GPS Survey Equipment GPS Trimble R6 or R8 Legs+Bipod Controller* Base Station or VRS Competencies #1-5

GPS Survey Equipment GPS Equipment Basics In every office? Requires only 1 person Controller Setup Datums Anyone can get GPS buttons to work, we want QUALITY DATA! Competencies #1-5

GPS Survey Equipment

Competencies #1 How GPS works with satellites

Position Dilution of Precision (PDOP)

Sources of Error

GPS Survey Equipment Satellites send timestamp signals to Earth 3 satellites required for horizontal 4 satellites required for vertical 5 th is required for survey grade Competencies #1

GPS Survey Equipment Competencies #1 Why need phone?

GPS Survey Equipment Competencies #1 Rover plus base station Why need phone

GPS Survey Equipment Horizontal- Total Station accuracy about the same Vertical- Total Station generally more accurate Accuracy if not fixed Does not work properly without “sky” PDOP, Satellites Competencies #1

GPS Survey Equipment GPS Equipment Special Issues Site Calibration Once per Job Minimum # control points 2 big settings Observed Control Point Fast shot- Topo Can’t get close to building (15degree rule) Competencies #2