Spiral Curve Design
This feature allows you to design a spiral curve. You will be
prompted using standard spiral curve component nomenclature.
Follow the prompts described in the Prompts section below and the
following Spiral curve data is calculated and displayed at the
command line and written to the print file.
Point of Intersection of the spiral (PI for spiral)
Tangent point of the spiral (TS for spiral)
Point where spiral meets simple curve (SC for spiral)
Radius point of the simple curve
Point where simple curve meets outgoing spiral (CS for spiral)
Point where spiral meets tangent on outgoing side (TS for
spiral)
For each of the points calculated the prompt
The Saving Point dialog (see below) will appear and allow you to
specify the point ID.
Click OK to cause the point to be stored in the coordinate
file.
At the Curve Description <enter if done>: prompt you can
either enter the description for another curve or press
<Enter> to end the command.
Prompts
Curve description <enter if
none>: This description is optional but is used to
identify the information in the results. Press Enter to end the
command.
Enter the first point:
Enter or pick a point on the tangent going into the spiral.
Enter first bearing
<100.0000>: Enter or pick the bearing from first point
to the P.I of the spiral.
Enter second point: Enter
or pick a point on the tangent going out of the spiral.
Enter second bearing
<100.0000>: Enter the bearing from second point to the
PI.
Enter Radius [Degree_of_curve]
<0.000000>: Enter or pick the radius or type "D" and
Enter to change to degree of curve prompt.
or
Enter Degree of Curve
[Radius]: Enter or pick the degree of curve or type "R" and
Enter to change to radius prompt.
Enter spiral length in
<0.00000>: Enter or pick the length of the spiral
coming from the first tangent into the simple curve. Enter a zero
for no spiral in.
Enter spiral length out
<0.00000>: Enter the length of the spiral from the
simple curve out to the second tangent. Enter a zero for no spiral
out.
Pulldown Menu Location:
CG-Survey > Cogo > Curves
Keyboard Command:
cg_scd
Prerequiste:
coordinate file
