Solutions: COGO Intersections & Transformations

 

Problem (1)

To determine the horizontal distance between the tip of a lightning rod atop a smokestack (LR) to the top of a tall flagpole (FP) a surveyor used two instrument setups (1 and 2) and measured the horizontal angles shown on the diagram. She also measured the horizontal distance between the two instrument locations as 552.36 feet.

ss cogo p3

Using these measurements, what is the horizontal distance from the lightning rod to the flagpole?

Solution

 


Problem (2)

The survey of a remnant parcel was referenced the east line of the southeast quarter of Section 21, line E21-SE21. For project coordinates, the surveyor assumed 10,000.00 ft N and 6,000.00 ft E for point E21 and due South for the direction of line E21-SE21. At point point E21 he measured 2637.41 ft to point SE21, 647.83 ft to point A, and  81°15'47 angle right to point A.

Post-adjustment coordinates of the remnant parcel corners were:

Point

North (ft)

East (ft)

A

9901.596

5359.688

B

9668.352

5270.827

C

9771.088

5034.135

 

The Regional Planning Commission (RPC) GIS system is based on a multi-county coordinate system using metric units. Its coordinates for points E21 and SE21 are:

Point

North (meters)

East (meters)

E21

43,827.359

19,231.752

SE21

43,023.821

19,200.333

Using a coordinate transformation, determine the bearing (to 01") and length (to 0.001 meter) of each remnant parcel line expressed in the RPC GIS coordinate system.

Solution