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hydrokiwi

137 post(s)
#27-Feb-09 11:56

I need real time sub-meter accuracy GIS position and elevation data in the field (U.S.)without a Base-Rover configuration.

Looking at offerings by Trimble ( Geo - XT) , Topcon (GMS 2-Pro)and Magellan (Mobilemapper).

Interested in any guidance from others who have practical experience with the newer equipment including software and getting the data into Manifold.

I know that there have been previous threads on this topic - but would like an update.

Cheers

John

#27-Feb-09 14:50

I have a Magellan Mobile Mapper CE. This model has been replaced by the CX, but is essentially the same unit. I use ArcPad with relatve success.

The main drawback is high cost for ArcPad (Magellan has their own software as an option, but it has fewer features). The post processing feature for downloading raw files requires an activation key at extra cost.

Sometimes it locks up and needs to be re-booted when collecting streaming data. Real-time submeter accuracy can be obtained under ideal open-sky conditions; otherwise, post processing is necessary. It is not submeter accurate under trees or in steep canyons. Post processing doesn't help in these situations.

Otherwise, it is a good unit. Mine has been used in scorching desert sun and rain and still functions as it did when new. It also has field replaceable batteries and is lighter than a Trimble.

Hope this helps.

hydrokiwi

137 post(s)
#27-Feb-09 15:48

Thanks - this is the sort of practical experience I am looking for.

Cheers

John

jbgramm
236 post(s)
#27-Feb-09 16:21

Real Time Standalone Submeter GPS units are going to limited to those that have access to a NAV beacon,

or a subscription satellite correction service such as Starfire or Omnistar HP.

The Starfire service would limit you to Navcom Technologies equipment. You would also be looking at around $9000.00 entry price for a system.

Trimble has the Geo HT which claims submeter but I have my doubts that you can rely on that accuracy 100% of the time. You are looking at about $7000.00 plus to get into these units. I have seen them cheaper, but I am including software cost.

Magellan, Trimble and several others make NAV beacons for their handheld GIS units that will approach submeter accuracy most of the time, but it isn't going to do you any good up in North Dakota unless there are navigable waterways. In other words, it is designed for work down south or along the coasts more than it is for inland work.

Trimble will give several field data collection options. I feel that Terrasync would be the easiest to set up.

Data Dictionaries are a great thing.

ArcPad is an alternative that would export shape files directly. You would have to postprocess Terrasync with Pathfinder Office to export a shape file or other type of drawing file since the data is stored in a Trimble .SSF file that would need to be converted for use elsewhere.

Magellan has the Mobile Mapper Series as well as the Promark 3 series.

I own a Promark 3, and while it can be quirky at times and the Mapping software is rudimentary at best, it has been very productive.

I am not real thrilled with Mobile Mapper Office and the hoops necessary to process the field data, or the steps necessary to upload the unit with existing data, but that is just me, and I am always in a hurry.

(In other words, it has an overly busy workflow for me)

I am going to demo a Bluetooth dome unit next week with a satellite correction service subscription.

The dome does all of the position calculations internally, then transmits the position to the data collector.

I intend on interfacing the dome with my rugged tablet running both Manifold, and Geo Tracker in Mapinfo to see if this will be a viable solution for higher accuracy mapping and possibly staking.

The GPS manufacturer is claiming decimeter accuracy with the subscription service, I will let you know how it turns out.


Just Remember, You are unique, just like everybody else!

LeRepère
153 post(s)
#28-Feb-09 06:59

Look for SxBlue from Geneq at this address : http://www.geneq.com/catalog/en/sxblue2_fr.html .

I work with SxBlue since 3 years. It give a good sub-meter performance. I used them in Canada, Haiti and Morocco.

vincent

1,972 post(s)
#28-Feb-09 08:20

Yes, SXblue is a good product. And Geneq's customer service is good. It can be used in ArcPad or with Genq's software, on a Pocket PC or other handheld device. I like it.

LeRepère
153 post(s)
#28-Feb-09 13:13

Worh well with Manifold too on Tablet PC

hydrokiwi

137 post(s)
#28-Feb-09 15:29

Thanks for your help

How much do they cost?

How good is the elevation accuracy with a precision antenna under clear sky conditions since it looks like it uses WAAS.

Cheers

John

normko2 post(s)
#22-Mar-09 20:33

Hi, I'm also in the market for a GPS (non RTK) something very portable that will give me accurate elevations ie; sub-meter minimum or better under tree canopy. I've tried a Trimble Pro XRT and it did quite well most of the time expecially in the open, however some shots did not look right. Overall not reliable 100% of the time. I will demo a Topcon GMS 2. I want to compare to see how the GMS 2 does vs the Pro XRT. The GMS 2 is much easier on the budget so if I can achieve much the same precision that may be the way to go. Does anyone have any experience with such equipment to get elevations they could share??

Norm

LandTek
2 post(s)
#01-Apr-09 10:26

I have been using a Hemisphere A100 smart antenna and logging data with a TDS Recon operating SOLO Field. It consistently provides submeter observations in the clear using WAAS corrections. However, mostly we use it in the woods under difficult canopy conditions. It has performed well, with accuracy in about the 2 meter range or better without any post-processing when we elevate it on a 20-foot tall survey rod.

The A100 can also log raw data for post-processing using the PocketMax software that is provided free by Hemisphere. I haven't done this, but the collected data could be post-processed for free using the USGS OPUS website service. I am not sure if this service is available outside the U.S. or if you would need to reference local corrections stations by other means and/or purchased software.

Based on my past experience post-processing data from under canopy conditions is dicey at best because you are only getting data from a few of the theoretically viewable satellites and a lot of your data simply can't be successfully post-processed. But this opinion is based on my limited experience with post-processing and may be wrong.

The nice thing about the A100-SOLO Field combination is that you get real-time estimates of your positioning accuracy and know how many satellites the unit is using. My experience is that the estimates are pretty accurate, so if you are getting junk for static observations you just cancel out your point-data collection and try it again until you get good data. The accuracy varies from moment to moment and elevating the antenna usually makes a huge difference. As can simply wiggling the receiver or re-acquiring satellite almanac and corrections data in the clear before proceeding again.

SOLO also allows you to do off-set observations from a nearby spot with better reception and adjusts your recorded point accordingly. Other factors that noticeably influence our accuracy is local leaf cover (going above or below clumps of leafy branches, weather (clouds, rain, hail, T-storms, etc.), wet leaves (bad), mission planning factors (satellite numbers and geometry).

The A100 is a combined receiver-antenna, but with separated modular systems (e.g. Hemisphere XF100 and separate antenna) the antenna used has made a big difference. I briefly compared two survey-grade antennas from different manufacturers and found a big difference in the number of satellites received (which surprised me). I would suggest buying antennas from the manufacturer of the receiver, unless only simple puck-type antennas are available.

For stand-alone mapping level (0.5-2m) accuracy I highly recommend the Hemisphere A100 receiver coupled with data collection software that allows you to see your data accuracy in realtime. This system is working good for us and is much cheaper than the excellent but pricey Trimble systems.

The entire system we are using is accurate enough that minor differences in selected datum (WGS84 vs. NAD83 and/or updated NAD83 variants) has become the dominant accuracy issue when mapping features and comparing them to base maps.

hydrokiwi

137 post(s)
#01-Apr-09 12:42

Landtek:

How much did this system cost?

Cheers

John

LandTek
2 post(s)
#01-Apr-09 16:12

The A100 GPS unit retails for $1500 (U.S.), plus $200 for a 3 meter combined data/power cable which we had to extend in a funky, do-it-yourself way. A rechargable 12-volt battery to to power it was about $35 at my local electronic shop which we taped to the survey rod. Collapsible 20 ft survey grade rods cost about $200.

You need a data collector field computer and data collector software. I got a new TDS Recon with SOLO Field for about $1,800. I think that price is now about $1500 or so. You could do it with the newer NOMAD for VGA graphics for the price I paid.

So the total price is about $4,000 and no maintenance fees. You can buy an activation code that allows the unit to be used as an RTK system with a base station for sub-20 cm accuracy for extra $$$. I don't need it.

I think you could connect the A100 to a Bluetooth adapter and broadcast wirelessly to your tablet computer, netbook or other Bluetooth enabled data collector running your favorite software or Manifold.

Does Manifold read standard NMEA GPS output? I am in this discussion group but don't own Manifold. I have been using Delorme XMap but don't recommend it.

I am using SOLO because it exports to CAD as well as Shape files and is very simple to use.

Mike Pelletier

2,122 post(s)
#30-Nov-10 09:47

Anyone have any more experiences to share on this issue? Our GeoXT is dying and I'm thinking of replacing it with a Topcon GMS-2. I've read through Trimble's somewhat desperate white paper bashing the GMS-2 and Topcon's response.

http://www.mapping-gis.de/files/Datenblaetter/GMS-2vsGeoXT_WP_MGIS.pdf

http://www.inovagis.com/downloadables/Response to Trimble White Paper.pdf

firsttube


1,439 post(s)
#30-Nov-10 10:20

check out the ashtech line of handhelds....especially the MobileMapper 100

http://www.ashtech.com/mobilemapper-100-3821.kjsp?RH=1272644205746&RF=PRUEMM100

I've used the predecessor, the Magellan MobileMapper CX for a few years now with success. The MM100 claims to be even better.


"The blessing in life is finding the torture you are comfortable with." - Jerry Seinfeld, 6/26/2013

rfriedman
243 post(s)
#30-Nov-10 11:48

Mike - I've used Ashtech/Magellan products and Trimble products for years. The Ashtech line will give you a good solid product usually at siginificant savings over Trimble products. But Topcon also makes very good units as well (our survey crews use Topcon and are very happy with them). The GMS-2 is really nice, and hard to beat the feature set (camera and laser range finder - I drool every time I see one).

Depending on your needs, you should take a look at both the MobileMapper 100 and the MobileMapper 6. We have a MobileMapper 6, and it is a cute little thing! My only complaint with it is that the screen is a bit small, and we got ArcPad on it instead of the MobilMapper software (I really don't like ArcPad - don't know why, but I find it less than intuitive, slow, and often counter productive). But thanks to the small screen, it's also very compact and easy to carry, and has a 2 megapixel camera. We also have a pair of Promark 3 units that have both the survey software (for high accuracy) and the MobileMapper software (for GIS data collection). The survey software isn't real user friendly, but I like the MobileMapper software (easy to learn/use - very simple).

We bought our Ashtechs (at the time Magellans) from iGage (see link below). They had the best prices we could find for the whole package, and really good customer service. I'd suggest giving Mark Silver (owner) at iGage a call and tell him what your needs are, and that you are looking at the GMS-2. He can make a real good recommendation on what unit would work best for you, and make sure you get all the needed accessories. He's also very upfront about what he likes about the receivers, and what he doesn't like about them (plus he is very interesting to talk to).

http://www.igage.com/mp/mm100_pm200/MM100_PM100_PM200.htm

In terms of software - I think Trimble is still the best, but you pay for it! Topcon has some real slick software now too, but the MobileMapper software is really quite easy to use and does everything you need as well. In terms of product quality for the receivers, I think they are all probably about the same. I do think that the ProMark 3 units we have are built a bit better in terms of being "rugged" than some of the newer Trimble products. The Topcons look pretty solid, but I don't know anyone who has used the GMS-2. If it's comparable to their survey units, it should be very durable.

For "long range" quality and durability, I have two old Magellan Promark X CM units at home that are over 15 years old, and they still work as well as they did when they were new. I also have two old Trimble Pathfinder ProXRS units at home that I bought used, have seen some hard use, and are as solid as the day they were made (12-14 years old). Of course that was before Trimble went to Windows CE/Mobile - the newer units just don't have the same "abuse me" feel that the older ones did.

Good Luck!!

Mike Pelletier

2,122 post(s)
#01-Dec-10 07:51

Thanks gents. Rich - sounds like your GPS man. Great advice. I'll give the MobileMapper units a look, but sure do like the GMS-2 feature set. Fortunately, we're in no rush to buy now that the ground is white for the winter.

fbestm4 post(s)
#01-Dec-10 13:29

You can take a look at the onpoz product... I have 2 trimbles and 4 Scout Pack (SubX with Archer or HP PDA). I do not use anymore my 2 trimbles because of the poor reception compare to the sub x. http://www.onpoz.com/Products/

Mike Pelletier

2,122 post(s)
#01-Dec-10 16:07

Thanks for the tip. Interesting that it would have that much better reception in canopy. That's a really import part of the buying equation to consider so glad to know about this unit.

jimsinclair

142 post(s)
#01-Dec-10 16:25

Mike,

Drop me a note at jimDOTsinclairATtx-esaDOTcom.

I may be able to arrange a free trial for one of the units that has been discussed.

rfriedman
243 post(s)
#01-Dec-10 16:04

Yep - the GMS-2's are pretty much the current ulitmate GPS geek toy .... umm .... I mean ultimate GPS data collection tool. If you need to collect location data in places where GPS reception is poor, or get a power pole in a back yard with a big dog, the integrated laser range finder could be very handy.

volker

1,086 post(s)
#20-Jun-11 06:15

Something new on this in year 2011 ?

We are looking for a real time submeter gps with accuracy between 1-3m

under canopy. We need this for inventory points in forest.

Thank you for the feedback.


http://www.thegisservicesector.de

Mike Pelletier

2,122 post(s)
#20-Jun-11 16:08

Nothing new but we just recently purchased the Mobile Mapper 100. I don't have much experience with it yet but it does get submeter accuracy real time in our area. It's quick to acquire satellites and works well in trees. Interestingly, I'm told Trimble has just bought Ashtech. Apparently, they were losing too much market share. Also, I heard many folks have had lots of trouble with Topcon's GMS-2 with poor support when trouble arise.

BCowper


1,275 post(s)
#20-Jun-11 16:31

I'm told Trimble has just bought Ashtech.

I just found this news release, from back in April. One of our Ontario offices just acquired several Mobile Mapper 100 units and we'll likely follow if they prove to be good devices, as long as Trimble doesn't put up their prices - the 100 doesn't look that far away from the GeoXH in accuracy, but there's a big gap in pricing!

volker

1,086 post(s)
#20-Jun-11 20:42

Thank you for your answers.

The Mobile Mapper 100 falls in our narrower choice.

I hope we get at first a device to test directly.

If i had my experience with it, i will post it here...


http://www.thegisservicesector.de

volker

1,086 post(s)
#27-Nov-11 10:10

No news from me...the project was stopped before it begins...

But always interested in experiance from practice.


http://www.thegisservicesector.de

firsttube


1,439 post(s)
#25-Nov-11 20:40

I'm wondering if anyone has had any experience with the MobileMaper 100 yet?


"The blessing in life is finding the torture you are comfortable with." - Jerry Seinfeld, 6/26/2013

BCowper


1,275 post(s)
#25-Nov-11 21:34

I'll see if I can get my colleague from Kitchener to pass on her comments about them next week.

hydrokiwi

137 post(s)
#26-Nov-11 04:10

I started this thread some time ago.

I ended up buying the ProMark 100 with the L1 Antenna.

I like the Unit and the GNSS solutions software for post processing data.

I'm an engineer and need decent elevation data which is tough with SBAS systems or non-RTK GPS.

The Promark works well as a general mapping device with sub-meter accuracy and with post processing you get can get cm order accuracy if you have some decent CORS stations nearby.

I also bought the FastSurvey software which is a version of SurvCE - which also works well.

I have the Lasertech 360 laser clinometer which can be hooked up to the Ashtech via Fastsurvey and take offset shots to spots that you cant occupy. I dont have that set up yet. Thats important for me too to take shots where there is no GPS signal or on the other side of a river or canal that I cant get to.

If I was doing it again I would probably spring for a Promark 200 setup as a network rover or an RTK pair - so I can get real time precise data for stakeout etc. Post processing doesnt work for that sort of stuff.

If you want more info check Mark Silver's info pages at IGAGE ( you'll find it with Google) . He writes a lot of stuff about survey grade GPS units. He is also a good person to call for practical info.

Good Luck

John

danskav1 post(s)
#18-Sep-14 18:44

Our organisation have 6 Mobile Mapper 100 and 4 mobile mapper 120.

Mobile Mapper 120 (around 4000$ with Glonass Option)

And a Trimble Geo XT (around 8000$ glonass option)

We use it to do forest inventory, the goal is to send people where we want them to go and not let them choose an area where there is less trees to count (because garmin or other old gps without glonass were not as precise and they had a distance flaws).

95% of the time, points are below a 3.5m distance of the intended target for all brand of gps after post-processing at the office (in the woods). Sometimes 5cm, sometimes 3.4m, it all depend of a variety of factors (weather, terrain, time of day, distance of the base for the post-processing correction, number of satellites, etc...)

But the best of those kind of gps is thier accuracy in the field. You go right on the target.

Best and bad of each GPS:

Trimble geo XT = a tank, it's heavy and big but handled, it never miss to record data for post-processing. It's a little difficult to learn to use it but when you are use to it, you like it. Problem : Cost a lot, the internal software as a annual licence fee to upgrade it (around 600$-800$). Same for the post-processing software Trimble geo office (expensive annual licence fee).

When you record, it record everything (bad or good signal) and you sort it with the post-processing software.

it use waypoints thay you create with the post-processing software, that it's kind of pain in the ass to create.

Why we have just one, because of the price.(and none of the companies that works with us bought it for the same reason) We can have 2 MM120 for the price of one XT.

------------------------------------------------------------------------------------------------------------------------------

MM100 (ashtech) and MM120 (spectra precision/trimble) are similar, the only difference is the présentation of the internal software. A littlle smaller very good GPS with SBAS/GLonass features.

The good is you create your target (waypoints) in arc/gis and you put the shapefile in the GPS, for arg/gis user it's the best. Easy and user friendly. And the result is a shapefile/points with data for post-processing.

You can choose your PDOP maximal and the GPS will not record the signal above it.

For us, in the woods, we set up a pdop of 4 and 99% it works well.

If we dont get a signal, we put it at 6 for getting a position (rare)

The bad, is that sometimes (not often) it bugs for unknown reasons. you have to use it seriously, step by step like a robot. And sometimes the data for post-processing is missing...but never the shapefile/point before post-processing.

The internal software is free of licence and free for upgrating as the software for post-processing.

-----------------------------------------------------------------------------------------------------------------------------

I recommand all those GPS. Very accurate.

We use them for a specific purpose but they can do lot more .

breadman
5 post(s)
#20-Jun-11 23:02

Ive been using a Geo XT with a Trimble Yuma tablet. Manifold works ok in the field which saves on cost of buying the trimble software. Takes a while to pick up satellites however compared to the built in gps and reception is not as good. Im using it in northern Mexico.

Ive also tried the mobile mapper 6 which I didnt likea as the screen was small and hard to see in sunlight, also tried a trimble geoXH with the trimble software which worked well but had the hassle of having to export data back to manifold...

I prefer the Yuma as it runs window 7 and has a decent screen size.

volker

1,086 post(s)
#19-Sep-14 13:35

We have a Trimble GeoXH 3.5G with full software (on the Trimble and on PC) but this is a very expensive choice (12.000 EUR).

We have different Data Loggers (in the moment don`t know exactly which ones) and 6 Garmin GPSMAP 64s with extern antennas (from different customers).

We do in the moment a long time test with this units to look what`s the best one for us (forest inventory with accuracy of 5 meters).

My personal experience with the Trimble: the weight is not acceptable if you hold it in the hand (better use a tripod). The software isn`t user friendly. The accuracy is good if you get EGNOS (WAAS). Perfect if you use RTC (here in Germany it called SAPOS) here accuracy about 10-50cm. But the most time in forest you don`t have SAPOS. And EGNOS sometimes lost. And without them your accuracy is between 6-12 meters in best case and sometime up to 30 meters. This isn`t acceptable.

Postprocessing in the moment we didn`t use....

About the data loggers i can`t report something, my colleague do this test. But more if he exploit this.

Now to the Garmin 64s it use GLONASS and EGNOS, too. For the price (about 400 EUR) the most time you have an accuracy with extern antenna (i use a tallysman antenna (100 EUR) with a mirror on a tripod). The most time i have accuracy about 2-5 meters (with antenna) sometimes up to 7meters but not worse with antenna and EGNOS on. Without antenna its not so good. But for the price and the handling of this unit it`s perfect if you don`t needs submeter. But you don`t get some metadatas logged (a huge advantage of the TRIMBLE software) like number of sats, dop and so on.

The test will takes till the end of the year. If it ends i can report here the real datas not my personal opinion....

P.S.: i calculate the accuracy of a known coordinate (a markstone) with the logged coordinates of the unit


http://www.thegisservicesector.de

volker

1,086 post(s)
#19-Sep-14 14:08

a notice on the accuracy of the Trimble:

it wasn´t so bad i report above. I looked into the datas. My report above was the accuracy of the display, now i have load the datas into manifold and the accuracy without EGNOS about 1-6 meters and with EGNOS about 0.5-2.5 meters. On my test i don`t have SAPOS because there is no reception of SAPOS.

It seems if the reception is to bad (like i report) the Trimble don`t use it for average determination of the coordinates.


http://www.thegisservicesector.de

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