The offsets from tangents may be calculated and set to get the required curve.
The offsets can be either radial or perpendicular to tangents.

(i) Radial offsets: Referring to Fig. 2.8, if the centre of curve O is accessible
from the points on tangent, this method of curve setting is possible.

Fig. 2.8

Let 1) be a point at distance x from 7. Now it is required to find radial
ordinate O, = DE, so that the point C on the curve is located.
From A ൨7൧. we get

OD? = OT? + 720:
(R + 02 = ‏2ج‎ +x

ie. ‏دع جره‎ (+ ष्ट
or ©. = പ്‌ 2 ‏(2:12).۔۔‎
‎An approximate expression O, may be obtained as explained below:

ன ರ ட ஏர ‏وت کو‎ ಲಬ ಅಲಂಅಾಅ|್ವಅ__್ಲ ಲ _۰ = ‏ل‎ R27 +x? -_ ^र തത്തെ

3) a)