Tools to help the armchair archeologist

A few weeks ago, we showed you a recent case of an “armchair archaeologist” who used Google Earth to discover almost 2,000 archaeological sites in Saudi Arabia.

With more and more stories like this popping up in the past few years, GEB reader “Will from the UK” has built a slick tool to help with the process.

In his words:

I enjoyed your post about the archaeologist who found interesting artifacts in Saudi Arabia using Google Earth. It got me thinking about how to do a systematic search of an area using GE.

There are no tools in GE that help, other than the usual lines / placemarks. Marking an area out using lines is fairly tedious. A grid is a useful solution. I have seen grid generators online, but they tend to come and go, and you need to be online to use them.

I have created a spreadsheet that generates the KML code for a Latitude / Longitude grid. A grid allows a more systematic search to be conducted and also allows more people to take part in a search – the work can be divided between many volunteer searchers.


The resulting spreadsheet is quite impressive, and it is a great way to divide up a large area for more precise searches.

You can download the Excel-based spreadsheet here. The spreadsheet is remarkably powerful, though it has a bit of a learning curve and a few limitations. Fortunately, Will has been generous enough to develop a User Guide (PDF) to help you get started.

New Free-Busy feed for the Google Calendar API

There is now a convenient way to query free-busy information from Google Calendar. The new Google Calendar free-busy feed allows you to query blocks of busy time for one or multiple users, or for all the users subscribed to a Google Group in a single request.

This new Google Data feed is accessible through the URL pattern
where “userID” is the email of the calendar you’d like to request the free-busy information of. The response will be an entry containing temporal blocks indicating the periods when the user is marked as busy in their Google Calendar. Visit our Developer’s Guide for more details and code samples about the free-busy feed.

You can also query free-busy information for multiple users in a single query using a batch request. The URL to use for such a batch request is:

Below is a sample batch request, requesting free-busy information for Liz, Bob and Luke:

This allows you, for example, to find common free time between multiple users in one single request to the Google Calendar API, which was not possible with previously existing feeds.

For example, the response from the batch request above would look like:  2010-03-13T00:00:00.000Z     … updated, category, self link, author and batch info ...                                            … Free-busy entry content for Bob ...    … Free-busy entry content for Luke ...

The response contains an entry for each requested calendar’s free-busy feed. Each of these entries contains blocks of time where the user is marked as busy in his Calendar for the next 24 hours.

Google Apps for Business domain users are also able to query free-busy information for all the members of a given Google Group in a single request. This feature is available through the following URL pattern: Where “groupID” is the email of the Google Group.

The response will be a feed containing the free-busy entries of each member of the group. To learn more about querying free-busy for groups please visit our Developer’s Guide.

Augmented Reality for SketchUp

The first time I saw Augmented Reality in action, I wondered if I’d accidentally fallen through a wormhole on the way to work; it’s the kind of thing you’d expect to see on Boba Fett’s BlackBerry. AR is downright futuristic.

In the 3D modeling sense, AR involves combining a live video stream with a 3D model to create the illusion that the model is a physical object in the real world. All you need is a webcam (the ones that are built in to many laptops work just fine), a 3D model (SketchUp takes care of that), a printed-out paper “target” and a piece of AR software that can put everything together. This video shows AR in action:

And here’s an illustration that shows the setup:

A simple Augmented Reality setup for SketchUp, using an external monitor to show the video output.

Thanks to an Italian outfit called Inglobe Technologies, SketchUp users have been able to ride the AR wave for a while now. They’ve just released version 2 of their AR-media Plugin for Google SketchUp. Three great things about this shiny, happy piece of tech:

  • It’s available for both Windows and Mac OSX.
  • It’s available in three flavors: Free (Personal Learning Edition), Professional Lite and Professional.
  • I was able to use it, which means that it can’t be that hard to figure out.

Start out by grabbing the Quick Start Guide; you’ll find the relevant links about halfway down the plugin’s webpage. Follow Steps 2 and 3 to download and install the software; the free Personal Learning Edition will let you see how everything works without spending any money. After that, achieve instant gratification (my favorite kind) by skipping ahead to Step 6 in the Quick Start Guide: “Creating your first Augmented Reality Scene”.