Last week, I posted my feature “wish list” for a handheld GPS unit designed for advanced fieldwork by scientists, mappers, technicians, etc.. One step up from that “dream” GPS unit are the mini PDA-like GPS devices / handheld computers already on the market from companies like Trimble, Ashtech, Leica Geosystems and many others. These typically have somewhat larger display screens, usually touch-enabled, and often run Windows Mobile. These can be a good choice for field data acquisition, but also have some drawbacks:
- The screen size is fine for data acquisition, but can be too small for actual mapping work (both viewing and creating maps)
- Even the cheapest units will start at over $600; more expensive units can easily run into thousands of dollars
- The software for data acquisition and mapping is limited by the OS; there’s a lot less available for Windows Mobile than for standard versions of Windows (XP/Vista/7)
- Windows Mobile isn’t the greatest OS in the world, and development of it has been very slow
- The software that is available is often expensive
- Processor speeds tend to be slow
- Input is often by stylus only, which can be slow
- Storage space for datasets can be severely limited
One step up (or maybe sideways) from these PDA devices is the concept of a GeoPad, a field-capable full PC running a desktop operating system like Windows XP. I’ve been keeping my eye on these for a while now, as this isn’t a new concept. The University of Michigan’s GeoPad website talks about developing the concept since 2003; they define a GeoPad as:
a rugged Tablet PC equipped with wireless networking, a portable GPS receiver, digital camera, microphone-headset, voice-recognition software, GIS software, and supporting, digital, geo-referenced data-sets.
The advantages of a GeoPad over a PDA-based solution (which the GeoPad site calls a GeoPocket) include:
- Larger screen area, better suited for mapping, and easier for multiple people to view
- Full Windows OS, which opens access to all Windows-compatible applications
- Greater storage space (hard drive or SSD), for more datasets
- More input options: full keyboard, stylus, mouse/trackpad
But it has disadvantages compared to PDA-based solutions as well:
- Larger and heavier
- Shorter battery life
- Less rugged
But the biggest obstacle to GeoPad adoption might be cost. The GeoPad website lists a number of hardware/software combinations, with costs of about $4000-$5000; while the models are a bit out of data (circa 2007), costs of hardware and software comparable to the ones they list indicate that prices haven’t dropped as much as they have for other computer hardware.
About six months ago, I was asked to figure out whether it might be possible to find a combination of cheap hardware, and free/inexpensive GIS/GPS software, that would let you put together a GeoPad-type system for significantly less than the $4000-$5000 range without sacrificing too much in features. Over the next few months, I’ll be writing a series of posts on how I put together a usable GeoPad system for under $700 in hardware and software costs. It’s not a perfect system; I’ll point out where it’s deficient, and how to work around some of those deficiencies. But you’ll find some of those deficiencies on expensive systems as well. Overall, my cheap GeoPad does most of what the more expensive systems do, at less than a fifth the cost. And even if you don’t go the cheapest route, hopefully you’ll find some of my experiences useful in putting together a GeoPad system of your own.
PS If you have no interest in this topic, don’t worry; I won’t be focusing exclusively on this. Posts on standard blog topics will continue.