DJI M300 and RS2 workflow and limitations

We are looking to get a DJI M300 and P1, with an added Base/Rover for RTK/PPK and GCPs.

We have considered the DJI D-RTK 2 and Emlid RS2. I understand the Emlid RS2 will give us great flexibility and use.

From what i understand, the DJI M300/controller can only connect to an NTRIP network (wifi) for RTK, meaning that the RS2 would have to be in close proximity to the controller, and require cellular reception, is this correct? Or Occy sync if using the D-RTK 2

We also have a scenario where we are working on a site that has a Topcon G5 that a contractor is (presumably) broadcasting over LoRa, for GPS guided machinery. We were hoping that we could connect to this, but it seems not. How would we use the RS2 in this instance for RTK.

For PPK i understand we would just connect the RS2 to the topcon G5 and use a known point to record RINEX while we fly the M300.

Yes the RS2 will outperform the D-RTK 2 easily in use as a rover, repeatability and battery life. You can go completely off grid if you have two. D-RTK 2’s don’t work together as a base and rover over LoRa which doesn’t make any sense because they can be both and the drone is a rover. It just can’t talk to itself? Any modern receiver can i/o via NTRIP at this point. Focus you search on Emlid Caster and newer Local Caster which I don’t know much about.

1 Like

Hi Brocxen,

As Michael mentioned, we have a feature called local NTRIP Caster. It’s a way to send NTRIP corrections to your drone controller via the base’s Wi-Fi hotspot. Our DJI users confirmed that it works fine for them. So, if Internet access is unavailable, this feature can help.

Our LoRa can work only with Reach devices. But if you have a second receiver from another manufacturer, you can use a couple of external radios for the base and rover. If the Topcon G5 can output GPS observables and ARP coordinates in RTCM3, it should work well as a base for Reach.

I’d also recommend our new post-processing software, Emlid Studio. The latest version is capable of geotagging photos using timestamps generated by DJI drones.

4 Likes

Hey Kieran, you can create a wifi network and extend the range quite a bit. I get 40m between rs2 and wifi router and 250m from router to m300 controller (without obstructions)

I can confirm that this configuration works and is quite straightforward to setup. I even recommend it, but I wouldn’t go as far as (/u/chascoadmin) to say that it easily beats D-RTK2. Yes, there are many advantages, but also disadvantages. The operation of the two systems is different. Here’s how:

Connection: The D-RTK2 directly connects with the drone. A loss of signal from the remote does not mean loss of fix. The connection is super robust with great range.
In the case of RS2, the connection is made through the remote control’s wi-fi. What really bothers here is the range. For the connection to be minimally stable, it must be literally side-by-side with the base. If you walk around to get a better look of the aircraft or even turn your back to the receiver, placing your body between the remote control and the base, it is possible that the connection will drop and you will lose the FIX.

Battery: You can’t compare the RS2’s autonomy with any other receiver on the market. That said, replacing the D-RTK2’s batteries is convenient enough. It comes with two batteries of the same type that you already use in the remote and can be easily charged using the BS-60 Charging Station.

Reliability: Here for me is the big advantage of using D-RTK2. For over a year I used D-RTK2 without ever having to change its settings. There was never any convergence or connection error. Just turn on the device and everything is working. RS2 had convergence problems on 2 of the 3 first days that I looked it to the field. This is a big hassle, because when you don’t get a fix, there’s not much you can do other than reboot the whole system, which takes time and generates frustration, especially if you have large areas to cover.

In short. I consider the RS2 to be a super versatile and cost-effective solution that gets the job done. Especially if you don’t already own a GNSS pair, or if, better yet, you already have an RS2. On the other hand, if you already have an RTK pair and need a dedicated receiver just for your aerial application, I would consider D-RTK2 for sure. I would also recommend D-RTK2 if you fly with third part payloads that require extra time to warm-up/shut-down as LiDAR sensors, for example, were having to restart the whole system might be too much of a pain.

I’ve lost corrections allot more times over Lora than a direct local WiFi connection. If you’re only using it as a local base then the D-RTK 2 will do what most people need but just the fact that it allows for Lora corrections doesn’t make up for it’s inconsistencies in observations, poor battery and having to use the RC as a data collector. Don’t even get me started on the dongle. Why would anyone want to deal with this when you can just buy the aircraft by itself and for $500 more have a fully functional surveying system? From an AEC and Surveyors point of view the RS2 easily beats the D-RTK 2.

1 Like

Hi Tiago,

Thanks for sharing your thoughts!

If you notice any issues with getting a Fix solution or connection stability, please write us here or via support@emlid.com. We’ll look into it and figure out what’s wrong. In most cases, it’s something related to the setup. So, we can solve it remotely.

This topic was automatically closed 100 days after the last reply. New replies are no longer allowed.