This manuscript gives an overview of the multipoint method and the development of an easy to use measurement system which measures the deformation of large buildings. The multipoint method has previously been tested1, 2 and used mainly under controlled laboratory conditions (e.g. indoors). Difficulties are introduced when this method is used outdoors, mainly because of the increased measurement scale and the uncontrolled environment. Differences in air pressure due to convection or wind, as well as fog or rain can cause severe perturbations to the light which propagates towards the sensors. Compared with existing systems, such as laser trackers, our system does not need to scan the building, which leads to much higher temporal resolution, which in turn can be used to achieve a reduced statistical measurement uncertainty (averaging in time).
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