...What I *imagine* happening -- if I imagined correctly -- are three actions occurring simultaneously to propel the wheel:
1. Net torque on descending
2. 3:00 lever striking the rim stop (think hoop and stick game)
3. Red weights cycling on one side to maintain the net torque
Fletchers Sim seems to tell a different story:
1. No net torque on descending
2. No force pushing to hit on the rim stops
3, ---Not simmed---
4. Levers at top not pulled over.
The force you need to compress your spring won't be coming from the lever/weight combo, but has to come from rotation forcing the spring to compress under the lever. (We don't have rotation to begin with).
mryy , you mention non tethered-ness is what makes it work , if you look at your designs all those levers and weights are tethered which is no different than what you propose is the reason why overbalance designs fail , perhaps part four ? :)
Last edited by johannesbender on Fri Jan 20, 2023 10:08 am, edited 1 time in total.
...What I *imagine* happening -- if I imagined correctly -- are three actions occurring simultaneously to propel the wheel:
1. Net torque on descending
2. 3:00 lever striking the rim stop (think hoop and stick game)
3. Red weights cycling on one side to maintain the net torque
Fletchers Sim seems to tell a different story:
1. No net torque on descending
2. No force pushing to hit on the rim stops
3, ---Not simmed---
4. Levers at top not pulled over.
The force you need to compress your spring won't be coming from the lever/weight combo, but has to come from rotation forcing the spring to compress under the lever. (We don't have rotation to begin with).
Not so fast, T7. The sims are based on a older version where the cords are taut against the 3:00 lever that carries the red weight. That lever needs to swing freely and the cords about it have to be loose. See my latest uploads. The second sim has the wheel turning a bit with the insertion of stops so there is net torque. The sims are missing springs (and one flying red weight). Springs under tension want to rotate the levers clockwise and the stops don't quite convey that, I don't think.
johannesbender wrote: ↑Fri Jan 20, 2023 9:07 am
mryy , you mention non tethered-ness is what makes it work , if you look at your designs all those levers and weights are tethered which is no different than what you propose is the reason why overbalance designs fail , perhaps part four ? :)
Not so fast, JB. We're still on part three. Did you not notice the red weight being flung to the lever above it? It's in the air ...
Tarsier79 wrote: ↑Fri Jan 20, 2023 7:51 pm
I added a 4 because of its implications to your final design.
How do you compress a spring when the system has nothing to give?
Come on T79. You eagerly draw conclusion and pose a question based on a couple of draft sims that aren't faithful to my design (no springs, no red weight). Not so fast ...
Oh and there is a 4 already ... as in the 1:4 Ratio.
I am still pondering over the optimal length of the lever in relation to the wheel size. I looked for B. clues and the one about the peacock in the AP might be relevant. I grabbed an online image of a peacock. I traced two circles, a small one around the bird's body for the grindstone and a large one around the open tail profile for the wheel -- pretty much eyeballing it so take with a grain of salt.
I found the ratio of the grindstone radius to lever length is about 1:5 or 1:6. Cool huh? I'll see if I can incorporate that in my next design. Thank you JohannB (Bessler that is) !
Come on T79. You eagerly draw conclusion and pose a question based on a couple of draft sims that aren't faithful to my design (no springs, no red weight). Not so fast ...
Not faithful to your design? I believe the base mechanism was simmed pretty well. It is the base principle that has to work. You can't base an entire mechanism on a flawed principle and expect it to work just because you add a spring or a red weight.
Also a 1:4 or 1:5 or 1:6 ratio is pointless without something to apply it to, much like many of Besslers clues.
Have you tested a spring/lever combo yet to see how much effort is required to compress it compared to shooting a small weight?
Last edited by Tarsier79 on Fri Jan 20, 2023 11:28 pm, edited 2 times in total.
Come on T79. You eagerly draw conclusion and pose a question based on a couple of draft sims that aren't faithful to my design (no springs, no red weight). Not so fast ...
Not faithful to your design? I believe the base mechanism was simmed pretty well. It is the base principle that has to work. You can't base an entire mechanism on a flawed principle and expect it to work just because you add a spring or a red weight.
Really? Going by your logic simming the MT drawings -- which are base mechanisms -- will reveal flawed designs. So that makes them unusable? Didn' B say that combining their movements or adding a primer/structure will lead to a runner? Surely your logic contradicts his statements, no?
Also a 1:4 or 1:5 or 1:6 ratio is pointless without something to apply it to, much like many of Besslers clues.
Absolutely! How about applying a prime mover to the design during the sim? Then again, how good are sims in predicting a runner? I believe these programs have built-in constraints and limitations but some individuals possibly yourself give a little too much credence to them ... For me a real-world build is the absolute test.
Have you tested a spring/lever combo yet to see how much effort is required to compress it compared to shooting a small weight?
Have not. If you have the answer produce it here for us ...
but some individuals possibly yourself give a little too much credence to them ... For me a real-world build is the absolute test.
Simulations have their place, especially if you understand them. Real world builds are the absolute test if you actually build them, build them correctly and understand why they do what they do. It is always good when your build matches or confirms the simulation.
If you don't agree with the simulation, then build it.
Didn' B say that combining their movements or adding a primer/structure will lead to a runner? Surely your logic contradicts his statements, no?
You have interpreted Besslers comments differently to me. Your understanding of a prime mover is different to mine. I see no contradiction.
but some individuals possibly yourself give a little too much credence to them ... For me a real-world build is the absolute test.
Simulations have their place, especially if you understand them. Real world builds are the absolute test if you actually build them, build them correctly and understand why they do what they do. It is always good when your build matches or confirms the simulation.
I agree a simulation guides builds and builds confirm simulations.
One can exist without the other, but they are more effective in cooperation.
Regards
[MP] Mobiles that perpetuate - external energy allowed
The ??O$$ concept with 14 levers and at 1:5 Ratio. Inspired by the stork's bill of the Toys Page and MT 24 & 25 I connected the levers with hinged rods this time instead of cords. Unlike MT 24 & 25 the rods fold outwardly. Diagram shows wheel in the starting imbalance prior to release for spin. You likey?
In consideration of B.'s notes about MT25 the hinged rods now maintain a bent profile when fully opened. Imagery of children hand holding, feathers, one big snowflake, V's, W's ...
