dragareacalculator.py

import math
    

#example values
R=60
Tw=R/2
W=30
L=45
θ=math.pi/4

r1 = (math.sqrt(((Tw - W / 2) ** 2) + ((R + L/2) ** 2)))

r2 = (math.sqrt(((((Tw - W / 2) ** 2) + (R - L/2) ** 2))))

r3 = (math.sqrt((R + L/2) ** 2 + (Tw + W/2) ** 2))

r4 = (math.sqrt(((R - L / 2) ** 2) + ((Tw + W / 2) ** 2)))

θr1 = (math.atan((Tw - W / 2)/(L/2 + R)))

θr2 = (math.atan((Tw - W/2)/(R - L / 2)))

θr4 = (math.atan((Tw + W / 2)/(R - L / 2)))


θT3 = θr2 - θr1

HT3 = r2 * math.sin(θT3)

HT4 = L * math.sin(θr4)

HT5 = math.sqrt((W ** 2) - ((r4-r2)**2))

Turnangle = θ - θr1 + θr4

overall = ((Turnangle)/2) * r3 ** 2
print(f"overall {overall}")
T1and2 = ((r3-r1) * (W))
print(f"T1and2: {T1and2}")
T3 = ((r1-r2) * HT3) / 2
print(f"T3: {T3}")
T4 = ((r3-r4)*HT4)/2
print(f"T4: {T4}")
T5 = ((r4-r2)*HT5)/2
print(f"T5: {T5}")
Innercircle = (Turnangle/2) * r2 ** 2
print(f"innercircle {Innercircle}")

areashaded = overall - T1and2 - T3 - T4 - T5 - Innercircle
print(f"shaded area: {areashaded}")

#result is 4026.4 square units, 3.7% off of a result obtained with CAD.