Posted by Scott Ellis (216.87.95.64) on March 08, 2002 at 01:53:12:
In Reply to: CG Path posted by Christopher on March 05, 2002 at 22:16:37:
I am probably not your intended respondent, since I am not "fluent" in physics related math.
However, I do appreciate your post and I have a question for you. You say that the machine has "trigger points" that cause the masses to shift. Shifting weights requires energy, so where is that energy coming from? It is easy enough to shift weights around in a scheme, the trick is making that weight shift actually result in "re-guaging" the mechanism for the next weight shift to occur.
If you can address this issue, maybe you will get a response from someone more able than myself!
-Scott
: I have something that I'd like to run past anyone who is fluent
: in physics related math...
: I am toying with a wheel that has "trigger points" every 45 degrees.
: When a "trigger point" (TP) is reached weights shift and the
: Center of Gravity (CG) moves to the right. This shift unbalances
: the wheel and causes it to turn, hopefully, far enough to reach
: the next TP or beyond.
: I have calculated the CG at 7 points of rotation between 0 and 45
: degrees (more than that is not necessary since the CG returns to
: the 0 x,y location if we make it to the next TP. In other words,
: the CG path repeats every 45 degrees of rotation.
: Assuming (0,0) is the center of the wheel, the total of all the
: weights is approx. 60 lbs, the wheel radius is 50 inches,
: and the wheel is rotating clockwise, would the following CG path
: indicate OU?
: Degree of Rot. CGX CGY Theta
: 0 2.82 -2.82 45.00
: 7.5 2.43 -3.16 37.50
: 15 1.99 -3.45 30.00
: 22.5 1.53 -3.68 22.50
: 30 0.73 -3.46 11.93
: 37.5 0.03 -3.10 0.52
: 45 -0.56 -2.63 -12.12
: It looks to me like there are 5 points to the right of center
: where speed/rotation would be increased, one point in the center
: which would probably have little effect, and one point to the left
: to slow it down. The start and end Y locations are not even that
: different from one another so it's not like the CG has to climb
: some gigantic hill at the end.
: Seems straightforward to me but I MUST be missing something...