In the first two parts of this series, I covered real-time GPS tracking in Google Earth using completely free solutions. These next two are free to download and use, but are donationware – if you wind up using them on a regular basis, the authors would appreciate a small donation to show your appreciation.
GooPs – Windows only; donationware.
No installation is required, but it would be a good idea to put it into its own folder, where it will also keep configuration data and the KML file that saves your position and track data. Start up the program, and this screen appears:
Checking the AutoTrack box makes GooPs change the Google Earth view to follow you as your position changes. The dropdown box allows you to choose another individual to track, if they have GooPs installed and you have access to their network link. AutoView lets GooPs change the direction of viewing as your direction changes, but you have no control over the amount of Rotate, Zoom or Tilt it uses in AutoView. Pause stops tracking, Save lets you save your track up to that point in time as a time-stamped KML file, and loads it into Google Earth; ClearTrack clears out the track that describes your previous movements.
Click on Options, and you get:
Here you can set your GPS COM port and speed, normally 4800 for NMEA. Checking the AutoConnect button lets GooPs connect automatically to your GPS when it starts up, or you can connect manually using the Connect button. PlayBack/Demo lets you play back a track, or set GooPs into a demo mode that shows multiple tracks in motion in the Portland, Oregon area. The Add/Update Vehicle section lets you set or update the tracking parameters for your vehicle, localhost Server/Host for your computer, or a network link for someone running GooPs on a different computer. Land/Sea pins your track to the ground, while Air gets the altitude of the track from your GPS (e.g. if you’re in a plane). Under Track Properties, checking SpeedTrack makes GooPs change the color of your track depending on how fast you’re traveling, and Extrude is useful primarily with “Air” tracking in that it extends the air track vertically down to the ground, creating a track “curtain”.
The rest is reasonably understandable, and that’s good because GooPs comes with no helpfile or documentation. There are a few other issues as well, like the inability to change the shape or size of the cursor that represents your position, though you can change its color. If you want to set your own zoom, tilt, or bearing, you should turn AutoTrack off, at least temporarily; you can change these parameters with AutoTrack on, but GooPs will “fight” you and keep you from adjusting them more than a certain amount with a single click. For example, you might zoom in a bit, then GooPs will stop you from zooming in any further, and you’ll have to click again on zoom to move in closer. And Google Earth did occasionally crash while I was testing GooPs. Still, it’s a pretty good program for real-time tracking in Google Earth.
Update (3/15/2007): You can now change the size of your cursor in GooPs, and AutoTrack no longer fights you when you try to change your viewing position. I’d now call GooPS and EarthBridge even, and since GooPs is still in active development, it’s likely to improve with time.
EarthBridge – Windows only; donationware
EarthBridge has a standard Windows installer that runs normally. You could also manually create a folder called “earthbridge” in the root of your C-drive, since EarthBridge will look for that folder as the default location to put the Google Earth network link, and save all of the current data in permanent form. EarthBridge can run minimized in the System Tray as an icon, a double-click or right-click bringing up the program window with multiple screens accessible via tabs.
Preferences lets you set GPS parameters, where data is stored, and start-up options like connecting automatically to the GPS when you start the program, or starting up Google Earth in tandem with EarthBridge:
The GPS Status screen is unique among all the free options presented so far; it shows a GPS satellite sky map, signal intensity bars, and a window where the raw NMEA strings received from the GPS are printed continuously:
KML Settings is the main screen for controlling the program:
Under Placemark Settings, the Placemark Title (text next to your position marker) and Show Speed (your current velocity) are good for all settings. Viewing Altitude, View Direction and Viewing Angle are only operational when the “Fly To Placemark On Update” box at the bottom is checked. When that box is checked, the view in Google Earth will follow your position as it changes, and you can only modify the view parameters (angle, altitude, bearing) from within EarthBridge. When unchecked, the view will remain static while your marker moves within it, but you can change the view parameters using the normal controls in Google Earth.
Checking the “Use altitude data if available” will plot your position and track using the GPS altitude, but this usually only makes sense if you’re in an airplane. GPS altitude usually has significant errors associated with it, so you’re likely to see your track and position floating above the ground if you check this box; unchecking the box pins the track to the ground. Checking the “Change placemark icon while moving” box makes your position marker change from a push pin icon to a “car icon” when you’re in motion. It looks as though the author intended to add the ability to specify those icons, but currently that option is “ghosted” out.
The Track Settings and Network Link Settings sections is reasonably self-explanatory. The “Extrude the track …” and “Create a ground-based “shadow track” are only operational if you have the “Use altitude data …” box checked above. If you check the “Fly To Placemark …” box to have the Google Earth view follow you, you’ll have to click on the “Re-Load in Google Earth” button to enable it, and similarly if you uncheck it.
EarthBridge is the better of the two donationware options; it has more features, and is easier to use. Its main drawback compared to GooPs is that EarthBridge doesn’t seem to be in active development right now, since the last update was close to a year ago; GooPs appears to still be in active development.If enough people express an interest in EarthBridge by giving the developer a small donation, he might possibly become interested in resuming development on it again.
DestinSharks.com has also reviewed these two programs recently, and has a video showing them both in action.