch dark out and with the lights off on my ATV!  A real advantage.” Thanks to Paul for sending us this great photo!