2007-02-27 10:24:24 · 4 answers · asked by michael k 1 in Science & Mathematics ➔ Earth Sciences & Geology
When I first designed them, they had plain hinged joints, but it became apparent that motion it 2 planes would be a worthwhile product improvement. I then looked at a universal joint like in an automotive drive shaft, but I hadn't yet invented the auto, so that was out...... The spherical ends came to me as I was creating another planet or 2 and realized that this shape was 'the music of the spheres'.... The rest, as they say, is history
2007-02-27 10:32:12 · answer #1 · answered by Steve 7 · 0⤊ 1⤋
It's so they can easily slide around inside of the socket. Easy way to display it: cup your left hand, make a fist out of your right hand; put your fist into the cup, the fist can slide around in the palm of your hand. That's a ball and socket joint, the humerus and femur are the 'ball' part.
2007-02-27 10:33:03 · answer #2 · answered by leslie 6 · 0⤊ 0⤋
Is is because they form ball and socket joints?
2007-02-27 10:27:07 · answer #3 · answered by Modus Operandi 6 · 1⤊ 0⤋
they are ball and joint sockets making movement in any direction easier
2007-03-02 16:11:52 · answer #4 · answered by fatdadslim 6 · 0⤊ 0⤋