PlsSurveying—
Do you only take 1 actual shot on the point for X amount of seconds (Consecutive Samples)? If so I would recommend you to start taking 2, re-initialize your rover before taking the second shot (If there isn’t a function to do this in the app just dump the head to force it to lose its fix with the satellites). Stake out the point or if you can’t do that just call it a new store number like CK1 and compare the coordinates visually. A good rule of thumb though is if it took that long (10 Minutes) to initialize its most definitely a poor triangulation. Bottom line is you can never fully trust GPS in obstructed areas not even the new Trimble R12. I was hoping to utilize this for some of the people at this company for simple data collection but it scares me to only be able to get a CSV file with only PNEZ containing no information for the raw data the time it was collected.
Also what was your PDOP at for the bad shots? How many satellites were acquired during the occupation? Are you using a fixed height or a telescopic rod for the woods?
If you survey under a heavy canopy, there might be difficulties with getting Fix. The base and rover may not see enough common satellites, so that the rover wouldn’t be able to calculate its precise position. However, it’s quite strange that you see shifts when the receiver states Fix.
Let us investigate the issue further. It would be of help if you can share the following data:
a raw log from the rover
a raw log from the base or RTCM3 log
solution log from the rover
Also, please tell me the firmware version installed on your Reach RS2 receivers.
A second question regarding conversion of LLH base coordinates to NAD 83. (In the situations that merit it). If this cannot be done in the field due to lack of internet connection, how would you suggest I proceed?
If I get it right that you need relative accuracy only, you can average base position in Single in NAD83. You can do this in the ReachView 3 Base mode tab. After averaging, you will need to save coordinates to manual.
Those a great suggestions Alexi. Thank you. I did have another tough situation yesterday and got 2 separate fixes and a float solution on a point under winter canopy (mix of hardwoods and evergreens). One of the fixed solutions had 250 observation with standard deviations in northing and easting of less that .04 ft. The float solution was close (1.5 feet away) but the other fixed position (560 observations, < .12’ dev) was 8’ away from the first fixed position). So I will need to traverse in from a more open sky field close by.
I really like the idea of being able to stake out the point after collecting it.
As to your questions, I could not get that data from the CSV files. Hopefully I will learn how to get that info soon.
To get these logs, you will need to record them on the units during the survey. You can start and stop logging in the ReachView Logging tab.
Before you start logging, please turn on the Raw data debug option. You can enable it in the ReachView Settings tab. It allows us to get more data for investigation.
