The lengths of the links comply with the conditions: B͞C=A͞D, A͞B=D͞C, A͞E=E͞B=E͞F and C͞F=0.27A͞B. Figure ABCD is a parallelogram linkage. Link 1 turns about fixed axis A and is connected by turning pairs E and B to links 4 and 2. Link 2 is connected by turning pair C to links 5 and 3. Link 3 turns about fixed axis D. Links 4 and 5 are connected by turning pair F. When link 1 turns about axis A, point F describes a path of which a certain portion approximates straight line q-q.
$697$LW,GI$