2013 Kentucky GIS Pre-Conference Workshop

GPS Technology: Survey vs. Mapping

Mr. Jeff Clark, PLS -- Precision Products Geospatial Division

Mr. Eric Muncy – Precision Products Geospatial Division

Sputnik

Launched in 1957

First man made satellite

Transmitted radio signals

Lived for about 3 months

US Military

First used in the 1960s

To track nuclear power vehicles - ships

Korean Flight 007

Shot down September 1983

Accidently was in Russian Air Space

Presidential Order was signed to make GPS available for civilian use

Selective Availability (SA)

1989 – Intentional dithering of the satellite clocks by the DOD called SA was instituted in 1989.

2000 – President Clinton ordered SA to switched off on May 2, 2000.

Had little to no effect on surveying applications of GPS

Greatly improved consumer grade GPS

BASE STATION

Different Grades of GPS?

Consumer or Recreational grade…Consumer Grade

Inexpensive

15 to 30 feet accuracy

Good for general locations Navigation Street Signs Trees Buildings (911)

Mapping Grade…Mapping/GIS Grade

1 inch to 10 feet accuracy

Digital Clipboard

Good for more accurate locations Hydrants Manholes Roads

Survey Grade Centimeters accurate

Most robust

Good for the accurate locations related to: Control networks Land boundaries Topographic & Engineering

Surveys

What is the freaking difference??

Survey vs. Mapping

Collection of Attributes/Photos Taking GIS data out with you

Mapping - Software

Stakeout operations Volumetric calculations Coordinate Geometry Metadata - Datums, NAD 83, Geoids

Survey - Software

• VRS – Virtual Reference Station

• Free Service (Anyone to use)

• Can be used in real time (Cell phone / Cell modem) or back in the office to process GPS data

• Continuing to be improved (location and accuracy)

• http://kycors.ky.gov/

KYTC VRS - Basics

KYTC VRS – Basics

THEN

KYTC VRS – Basics

NOW

Questions?

Contact Info:

Mr. Jeff Clark, PLS Cell: 270-559-9097 Email: jeff_clark@yourprecision.com

Mr. Eric Muncy Cell: 859-321-3675 Email: eric_muncy@yourprecision.com