Horizontal scale calibration of theodolites and total station using a gauge index table

[摘要] This paper shows a methodology to calibrate the horizontal scale of theodolites and total station using a high accuracy index table. The calibration pursued the method of circular scales and precision polygons (also called Rosette Method [1] or multistep). This method consists in the angle comparison of two circular divisions in all relative positions possibilities. Index table errors and theodolite horizontal scale errors were obtained using the method of least squares which is used to process the data from Rosette Method. An experimental setup was used to evaluate this methodology and the details of the mechanical assembly are also described in this paper. Several theodolites and total stations were calibrated using the proposed system and the results infer that the method is suitable to calibrate the different models available in the market. The system showed good stability over time with measurements uncertainties around 1' (one second) depending on instrument features.

[发布机构] Dimensional Metrology Laboratory (Lamed), Mechanical Metrology Division (Dimec), Direct. of Scientific and Industrial Metrology(Dimci), National Institute of Metrology, Quality and Technology (Inmetro), Av. Nossa Senhora das Graças, 50, Duque de Caxias, Xerém, RJ; 25250-020, Brazil^1

[效力级别] 力学 [学科分类] 力学，机械学

[关键词] Good stability;High-accuracy;Mechanical assembly;Method of least squares;Relative positions;Scale calibration;Scale errors;Total station