Survey Retracement & Analysis Software

General Description

OVERVIEW: Triad is a very unique tool that allows surveyors to best fit a map, deed or coordinate system to an unlimited number of known points in considerably less time than any other method. Triad will perform an analysis of all points common to two coordinate systems accurately, easily and quickly. The more points, the better it works. Triad is a powerful program that organizes and documents the process of analyzing a survey retracement. The surveyor can focus on professional judgment, not the tedious task of crunching numbers. The results are summarized and statistically qualified.

TYPICAL APPLICATION: It is a well-known principal that the intent of a boundary retracement is to re-establish the lines and corners of a prior survey in their most probable locations. A common method of analysis uses coordinates to compute the inverses or connections between found monuments and compare the bearings and distances with the corresponding points on a plat or map. If the inverses are consistent in rotation and distance then those monuments are acceptable for controlling the boundary. This process will become more difficult to organize and quantify as the number of points increase. For example, four points have six possible inverses. Eight points have 28, doubling to 56 inverses when comparing the map and the field points. The time spent analyzing found monuments in this way is time consuming and costly. Triad is the ultimate solution to handle this problem.

HOW IT WORKS: Triad works by determining the parameters for a two dimensional transformation: rotation, scale and translation. These are solved simultaneously by best fitting the points in one coordinate system to the same points in a second coordinate system. The points in the first system are treated like a figure, the angular relationship between points is retained while the figure is scaled, rotated and shifted to best fit all the points in the second system. New coordinates can be computed for the boundary based on a best fit of all acceptable monuments. Alternately, if one prefers, the two best points can be fixed. A summary report is created for the job file.

ERROR TRAPPING: The trick is to quickly identify acceptable monuments. A unique feature of Triad is it's powerful blunder detection routine. This routine will instantaneously identify individual points contributing the greatest errors. Simply remove these "bad" points to obtain the best solution.

SUMMARY: Triad is used when it is necessary to relate different coordinate systems with two or more points in common. Triad is a more rigorous approach than Corpscon for an accurate conversion of state plane coordinates from NAD 27 to NAD 83. In control surveys use it to compare the new measured positions with previous coordinates to get "tied-in" to an existing survey instantly with confidence. Use it to estimate the compass and chain index necessary for retracement of ancient surveys. In GIS applications it is great for hooking record maps together. Triad has been in wide use in the US and around the world since 1991. Developed by a GPS consultant, licensed boundary surveyor and programmer with over 20 years experience. There is no exaggeration to the statement that Triad will accomplish in seconds, what otherwise may take hours!.

Tel. 805-964-3520