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i-gotU USB GPS Travel Logger GT-120
RsH
I received an evaluation copy of the I-GotU GT-120 USB GPS Travel Logger yesterday. Part of the deal is that I supply my evaluation data to Mobile Action, the company in Taiwan. The other part of the deal is that I am doing this partially for Laptop GPS World, so I will be posting my findings here as well. The device is about the size of my thumb and weighs 20 grams.

My first email on the device was as follows [with editing to remove non-relevant info]:

Go to Product Information > MobileAction to see more detail and the specifications for the product. It works well so far, but one day is not enough time to cover everything it can do, and it can do LOTS!

[August 26, 2009 - I have posted an update. I have also inserted amending information below where I believe it useful. - it will say '2009-08-26 update'.]

The device was easy to use, and the software and driver easy to install. Note that I did have problems with the mini-CD because of the way my desktop is positioned, but that is more my problem than theirs.

1. The warning about having the arrow side up on the connector end of the USB cable is interesting, but because the connector is molded with one of the connectors wider than the other, it only goes into the unit one way, which is with the arrow side up. However the documentation does not warn one to look at the little plastic plugs that go into the holes on the device, so it would be easy to overlook that and try to force the connector in the wrong way and break off the connectors. Why not mention that fact in the instructions as well as mention that the arrow side should be up?

2. The software MINI-CD fell into my desktop computer's DVD drive, since the DVD drive I have in it is vertical [on its side] and not horizontal. I had to fish it out with a bent coat hanger and was able to load the software only because I happen to have an old SCSI attached external Yamaha CD drive. If I had not had that, I would have had to relocate my desktop computer so that I could turn it 90 clockwise and have it with the DVD drive horizontal. You likely are assuming that everyone has their DVD installed in a horizontal manner... and that is not the case any longer. The 134MB on the CD would easily fit on a 250MB SD card, which today is far more likely to work with ANY computer, including a netbook. You should consider supplying the data on a small SD card instead of on the mini-CD.

[2009-08-26 update - download the software from the MobileAction site instead, onto the unit, and install that way. You then do not need the DVD or need to copy to an SD card or a USB key. That also addresses the issue below in 3. re the netbook and loading the software.]

3. If I only had a netbook computer, I would not be able to load the software at all, as netbooks do not have DVD or CD drives. I would need to transfer the software to a USB key or to an external Hard Drive or to an SD card to be able to load from one of those, while if the data were supplied on an SD card that would not be an issue.

SD card readers that plug into a USB port on a computer are very inexpensive, when compared to external CD or DVD drives.

I compressed the CD to a rar file that is about 130MB and will use an SD card with that RAR file to load the software on my netbook, which as both Streets and Trips and Street Atlas already installed.



3. I cannot set the program to put the GPX file into one of my 'My Documents' subdirectories, which is where I want that file to go when it is produced. Your program insists on putting the gpx file in a directory that is NOT easy to get into... namely:

Documents and Settings\xxx\application data\mobile action\atrip

when I want to use:

Documents and Settings\xxx\my documents\mobile action\atrip

Saving in "Application Data" subdirectories is NOT exactly conducive to my use of the data with other programs, such as RouteConverter, which allow me to edit the data much more easily, and to find errors in the tracking. I have, instead, created a shortcut to YOUR choice of directory and am using that to find the files I want to use.

[2009-08-26 update - the latest version of the software addresses this and the data now saves where I want it to. Their bin file still saves in the application data [hidden] folder, but the GPX and CSV are where I can easily use them.]

4. The unit was very simple to set up as a GPS device connected to Microsoft's Streets and Trips and to Delorme's Street Atlas but the software did not show that it was Microsoft Certified, so I had to tell the computer to ignore that fact to load the software. The unit ended up being COM7 on my desktop computer, and I have not yet tried it on my netbook.

[2009-08-26 update: works fine on the netbook.]

5. However I also note that the USB cable supplied with the unit is far too short for my use of that cable in the car, if I do not have the netbook mounted up high on the dashboard. I would need to use a USB extension cable. While the size of the cable is not covered, I suspect it is no more than 18 inches or half a meter long.

[2009-08-26 update: I tested in my car and the netbook and Street Atlas and could just stretch the cable to the top of the dashboard if I kept the netbook just under the radio on its side so that the USB port was up. The unit worked very well and I saved the track in Street Atlas format as well. However a USB extension cable would indeed solve that problem. Get a good shielded one, however, if going that route.]

6. In a number of instances the location's elevation was far off the correct value. This likely was due to the fact that it was being carried and the angle of the unit to the horizon kept changing. As I can easily correct the elevation data using RouteConverter, that is not a major issue, but an unobservant user might believe it possible to change elevation by 300 feet or 100 meters in a few feet of travel even when not driving over a cliff <grin>... and as a result do stupid things. I suggest that the written documentation should warn users that when carried, the elevation data is far more likely to be erroneous. Since OTHER devices do not even record the elevation, however, this error is still a minor concern.

[2008-08-26 update: Still applies, and is the nature of the beast. So unless you really need the elevation data to be exact, accept the values it records. When in a car they are close to correct, and IGNORE the fractions of a meter in elevation as the unit should not be closer than 3 meters in overall accuracy based on the design of the world wide GPS satellite system.]

7. Every language on the CD was installed on my hard drive, when if you had asked me which language I wanted, you could have limited the language to English and thus saved a bit of my hard drive space. I do not need Chinese, Greek, French, German, Dutch, Hungarian, Italian, Japanese or Russian on my hard drive <grin> and each file in one of those languages takes up quite a bit of hard drive space, in the end. Can I delete all these extra languages? That is not clear from your documentation.

[2009-08-26 update: all the extra languages can indeed be removed.]

8. Sync time with Server does not tell me which server you sync with. Is it the one chosen in Windows between the NIST server and the Microsoft time server, or is it a different time server? In any case, the GPS unit itself obtains its time from the satellites so that is another source of sync for the time... Which is it?

[2009-08-26 update: Sync time is with their own server, which is not as accurate, but it really doesn't matter in the end.]

9. Are you certain you are calculating the speed correctly? I believe you are not, and that the speed, which is dependent on the distance between two points, and the time it takes to travel between those two points, is not always calculated correctly. Also you do not show the speed you are calculating, or the elevation you have recorded, when I use Trip Composer and click on Waypoints, so I cannot easily tell if those values are correct or not until I load the data into RouteConverter.

<trkpt lat="43.767876" lon="-79.414719">
<ele>201.559998</ele>
<time>2009-07-20T18:10:28Z</time>
<speed>2.66</speed>
</trkpt>

is a specific record from your file. the 2.66 is supposed to be meters per second, if memory serves. Is it?

[2009-08-26 update: As of today the speed is in km/h and NOT in m/s so the GPX file speed is incorrect. See my information on RouteConverter in my August 26, 2009 update message.]

10. As for the elevation, I would suspect that rounding to 2 decimal places is likely accurate enough for ANY purpose. 201.56 meters elevation would clearly do, and save 4 digits of storage per point recorded. .01 meter, after all, is .338 of an inch! The computation of elevation based on the satellite positions is NOT that accurate, since accuracy of the position itself is not guaranteed to even be close to being within a meter of the position the device was actually at.
[A typical GPS receiver can locate a waypoint with an accuracy of three meters or better.]

11. When you simplify the trip and reduce a 13 plus hour 44000 point trip to 481 points, the green check mark is not evenly spaced, yet the logic you use to reduce the number of points from one per second to whatever you choose to use is not explained anywhere. Is it a change of direction? That is my best guess, but it is not what actually happened when I loaded the first part of the Panama Canal transit.

[2009-08-26 update: I simply turn off all their 'simplification' of the track and then get the full track with all the data to look at. This only works when one is on line. Else you need to use a program that has the map on your own computer.]

I loaded a portion of the Panama Canal transit that had about 9000 points, ending at the first set of locks. The program simplified that to 3 points, or effectively a straight line over land and water... NOT where the ship sailed. I had to turn off the 'remove redundant waypoints to get the track back to the curved track it actually was from the straight line generated by the removal of all but 3 points... That left 9009 points and removed only something like 17 points!

11. One of the trips I have a GPS track for is from aboard a trans-U.S. flight, that flew from L.A. to Toronto non-stop. That ideally would use an commercial airplane. The tracks from the trip that we took from Miami to L. A. via the Panama Canal were all ship's tracks, and while there are two boat icons to select, one is a sailboat and the other looks like a small power boat. No cruise ship <grin>. I note that there was no TRAIN icon, and I have several GPX files from train trips.

12. I really dislike that when I load the software it always goes to full screen and I have to manually shrink it from full screen. My screen on the desktop is 1680*1050 and I do NOT want @Trip PC going to full screen. How do I set it so that it goes to something like 1024*768 instead?

How much flash ram is inside the unit? How many points can it retain before it runs out of memory? Is there a way to tell it to only use 2 decimal places for altitude so that more points can be retained?

I have not yet tried to geocode photographs from the GPX tracks I have on file, but I will be doing that soon, to see how that works. That too may result in comments.

I am certain I will have more observations in the future... as I use the unit more.


Questions? Comments?
RsH
Content of the next email about the GT-120

Issue 1 ... I tried to use Global Mapper 10 with the GPS receiver mode of the GT-120 and it is not detected. Global Mapper will only detect a GPS receiver if it emulates NMEA-0183 v2X or a Garmin unit, and clearly the GT-120 does not emulate either of those, so it is not recognised by Global Mapper. What precisely DOES it emulate, since it is to the NMEA standard, but NOT the NMEA-0183 v2X pattern, or it would have been detected. [It is detected by Streets and Trips, Street Atlas and Turbo GPS just based on the port it uses.]

Issue 2 ... If I try to go from one use as the GPS receiver to another use the GPS receiver function is sometimes lost and I need to remove the USB connection from the 4 port unit and plug it in again, for the GPS receiver to be recognised and working once more. On occasion I have to reinstall the driver, and then the COM Port changes as well. So far it has shifted from COM7 to COM8 and has had to be unplugged and plugged in again at least 4 times. WHY is this happening? It happens when I leave one program such as Streets and Trips and move to another, such as Street Atlas or Turbo GPS.

Issue 3 ... I have found the way to get the detailed information for the points the unit does record, by asking for detailed information. It is displayed on the screen.

Issue 4 ... The speed and distance values do not make all that much sense to me when I look at them in the detailed view. Even when I was just WALKING and tracking my walk, the speeds in some cases were faster than a car travels when at the speed limit. I assure you I cannot walk that quickly <grin>... There are also far too many 0 k/m values, since you round to the nearest whole number. If I amble along at .4 k/m per hour, it shows 0! This is a case where you do need to go to one or two decimal places when you display the speed in k/m, if you are showing a WALK! I often walk with a cane, have arthritis in my hip and problems with my spine, so I do NOT run or walk quickly! You do need to consider the SLOW WALKER when you design your software!
[Saving as a GPX file and having RouteConverter determine the speed in K/M shows the correct values, incidentally, but that program also rounds to the nearest whole number, so it is useless when I am walking!. [Christian, you might want to consider how to address this issue too.]

[2009-08-26 update: RouteConverter shows 0.1 to 10.0 km/h to one decimal place now, and then goes to integer values. The walking speed in the GPX file from the GT-120 is now showing correctly in RouteConverter because it is checking to see if MobileAction is the source of the GPX file, and if it is the source RouteConverter is no longer converting m/s to km/h but is simply showing the km/h speed right out of the GPX file.]

Issue 5 ... The format the GT-120 saved in [.BIN] does not load in RouteConverter, but internally it really turns out to be a comma delimited file once the first and last lines are removed. Why are you using .bin as an extension? That is really misleading for a text based file, which this one turns out to be.

Where is the documentation on your file extensions and the formats of those files, and your interface with the computer, so that a program such as RouteConverter or Global Mapper can be made to work with these files?

Issue 6 ... I still have no idea how you simplify a track from 9000 plus points to 3 points when the track is NOT a straight line and the speed of movement keeps changing. However, I would like to be able to add my own 'green check marks' to the points selected by your algorithm, so that I can have a more accurate path and still simplify it. There does not seem to be a way that I can do that, or if there is, it is not well documented or intuitive. I can split the file, I have set waypoints, but I cannot just 'add' a point to the track by changing it from 'skipped' to 'included' - it seems to be more of an all or nothing approach, where I will almost always need to use ALL. I suggest you consider using the RouteConverter method, where someone can specify the distance between points or the time between points to simplify a file, as well as choose to delete all of the 0 movement points, or all of the 1 meter or less movement points, or whatever is most appropriate in their judgment, NOT in your judgment!
Muzikman
There seems to be very little detailed info and the "help" file that I downloaded from their site does not work.

I have tried a number of photo tagging devices and have been unhappy with all of them. Depending on the answers below, I might be tempted to give this one a shot.

Most of the short comings you have listed would really not be a problem for me as it would be strictly used for photo tagging.

How is the satellite acquisition time?
How is the battery life?
How is the battery charged?
How well does it hold a signal?
How does the device attach to you?
RsH
Quote:
Originally Posted by Muzikman
Most of the short comings you have listed would really not be a problem for me as it would be strictly used for photo tagging.

How is the satellite acquisition time?
How is the battery life?
How is the battery charged?
How well does it hold a signal?
How does the device attach to you?
Acquisition time depends on a clear view of the sky, but it seems to be between 30 and 60 seconds at a minimum, and if off for a while, several minutes at start-up. In other words, it is a typical device in that respect.

Battery life depends on the number of records you are doing in a given amount of time. The minimum is about 10 hours at a rate of one reading per second to one reading every 5 seconds. If you go to one every 10 seconds it goes to about 20 hours and if you go to one a minute it goes to well over 30 hours with a claim of about 60 hours.

The battery is charged from the USB port via the included USB connection cable, which also hooks it to the software they include.

Holding of the signal depends on a clear view of the sky. It recaptures quickly, however, if you are driving in a car and it looses the signal as you go through a tunnel. It also catches reflections off of tall buildings in a city and as a result might have a distorted route, but the distortions are relatively minor and easy to handle if you know what you are doing.

As for how it attaches to you... the blue plastic 'holder' that the white sealed device is held in has two slots on the back that you can put a 1 inch strap through, and then 'belt' it to your upper arm, if you are walking, for example. You would need to supply the 'belt' or strap or whatever, but it is designed to stay on your arm if you do that. The other advantage of that 'rubberized' holder is that it sort of holds the GT-120 on the dashboard of the car. So you can use ribbon, or whatever you choose, through those two slots to hold it in place or let the 'rubber' surface keep it from moving, or, if you have a pocket on your outside sleeve, put it into that pocket and have it work that way too. A layer of material will NOT stop it from seeing the sky.

Because the unit is very small, it has a very small antenna. So keep that in mind. It does a good job of keeping track of where it is in terms of latitude and longitude. It also keeps good records of your speed if you look into the online speed they show in their software or if you look at the speed as shown in the CSV file. At present the speed as shown in the exported GPX file, however, is meaningless. Do NOT use that speed. Instead load the file into RouteConverter and highlight all the records, then have RouteConverter add the speed. that will get you the correct speed values into the GPX file in place of the incorrect computation that the I-GotU software produces for the GPX file speed. When they FIX that computation I will be correcting all of my postings that show this error occurs, and they have been advised of that fact.

RsH
Muzikman
Thank you for the reply. It sounds promising for my need.
RsH
Update - August 26, 2009:

Overall the GT-120 does everything that it promises to do. I recommend it if you do NOT need to have a device with a map display, or if you have a notebook or netbook with a program such as Streets and Trips or MapPoint or Street Atlas that will work with a GPS receiver.

1. Rather than bother with the mini-CD to install the software, go to the website and download the latest FULL version and install that. If you have the software installed, check for the UPDATE version and download and install that. The last update was over 80 megabytes, incidentally.

2. I have found that the problem I have with the exported GPX file is that they are saving the speed in km/h while the standard for GPX version 1 requires that the speed be in m/s - I have sent Mobile Action the extract from the standard that makes this clear. However, I have also had RouteConverter [Prerelease 1.29.7 and later] checking for MobileAction as the source of the GPX file. If RouteConverter finds that on line 2 of the file, it uses km/h directly, instead of converting m/s to km/h, and will continue to do so until Mobile Action has software that follows the standard correctly.

3. The latest version of their software stores the exported GPX file and the exported CSV file in the directory I have chosen. That is no longer a problem.

4. It continues to work properly with Streets and Trips, and Street Atlas, and MapPoint as a GPS receiver. On screen the latitude, longitude and elevation are all properly displayed, as is the speed being travelled. The only time the speed is show off standard is in the GPX file, where the programmers used km/h.

5. I used the unit in a 14 foot motor boat on the Trent River while fishing and it kept a decent record of the route I took, which displayed well on the Street Atlas map of the area when I imported the GPX file into Street Atlas. It also displays well in RouteConverter, as well as their own software but the latter two require you be able to connect to the Internet, which I could not do at the cottage I rented. So Street Atlas worked much better for that purpose of visualizing where I had been, and the distance I had traveled while fishing. The track is not a straight line, but in a rocking boat I would not expect it to be able to show a straight line or a steady elevation. The angles to the GPS satellites changes too quickly in a rocking boat as it is impacted by the bow waves from passing boats, particularly larger ones and faster ones, and that in turn results in a jagged path and bouncing by meters elevation changes. The overall path is as good as one should expect in those conditions.

So overall I can safely recommend the unit. I would suggest the following:

1. Set it to update no more frequently than once every 2 seconds. Set it to one second and it may end up with two entries for the same second, even if the next second is skipped. It really depends on the precise time it gets from the satellites and one second is not always one second when it could be .98 of a second or 1.02 of a second.

2. Download the data to your computer regularly, and leave the unit connected via the cable until the red light turns off so that you know it is fully charged. It doesn't take too long, and ensures that the next time you want to use the unit it will be ready.

3. Change the file name as you save each file. The format now is yyyymmdd-hhmmss [the date and time you are SAVING the file] and I simply put spaces in so that I end up with yyyy mm dd hhmmss as it makes it easier to read and to sort the resulting files. I use the same naming convention with my ASUS R300 GPS, where I use yyyy mm dd hhmm. I also will later change the hhmmss from the time I saved the file to the time the track started. I always change the dd if the day I am saving the file is NOT the day I recorded the track, to the day I recorded the track.

Use the software they provide to geocode your photos... BUT be prepared to use Wordpad to change date and time if you have a photo which you want to geocode where you know the latitude and longitude but did not have the unit on at the time. You can manually create a GPX file with that information in it and then use their software to inject it into the photo if you look at the EXIF information in the photo to get the date and time to put into the GPX record.

If you need free software to look at the EXIF info download IrfanView... it is free and does the job easily.
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