What You See is What You Measure in Mobile GIS – Part 1, Data Capture
Posted on Fri, Apr 29, 2011
We talk about the advantages of an all-in-one mobile GIS solution, show you the ikeGPS device and report results from real case studies. But it may not be so clear how easy it is to use ikeGPS to capture remote data and measure positions, distances and offsets.
The name of the game is establishing your position accurately via high accuracy GPS, viewing and measuring the distance and bearing from your position to a remote object using laser ranging and a 3D compass, and capturing a photo of the object and storing the data for further use in GIS applications. ikeGPS then saves this information as a TrueSize photo. This is where the magic happens. Using a variety of applications, we can then select and measure the heights and dimensions of any object within the image. A classic use case would be a utility pole audit - measuring a large number of poles and recording the heights and positions of various attachments.
The first step is accurately capturing the pole location. In the image to the right you see the onboard data capture application “ikeCapture” in use on a utility pole.
Crosshair: Aim the crosshair at the target pole.
Distance: Laser range from the target position.
Compass: Bearing in degrees from North (T = True North, M = Magnetic North).
Zoom Slider: For closer targeting.
PDOP: A measure of GPS accuracy. The lower the PDOP the better the GPS accuracy.
GPS Fix*: Shows the type of fix - 2D, 3D, or DGPS (WAAS).
Skyplot: Shows GPS satellites in view and in use.
Capture: Press to capture targeted position data and a photo image, which gets stored for further use.
Menu: Access to ikeCapture Settings or Exit
* With 'High Accuracy GPS Option' installed the GPS Fix will show as 2D+, 3D+, or DGPS+
NEXT POST: What You See is What You Measure in Mobile GIS – Part 2, Measurement