HEIDENHAIN TNC 620 (73498x-01) ISO programming - Manual (Page 216)

216 Programming: Q parameters
8.4 T
rig
onometr
ic functions
8.4 Trigonometric functions
Definitions
Sine, cosine and tangent are terms designating the ratios of sides of
right triangles. In this case:
where
„ c is the side opposite the right angle
„ a is the side opposite the angle
α
„ b is the third side.
The TNC can find the angle from the tangent:
α
= arc tan (a / b) = arc tan (sin
α
/ cos
α
)
Example:
a = 25 mm
b = 50 mm
α
= arctan (a / b) = arctan 0.5 = 26.57°
Furthermore:
a² + b² = c² (where a² = a x a)
b
c
a
Þ
Sine: sin
α
= a / c
Cosine: cos
α
= b / c
Tangent: tan
α
= a / b = sin
α
/ cos
α
c (a² + b²) =