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ACCEPTANCE TESTS FOR THE MPS-2 
M.H. Elfick 
University of Newcastle 
Australia 
ABSTRACT 
Evaluating an analytical plotter requires tests at three basic levels. 
Functional tests to check performance of electronic components, dynamic 
tests to check for repeatability and absence of backlash in mechanical com- 
ponents, and operational tests to evaluate the overall performance. 
This paper describes the systems used on the MPS-2 and includes the 
generation and use of precise 'pseudo photographs' to check performance 
characteristics. The tests used on this instrument could be adapted as 
standard checks to evaluate any analytical plotter and provide a simple 
means to do comparative assessments. 
INTRODUCTION 
Testing procedures have been proposed by various authorities and in 
particular by members of Commission II of ISPRS. This paper discusses the 
problem as seen from the perspective of the instrument designer who is con- 
cerned that performance matches the design concepts. 
Every instrument is subject to compromises in the design phase, for 
example one may have to accept a lower maximum slew speed in order to reduce 
heat build up from power supplies, or accept a less than perfect optical 
system to make use of existing 'off the shelf' components. 
The aim of the designer is to develop a system to cater for the needs 
of a certain sector of the market, and provide a product which performs 
selected functions to a given precision with minimum effort by the user. 
The testing procedures are used in three areas: 
(i) To evaluate the design concepts. 
(ii) To rest instruments before they leave the manufacturer. 
(iii) To allow the customer to evaluate the instrument. 
Before discussing the test facilities it is necessary to briefly 
describe the MPS system, including the software and hardware components. 
DESIGN AIMS 
The MPS System has been designed as a low cost solution to the pro- 
cessing of photogrammetric data. The system comprises a stereodigitiser 
running under the control of its own microprocessors (the MPS), a personal 
computer and associated peripherals such as an x-y plotter, printer etc. 
Software is provided on the PC for orientation and capture of data, 
while the stereodigitizer performs its functions from programs stored in 
read only memory (ROM). 
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