January 24, 2019, 12:29pm
I recently experienced something strange with Reach RS+. I’ ve made a stake out and have surveyed each point. The results were surprising because since point sovit11 elevations were rising and they should be decreasing.
i have finished surveying the street and it crosses with recently surveyed street and elevations differ with about 80 cm.
The elevations in second pictures are transformed with a licensed program from ellipsoidal to Baltic height system, and they also differ in ellipsoidal height.
January 24, 2019, 4:38pm
Yes, i am uploading all the ubx files for this date, i am not sure how to view them.
*. raw_201901230646_UBX.zip (8.0 MB)
raw_201901230744_UBX.zip (1.5 MB)
raw_201901230758_UBX.zip (726.2 KB)
raw_201901230807_UBX.zip (5.0 MB)
January 31, 2019, 12:41pm
Ill try take a look at the raw files later. Thanks for uploading.
January 31, 2019, 12:42pm
Can you also provide the survey csv file?
February 1, 2019, 6:09am
Yes, here it is:
NoviPazar-CSV.zip (2.7 KB)
You were measuring each point only for 3-5 seconds. I would suggest measuring it for longer time (at least 10 seconds). Points are measured in Novi Pazar, Bulgaria?
February 1, 2019, 2:06pm
With the right (optimal) conditions, you dont need more than 2-3 secs.
After some talks here on the forum, I decided to see how the relative precision of the Reach RS+ is.
I started by laying out and securing 40x30 cm GCP’s, and securing these with 2 spikes each to eliminate the risk of disturbing the point during repeated measurements.
Base setup on previously measured point on a tripod and tribrach. Rover on a pole, and stabilized with bipod. Measuring base and rover heights with a laser distance meter.
RTK-settings for Rover
We can try to post process your data, but I can’t find any RINEX data from Bulgaria. Maybe you know any NTRIP caster? Which one were you using?
February 1, 2019, 2:24pm
I was using 1Yocto network. The interesting thing is that all points are in straight line, meaning that X and Y are ok, even elevations collected by 2019-01-23 08:25:10 UTC are ok even with 2-3 sec. I have previous data collected by a surveying firm with gps, that matches elevations measured with emlid.
They have RINEX only for sale, unfortunately.
Can you share your RINEX base log here, please?
February 8, 2019, 2:36pm
I had the base corrections set for collecting RTCM data. I have attached them in case they can be in any use.
Can you share how to open these type of files? base_201901230646_RTCM3.zip (572.3 KB)
base_201901230807_RTCM3.zip (386.5 KB)
Do I understand right that you expect the height of the
soviet17 and so10 to be the same?
February 10, 2019, 3:57pm
Yes, it is one street, with 2% slope max, the difference should be about 6 cm. And i was on sight, there are no holes this deep.
February 10, 2019, 3:58pm
The problem with the height starts with point: sovit11, it should be lower then sovit10.
I can assume, that the issue is related to the following factors:
@jurijs.jeshkins mentioned, your point collecting time is a way to short. I’d recommend to increase it to a few minutes Also, your NTRIP station is quite far from the rover. The distance is around 20km, however, the recommended baseline is 8-10km
Another reason is that you’ve got strange signal breaks on base logs
Do you have any plans to do more tests?
February 14, 2019, 6:49am
Thanks for the help. I am using Reach Rs+ in my practice, and if i encounter something else which is strange, i will let you know. I have made an initial test when i bought Reach and compared points measured with Trimble R4 and Reach RS, and results were satisfying, but i was using a pole holder and were gathering observations for longer periods (couple of minutes).