Tarsier79 wrote: ↑Wed Oct 20, 2021 1:45 am
... here is where I did an early investigation into cams. The same principle applies. The forces are reasonably easy to calculate. viewtopic.php?p=74506#p74506
Thank you for linking this valuable resource material.
There are several main negatives and this leverage issue / cams is one of them.
The lifting of the weights is simple. So long as you move a weight way from the inner position and back again on the downward side.
This little imbalance pumps up the rotation rate.
That will balance the wheel and a new weight will be available at the top.
Regards
Last edited by agor95 on Wed Oct 20, 2021 2:59 pm, edited 1 time in total.
[MP] Mobiles that perpetuate - external energy allowed
Tarsier79 wrote: ↑Tue Oct 19, 2021 7:01 pm
The description of the Marquess' wheel makes no sense to me. Why would you want the weight to move further from the center after passing the diameter line of the lower side? Is the line horizontal or vertical? Also he uses the word 'hung'. So I suspect it is a simple corded OB wheel.
I am really ropey on hanging weights. Just trying to calculate the force vectors etc.
Odd, I posted a relpy to your quote but it does not seem to be present?
Anyway the diameter line is more likely to be horizontal.
The further from the center makes sense if the hanging weight could swing like the first image but the second image with confined weights has useful qualities.
Note. The weight at the top has been accelerated laterally and then is decelerating. That can be seen more in the bottom right quadrant
in the first image.
Regards
Last edited by agor95 on Wed Oct 20, 2021 3:28 pm, edited 2 times in total.
[MP] Mobiles that perpetuate - external energy allowed
Fletcher wrote: ↑Tue Oct 19, 2021 8:28 pm
Here's a pic of the Marquis's wheel from the Ord-Hume book mentioned in earlier threads about this wheel.
...
In many ways this very simple and easy to follow illustration drives the message home, or should do !
It looks like three weights should be the minimum number that can be used.
It does beg the question did Bessler do the same with eight?
Regards
Last edited by agor95 on Wed Oct 20, 2021 10:09 pm, edited 1 time in total.
[MP] Mobiles that perpetuate - external energy allowed
No, because it doesn't work. One of the problems, the weight doesn't magically suddenly hang from the other point. The other suspension point has to lift compared to the weight, the rotation of the wheel lifts the weight. Even if there is positional over-balance, the negative torque of lifting each weight into position will counteract most, if not all positive torque.
The problem is; if you turn the wheel a little bit there are 18 weights above the axle, and 22 below it. Which means it wont work--------------------Sam
Sam Peppiatt wrote: ↑Thu Oct 21, 2021 1:54 pm
agor95,
The problem is; if you turn the wheel a little bit there are 18 weights above the axle, and 22 below it. Which means it wont work--------------------Sam
Have you calculated the torque for each weight so you can confirm they cancel out?
Well I am reducing the wheel design to 3 compartments.
Then we can confirm this understanding.
Regards
Last edited by agor95 on Thu Oct 21, 2021 2:10 pm, edited 1 time in total.
[MP] Mobiles that perpetuate - external energy allowed
This is true. There are 8 significant rates of change in torque in a full circle.
Tarsier wrote:Even if there is positional over-balance, the negative torque of lifting each weight into position will counteract most, if not all positive torque.
That has been the death of many excellent designs.
I suppose that is the real problem to solve.
Lifting with a pendulum doesn't solve the problem.
Last edited by WaltzCee on Thu Oct 21, 2021 4:18 pm, edited 2 times in total.
This is an image below of the base structure of a simplified Marquis Wheel.
The 40 components on the second image have been reduced to 3 components. For aesthetic I have used the AP frame to connect the square components to the hub.
As the model is 3D and can be aminated and test readings taken then graphed.
I have all expectations the understanding posted will be supported.
P.S. I am working on the anchor point rope and weights.
Regards
Last edited by agor95 on Thu Oct 21, 2021 6:20 pm, edited 2 times in total.
[MP] Mobiles that perpetuate - external energy allowed
Even if you give it the benefit of the doubt, there will be 19 weights above the center line and 21 below. Don't you see? The wheel will be bottom heavy / OOB by 100 pounds. There won't be any torque----------------------------------Sam