The lengths of the links comply with the condition: A͞B=B͞C=B͞D=k. When stylus A is moved along curve a, slider 1 moves along the slot of link 2 and slotted link 3 turns about point B. The angle of rotation φ of measuring wheel 4 is proportional to the quantity (x-x₁)-(k²/2)∫(y²)dx.
$1318$LG,MO$