Pocket PC GPS vs Trimble TCS1 Asset Surveyor

Fsman · 07-15-04, 05:06 AM

Is anyone familar with Trimble's TSC1 with Asset Surveyor? How does Pocket PC GPS stack up in capabilities with this older high end GPS system?

JakeRich · 07-15-04, 08:56 AM

In what way? Trimble's website didn't show the specs on the GPS receiver, but it talked about WAAS, which implies the same accuracy as any WAAS receiver. The functions of that surveyor system are dedicated to the asset inventory purpose, while most PPC GPS systems are oriented to road mapping or off-road trekking. You might look at some of the topo packages but don't expect any of them to have integrated asset inventory systems. If all you need is accurate GPS data, then any WAAS enabled GPS receiver and a PPC should work, and be a much smaller package!

DoDoubleGeo · 07-15-04, 01:40 PM

As far as I'm concerned you cannot even compare these two systems. The Asset Surveyor package runs around $5-10000 and uses a GPS reciever capable of decimeter accuracy(after post-processing). I'm not aware of any PPC receivers cabable of that level of accuracy. The name Asset Surveyor may be a bit misleading, it is not soley designed for asset inventory, but rather it's primary function is much broader; the automated collection and update of information related to geographic features. In other words, it is part of a GIS (Geographic Information System). It is capable of capturing point, line and polygon features and allows for post-processing of the data to improve postional accuracy.

Most of the GPS applications for PPC are for route guidance and navigation. ESRI has a mobile GIS application - ArcPad. This may be closest to the functionality of Asset Surveyor.

Fsman · 07-15-04, 06:29 PM

Thanks for the replies.
If I can live the accuracy of the Pocket PC GPS, will I have the integration with ArcGIS that the Trimble has? CanPocket PC GPS have data dictionaries and shapefiles with point, line and area features?

JakeRich · 07-15-04, 07:32 PM

If the accuracy of the Trimble is really decimeters, you will not be happy with the current crop of generally available CF cards for the Axim. If decimeter accuracy is required, and if you still want to use a PPC, you can look to Garmin/Magellan/others for a decimeter accurate GPS with a serial output and use the serial port on the Axim for inputs. There is a demo at the ArcPad site provided by DoDoubleGeo.

Fsman · 07-15-04, 09:29 PM

Thanks for the speedy reply.

I am a forester and we use the TSC1 to map timber stands. I live in West Virginia so the use of real-time differential correction is practically non-existent due to the mountainous topography. In fact we never use it. Also because of the mountains, the horizon is much steeper than in flat areas, therefore satellite reception is often less than optimal. But still, we are able to achieve fairly good accuracy, usually between 2-15 meters in the field. We are able to use this "raw" data for navigating and such.

For mapping purposes, we fine-tune this data during post processing on our PCs. At this time, we obtain base station information, which "corrects" the raw data. We usually end up with maps of accuracy less than 10 meters. On a 24,000 scale map is usually unnoticeable.

We could obtain better accuracy but at a cost of time. For sub-meter accuracy, we would have to wait long periods during the day for satellites to become arranged properly. If I were looking for a pot of gold hidden under a rock, it would be worth the wait, but for our purposes our set up works fine.

But....the price of the Pocket PC GPS is so much less. Could we get similar results with a Pocket PC GPS? Would it receive satellites as good as the Trimble unit? Can the Pocket PC unit collect data as shapefiles (point, lines, polygons) and can we give these files attributes? Could this data be integrated with ArcGIS?

Sorry for being so long winded and thanks for your interest.

DoDoubleGeo · 07-16-04, 08:42 AM

ArcPad is completely compatible with ArcGIS software. It uses ESRI's proprietary shapefile format to store the postional and attribute data of the features and supports JPEG, TIF and SID imagery (maybe others). There is a plug-in for ArcGIS that will allow you to setup your data for use in ArcPad. Yes you can capture point, line and polygon features and assign them features using forms (similar to the TSC1's use of data dictionaries).

The big lacking in this software is the ability to do complex editing of line and polygon features, such as splitting and combining. According to ESRI it is possible, they just didn't want to code it into the application. For this reason, I tend to use the mobile application more for marking-up the 'map' and then do the editing back on the desktop.