FASTSURVEY RTK VS FASTSURVEY DGPS
Posted By Chet Suitt on 3/9/2008 at 1:36 PM

1st- performed an rtk session in fast survey in the back yard. (not alot of workspace=short obervations distances between points).
2nd- then located the same points with fastsurvey in dgps mode w/internal antenna (hand held). reason for this test was to see if i could get sub-meter readings with hand held only for wetland flag locations or other objects located that only need sub-meter accuracy.
results--->

FASTSURVEY-RTK (FIXED)
POINT TO POINT AZIMUTH - DIST(FT)
CP-DOCK TO CP-STUMP 226-03-49 - 08.2728
CP-STUMP TO CP1-WEST 230-03-49 - 43.5201
CP1-WEST TO CP2-MID 070-51-49 - 35.6886
CP2-MID TO CP3-EAST 070-42-08 - 12.1220
CP3-EAST TO CP-DOCK 342-17-39 - 18.6753

FASTSURVEY-HANDELD (DGPS)
POINT TO POINT AZIMUTH - DIST(FT)
CP-DOCK TO CP-STUMP 217-44-21 - 08.7938
CP-STUMP TO CP1-WEST 230-09-29 - 43.5030
CP1-WEST TO CP2-MID 071-05-31 - 35.1587
CP2-MID TO CP3-EAST 070-37-49 - 12.4334
CP3-EAST TO CP-DOCK 342-10-53 - 20.2816
with hand held i only took one shot on cp-dock the last inverse is just that a inverse from last shot to first shot. maybe that is why it is the worst in distance?
results were better than anticipated. conclusion, more real world tests warranted, expect satisfactory results.
has anyone got similar, better or worse results?





Re: FASTSURVEY RTK VS FASTSURVEY DGPS
Posted By Stan Piper on 3/9/2008 at 1:49 PM

Shots taken only minutes apart in DGPS will have relative relationship better than 1 meter but their true world position is not good as there relative positions. For a good test use a OPUS solution for the RTK base shot the points with good positions the DGPS the points on different days and at different time of days (different sv constellation) compare these result to the position of the OPUS based RTK shots.


Re: FASTSURVEY RTK VS FASTSURVEY DGPS
Posted By Phil Stevenson on 3/10/2008 at 5:38 PM

A recent science project uses FAST Survey and SBAS together with Localization - Add Method 2 to stake out 21 points from two different static survey projects.

This was done with a ProMark3 and then done again with the MobileMapper CX.

The cut sheets from Carlson Survey are available on request.


The ProMark3 average of the 21 staked out points is North 0.27 feet and East 0.15 feet.

The MobileMapper CX average of the same 21 points is North 0.06 feet and West 0.54 feet.

Each of those points has some environmental challenge that complicates a GPS solution. These were not hand picked to make it look good. They are points where a GPS static survey project was possible.


Do you want to see a slide show of fire hydrant photo mapping?

http://www.kodakgallery.com/I.jsp?c=3htd6u50.6zjvzoa8&x=0&y=w6ap0x

Modified By Phil Stevenson on 3/14/2008 at 6:38 PM