Question

1. The manufacturer's technical specification for the EDMI in the Topcon GTS 213 Total Station is given as: (5mm +5pp). The instrument does not possess a dual axis compensator. You estimate that you can level up the instrument over a point to a precision of 3 On the target you place a tripod with a tribrach containing a special rotatable adaptor with a longitudinal bubble which allows it to be placed over the point with a precision comparable to the instrument 3mm This equipment configuration is used to measure the distance between the O meter mark and the 1185 meter mark on an EDMI Calibration Baseline. Compute the precision (standard deviation) of this measurement.

Answer 1

"Given that Technical specification for EDM1 = 5m + 5ppm. precision level of the instrument = + 1 - 3mm precision level of the target = + 1 - 3mm Actual distance between A and B = 1185 meters AA' = + 3mm: BB' = + 3mm AA"" = -3mm BB' = -3mm case: - Suppose level of total station is = h + 3mm (A') and level of target is = h (B) In Delta AA'B (Right angled delta) base = 1185000 mm (AB) perpendicular = 3mm (AA') hyper tense i.e. A'B = Squareroot(185000)^2 + 81 = 1185000.00000379746835442429 mm precision = 5mm + 5/10000000 times A'B = 5mm + 5/10000000 times 1185000.000037 = 10.925500000189873 mm. case: -2 Level of total station = h + 3(A') Level of target = h + 3(B') Here A'B' = 1185000 mm. precision = 5mm + 5/1000000 times 1185000 = 10.925mm. case: -3 level of total station = h + 3(A') level of target = h - 3(B"") In delta A' A"" B"" base = 1185000 mm (A'B"") perpendicular = (h + 3) - (h -3) = 6mm(A'A"") hyper tense i.e. A'B"" = Squareroot(1185000)^2 + 6^2 = 1185000.00001589mm \r\n "