GPS under canopy

Well, I as a matter of FACT do not know.... I cannot get anybody to do do a comparison. Please note, that IF you can line me up, for a day of "trials" that I will make the effort, to participate.
But, there is another issue, that I would know about, and other Javad users would know about, but, the 'others' would not know about.
If you remember back to the days of walkie talkies, 2 way radios, there is a STANDARD mechanism, for using them. Turn on, then turn the squelch knob, until you hear static, then back off, until it is QUIET. That is the setting you use, MOST of the time. (on this level, ALL gps is basically equal, from a USER standpoint).
BUT, when the radios are real far apart, that setting won't work. You HAVE to open the squelch ALL the way, to hear FAINT signals.

So, in my words, the Javad is running FULL TIME, with the squelch WIDE OPEN, and has enough filters, channels, and engines, to "Weed out" the bad signals, in seconds. The Javad HAS 864 channels, (in multipath environments, the number of signals, from each satellite, grows exponentially).
As I READ the datasheets, early TRIMBLE R-8 had 72 Channels. (See Page 2, left hand column, about 1/4 down from TOP of page) https://solutions.seilerinst.com/Portals/1/Catalog%20Items/Trimble/R8GNSS/R8GNSS%20datasheet.pdf

Then, later Trimble R-8's had 220 channels (See page one, on the left, under "key features")
http://www.inlandgps.com/Products/R8M3%20Datasheet%20200911.pdf

I mention this difference between R-8 units, to say that when comparing units, WHICH model you get, you may not get the SAME components.

Now, enter the Trimble R-10 units. According to their data sheet, found here:
https://community.trimble.com/docs/DOC-1041
(You have to go to this page, then click their link, to get the datasheet)
The R-10 units have 440 channels.
The more channels, and processing power you have to manage all the bad data, coming from severe multipath environments, the better your final product data will be.

Javad has AUTOMATED this "weeding out" process, so that you can RELIABLY, CONSISTENTLY, get the correct INIT, EVERY TIME, if you leave all the settings intact. NO other unit does this. It sits, in the abyss, and does it's own RESETS of init, and slowly chews through, and get it RIGHT EVERY TIME.
It's like a 4 man crew in a box. It's better than Kent Mc. in a box. If you need accuracy down tighter, run 3 shots, and average them. (It has a weighted average program in it).

Is the TRIMBLE a good unit? Yes, and IF you work for hwy dptment, and or other places, where you need the DC to work with a robot, and GPS, and back and forth, the Trimble may be a better choice for you. Construction, and the like. Or, maybe one of the other brands.

But, if you are a boundary surveyor, and want to work with RTK for everything, and you can live with a few hundredths LESS accuracy than using PURE static GPS, and an accurate Total Station, or Robot, to shoot into the woods, but you CANNOT live with a bad INIT (Bad init is where RTK gives errors in the magnitude of <0.15' and UP, (usually up to around 12') then the Javad unit makes more sense.
My closing comment is: Get a demo from every major vendor that you are considering.
If you want a demo of Javad, I can help.
I'm proud of my equipment, and generally like to see good surveyors get good gear.
BTW, what data collector(s) are you FAMILIAR with?

I don't work for Javad. But, I wish I did.

N

"Is the R10 better and more reliable under canopy than R8GNSS?"

In my experience, yes. Trimble has done away with the fix/float solutions of the R8, which I found to be the biggest source of bad 'fixed' solutions. The R10 doesn't give a fixed solution but rather a precision as it winnows through the solutions narrowing down the precision. I'm amazed at the places it will work, but it's not perfect, which is where I really like having the option to switch to the S6 when I have a lot of shots to collect and I might have to wait 5-10 minutes to get each shot with the R10.

Comes down to production I guess. For volume and efficiency I chose to go with Trimle. Not knocking Javad.

I've used R4-3 GNSS under canopy to verify monuments set in the 1970s but the Record of Survey was never filed. They checked very good but it may take several minutes for them to fix after the rover is setup on the monument. This is on a ridge. Down in a canyon in canopy it may never fix.

I recently purchased a couple of Carlson BRx6 GPS units. I now get fix under, or near, canopy where I never could before, but you had better have some way to verify those compromised shots. The Carlson BRX6 has a new feature called "Fixed+" that happens only when the dual independent GPS units in the head agree with one another. When I get the "Fixed+" indication for a shot, it has always checked and been right on. After many years of extensive experience using GPS in the Portland, Oregon area, you had better be careful trusting a compromised GPS shot. If 0.2' +/- horizontal and vertical accuracy is good enough for what you are doing, even though it appears to be fixed, it might work. If you have an important monument or position to collect under canopy, I personally wouldn't trust a GPS shot without a verification. In my opinion it is better to set 2 or 3 good solid GPS control points in an open area and use a robotic instrument to tie in that monument.

As a surveyor I feel the newest GPS technology is one of the best technology break troughs, ever. But, the real art to using it as an everyday tool, is to know it's limitation. GPS is the first thing I bring out of the truck on a new job, I use it to set all my network horizontal and vertical control, and then collect all the shots that are GPSable, then I start using the the robotic instrument.

Frank Willis, post: 421381, member: 472 wrote: Looking hard at upgrading to Triumph LS, but not sure Triumph is any better in the woods under canopy than a Trimble from what I have seen from several emails. Have any of you used both the R8GNSS and the Triumph LS to note any difference under canopy?

Looking at their videos under canopy, I think my R8GNSS would get fixes there too. That single thing is the main driver for me considering upgrade.

Is the R10 better and more reliable under canopy than R8GNSS?

With advances in technology I think the questions have changed. You shouldn't be looking for equipment that will get a fix where something else will not. they will all get a fix just about anywhere (at least on one engine). The pertinent question now is who has the better methods of determining whether a fixed solution is good or not, and how good it really is.

The javad hybrid system is the only thing I've seen so far that meets my standard of skepticism. You need both javad base and rover to utilize this. If the rtk and ppk don't match within the precision I've set up, then it's a bad shot. Period. No more guessing (er, professional judgement).

Maybe the others have something similar I'm not aware of.

Duane, Javad sales.

Duane Frymire, post: 421929, member: 110 wrote: The pertinent question now is who has the better methods of determining whether a fixed solution is good or not, and how good it really is.

Duane nailed it!

Wouldn't one have to define the nature of the canopy?
From the many posts by javad enthusiasts here for the past year, it looks like the LS is the industry leader.
Also the proliferation of long time posters here who have become (or want to become) Javad sales reps is impressive. I am not aware of any incentives that they receive for their comments.

I have been really busy the past few weeks out using the LS so I haven't posted much. I have been in the heavy steep mountains doing a boundary survey of some really old property. I did not have to use my robot for any of it. Yeah it takes a little bit of time to feel confident in harsh environments but I'd rather hang out a bit than traverse robotically. I'm not near as tired at the end of the day, which is good cuz I got maps to draw.

[SARCASM]All I ever get to survey is old property[/SARCASM]

Robert Hill, post: 421965, member: 378 wrote: I am not aware of any incentives that they receive for their comments

There's an incentive in that generating interest will tend to generate sales, but at the same time I believe they're all genuinely enthusiastic about the products and use them in their own work.

I was in the field this morning and having trouble with a localization, so I called Shawn (though I could have called John, or Adam, or one of the others). He connected to my LS -- which was connected to the internet through my phone -- saw what I'd done wrong, and had me going again in about 5 minutes. That kind of support is hard to put a value on.

Jim Frame, post: 422041, member: 10 wrote:

I was in the field this morning and having trouble with a localization, so I called Shawn (though I could have called John, or Adam, or one of the others). He connected to my LS -- which was connected to the internet through my phone -- saw what I'd done wrong, and had me going again in about 5 minutes. That kind of support is hard to put a value on.

That's pretty amazing! It would appear that no one coukd rival that customer service. Sounds sort of like a co-op concept of user and product rep support which would be very progressive in action.
So if you care to mention, what wrong did you do?
I recall localization comments before.

Robert Hill, post: 422042, member: 378 wrote: So if you care to mention, what wrong did you do?

I had selected the wrong coordinate system for the localization, and that played havoc with the coordinates. Changing that selection made everything work the way it was supposed to. (That's an abbreviated description of the situation, but I don't want to type a more detailed explanation on my phone.)

J-Field is a very versatile application, and with versatility comes complexity. I'm still a relatively unsophisticated user, so I sometimes get tripped up by stuff that more experienced users know like the back of their hands. Being able to get one of them on the phone just about any time is very helpful.

That was a lot of fun, Jim. I know I sell the stuff and I shouldn't be surprised when things go right, but when I'm sitting in my office in Kilgore, Texas, and looking at your receiver screen while you are in the field somewhere in California, working through a question or issue, it blows me away.

I have the CHC X91Bs from IGAGE they work better under canopy than anything I have ever used or seen, that being said I think that most of the Units by various brands are all, pretty close but the difference is how many constellations they pick up and use. This stuff I have came with all in view and will add news satellites as they come on board at no charge. I have had Trimble for years and they don't do anything for free. The other consideration for me was price. How long before a GPS system becomes obsolete vs price.

Nate The Surveyor, post: 421387, member: 291 wrote:
It's better than Kent Mc. in a box.

N

Ya, maybe, but it's a lot more expensive and can't tell half the stories he does nearly as well.
for now, I'm sticking with my KMC in a box!

I was able to use the R-10 some, and have used the R-8 more. I don't have a way of conforming this but, it seems the R-10 worked a faster solution in urban environments where multipath errors or obstructions occur. I don't know the 'whys' of it though.

Williwaw, post: 421414, member: 7066 wrote: In my experience, yes. Trimble has done away with the fix/float solutions of the R8, which I found to be the biggest source of bad 'fixed' solutions.

And shooting crap for thirty seconds doesn't make it any prettier

Robert Hill, post: 421965, member: 378 wrote: From the many posts by javad enthusiasts here for the past year, it looks like the LS is the industry leader.

If you go to the web sites for Trimble, Leica Topcon and others, they also claim to be the industry leaders.

rfc, post: 422070, member: 8882 wrote: Ya, maybe, but it's a lot more expensive and can't tell half the stories he does nearly as well.
for now, I'm sticking with my KMC in a box!

For those of you who want to, you can change the sounds the Javad makes.
You can change the sound files, for it.
And, you can have BOTH worlds....

Change the sound file, for when it gets a shot, to say stuff like "Best Regards", when it gets a shot. (I don't know if Kent would make us the file...) You'd REALLY have it then...

And, in memory of Richard Schaut, it could say "Dippity Idiot", when you reject a shot.....

There is some real potential with these sound files....

🙂

N

Javad is a very interesting technology.

Can you provide me link(s) or videos showing how the technology performs under heavy canopy? How about support if I am located in the Philippines? How about the price compared to the leading brands like Trimble, Leica, and Topcon?

Thank you.