Looks like you solved it. ; )
I had a follow up question - we’ve been having issues with our EM38 survey equipment dropping via bluetooth. After testing multiple computers and a couple EM38s I’m wondering if the RS2 is sending too much data over bluetooth for bluetooth 4.2?
People have been using EM38s + GPS for over 5 years now, yet we’re having a lot of dropped connections with the EM38. I’m wondering if its possible that the RS2 is sending a lot of data that the computer (we’ve tried multiple) is losing connection with our survey equipment because of it.
Does this make sense?
Bluetooth 4 is supposed to be good for ~305kb/s of throughput.
In layman’s terms, that is about 20 typical text terminal screens full of data per second.
As a rough guess I think you’ d be consuming maybe 1/20th of that with ReachView set to a 1Hz sample rate. (test yourself to be sure)
What is the distance between each connected Bluetooth device and your host computer a tthe time you experience problems?
If one is very close and the other not so close then you could be experiencing RF saturation problems.
The computer is at the front of the ATV, the rover at the back (~4 feet apart). The EM38 is 6 feet behind the rover (and about 10 feet behind the computer) all in a line.
So in order of proximity, you have:
- bluetooth host
- does the dropout behaviour change if the computer is raised to head height and off to one side? (to preserve line-of-sight to the clients)
- would a USB extension cable with USB bluetooth dongle help the connection by relocating the bluetooth host to back of the ATV?
- Internal combustion engine with electronic ignition
- are you running a resistor-type spark plug? (for less electriclal noise)
- does the dropout behaviour change with engine on/off?
- Human body
- in the line of sight
- does the dropout behaviour change with the human is removed from the line of sight?
- Reach RS2
- bluetooth client
- bluetooth client
- is the metal chassis of the ATV between the computer and the EM38?
Can you download a Bluetooth app that shows the RSSI or some other signal quality/strength data for each client? (maybe even for throughput - to answer your other question)
@bide, thanks for the detailed questions.
I’ve moved the EM38 to a foot away from the computer (on the back of the turned-off ATV) and it had no impact. In this format, my body was potentially between the RS2/EM38 and the computer, but otherwise there was nothing in between. All 3 pieces were on the ATV with the EM38 on the back of the ATV, the computer on the front, and the RS2 on a pole on the ATV.
It has occurred to me this is an issue because the bluetooth dropoff happens primarily when moving on the ATV. When I’ve tried carrying all 3 elements on my person or left the equipment running while on the turned-off ATV and dropouts did not happen.
That being said, turning on the ATV and letting it idle does not seem to cause the issue. As well, once the bluetooth has dropped often turning off the ATV or moving the equipment around does not allow it to find the EM38 via bluetooth.
This is not a variable we thought of testing. I will see if this affects the issue.
You are correct on the ordering of proximity. The metal chassis of the ATV is between the EM38 and the computer.
I will also download a bluetooth RSSI app and check the signal strength.
Lastly, I have attached a photo showing our old wired setup, but it should help with visualization. With the bluetooth setup, we have the computer in the bin on the front and the RS2 on a pole on the back of the ATV. Everything else is the same.
Well, with the metal rack under the computer and the metal handlebars and maybe/maybe not the metal spooling rig on the back of the ATV (but certainly the metal frame. Why not just stick a good (or beefed up bluetooth unit out the back of the quad and route a USB extension cable up to the front mounted computer?
This way the antennas can all see each other directly without any metal inbetween. I think that is the best chance for success.
The other thing is the ATV ignition system (probably located somewhere between your knees). Even though it doesn’t seem to affect at idle, it might be that bluetooth can find a happy channel without interference when the the ATV is idling, but when you are driving and the throttle is moving up and down, maybe the interference is more broad spectrum and none of the bluetooth channels are free of interference.
I would put someone on the back (sitting backward and holding the computer). If that works without dropouts, then mount the computer back there or leave it up front and run the USB extension to an external bluetooth adapter out back.
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Have you managed to figure out what may cause the Bluetooth dropoffs? Were @bide’s suggestions correct?
If not, may I ask you to specify what’s the update rate frequency was on Reach RS2 when it happens?
We haven’t tested bide’s suggestion yet as we sent the EM38 unit in for repairs. We will test it as soon as it gets back.
The update frequency for the RS2 was at 5hz and 1hz, both frequencies created issues.
Please, keep us updated regarding these tests.
For 6 years I had Leica GG03 and handunit CS-10!
It always connected via bluetooth, never WIFI, that can be disturbed by other wifi,like it is now with RS2!
Bluetooth is more or less on the same frequency band (as classic WiFi, 2.4 ghz), and will be disturbed just as much as WiFi, if there is are enough interference.
Rs2 still connects to FG via bluetooth.
Huh? Emlid Reach products connect to data collectors mostly by Bluetooth or serial connector to get NMEA data stream… not WIFI.
You use WIFI to connect to the Reach product using ReachView to get to the product’s settings. Which can also be turned off after doing so to save battery.
A post was split to a new topic: ReachView updating