Best field practices for GIS Data collection: Presented by, Jacob Wittenberg Frontier Precision, Inc.

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2 Best field practices for GIS Data collection: Presented by, Jacob Wittenberg Frontier Precision, Inc.

3 Agenda What is GNSS Code and Carrier Data H-Star Processing Best Practices Code and Carrier Solutions Floodlight technology Real-Time Corrections

4 GNSS and GPS Acronyms GNSS Global Navigation Satellite System generic term for all satellite navigation systems GPS Global Positioning System (US Dept of Defense) GLONASS GLObal NAvigation Satellite System (Russian System) GNSS and GPS Fundamentals Copyright 2012, Trimble Navigation Limited

5 What is GNSS? GNSS Satellites Launched between 1997 to 2012

6 How it all works measure time difference between same part of code From Satellite From Receiver Distance D = Speed of light Time

7 Code VS Carrier L1 Wavelength = 19 cm L2 Wavelength = 24 cm Carrier Code

8 Code VS Carrier Generalized Accuracy 10 meters to Submeter 1 CM to 30 CM Code Carrier

9 Code VS Carrier Vertical Accuracy Code Phase: - Can be 2 to 3 times worse than horizontal accuracy Carrier: Can be equal (for Decimeter) or up to 1.5 times horizontal accuracy

10 Best Practices 1. Non H-Star Best Practices Sirf Based XT or Submeter Based 2. H-Star Processing Altitude Constrained Positioning

11 No H-Star Processing R1 Receiver 50CM Juno 3 1-5m Nomad 1-5m Geo 7X -50CM Pro6T Receiver 50CM Yuma2 1-5M Juno 5 1-5M Enhanced GPS Available Enhanced GPS Available

12 Best Practices SiRF/Ublox Data Collection Best Practices Collect 5-10 good GPS Positions at each Point or Line Vertex Wait 10 seconds before logging GPS features after you arrive at the Point feature or Line Vertex. Real-Time Juno 3 Series 2-5m Juno 5 Series 2-5m Yuma2 2-5m Nomad 2-5m Juno5 and Yuma2 Enhanced 1-2m

13 Best Practices SiRF/Ublox Data Collection Best Practices Keep GPS antenna correctly oriented to sky? I say this but it s not really all that important The Juno will probably work OK in your pocket or on the dash of the car Real-Time Juno 3 Series 2-5m Juno 5 Series 2-5m Yuma2 2-5m Nomad 2-5m Juno5 and Yuma2 Enhanced 1-2m

14 Best Practices Geo7X (submeter) and XT Data Collection Best Practices More Positions are better. In most cases positions depending upon environment. No need wait to collect positions. Start Collecting immediately when you get to the position.

15 Geo 7X (Submeter) and XT-Level Data Collection Best Practices Avoid blocking satellites Use an external antenna in tough environments Larger groundplane Better components Easier to get above your body Best Practices

16 H-Star Solutions ProXRT 10 CM Accuracy Pro6H 10 CM Accuracy Code and Carrier Solutions GeoXH 7X /6000 XH Centimeter and 10 CM Accuracy (pending upon options)

17 Best Practices H-Star data collection best practices Avoid blocking satellites The receivers are very sensitive and can lose Carrier lock particularly easy The longer you can hold the carrier lock the better your positions will be Use the external antenna in tough environments Larger groundplane Better components Easier to get above your body

18 Floodlight Technology Built upon 3 technologies Multi-Constellation Capability Altitude Constrained Positioning Advanced Algorithms for Computing your solution

19 Floodlight Technology

20 Preferably start in a good environment with at minimum 5 SV s 2 minutes of carrier lock before collecting any data into your file. 2 minutes of carrier lock before you close out of the file. Altitude Constrained Positioning SBAS Best Practices Floodlight Technology Barometer needs to at ambient outside temp Not like a traditional barometer that needs calibration If SBAS is On the Sky Plot doesn t show GLONASS but it is being logged and used later when post-processing

21 Best Practices For all Receivers

22 Best Practices Avoid blocking satellites: Orientate the internal antenna correctly Put your body between any potential multipath sources Use a range pole and an external antenna to get the antenna above your body (high accuracy receivers) Avoid harsh GPS environments when collecting Carrier data Use the planning tools built into you collections TerraSync, GPScorrect and Positions. (Also available on your computer.)

23 Best Practices Position the antenna appropriately over the target: Set the correct antenna height if there is an offset. Hold the antenna directly over the target feature. Use a range pole for accurate vertical measurements (GeoExplorer or ProXT/ProXH series).

24 Best Practices Collect positions for a minimum of 5-10 seconds at each point feature or vertex within a feature. Increases the chance canceling out multipath errors. If the PPA or CEA is poor, you may need to log for longer (e.g. 30 seconds or more if accuracy estimate is not good enough and is improving). Note - Use a 1 second logging rate

25 Best Practices Collect good GPS measurements between features Post-processing will use all the information before and after a feature Whenever possible collect 30 to 60 seconds of good data before and after the tough feature.

26 Post-Processing Choose a base provider based upon: Shortest Distance from where you collected data Capabilities of base ensure the base tracks the same frequencies and constellations Reference frame of the base provider ITRF, NAD83 etc. Don t worry about the integrity index

27 Post-Processing Base Provider Reference Position

28 What Real-Time sources are Available? WAAS OMNI-Star Single Base Real-Time VRS

29 WAAS or Integrated SBAS <1 5 m <1 5 m Compatible with all current Receivers from Trimble and Spectra Precision FREE No Subscription Required

30 Trimble RTX Positioning Services m m Subscription Based - Pricing Varies upon Service

31 Single Base Corrections m m IP Based Radio Based

32 VRS - Virtual Reference Station m m Pricing Varies Per network Some are Free!

33 What Real-Time sources are Available? Mncors VRS Network

34 VRS Networks Currently Available in: Map denotes multiple available networks.

35 Vertical Accuracy HAE VS MSL (you need to know which to know which one) If you are referencing MSL: Software solutions come preloaded with a DMA10x10 (pending upon software) What Geoid Model are you referencing? Geoid 03, 09 12A..etc? Use a range pole Enter receiver offset from ground

36 Questions?

37 Jacob Wittenberg Frontier Precision, Inc. Support website:

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39 Trimble Geo7x Laser Rangefinder Dylan Jones

40 Laser beam Flightwave Technology

41 Overview 1. Hardware 2. Sensor & Laser Calibrations 3. Example Applications 4. Workflows Rangefinder Utility

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45 Ensures sensors are outputting the most accurate possible data for the given environment Sensor accuracy may be affected by: Environmental temperature fluctuations Device internal temperature changes Local magnetic conditions and disturbances

46 Fast Sensor Calibration vs. Full Sensor Calibration

47 Change job site After battery swap Sensor outputs are erroneous

48 First time the device is used Dramatic temperature changes Whenever the calibration utility recommends it Fast calibration doesn t fix erroneous measurements

49 Outdoors Only! Wide Open Areas!

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69 Laser Rangefinder Module Passive Range Reflective Range +/-0.05m Up to 120m Up to 200m Offset Positional Accuracy =

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