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Archive for the 'Google Maps' Category

Crowdsourcing And Coordinating Data Collection With Handheld GPS Units

Got an email today from someone with a data collection/coordination/assembly problem. They have multiple people out in the field with Garmin GPS units recording data, and bringing it back to a central location for collation/combination when they’re done. Since Garmin GPS units have limited capabilities for data storage – coordinates, name, comment, date and time, elevation, and that’s pretty much it – additional data associated with a point has to be recorded by hand. Once back from the field, data has to be downloaded from individual units, associated with the additional attribute data from forms, all the data combined together into a single dataset, then converted into GIS-friendly format. And the process they had come up with wasn’t really working well for them.

I think this highlights some of the major limitations of classic stand-alone handheld GPS units. They’re really designed for us in personal data collection, not combined data collection; assembling data from multiple units can take a lot of work. Plus, their limited data collection capabilities require offloading data attribute acquisition to other formats (e.g. pencil and paper), adding the addition problem of associating that data with coordinates later on. There are lots of professional solutions for these problems, like Trimble or MobileMapper GPS units, Terrasync and ArcPad software, but these can be complicated and expensive. I challenge you to find anyone with enough patience to use Terrasync for a single day without swearing at least once; I know I can’t  ;-).

For a few years, I’ve had CyberTracker on my list of potential topics to post on. CyberTracker is a terrific data acquisition and collation tool for field data with tons of great features, like custom data acquisition form design for easy data entry, moving maps, easy data collation and conversion to GIS-friendly format. Plus, the software is free, and the hardware is (relatively) affordable. But unfortunately, I think time and technology are passing Cybertracker by:

  • While the central data software runs on Windows, the field data collection software runs on old-school Palm OS and Windows Mobile. Palm OS is dead; Windows Mobile development has stopped with version 6.5, and only maintenance updates are scheduled. So the useful lifetime of any data collection system built around CyberTracker is limited. If you need a fast/cheap/short-term solution, CyberTracker is free for non-profit use, and you could probably pick up the hardware very cheaply on eBay. Long-term, I don’t see it having much of a future in its current form.
  • The data collation model is also becoming obsolete. With CyberTracker, you have to bring all the data units to a single data download/collation computer. While there are still places in the world where this might make sense, an increasingly-connected world means that data download/collation to the cloud instead of an individual computer makes more sense.

I’m really excited about the possibilities for crowdsourced geographic data collection and collation using portable devices running Android OS (yeah, iOS too). There are already several interesting apps for doing this, and I hope to cover some of those soon on my AndroGeoid website. And I suspect that the small number of apps that can currently do this will be quickly joined by far more apps, and far more capable apps, in the very near future. But that doesn’t help with my emailer’s current problem. I suspect there are many different ways you could do this, but here’s the first approach that came to me using all-free software and services.

1. Make sure that everyone on the project has a Google account (i.e. Gmail); completely free.

2. Have the project leader created a single main data spreadsheet on Google Docs, with all the desired data attributes (e.g. point name, coordinates, comments, additional data fields from the paper forms, etc.) and share a link to that spreadsheet with other project members so that they can edit it as well.

3. Project members can download data from their Garmin units using DNRGarmin, and then export the data from DNRGarmin in CSV format.

4. Load the data into the spreadsheet program of your choice, and add/edit data from data forms to make it conform to the data structure of the main Google Docs spreadsheet.

5. Copy the data cells in the spreadsheet program, and paste them into the main Google Docs spreadsheet. Note: Use Ctrl-C and Ctrl-V to copy and paste cells into Google Docs instead of using the Google Docs Edit menu to perform those operations, as the latter doesn’t seem to work for pasting data from different applications into Google Docs. You no longer have a single computer as a choke point for data entry; multiple people can add data to a spreadsheet at the same time, and Google Docs will coordinate data entry so that nothing is lost. And if you save the spreadsheet data from steps 3 and 4 as separate files, you’ll have backup copies of the original data as well.

For those who aren’t comfortable with working with spreadsheets, Google Docs lets you set up a “Form” to let anyone add data to a Google Docs spreadsheet directly; however, this increases the chances of coordinate data entry error.

6. Now that you have all the data centralized in Google Docs, you have lots of flexibility in how you can handle it:

  • Export the data in CSV format, and you can then import it into any GIS program that supports CSV data. If your GIS program doesn’t, use MapWindow to convert your CSV file into shapefile format first.
  • Unlike shapefile attribute tables, where adding/removing/re-ordering attribute data columns can be a pain, you can easily perform those operations in Google Docs and then re-export the data in CSV format.
  • Convert the data directly into a continuously-updated KML network link for display in Google Earth or Maps using Google’s Spreadsheet Mapper tool.
  • Use any of Google Docs built-in tools to analyze/plot/sort/visualize data, including their way-cool Fusion Tables.
  • And I’m sure there are more options I haven’t thought of.

Know an alternate approach? Have any additional ideas?  I welcome your links and suggestions in the Comments section below.




Draw And Edit Google Maps My Maps Layers With DRAWaMAP

Joining quikmaps and ScribbleMaps, DRAWaMAP lets you draw features in a Google Maps interface, and save them. Supported features include:

  • Lines
  • Markers
  • Polygons
  • Time polygons – you set a time and speed, and DRAWaMAP draws a polygon encompassing the walking distance around that point based on Google Maps data.
  • Map Density Quadtree – ? Not sure, but it seems to create an editable polygon feature based around a starting and ending point.
  • Adjustable fill color / feature opacity.

Data import/export/editing features are very limited compared to quikmaps and ScribbleMaps, but unlike those two, DRAWaMAP lets you import or export data directly from/to Google Maps MyMaps. The symbology/iconology used in DRAWaMAP is substantially different than that used in MyMaps, which takes some getting used to; controls are a bit cryptic as well:

drawamapcontrols

There’s a help button that brings up short, helpful video tutorials for some of these, but others will require experimentation to figure out. But to view these help videos, make sure you enable allow pop-ups from the DRAWaMAP site; otherwise you may wind up wasting time by pushing the help control buttons multiple times to no effect before figuring it out (like I did :).  As the videos demonstrate, this AJAX app’s interface is designed to make it usable on a mobile phone, making it a decent alternative to the main Google Maps MyMaps web-based editor on those devices.

Via GoogleMapsMania.




Multiple Coordinate Systems In Google Maps, Reverse Geocoding, And More With The Worldwide Coordinate Converter

Clement Ronzon emails about his new website, The Worldwide Coordinate Converter (TWCC for short). Drag the globe-shaped icon to the desired location in a Google Maps interface, and get a pop-up balloon with the geographic coordinates for that spot, elevation in meters, and the nearest reverse-geocoded address:

twccballoon

At right is a two-part coordinates box, with latitude/longitude/WGS84 always in the top part, and a user-selectable coordinate system at the bottom:

coordschooser

You can also enter coordinates into the appropriate boxes in either the top or bottom section, click Convert, and have them converted to the other coordinate system automatically (and plotted on the map).




Google Maps Adds Measuring Tool

The main Google Maps page now has a distance measuring tool. It’s not turned on by default, so you’ll have to click on the green beaker at upper right (the Google Labs symbol for experimental features):

beaker

Then enable the Distance Measurement Tool in the window that pops up:

dmt

A ruler icon will now appear in the lower-left of the maps; clicking on that will put you into measurement mode. Clicking on the map will now draw a line:

mapline

And the pane at left gives you the total distance (metric or English):

pane

The entire Labs section is worth a look, as it offers several other useful options (as well as some useless ones, like adding the “Beta” title back to Google Maps).

  • A “Drag N Zoom” button that lets you select an area to zoom to (finally!).
  • LatLng Tooltip brings a little pop-up window near your cursor that always displays the latitude/longitude.

fullscreenlatlong

LatLng Marker lets you right-click on a point, and place a marker there with latitude/longitude. You can select the coordinate text with your cursor, copy the coordinates directly off the marker, then paste them elsewhere to save them.

droppedmarker




Online Elevation Profiler

Krystian Pietruszka emails about his new Geocontext Profiler site, based on the new Google Maps API version 3. Place two markers on a Google Maps view by clicking, and get the elevation profile between them:

geocontext

geoprofile

You can add as many additional markers as you want in any direction; to fine-tune a marker position, just click and hold on it, and drag it to the desired spot. You have multiple options for the lines between points:

  • Direct – Straight line between points
  • Driving – Elevation along roads from point to point (like this preset example for Death Valley):

deathvalley

deathvalleyprofile

  • Bicycling/walking

Click on the Geolocation IP link at right to jump to your local area; click on the double-arrow icon in the upper right corner to go to full-screen-width for the app (and back again). You can also link to a profile, or embed it on your site:

Note: The “Import KML” link in the upper left of the map will let you load and display KML data on the map, but doesn’t create an elevation profile between points or along a line.




Export Google Maps MyMaps Data As KML

Google Maps MyMaps feature lets you create and save simple maps (lines and points), and share them with the world. But the sharing is done through a network link, not through a stand-alone KML file, and you can’t save the data directly to your computer. The GMaps tips website offers a simple way to save a stand-alone KML file of your MyMaps map:

1. Create the map.

2. Right-click on the “View In Google Earth” link, and copy the link address; paste it into a text editor:

http://maps.google.com/maps/ms?ie=UTF8&hl=en&vps=1&jsv=206b&msa=0&output=nl&msid=106563725672137103118.00047ef5a12bca4f8b665

3. Change “output=nl” to “output=kml”

http://maps.google.com/maps/ms?ie=UTF8&hl=en&vps=1&jsv=206b&msa=0&output=kml&msid=106563725672137103118.00047ef5a12bca4f8b665

4. Paste the modified link address into your browser’s address bar, and go to it; depending on how your browser preferences are set, you’ll either save the KML file for your map to your standard download directory, or it will open in Google Earth. In the latter case, right-click on the KML entry in the View pane at left, select “Save As”, and choose a name and location to save it in.

Useful if you’re stuck using Google  MyMaps, maybe because of its collaboration options. If you don’t need to collaborate,  Scribblemaps and Scribblemaps Pro offer direct KML export and have a much greater selection of drawing tools than Google MyMaps.




ScribbleMaps Goes Pro

Posted a few months ago about ScribbleMaps, a very cool web app that let you draw shapes and symbols freely in a Google Maps interface, then save the map in multiple formats:

  • JPEG
  • Print directly from browser
  • Embeddable widget (no Google Maps API key required
  • Facebook map
  • Regular Google Maps view
  • Google Earth plugin (though this didn’t work for me)
  • KML file (for viewing in Google Earth)
  • GPX (for export to your GPS)

ScribbleMaps has just added a Pro version, still in beta, that adds a host of new features:

  • You can now set up an account to save and manage maps
  • Import data in shapefile, CSV, tab-delimited, Excel spreadsheet, KML
  • Custom line styling
  • Larger color palette
  • New marker icons
  • Data layers, with full management
  • Line and polygon measurement tools
  • Object rotation tool
  • Undo/Redo
  • KML editor
  • Multiple language support

A cool tool that just got even cooler. Free for now; no mention of future cost that I could find, and I hope it stays that way.




New At HeyWhatsThat: Solar Eclipse Simulator, WebApp For iPhone And Android

I first posted about HeyWhatsThat 2+ years ago; its initial functions included:

  • A panorama of what’s visible from that location, marking the position of peak geographic landmarks
  • A list of the peaks, and the ability to show their position relative to your location on Google Maps
  • Terrain profiles (elevation versus distance from the location to any point on the map).
  • A plot all the areas visible from that location in red on Google Maps (aka the “viewshed” or “weapons fan”).
  • Contour lines.
  • Google Earth export of position, viewshed, horizon line and horizon extent.
  • Mike Kosowsky has been adding functions to HeyWhatsThat since then, and writes to announce two more:

    1. A simulator of Friday’s annular solar eclipse:

    eclipse

    2.  A web app to let you find out what you’re looking at using your iPhone or Android; point your phone’s browser to m.heywt.com.