某地高精度室内真北方位基准建立方法

High Precision Indoor True-north Azimuth Reference Establishment Method

关键词:  几何量计量  真北方位基准  天文定向  寻北仪校准

Key words:  Geometric measurement  True north azimuth reference  Astronomical orientation  North-finder calibration

摘要:

为了校准寻北定向装备的寻北偏差，需要建立真北方位基准。由于气象因素的影响，室外真北基准目标成像质量和观测仪器稳定性均受到制约，因此，需要在室内建立高精度的真北方位基准。提出了一种高精度室内真北方位基准建立方法。本方法的真北基准采用2个平行光管和1个平面镜来维持，并利用2台Leica5100A 0.5″级电子经纬仪采用双测站天文定向方法进行标定。实测结果表明：2017年10月19和20日在室内外温差和湿度差很大的环境下，仅通过2个时段总共6个测回观测，计算得到的3个真北方位的平均值中误差分别高达0.17″、0.18″、0.20″。2018年10月11和12日进行了复测，3个真北方位的平均值中误差分别为0.47″、0.30″、0.48″，复测3个基准变化分别为+3.84″、+1.96″、+3.80″。测量结果表明，所建立的室内真北方位基准稳定，采用的技术措施和方法有效。

Abstract:

In order to calibrate the north-finder deviation of north-finder directional equipment, the true north azimuth reference needs to be established. Due to the influence of the meteorological factors, the outdoor true north benchmark target image quality and observation instrument stability are constrained, and it is necessary to establish high-precision true north azimuth reference indoors. In this paper, establishment methods and implementation techniques of indoor high precision true north azimuth reference are discussed. This reference is maintained by two parallel optical tubes and a planar mirror, and is calibrated by two Leica5100A 0.5″ electronic theodolites using two theodolite astronomical orientation methods. The measured results show that in the environment of great indoor and outdoor temperature difference and humidity difference on October 19 and 20, 2017, only by a total of 6 set observations through two periods of time, the mean square error of the three azimuth references is as high as 0.17″, 0.18″, 0.20″ respectively. Re-testing on October 11 and 12, 2018, the mean square error of the three azimuth references is 0.47″,0.30″,0.48″ respectively, and the re-test results about one year later show that the three references changes were +3.84″, +1.96″ and +3.80″ respectively, which indicates that the references are very stable and the proposed method is very effective.