Spectra Precision FOCUS 2 Series - Shift Value?R; Spiral Transition Coordinates; Tangent Distance

SPECTRA PRECISION FOCUS 2 SERIES TOTAL STATION USER GUIDE
B – Calculate Road Alignment
155
Shift value ΔR
ΔR = E − R(1 − cosτ)
ΔR = 6.777 − 100(1 − cos18°20’06’’)
= 1.700
Symmetrical spiral transition: Δ R1 = Δ R2
Spiral transition coordinates
N
m
= N − R s i nτ = 63.348-100sin18°20’06’’ = 31.891
Symmetrical spiral transition: N
m1
= N
m 2
Tangent distance
In this example:
LA 111°55′47″
1
LAsin
----------------
1
LAtan
----------------
=cot,=csc,=
D
1
R
LA
2
--------


tan R
2
LA()cscΔ R
1
LA()cotΔ N
ml
+–+=
LA 111°55′47″
1
LAsin
----------------
1
LAtan
----------------
=cot,=csc,=
D
1
100 111°55′47″ 2⁄()tan 1.7 1 111°55′47″sin⁄()1.7 1 111°55′47″tan⁄()31.891+–+×=
148.06015 1.8326 0.6844 31.891+++=
182.468=
D
1
D
2
=