added function to compute ax distance of shifted gears

gearfunc/computation.py

@@ -0,0 +1,23 @@
+import numpy as np
+from scipy import optimize as opt
+
+def computeShiftedGears(m, alpha, t1, t2, x1, x2):
+    """Summary
+    
+    Args:
+        m (float): common module of both gears [length]
+        alpha (float): pressure-angle [rad]
+        t1 (int): number of teeth of gear1
+        t2 (int): number of teeth of gear2
+        x1 (float): relative profile-shift of gear1
+        x2 (float): relative profile-shift of gear2
+    
+    Returns:
+        (float, float): distance between gears [length], pressure angle of the assembly [rad]
+    """
+    inv = lambda x: np.tan(x) - x
+    inv_alpha_w = inv(alpha) + 2 * np.tan(alpha) * (x1 + x2) / (t1 + t2)
+    root_inv = lambda x: inv(x) - inv_alpha_w
+    alpha_w = opt.fsolve(root_inv, 0.)
+    dist = m * (t1+ t2) / 2 * np.cos(alpha) / np.cos(alpha_w)
+    return dist, alpha_w