The practice of surveying is continually changing in response to the availability of new technology. The use and application of four such technologies were investigated in this thesis: the Leica Disto Classic5 hand-held distance meter, Garmin eTrex Summit hand-held GPS, Polar s720i sports wristwatch and Compaq iPAQ PocketPC.
|Click on a picture for more information about that device|
|Leica Disto Classic5 distance meter||Garmin eTrex Summit handheld GPS||Polar s720i sports wristwatch||Compaq iPAQ H3800 Series PocketPC|
The technology applications explored included potential synergistic combinations of equipment such as the merger of Polar s720i and Garmin eTrex data, and the use of the iPAQ as off instrument data storage / backup for the Garmin eTrex and the Nikon NPL821 reflectorless electronic tacheometer. A brief examination of other potential uses of the iPAQ in Geomatics was also undertaken. Finally the plausibility of undertaking common surveying tasks with the use of the Leica Disto Classic5 traversing, building location and identification surveys. Two field trials were performed and the pros and cons of the Leica Disto's use in these applications documented.
The attempts to get the Compaq iPAQ to work as a support device to the Nikon NPL821 and Garmin eTrex Summit have proven unfruitful. While it is not impossible for the iPAQ to act in this supporting role, both software and hardware impediments (such as incompatible interface connectors) prevent the simple interconnection and communication of the iPAQ with these other devices. Of the standalone uses of the iPAQ in surveying, the use of the iPAQ as a platform for mobile GIS software (e.g. ArcPad, PocketGIS) is its' strongest virtue. In general, using the CAD packages available for the iPAQ is ungainly (though this situation may improve with familiarity), as is taking field notes in some form of sketching application. Overall it is the limited screen resolution and size of the iPAQ which restricts its' usefulness.
Logs recorded by the Garmin eTrex Summit and Polar s720i both include time, distance, velocity and altitude. Though somewhat processing intensive, integrating the data from these two devices allows a more accurate representation of a day's travel to be constructed than would have been possible using only one of these devices. For the bicycle tour data of 1 May 2003 used in this thesis (shown here before and after processing), the importance of instrument calibration and/or use of known reference points is underlined. Despite having two independent logs of altitude, there are large systematic observation errors which cannot be removed from the combined altitude profiles.
The use of the Leica Disto Classic5 in outdoor surveying is limited by two fundamental problems. The most insurmountable of these is the inability of the Disto's laser pointer to be seen in brightly illuminated situations. Additionally the Leica Disto Classic5 has problems with pointing stability when mounted via its mount point. When used with the custom mount built for this thesis, attempting to measure distances greater than 10 m proved unproductive, specifically as a result of these two problems. Even when mounted on a standard camera tripod, at ranges longer than 25 m pressing any buttons on the Disto causes its laser pointer to move so significantly that targeting becomes unreliable.
Despite these problems, when used in low light and/or confined conditions, the Disto does have its advantages. Paramount of these is the speed and ease in which the instrument can be used. Additionally, the Disto can remove the need for an assistant and enables otherwise unobtainable measurements to be acquired. Consequently, the worth of a Leica Disto is highly dependent on the nature of work performed.
For more information please contact the School of Surveying and Spatial Information Systems:
|Phone:||+61 2 9385 4182|
+61 2 9313 7493
|Mail:|| School of Surveying and Spatial Information Systems
University of New South Wales
Sydney NSW 2052