Long Distance Straightness Measurement Using a Level

Abstract

In order to obtain highly precision straightness measurement method, feasibility for method using a level was examined. The slope angle and straightness can be obtained with reproducibility of 10 micro-rad and 42 micro-m (sigma) by using sequential measurement interval of 1 to 2 m for 69 m of measurement distance. By using our error propagating model, shape reproducibility of better than 1 mm (2-sigma) was estimated for distance of 500 m and 10 km with sampling interval of 1.9 m and 20 cm, respectively.