I have a chain of similar pendula which is mounted equidistantly along a horizontal axis with adjacent pendula being connected with light strings. Each pendulum can rotate within the axis but can not move sideways. at the page http://btakashi.jp/archives/935 scroll to the bottom of the page and there is a pdf file to look at the image Some big force is needed aside from the motor to have the pendula spin connected to each other, and I cannot use my hand because it is inaccurate. So.. what kind of forces can be used as the "some big force"? Also, how should I apply this "some big force" to the pendula? Again, I need a stable and strong power source.