Hypocycloid prove that an epicycloid with "k" cusps moves snugly inside one with "k"+1 cusps. The evolute of a hypocycloid is an enlarged version of the hypocycloid itself, while the involute of a hypocycloid is a reduced copy of itself. The pedal of a hypocycloid with pole at the center of the hypocycloid is a rose curve. The isoptic of a hypocycloid is a hypocycloid. Curves similar to hypocyloids can be drawn with the Spirograph toy. Specifically, the Spirograph can draw hypotrochoids and epitrochoids. The Pittsburgh Steelers' logo, which is based on the Steelmark, includes three astroids (hypocycloids of four cusps).
Herman Fisher manufactured 16 wooden toys which proved highly popular at the American International Toy Fair in New York City. Fisher was the president and chairman of the Fisher-Price company from its inception in 1930 to 1969. He was instrumental in building Fisher-Price into the world's largest manufacturer of preschool toys. Along with Irving Price and Helen Schelle, he established the simple but strict Fisher-Price creed: ""Fisher-Price toys should have intrinsic play value, ingenuity, strong construction, good value and action"." Herman Fisher was also instrumental in spearheading many 'firsts' in the toy industry. He coined the term “preschool toys” with the advent