Android Applications forGNSS(RtkDroid and SW Maps)

Avinab Malla
avinabmalla@yahoo.com

Android Applications for GNSS
1. RtkDroid
2. SW Maps

RtkDroid• For RTK positioning using low-cost receivers.
• RtkDroid uses correction data from NTRIP casters (inRTCM3 format)• Uses RTKLIB 2.4.3b33 for RTK positioning.
• Corrected position output of RtkDroid can be used bySW Maps for data collection• Sets location of Android device using a mock location
provider so all other apps use RTK positioning• For installation files and more information, contact Dr.
Dinesh Manandhar at dinesh@iis.u-tokyo.ac.jp

RtkDroid

1. Select Connection Method(USB or Bluetooth)
2. Select Receiver
3. Select Format(ubx, sbf or rtcm3)
Use ubx for u-blox
4. Set Rover Mode
(Single, Kinematic or Static)
5. Set Ambiguity Resolution Mode
Continuous, Instantaneous or Fix and Hold
6. Set Antenna Height(From Ground to Antenna Reference Point)
7. Enter NTRIP settings(For RTK Correction)
8. Start RoverRecords solution as NMEA
and logs receiver raw data
inputPress this button tostart/stop recordingSW Maps• Free Android Application for collecting,presenting and sharing geographic
information• Can be used for large scale GNSSsurveys to collect detailed attributeinformation or just to display popularGIS data formats on Android• Downloaded more than 180,000 times
by users all over the world

Features• Collect data using internal and external GNSS receivers (Bluetooth or USB). Connect RTK
capable receivers for high accuracy surveying.
• Import and display popular GIS Data formats (GeoPackage, KML, Shapefiles, GeoJSON,MbTiles)• Google Maps or OpenStreetMap as background; Can also import and cache maps fromonline sources (WMS, XYZ Tiles)• Record tracks and photos.
• Export or share collected data directly to KMZ, Shapefiles, GeoPackage, GeoJSON andmany other formats.

Installation• Open Google Play Store• Search for SW Maps
• Install and open app• Allow permissions if requested(Android 6.0 and above)

App Navigation
Press to open Drawer(Or slide from left edge)
Change Background Map
Add Recorded or Drawn Feature Layers
Import External Layers (Mbtiles/KML/SHP..)
Add Layer Attributes

Create or Open Projects

Connect External Receivers(Bluetooth OR USB)
Record Features and Tracks

Display GPS/GNSS Data
(Position, Time, DOP…)Show Satellite Skyplot

Scroll Down for More

Take Geotagged Photos
Import Projects andTemplates from Device Storage
Upload Data to FTP Server
Share data to other users
Export to device storage
As KMZ, SHP, Excel…
Save and share layer definitions
as a template for other projects

SW Maps Folder
All exportedfiles saved here
Photos andVideos taken by
SW Maps
RAW GNSS Data
(UBX, SBF..)
Copy project
templates here

Copy GIS Data files(Mbtiles, KML, SHP, GeoJSON…)
to import here, inside format
specific sub-folders
Project files saved here

Exported KMZ in Google Earth
Drone Imagery Mbtiles

Shapefile Categorized Styling

Connecting u-blox External Receiver (SPP)• Connect u-blox receiver to phone USB port using OTG cable(You may also need to enable OTG Storage in some devices)• From Navigation drawer, select USB Serial GPS. List ofconnected devices will appear.
• Select u-blox GNSS receiver• Set Instrument Model to u-blox• Check Log to File
• Set Instrument Height• Press Connect

Connecting u-blox External Receiver (RTK)• RTK is supported with the u-blox M8P andF9P• Set Instrument Model to u-blox RTK andConnect• Open NTRIP Connection from thenavigation drawer• Enter NTRIP caster information and pressConnect.

Connecting Other GNSS Receivers• Instrument profiles are provided for many receivers• Profiles can be created for your receiver if you know the setup
commands.
• Alternatively, setup your receiver to output NMEA to serial port orBluetooth, and use Generic NMEA profile when connecting.

Using RtkDroid with SW Maps
• SW Maps (v2.4.1 and later) automatically uses RtkDroid positionoutput when RtkDroid is running.
• No configuration necessary

GNSS Data and Skyplot• Raw GNSS data files are saved in SW_Maps/RawFiles Folder

RTK in Android: Summary
For Data Collection with SW Maps:• u-blox M8T: Use RtkDroid for RTK, connects automatically with SW Maps
• u-blox M8P, F9P: Connect from SW Maps with u-blox RTK profile, thenset NTRIP Settings in SW Maps
• Other receivers: Use one of the built-in instrument profiles, or setup
receiver to output NMEA and use the Generic NMEA profile.
For Data Collection with Other Apps, set up RtkDroid as a Mock Location
Provider in Android Developer Options

Layers

1. Press to open Layer sidebar
Maximize/Close Sidebar
2. Change Background Layer

Toggle Track and Photo Point Layers
3. Press + to add layer

4. Select Layer Type(We will add a GPS RecordedFeature layer for recording
features using GNSS)

Add GPS/GNSS Recorded Feature Layer

Enter Layer Name
Geometry Type
(Point, Polyline or Polygon)
Change Map Symbol
Then Add Layer

Feature Attributes

125Also try adding a Photo Attribute34

Record Feature
Select LayerType in feature
remarks (if required)Enter Attribute Data
(Photos can only betaken after recordingthe feature)

Enable/Disable
Location Averaging

Record PointDrawing Features
1. Add a Drawn Feature Layer
Name: Area
Type: Polygon

Drawing Features

3. Feature
Name
4. Press to Add
2. AddFeature
1. Open
Draw Menu

6. Tap on
map to add
vertices

5. Press
Add Point
7. Press to CloseTap a feature point to open its properties.
You can edit attributes, delete vertices orget directions to a point using GoogleMaps.

Exporting Data

Things to Try• Record a Line Feature• Record a Polygon• Add an Options Attribute Field (Dropdown choices)• Edit attributes after saving feature (Hint: Tap the feature on map)
• Take a Photo Point (Select Photo from drawer)• Record a track• Export data to KMZ, copy to computer and open in Google Earth• Measure length and area by drawing lines and polygons

Templates• Projects once created can be exported as a template for otherprojects.
• Useful when many surveyors and instruments are deployed to collectthe same type of data
• Templates can be made on a Windows PC using the SW Maps
Template Builder tool, or exported from any existing project using SWMaps
http://swmaps.softwel.com.np/template_builder

Template Builder

SW Maps Applications

SW Maps used by IOM Bangladesh - Needs and Population MonitoringSW Maps Use for 2020 Census in Indonesia

SW Maps Training by Bhutan GIS SocietyConstruction Monitoring of Water Supply Works in Kathmandu Valley
http://wnms.softavi.com

SW MAPS used for Data Capture• SW MAPS was used for Survey ofcompleted and ongoing works• Web Based System with open source software• Uploading to server withphotographs• Web Interface for Data Query and Geometry Editing• Centralized PostgreSQL Database• Details of Construction Progress• Map Overlay

Sewerage Network Asset Condition Assessment and GIS Survey
http://sams.softavi.com

Sewer Asset Management System• Web Based Systemwith open source
software• Centralized Database• Web Interface for Data
Query and Editing

Total Covered=117 SqKm
Total Manhole Surveyed: 52,566
Sewer Line: 1,201 Km• Sewer Profile andManhole Details

SW MAPS used for Data Capture• Map Overlay
Application• Sewer Maintenance Management• Public portal for sewer maintenancerequest• Customized SW MAPS system for tablet
for onsite data entry and photographs• Automated uploading to server withphotographs• Automated Server Data Update• Asset Management
Survey using RTK GPS• Sewer network expansion

Community Water Supply Information
http://careims.softwel.com.np

Total Covered 5 Districts of Nepal

SW MAPS used for Data Capture• SW MAPS was used for Survey ofcompleted water supply works• Web Based System with open source
software• Survey of unserved Community andpotential water sources• Centralized PostgreSQL Database• Uploading to server with photographs• Web Interface for Data Query andGeometry Editing• Details of Water Supply Projects

Small Irrigation Project
http://sipnepal.org• Web Based System with
open source software• Centralized PostgreSQLDatabase• Web Interface for Data
Query and GeometryEditing• Irrigation Details

Total Covered = 9 Districts Total
Project Surveyed: 1200 (till now)

SW MAPS used for Data Capture• SW MAPS was used for Survey
works.
• Uploading to server with photographs• Editing of Geometries in Server• Map Overlay

More Information
SW Maps on the Google Play Storehttps://play.google.com/store/apps/details?id=np.com.softwel.swmaps
SW Maps Template Builder
http://swmaps.softwel.com.np/template_builder
SW Maps User Manual
http://swmaps.softwel.com.np/assets/resources/manual.pdf
RtkDroid Demo
https://www.youtube.com/watch?v=Z_C33io_8S4