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LOW COST IMAGE MAPPING FOR GIS
USING A REMOTELY CONTROLLED MODEL AEROPLANE
Bruce Chapman and Kevin Jones
School of Planning, Landscape Architecture and Surveying
Queensland University of Technology
BRISBANE QUEENSLAND 4000
AUSTRALIA
Commission IV, Working Group 1
KEY WORDS: Mapping, Orthoimage, Video, Acquisition, Video Image Mapping, Video Orthoimage,
Small Format Mapping.
ABSTRACT: Mapping from small scale remotely piloted vehicles (RPVs) is not a new concept. The idea is
so appealing in terms of its apparent simplicity and cost effectiveness, that numerous attempts have been
made with varying degrees of success. However, to date, a commercially viable solution seems to have eluded
us. It is true that military and police operations are carried out using RPVs but the criteria for mapping
purposes differs somewhat from those used for surveillance operations.
This paper discusses an experiment in which an attempt was made to circumvent the stability problems
associated with small RPVs by using a continuous imaging device (a video camera) which would enable a
subsequent selection of suitable images (frames) regardless of the turbulence encountered during the flight.
It was anticipated that some of these images may be geometrically marginal and only suitable for processing
using digital photogrammetric techniques. This technology now exists on personal computer platforms which
leads us to believe that the commercial viability of mapping limited areas using small scale RPVs will soon
become a reality.
2. PLATFORM STABILITY
1. INTRODUCTION
Small platforms are very prone to weather conditions,
From time to time, an idea or concept emerges and particularly wind. Gusty conditions play havoc with
disappears only to resurface at a later date. This may the attitude of the aircraft causing high angles of tip
be due to the fact that problems which are difficult to ~~ and tilt and rotation.
solve, render the idea inoperable for the technology
of the time. Line of sight control from an operator on the ground
is very difficult because at altitudes even as low as
As technology advances, some of the previous 300ft, the airborne unit becomes difficult to see
difficulties are easily overcome and the opportunity clearly and therefore to correct for change in position
for a new approach presents itself. and attitude.
We think that technology has now advanced to the
stage where it is worth revisiting an old idea i.e. 3. PLATFORM POSITIONING
aerial photography from miniature airborne platforms.
The simple RC (Radio Controlled) platform has line
This paper looks at the possibility of harnessing, ina — of sight communications. Lose the communication
cost effective manner, existing products to develop a and you lose aircraft and payload. Positioning is a
working system of data acquisition. This method matter of skilful judgment by the ground pilot and is
would have numerous applications for a myriad of consequently subject to gross errors. Altitude
surveying related tasks and if successful, could estimation is equally difficult so that the XYZ
considerably reduce the cost of data acquisition. coordinates of the camera station have a low level of
reliability.
Military and police surveilance operations have
driven the development of GPS, avionics and Usual aerial mapping techniques involve an aircraft
telemetric systems to an operational level. It would flying at constant elevation on a series of parallel
seem that an adaption of these systems for mapping 'runs' taking a series of still photographs with typical
purposes would be relatively straight forward. Let us forward overlap of 60% and side lap of 25%.
examine the problems associated with miniature
airborne platforms. To achieve this with a miniature platform would
require a complete solution to the stability and
159
International Archives of Photogrammetry and Remote Sensing. Vol. XXXI, Part B4. Vienna 1996
