Using GNSS Technology to Accurately Bring Field Information Into GIS. Daniel J. Yaw Jr.

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1 Using GNSS Technology to Accurately Bring Field Information Into GIS Daniel J. Yaw Jr.

2 About the Presenter Responsible for the upkeep and coordination of GIS and GNSS initiatives 550+ miles of active water main 80+ square mile of service area 33,000+ services 3,500+ fire hydrants 12,000+ valves LinkedIn.com/in/DanielYawJr Daniel J. Yaw Jr. Engineering and GIS Technician at North Penn Water Authority Medium size municipal public water system Located about 45 min. NE of Philadelphia, PA 8+ years experience working with GIS Bachelors in Management, Certificates in Construction Management and Drafting & Design

3 The Problem / Old GIS Update Process Field changes need to be brought into GIS Prior to 2014, we used only tabular field notes and sketches New roadways exported from CAD to GIS - Used to draw in assets

4 The Problem / Old GIS Update Process Hard to read Referenced measurements off locations (including roads) not on aerials Compounding errors Often missing measurements, wrong, or hard to read Roadways brought in from CAD never aligned correctly

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6 The Solution High accuracy MGIS grade GPS/GNSS technology Trimble GeoXH 6000 and Geo7X with Zephyr Model 2 w/ external antenna and VRS Tested on ten projects to confirm the process Used on every project since

7 What s GNSS? Global Navigation Satellite System All satellite positioning systems are a GNSS system Top two GNSS systems: - GPS (Global Positioning System): US owned GNSS - GLONASS (Global Navigational Satellite System): Russian owned GNSS How s GPS work? - Triangulation of position - Uses the time it takes for the radio signal to reach the receiver - Accounts for errors - The clocks need to be very accurate

8 What s VRS? Virtual Reference Station Accuracy level: total errors - Distance Errors - Multipath Errors Uses multiple reference stations Error computed on a computation server Computation server creates a VRS near your initial position Very high real time accuracy

9 Equipment GNSS Locating System Trimble Zephyr Model 2 Antenna - High accuracy - GPS, GLONASS Trimble GeoXH 6000 / Geo7X - High accuracy - GPS, GLONASS - Built in camera - Optional laser rangefinder (7X) 4G Wifi Hotspot - For real time VRS service

10 Equipment Protection Will be exposed to rough environmental conditions Most equipment will be weatherproof to an extent Protect your investment Make your own case

11 Out In the Field Done by inspectors Located as installed Process: 1. Drive to site 2. Assemble system, connect hotspot 3. Collects point at location Positions taken at point (can pause) Positions automatically combined Must be level and not move

12 Getting the Point Data Dictionaries - Attributes Form - Quick and easy - Always collect locater name - Hidden attributes - Date, time, static attributes (example unit type) Polylines: multiple Location Points

13 GNSS Locating in the Field

14 Back at the Office 1. Exported / formatted using Pathfinder Office 2. Rename / organize in ArcCatalog 3. Append to ArcGIS 4. Draw line features, rotate point features 5. Inspect locations 6. Inspect & modify attributes

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17 The Benefits Increased Productivity - Fast - Makes GIS data more valuable - Saves future time - Less errors 4 Accuracy! - Correct relevant to other assets - Data quality

18 Other Great Uses! Reverse locating - Navigate to a previously located asset GNSS Design Locating - We can use it to locate other infrastructure prior to design - Data exported to CAD.dwg Increase investment value

19 Training Your Staff (as Locators) Emphasize accuracy Write a manual Train personally Train in the field Have patience Takes practice Inspect work

20 Advice Won t make you a surveyor - Won t replace licensed professional surveyor Use as a definite location - Avoid manually moving Our assets don t need 4 accuracy, the assets themselves are bigger then that! - Correct position in relation to other assets Our aerials aren t even that accurate! - Do it right the first time - Everything else will catch up

21 If you do not know where you're going You might end up somewhere else -Toby Keith Don t let your assets end up somewhere else on your map!

22 Any Questions? Daniel J. Yaw Jr Engineering and GIS Technician North Penn Water Authority Lansdale, Pennsylvania LinkedIn.com/in/DanielYawJr