Peaucellier Mechanism:
From fig, point A is constrained to move along The circumference of a circle with fixed diameter OP.
AC = CB = BD = DA ; OC = OD ;
OO1 = O1A
From the right angle triangles ORC and BRC
OC2 = OR2 + RC2 BC2 = RB2 + RC2
Now,
OC2 - BC2 = OR2 + RC2 - RB2 + RC2
= OR2 - RB2
= (OR + RB) (OR - RB)
= OB X OA
