The mechanism is based on slider-crank linkage ABC. Added to this linkage is a double guiding element consisting of two sliders, 5 and 6, connected together by turning pair E. The mechanism is intended for tracing the body and space centrodes of links 2 and 4. The tracing stylus is at the centre of pivot E. The mechanism is shown set up for tracing space centrode Cs, i.e. for the case when link 4 is fixed. To trace the body centrode Cb, pivots B and C are secured to the fixed plane, and link 4 is released. Centrodes of various shapes can be obtained by varying the lengths of links 1 and 2. This is accomplished by adjusting pivots B and C in slots F and G of links 1 and 2.
$1244$LG,Ge$