So I’m looking to buy a GPS to use for field surveying - I’m a professional engineer who is looking at doing a side business of drawing plot plans for people in my community to get approved for building permits. I go to the site, connect to the Kentucky Cors base stations, and survey property corners, utilities, roadways, general topo, etc. I then need to export the csv points lists and import them into AutoCAD Civil 3D so I can draw up the coordinately-correct survey. Does this sound feasible with this setup? Does anyone else use this device for a similar use case? I have some more specific questions below that would help me think through the decision:
How would the facet compare to a Trimble GPS in regards to accuracy, battery life, longevity, and structural stability?
How would I go about doing csv exports and imports? What are you guys using as your “data collector”? I’ve heard about SW Maps but don’t know how functional it really is on iPhone if anyone could speak to that?
What would be the process to connect to KY Cors base stations? Would it be a one time setup or something I’d have to do every time I turn on the GPS?
Has anyone integrated SparkFun RTK data with typical survey workflows (Civil 3D, Carlson, Trimble Business Center)?
How well does the hardware hold up after a year or two of use?
Are firmware updates common, and how easy are they to install?
Are you able to collect a “topo” point where it would average the reading collected over a period of time or does it just take rapid shots where it stores the first fix it gets?
Does it throw errors for tilt being off or high floats, or does it always allow you to take the shot regardless?
I’m thinking I would need the Facet, a 2 meter GPS rod, and then a bipod to connect to that GPS rod for the things I need more accurate readings on (like property corner pins). I guess I could use my phone as the collector and my computer to process the surveys. Am I missing anything?
I’m happy to answer all of your questions, but I’ll start with a question :
Do you have an existing data collector software package that you like ?
Many of the professional apps will connect to any Bluetooth GNSS Receiver.
Any of the RTK receivers will work with KY CORS network. If I were you, I’d look at the new TX2 for professional work.
Nothing wrong with the Facet, but you wont regret the formfactor of the TX2 or Torch.
What I can tell you with absolute certainty is that it’s worth your time to decide on your workflow first…the specific RTK receiver will make the least impact on your “Quality of Life”.
IE: SW Maps (iOS) will do everything you’ve questioned, but it’s a little clunky verses paid apps that are dedicated for this purpose. SW Maps has a built-in NTRIP Client. You enter your KY CORS Credentials once, and connect. You setup various layers in SW MAPS, depending on your AutoCAD workflow. After the field work, you can export a CSV file of your points (email it to yourself from the iPhone) and manually manipulate the Columns to get a PNEZD file to import into AutoCAD. [I’ve fine-tuned an AI prompt to do this for me as a cheat]
Here’s a quick summary of my workflow in this situation:
Collect the most important positions (Property corners, etc) first. I might do a 15 second average on these, at the most. Then collect linear features (road centerlines, EAO, drives, utility, etc) with 1-second shots. The same goes for ToPo. After I have shot everything - I’ll go back and collect redundant shots on the Property corners to use as check points.
You can save the Project Template in SW Maps. After a job or two, you will tweak your template to make the CAD work easier, just like any of these apps.
Oh yeah, take a look at this post too. Might be useful to you, as importing layers/linework into SW Maps (iOS) isn’t as clean as the Android version or paid apps.
I work with a Trimble R10 that has a dedicated collector running Trimble access at work. I’m looking for the most seamless functionality at little to no cost. Honestly I hadn’t seen the TX2 or Torch but having the tilt corrections would be a massive time save for stakeouts. Any idea when that might be back in stock? Which apps do you use/recommend instead?
Tilt compensation is/was a little tricky with the SparkFun RTK Everywhere Firmware.
[ Note: I don’t use Tilt, so the following might be outdated]
In normal mode, the SparkFun RTK reports the position of the electrical phase center of the antenna, and we enter the Rod Height to the ARP (+ the PCO) in the data collector software. When tilt compensation mode is active, the firmware calculates the 3D vector between the antenna phase center and the pole tip, and reports the position of the tip. The Rod Height can’t be used by the data collector software when the GNSS device is already correcting for it in Tilt Mode. So when the SparkFun is in tilt mode, you need to change the Rod Height to Zero in the data collector app.
I’m personally not a fan of tilt compensation, but I’m “old school”. I trust a bullseye level. I want my folks to plumb the rod. To me - it’s a gimmick that the survey industry pushed down to us…a “solution” looking for a problem to solve. An IMU requires calibration on every startup, but a bubble always floats Note: I’m honestly open to the idea of anyone changing my mind on Tilt Compensation…but it hasn’t happened yet.
As far as Freeware Apps, I feel like SW Maps is the most widely used. It’s very simple and easy to use when starting out.
APGLOS is a freeware surveying app with more features (and learning curve). I learned about it on this forum. I haven’t used APGLOS since the last several updates, I should take it for another spin. APGLOS will import a DXF, so that’s a big improvement over the iOS version of SW Maps. Since you’re familiar with working in Civil 3D, Carlson, Trimble… you might be better off skipping SW Maps and go straight to a more traditional survey workflow.
Whatever you decide, please share it with the community. We can all learn from your experiences.
Maybe I’m not understanding, but how would a rod height of zero provide an accurate height if I’m surveying with a 2m GPS pole?
I’m comparing the RTK Torch, PNT TX2, and PNT RTK Facet Mosaic and I know they all use different GNSS chips but what would that actually change in the field? I guess a better question - why do you recommend the TX2 above the other two?
You say that selection doesn’t matter as much as my workflow. Would my data collection/manipulation workflow change depending on which RTK receiver I select?
Remember, I haven’t played with the Tilt compensation in a while, but this was my understanding at that time:
If using Tilt Compensation with the Torch, you enter the Rod height in the Firmware + PCO (2m & 0.132m) once, during initial setup in the office. When tilt mode is activated, it beeps - and now the position is the rod tip (but only while in Tilt Comp Mode). The RTK Everywhere FW “intercepts” the GNSS position, and uses the IMU to calculate the coordinates of the rod tip, then sends it out.
I’m travelling right now and don’t have my torch me, otherwise I’d check to confirm this is still the current FW behavior. I don’t think anything has changed.
My feelings on the 3 devices you mentioned:
The Torch is a handy formfactor.
Right now, the TX2 is the latest product using that formfactor with a LG290P inside.
The Facet Mosaic is a better antenna (basically due to size), and technically the best receiver.
I can’t think of anything that will change in the field between the 3 devices (besides a snag with Tilt Comp). They are all sending NMEA to your data collector (smartphone) over Bluetooth. Your software choices are the key…Figuring out what works best for you to get data out and back into Civil 3D.
I’ve stumbled across Emlid products now as well and I’m really impressed with their website and products. It seems like SparkPNT is an electronics company that does GNSS vs Emlid being a GNSS company at the same price point. Integrated user-friendly apps and everything…
One other point to consider is how close you are to a cors station. Typically it works within 6km unless your state has a network like we do in Oregon. So if you’re too far from CORS it’s not going to work well. A Kentucky PLS I purchased a receiver from said that RTK via cors/network did not work well and he wouldn’t use it. This would also depend on what kind of accuracies you are needing as well.
For doing basic site plans a gnss will probably do 90% of what you need.
A friendly reminder I’m sure you know but I see our board here slap the hands of PEs is make sure you’re not making any claims to boundaries on your site plans. Maybe a good CYA note stating your site plan does not represent boundaries. IE if you’re tying property corners you could be offering a boundary determination…. See 201 KAR 18:150
Some thoughts as somebody who’s supporting a fleet of hundreds of Trimble R-series devices and hundreds of Sparkfuns across the US over the last 10 years:
Equal-to-favorable comparison to the Trimbles in the measures you called out.
Devices from both manufactures will deliver exceptional accuracies against control when you’re following good procedures and will deliver terrible accuracies when you’re not. If you’re asking about RMS/positional error then those will also be comparable-to-superior on the Torches for equivalent collection environments and correction sources.
The Torches are robust yall. Speaking as somebody who’s deployed dozens of Trimble R-series devices and Sparkfun Torches and Facets the Torches are most bombproof. If a R-series or a Facet hits pavement atop a 2m rangepole that device is done until you (best-case) get a new case for it. If a Torch/TX2 takes the same fall you say ‘whoopsie’ then go about the rest of your day. We’re all careful with our gear, but we also make mistakes and it’s nice to have the robust build as a backstop to good habits.
We’ve had individual R-series Trimbles in service for 5+ years. The Facets we’ve deployed seem to fail due to trauma (bouncing out of trucks, falls, etc.) at a higher rate than the R-series devices. The torches haven’t been on the market that long, but we deployed them pretty quickly after they dropped and they’ve been holding up great thus far.
I thought the non-hot-swappable battery on the Torches would be a drawback but that’s just not a factor in-practice when these rovers consistently go 20+ hours on a full charge. On the other hand the spring-contacts on the R-series battery trays are a common failure point after a couple of years of use…
If you’re really worried about long-term battery life just know that Sparkfun publishes teardown guides for their hardware, including instructions on exactly how to do battery swaps (e.g. Disassembly / Repair - SparkFun RTK Everywhere Product Manual). If you’re comfortable using a Philips-head screwdriver you can do a battery swap. This is significantly better support than Trimble makes available to anybody who’s not a distributor (i.e. you and I) and is a direct cause for us keeping lots of devices in service with a $15 part swap that wouldn’t be economical to send for repair with another vendor due to dollar cost or downtime.
SW Maps allows for CSV exports on iOS. I’d recommend downloading the app and spending a few minutes poking around - odds are you’ll find the export buttons and options quickly. I’ve found it to meet my needs A-OK on iOS and Android devices.
The process will largely depend on what app you use on your collector to connect to your GPS, but it’s some variation of looking for an NTRIP configuration window, plugging in a server address and account creds, selecting a mountpoint, and clicking connect. In SW maps the connection params are saved so that the next time you boot the GPS all you have to do is hit ‘Connect’
I can’t speak much to this besides a general observation that Trimble software tends to only want to work with Trimble hardware (and vice-versa). If you have a workflow you like in Trimble Business Center there’s a good chance you’ll have to sort out a new workflow in some other software.
SO GREAT
Yep. Firmware updates are generally pretty painless IMO. The two easiest ways I’ve found to update firmware are by connecting to the Torch via wifi or via USB + serial terminal.
This depends on the software you’re using, but averaged positions are available with lots of different collection softwares including SW Maps
See #7 above. I do think @rftop brings up some good points about tilt compensation that jive with my experiences with these devices. It’s tough to beat a bubble level sometimes…
I think you’ve got the long-and-short of it. I would lean towards a Torch-series device over a Facet, largely due to the robustness. We don’t do survey-quality shots at my shop, but that setup provides some terrific results for mapping-grade positions and you can collect at a brisk tempo with a good corrections solution.
Speaking as somebody who’s worked with Trimble, Emlid, and Sparkfun (along with other manufacturers) the support apparatus at sparkfun is 10x better to engage with than anybody else in this market. They’re indeed an ‘electronics company that does GNSS’, but they’ve been doing GNSS about as long as Emlid has existed. If you consider GNSS as a special case of electronics design you may even consider that a strength!
We had to learn some new software and workflows when we started deploying Facets ~5 years ago and you will have to be open to a little bit of experimentation and checking-your-work as you build proficiency with a different device. But that’s true of anytime you switch manufactures, sometimes even switching to new devices within a manufacturer. (we had to overhaul a lot of our processes moving from Trimble Geos to R-series devices)
TL;DR - We’re now predominantly a Sparkfun shop and aren’t looking at moving away from them anytime soon.
What app do you use to collect data with your Sparkfun units? The user interface of the Emlid flow app seems to be the best for true survey work and not just GIS mapping - curious what you think.
Are you saying the Emlid isn’t able to take a beating or that their support isn’t as good? What has your experience been specifically with Emlid’s products? I’m looking at the RX2 vs a Torch. I’d love the tilt - I know a bubble will always beat it but there are constantly shots in the field I can’t occupy with a pole directly above and this would at least get me a reference shot ± a few cm. I think it would also speed up my stake out process significantly.
For now, all I need is a rover that can connect to an NTRIP Cors System but in the future I might be looking to run a base/rover setup. I know in the Emlid line I couldn’t use the RX2 effectively as a base/rover since it doesn’t have a built-in radio so the communication link would be limited to sites where I have cell service - I’d have to buy 2 RS4’s to run base rover. If I’m not mistaken, the LoRa radio in the Torch would allow me to run an accurate base/rover setup in the future by just buying a second Torch - is that correct? If so, that’s a huge selling point for the Torch over the Emlid RX2.
I just feel like SW Maps,Q Gis, etc. feel like GIS data collection and might not work great on ios. Emlid has built in survey work flows, point coding, stakeout, projection handling, and CSV imports/exports. Does SW Maps, Q Gis, etc. actually have all of that? Is it as seamless?
