Author Topic: Something different. How about this.....  (Read 7075 times)

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Re: Something different. How about this.....
« Reply #8 on: August 31, 2012, 18:47:59 pm »
http://www.ebooksread.com/authors-eng/gardner-dexter-1822-1908-hiscox/mechanical-appliances-mechanical-movements-and-novelties-of-construction-for-ala.shtml

This is the book the guy mentioned at the start....

I watched it very close...

the sin of 20° is 0,34

so the torque the ball should cause to turn the wheel is the mass of the ball times G times 0,34 times the radius of the wheel...

the problem i see is that the moment of inertial of the ball is much smaller than the rotor... thus the transference of rotation is really poor...

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Re: Something different. How about this.....
« Reply #9 on: August 31, 2012, 19:33:50 pm »
Maybe the wheel should not touch the external radius of the sphere... this way it can be out of equilibrium.... i guess... i'm building  new one with two children bicycle wheels =)

It will look just like the one in the video, except that one seems made of wood probably balsa or something else light weighted,,,


notice how the ball stands close to the corner of the magnet... maybe i need a longer magnet to achieve this effect...

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Re: Something different. How about this.....
« Reply #10 on: August 31, 2012, 20:52:45 pm »
Which kid cannot bike now anymore?
 ;D

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Re: Something different. How about this.....
« Reply #11 on: August 31, 2012, 23:43:19 pm »
Good one !

I bought a 40mm steel ball... it weights around 260g... so 2,5 newton... the wheels are plastic...



 

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Re: Something different. How about this.....
« Reply #12 on: September 01, 2012, 00:43:53 am »
Good one !

I bought a 40mm steel ball... it weights around 260g... so 2,5 newton... the wheels are plastic...

Thats a good size ball. Iron?

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Re: Something different. How about this.....
« Reply #13 on: September 01, 2012, 21:47:28 pm »
here it is.., but no success yet in making it self spin =)

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Re: Something different. How about this.....
« Reply #14 on: September 01, 2012, 22:06:01 pm »
Great second attemp, boss!
You need more magnetical attraction?

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Re: Something different. How about this.....
« Reply #15 on: September 01, 2012, 22:22:28 pm »
Actually i don't know.. i need now more time to improve it... the magnet is so strong that the ball opens the wheels making it drop.. i need better solid rotor... i'm planing to add some screws for that task...

Is really strange... how can it spin?...

 when it should be working i will make some more images...


I'm thinking if the length of the magnet and its geometrical configuration relative to the sphere diameter is a parameter to play with...