Post processing - Reach or Navio?

Reach Module / M+ / M2 RTK / PPK configuration
1

Hi,
I would like to log high precision GPS data, but I don’t have a need for real time RTK. My use case is to log data during marine survey, and I would then like to post-process this logged data in RTKLIB, using either my own base-station data or publicly available correction data. I also want to log attitude data - and ideally would be able to combine attitude data with corrected GPS data to give precise vessel location and attitude at any given time. This data will then be synchronised with sonar data to create high-precision sonar mosaics.
My questions are: is the Reach module suitable for this? If so, how would the data be logged? (RasPi, mobile phone via bluetooth?). What format can raw GNSS data be logged in, and at what frequency? Are there any sensor fusion algorithms onboard?
I realise there are other options out there for logging raw GNSS data, but the Reach seems like a nice “all in one” module.
thanks,
Matt

2

Hi Matt,

The task you’re describing is one of the tasks that Reach was made for.
Attitude data logging is a work in progress, should be released after we finish a couple of other features.
Reach can log raw GNSS data on its own without the need of external devices. The format is UBX which can then be converted to RINEX. Also, very soon we will release an update where you can download RINEX from Reach directly.
GPS only frequency is up to 14 Hz, GPS+GLONASS or GPS+BEIDOU is 5 Hz.

3

Thanks Mikhail, that sounds perfect - I will make the order!

The really crucial thing for us (in addition to raw GPS) would be logging of compass headings, with other attitudes such as pitch & roll also useful (but not as important). Do you have any idea of time scales for this?

Also I couldn’t find any specs for the Reach storage space. Is there an SD card slot? If not, how long can raw GPS & attitude (when available) be logged for?

Also looking forward to some off-the-shelf case & PSU solutions!
thanks,
Matt

4

Very rough estimate would be 2 months.
There’s no SD, but Reach has plenty of onboard storage.
On 10Hz you would probably be able to log raw GNSS data and attitude on 10Hz for ~30-40 hours.
Reach was designed with integration goals in mind, so it comes without a case but in a protective heatsink.
Any 5V 1A PSU (even the mobile chargers) would be fine.

2 Likes
5

Thanks Mikhail - sounds absolutely perfect for my needs.