Circular Curve Calculation - Sokkia im-101 Operator's Manual

25.3 Circular Curve Calculation

The coordinates of the center peg and width pegs on a circular curve can be found from the coordinates of the
BC point and IP point.
It is then possible to proceed with the setting-out of the center peg and width pegs.
AZ
P2
DL
P1
Offset
DL
Route origin
PROCEDURE
1. In the second page of the OBS mode screen, press
[MENU], then select "Road".
2. Select "Circ.Curve" to enter the Circular Curve menu.
3. Input the coordinates of the BC point (reference point), then
press [OK].
4. Input the coordinates of the IP point, then press [OK].
• The azimuth angle to the IP point can be set by pressing
[AZMTH] on the second page. Press [COORD] to return to
coordinate input.
5. Enter the curve direction, curve radius, offset, and follow-up
distance.
6. Press [OK] in the screen shown in step 5 to calculate the
center peg coordinates. The coordinates and azimuth angle
are then displayed in this screen.
QL
BL-
Q
BL
QR
R
Offset
BC point (P1)
IP point (P2)
Circular curve radius (R)
Follow-up distance (DL)
Route width (BL)
Target point (Q)
Width peg (QR, QL)
R o a d
O c c . O r i e n .
L i n e
C i r c . C u r v e
S p i r a l
P a r a b o l a
C i r c . C u r v e / C L p e g
D i r e c t .
R a d i u s
S t . o f s
S t a . . i n g
C i r c . C u r v e / C L p e g
N
E
A z mt h
WIDTH
121
25. ROUTE SURVEYING
R i g h t
8 5 . 0 0 0 m
0 . 0 0 0 m
9 0 . 0 0 0 m
OK
6 5 . 7 7 9
1 7 8 . 7 3 9
0 0 0 0 ' 0 0 "
REC S-O CENTER