THE EFFECT OF SELECTED MATERIALS AND COLOURS ON THE PERFORMANCE AND RELIABILITY OF REFLECTORLESS TOTAL STATION

Abstract

Surveying equipment has metamorphosed severally in the last three decades due to technological advancements. Despite these technological advancements in equipment; the survey industry continues to struggle with the collection of data relating to inaccessible points. The introduction of reflector‐less total stations has made inaccessible points measurements possible with relative ease. These measurements are made possible by accurate observation of targeted points using laser or optical equipment. However, there are some questions as to the performance and reliability that can be achieved with such equipment. This research is to examine the effect of selected materials and colours on the performance and reliability of reflectorless total station, especially in relation to the quality of distance measurements. In order to achieve the objective of this research, pre-laboratory tests were carried out on nine different rock samples to determine their density, hardness, uniaxial compressive strength and petrologic characteristics (namely, the mineralogical composition, texture – size grains – structure – arrangement of the minerals and voids) and weathering state during samples preparation. The results show that the value of density ranges between 2.51 g/cm3 and 2.77 g/cm3; the rebound hardness value varies between 27.5 MPa and 51.0 MPa; the uniaxial compressive strength ranges between 46 MPa and 160 MPa; the mineral composition of the rock samples composed of felspars, plagioclase, quartz, orthoclase, calcite, dolomite and minor amounts of mafic minerals, such as biotite, hornblende. The main experiments were carried out using 25 different types of minerals and materials surfaces as targets. The experiments were evaluated by taking the horizontal distance measurements to reflector as ‘true value’ to check the reliability and performance of reflectorless measurements. The data acquired were subjected to correction as recommended by the manufacturer of the Total Station used in this research. The results show that all the readings fall within the upper and lower limits of the reflector readings. This shows that materials and colours have negligible effects on the performance of Reflector less Total Station.