The INDOT CORS Indiana GIS Conference

February 19, 2008

By William A. Schmidt, PE, LS

Manager of Aerial Engineering, INDOTThomas A. Mahon, PE, LS

Survey Group Manager, Woolpert Inc

What is a CORS?

• Continuously Operating Reference Station

• Operated by Others

• Operates continuously

• Data available for Post-Processing

• Data may be available in real-time

Advantages of a CORS

• Single coordinate system

• Uniform precision

• No need to setup base stations

• Avoids base station radio issues

• Frees up base stations as rovers

• Increases productivity

• Ease of use

Existing CORSNGS

Existing CORS (cont’d)Seiler Instruments (01/15/08)

INDOT’s Primary Network17 New Stations

Typical Installation

• Add state map showing INDOT facilities

• Add picture of a maintenance yard

Primary Monumentation

Primary Monumentation (Cont’d)

Primary Monumentation (Cont’d)

Primary Monumentation (cont’d)

Secondary Monumentation

Station Locations

• Primary Station Locations– Indiana Department of

Transportation Facilities– Other State Facilities

• Secondary Station Locations– Other State Facilities– Higher Education (Possibly)– Private Consultants (Unlikely)

Network Administration

• INDOT Funded Primary Network and it is under construction

• Indiana Office of Technology (IOT) to Maintain Servers

• Servers dedicated to INDOT CORS

• Network Operations and Maintenance by INDOT Aerial Engineering (John Kurtz, LS)

Budgets

• Initial Capital Costs– Primary Network: $400,000– Secondary Network: $700,000

• Annual Operating Budget: to be determined– Hardware and Software Upgrades– Additional User Licenses (no charge)– Network Administration (IOT fees)

Schedule

• Procurement Bids – March 2007• Bids Received – April 2007• Bid Awarded – April 2007• Begin Primary Installations – November 2007• Complete Primary Installation, including

operational network – Anticipated Summer of 2008

• Begin Secondary Installation – Anticipated Spring 2008

• Complete Secondary Installation – Projected by the end of 2008

CORS Access

• Post-Processing– Free & Available from a web location to be

determined

• Real-Time Kinematic– Controlled by user name and password– Up to 300 concurrent users w/o paying for

additional access licenses– May develop a fee-based system of

access to support maintenance, upgrades, and IOT fees

CORS Access (Cont’d)

• Real-Time Differential– Coast Guard Beacons (10 m h

68%)– WAAS FAA (7 m h&v 95%)– Third Party Vendors Omnistar

(submeter 95%)– INDOT CORS (subdecimeter 95%)– Potential fee schedule similar to

RTK

CORS Challenge

• Real Time RTK – Vertical– Hundredths vs. Tenths

CORS Challenge (Cont’d)

• Solution to the Vertical– Height Modernization

• Better Geoid Model Development• Densification of Benchmarks

throughout Indiana• Elevations on existing HARN

Monuments• Elevations on CORS Stations• More Gravity Readings

INDOT CORS

• Questions?