Sliders 1 and 2 move along fixed guides p and q whose axes are perpendicular to each other. Extensions a and b of sliders 1 and 2 move in cross-shaped slider 3 whose guides are perpendicular to each other. Link 4 is connected by turning pair C to slider 3 and moves in cross-shaped slider 5. Slider 5 moves along the axis of link 6 which is connected by turning pairs A and B to sliders 1 and 2. When sliders 1 and 2 move along guides p and q, point K of slider 5 describes an arc of an astroid with the equation x^(2/3)+y^(2/3)=l^(2/3) where l = A͞B. At the same time, straight line AB envelops the astroid.
$1162$LG,Ge$