Spectra Precision Survey Pro v4.5 Recon and Nomad Reference Manual - Manual (Page 388)

Survey Pro Reference Manual
R-380
• Chord Offset: provides perpendicular offset
information from the chord (the line from the PC
to the PT) for each station on the curve. PC
deflection information is also provided. The
results are given in the following format:
o Station
: is the current station on the curve.
o Chord dist. : is the distance on the long chord
from the PC (toward the PT) where the
perpendicular offset occurs.
o Chord offset : is the distance to the current
station on the curve, perpendicular to the long
chord.
o PC Deflection : is the angle to turn to the
current station, as if occupying the PC and
backsighting the PI.
o Chord Length : is the distance from the PC to
the current station on the curve.
RP
PT
PI
PC
Current
Station
Chord
Offset
Chord Dist.
Chord Length
PC Deflection
Chord Offset
The first known part of the curve is defined by one of the following:
• Radius : is the distance from the radius point to the curve.
• Delta : is the deflection angle.
• Degree Arc : is the deflection angle that results in a 100-ft. arc
length.
• Degree Chord : is the deflection angle that results in a 100-ft.
chord length.
The second known part of the curve is defined by one of the following:
• Delta : is the deflection angle.
• Length : is the arc length.
• Chord : is the chord length.
• Tangent : is the distance from the PC or PT to the PI.
• Mid Ordinate : is the distance between the curve and the chord at
the center of the curve’s length.