a = CurveCartesian(2 * cos(t) + cos(2 * t), 2 * sin(t) - sin(2 * t), t, 0, 6.283185307179586)
t = 0.4 (slider from 0 to 6.283185307179586, step 0.1)
P: (2 * cos(t) + cos(2 * t), 2 * sin(t) - sin(2 * t))
M: (2 * cos(t), 2 * sin(t))
d = Circle(M, 1)
b = Segment(M, P)