Hi all, sorry for my english and for my stupid question:
If I put one heavy weight (half cilinder) on a plane that are centered on fulcrum when I shift It (rolling), is there an "amplification" of force ? If not why ? Thanks in advanced :)
Claudio.
Weight question
Moderator: scott
Weight question
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Shift weight and pendulum
Hi, in this one I have inserted a pendulum. If "feedback line" have a mechanical system that release pendulum when it is in hight position, there is
possibility of correct work (perpetual oscillation) ?? mmm maybe inertia of heavy weight is the problem.
possibility of correct work (perpetual oscillation) ?? mmm maybe inertia of heavy weight is the problem.
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re: Weight question
Hi Claudio,
I'm not sure I understand your question so I will think about it some more. Your crescent shaped "walking" counter balance mechanisn appears to be the same or similar idea as Jan Rutkowski's.
http://homepages.picknowl.com.au/astro1/jan/
It might be a good read for you if you are not familiar with it.
As the counter weight has lateral force applied at the top it causes the counter balance to rotate. The contact point with the travel board changes position ("walking") but the CoG of the counter weight wants to work against the direction of travel. Because this all sits on a fulcrum the hope is that the counter weight will right itself & walk back up the slope after its intial displacement.
Is this correct ?
I'm not sure I understand your question so I will think about it some more. Your crescent shaped "walking" counter balance mechanisn appears to be the same or similar idea as Jan Rutkowski's.
http://homepages.picknowl.com.au/astro1/jan/
It might be a good read for you if you are not familiar with it.
As the counter weight has lateral force applied at the top it causes the counter balance to rotate. The contact point with the travel board changes position ("walking") but the CoG of the counter weight wants to work against the direction of travel. Because this all sits on a fulcrum the hope is that the counter weight will right itself & walk back up the slope after its intial displacement.
Is this correct ?
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Georg Künstler
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re: Weight question
Hi Claudio,
very simple and effective oscillation. Once started swinging by hand it will stop after a while. To overcome that stopping, you must add an additional force (i call it trouble force). Best i suggest is to stop the upper swinging pendulum suddenly against a hint. You have than a forced oscillation, ongoing. Well done. Experts must be astonished how easy you can get PM.
It is an other solution. Bravo !!
the future has begun
Georg
very simple and effective oscillation. Once started swinging by hand it will stop after a while. To overcome that stopping, you must add an additional force (i call it trouble force). Best i suggest is to stop the upper swinging pendulum suddenly against a hint. You have than a forced oscillation, ongoing. Well done. Experts must be astonished how easy you can get PM.
It is an other solution. Bravo !!
the future has begun
Georg
Re: Weight question
Claudio,unstable wrote:Hi all, sorry for my english and for my stupid question:
If I put one heavy weight (half cilinder) on a plane that are centered on fulcrum when I shift It (rolling), is there an "amplification" of force ? If not why ? Thanks in advanced :)
Claudio.
I do not see any amplification of force in your first picture, I see an ampification of leverage ratio. Same force but different distance in longer time. when weight rocks left it will add but when forced back up the incline it will take = zero.
After some real hard looking at your second picture, I believe it will come to rest at about 190 to 195 degrees from vertical. Interesting design, if it were mine I would play with the bellcrank ratios on the top left and right.
Ralph
re: Weight question
This is how I see it. If I treat the parts separately initially, it becomes easier to visualize what's happening, I think.
Firstly, imagine the crescent shaped Counter Balance weight sitting on a immoveable table top that does not have a fulcrum under it.
The counter balance is 'dynamically stable', to a point, which means that if it is rocked it will attempt to stand erect again of its own accord. This is due the contact point with the table top & the CoG of the counter weight growing further apart horizontally or reverse leverage if you prefer. In other words more force is required to displace further the counter balance. If you think about it it is like an upside down pendulum with no anchor point.
Now place the same arrangement on a see-saw instead of an immoveable table top & give it a push at the top. It is still 'dynamically stable' wanting to right itself but the see-saw dips one way so that the whole assembly looses height & this has got to be given back sometime to regauge. The angle of contact between the counter balance & the see-saw is now changed so it does not stand upright but leans, assuming it hasn't gone over its tipping point.
Is there enough energy in the system to allow it to "walk" back up the see-saw ? I don't believe so.
By using a levered pendulum does this arrangement amplify the forces ? I don't think there is any net gain in energy. In fact imo the pendulum (depending on how it is hooked up) may well just give it more stability & make it harder to displace in the first place requiring more input energy to start it oscillating & will act as a dampener.
Firstly, imagine the crescent shaped Counter Balance weight sitting on a immoveable table top that does not have a fulcrum under it.
The counter balance is 'dynamically stable', to a point, which means that if it is rocked it will attempt to stand erect again of its own accord. This is due the contact point with the table top & the CoG of the counter weight growing further apart horizontally or reverse leverage if you prefer. In other words more force is required to displace further the counter balance. If you think about it it is like an upside down pendulum with no anchor point.
Now place the same arrangement on a see-saw instead of an immoveable table top & give it a push at the top. It is still 'dynamically stable' wanting to right itself but the see-saw dips one way so that the whole assembly looses height & this has got to be given back sometime to regauge. The angle of contact between the counter balance & the see-saw is now changed so it does not stand upright but leans, assuming it hasn't gone over its tipping point.
Is there enough energy in the system to allow it to "walk" back up the see-saw ? I don't believe so.
By using a levered pendulum does this arrangement amplify the forces ? I don't think there is any net gain in energy. In fact imo the pendulum (depending on how it is hooked up) may well just give it more stability & make it harder to displace in the first place requiring more input energy to start it oscillating & will act as a dampener.
An other question
Hi, many thanks for yours answers. Counter balance idea is not mine but from Jan Rutkowski's site, I have applied the pendulum because the counter balance system intrigue me. I have an other question:
in this new picture(3) I have redimensioned the see-saw because I don't want the weight (when completely shifted) stay repartitioned on fulcrum and on "feedback line". Have I in this manner improve the system efficiency or the lever (in the box) tend to cancel this benefit ? Thanks,
Claudio.
in this new picture(3) I have redimensioned the see-saw because I don't want the weight (when completely shifted) stay repartitioned on fulcrum and on "feedback line". Have I in this manner improve the system efficiency or the lever (in the box) tend to cancel this benefit ? Thanks,
Claudio.
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re: Weight question
Welcome Claudio
In your latest drawing, can you say more about the feedback?
Is energy going down a leverage arm acting like food traveling down.
If it is energy where is it coming from.
Can you draw it with arrows pointing to the path as it increases?
This may be oversimplified but maybe you can understand what I am trying to say.
If you draw a ball rolling down a slope, you can see the path of force by drawing arrows at the two points of force. One force is weight, another is slope. Another arrow can be drawn along the front side of the ball and shows that the ball has a curve.
The front of the balls curve shows that the ball continuously has its own surface to ride on.
The back of the ball has a curve that shows that the ball is going away from the sloped surface.
More ball is going forward than is staying behind, so it continues to go forward.
Any feedback on your feedback system would help me understand what you have designed.
In your latest drawing, can you say more about the feedback?
Is energy going down a leverage arm acting like food traveling down.
If it is energy where is it coming from.
Can you draw it with arrows pointing to the path as it increases?
This may be oversimplified but maybe you can understand what I am trying to say.
If you draw a ball rolling down a slope, you can see the path of force by drawing arrows at the two points of force. One force is weight, another is slope. Another arrow can be drawn along the front side of the ball and shows that the ball has a curve.
The front of the balls curve shows that the ball continuously has its own surface to ride on.
The back of the ball has a curve that shows that the ball is going away from the sloped surface.
More ball is going forward than is staying behind, so it continues to go forward.
Any feedback on your feedback system would help me understand what you have designed.
JB Wheeler
it exists I think I found it.
it exists I think I found it.
re: Weight question
Sorry, this post was pulled as subjet has been covered,
How it work (maybe)
Hi Wheeler,
the term feedback in the picture is referred to the (descending) force that occours when the heavy weight is shifted left or right (on the oscilling plane) by the pendulum swinging. Sorry but it is difficult for me explain my picture with correct words, my english is horrible I am italian. I wish my words are enought to understand my design.
Claudio.
the term feedback in the picture is referred to the (descending) force that occours when the heavy weight is shifted left or right (on the oscilling plane) by the pendulum swinging. Sorry but it is difficult for me explain my picture with correct words, my english is horrible I am italian. I wish my words are enought to understand my design.
Claudio.
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re: Weight question
Thanks your writing is fine
Is this what it would look like while in swing?
Is this what it would look like while in swing?
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JB Wheeler
it exists I think I found it.
it exists I think I found it.
Example
Swinging pendulum on the right side cause heavy weight roll to the right side on the oscilling plane, the weight pull down the "feedback line" but I don't know about the forces in this system, maybe do not correctly work. I want try to create a prototipe for testing this theory.
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re: Weight question
Looks good, but I think you will be pushing the weight with the pendulum.
I think Jim_Mich can show you how this system works.
I think Jim_Mich can show you how this system works.
JB Wheeler
it exists I think I found it.
it exists I think I found it.
re: Weight question
The system looks like you would add a slide or cam follower at green horizontal arrow
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JB Wheeler
it exists I think I found it.
it exists I think I found it.
cam follower
yes, cam follower (with ball bearing) is what I have in mind (the best for minimizing friction in that position). I think I can get better situation if horizontal red line is connected more Up on pendulum axle (near the fulcrum) . It's so hard for me to figure this system whitout a real prototipe :)