straight line and parabola

straight line and circle

circle and straight line

circle and parabola

The body centrode rolls on the space centrode.

The space centrode rolls on the body centrode.

Both body and space centrodes may role on each other.

The body centrode never touches space centrode.

zero

maximum

minimum

varying

constant

zero

maximum

minimum

(i) and (iii)

(i) and (iv)

(ii) and (iii)

(ii) and (iv)