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« Last post by webby2 on September 01, 2023, 04:20:23 am »
I am making parts so that I can feel what is happening and then make adjustments as I think I need to.
Here is the funny thing, I need to make my force input as close to only force potential as I can but I know that I can not make it perfect. What I have so far is an input force system that has far less unwanted work needed than the work I should be able to take out,, I think.
I am not using constraints to keep things lined up perfect, example: I have a bottom part that needs to be free to rotate on its axle, well I am using a large wheel that is free to roll on a hard surface with the axle having a bearing for the part to rotate on, so I am not keeping that point in perfect alignment but rather looking at the force that the large wheel is trying to shift with, and then making assumptions that to move that wheel is the work input I would need to provide.
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« Last post by webby2 on August 30, 2023, 03:38:22 am »
What I think I am seeing is that the very methods we use to constrain and design a system is what forces the system to behave the way it does. If we want the system to behave differently then we need to use a different methodology.
My test-bed, as it sits right now, shows me where the zero distance to infinite force is and why, if that is allowed to exist in all aspects, it stops the system from doing anything different than what would be expected.
My test-bed, as it sits, has demonstrated that if I use a standard method of interaction that I get the anticipated 1:1 transfer.
My test-bed breaks the force triangle in one way while still being a mechanical system with everything connected, this allows for a new "path" to exist. I think I understand another way to break the force triangle and allow for another "path" to exist through the very same parts.
Using an alternate method then, and not constraining all points as is usual, should allow my test-bed to behave in a non-standard way.
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« Last post by webby2 on August 29, 2023, 04:48:40 am »
I'm just going to put this out there.
A square does not collapse symmetrically as seen by the center.
Think about it, pulling the 2 cross corners together you take away 2 distance units for an increase in change of 0.82 distance units.
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« Last post by webby2 on August 19, 2023, 02:36:02 am »
To add a little more.
I am using a motion input and a hold torque, if for nothing else it identifies the 2 inputs.
As I change the relationships I go from high hold torque and a lot of motion force to a lower hold torque and an almost zero motion force, I keep changing the relationships and the hold torque goes down to almost zero and the motion force goes high.
My 2 inputs are making the input needed to hold the weight up and move it and they are splitting that needed work dependent on there relationship to each other and not the final work needed. The final work needed describes the total work that the 2 inputs need to provide.
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« Last post by webby2 on August 18, 2023, 04:33:46 am »
I am trying an old design for a part and while those parts are printing I have been playing with my test-bed as it is.
To date my tests are showing for the subsystems that they create a 1:1 relationship when I use them one way, a more standard usage. I have been playing with combining 2 of the subsystems and seem to have an interesting reaction when I try and run things backwards if you will. What I mean is, that using weights and I try an hold one up while having the other counter-balance the elevated weight I can get into a setup where my moving force is almost nothing but the needed torque to hold the elevated weight up is a fair amount, the setup wants to drop the elevated weight and to stop that I need to supply an input torque separate from the moving force and when I get the torque close enough and the moving force in the correct relationship, the moving force drops way down while the holding torque drops a little. My assumption would be that when the correct conditions are met that I would have a holding torque that needs to move along with the moving force and that moving force should drop to zero leaving me with a "sink" or, to get no work out and allow a motion I would need to supply input work, the holding torque and the rotation of the system just to maintain the height of the elevated weight and have it move horizontally.
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« Last post by webby2 on August 15, 2023, 06:56:16 pm »
I am choosing my relationships and dimensions,, so just to be clear these setups and conditions are special use cases and no conclusions can be drawn except that for these conditions I have chosen I can have these interactions.
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« Last post by webby2 on August 15, 2023, 03:38:24 am »
An observation.
I choose the relationships I want to run with and then design the ideal path for the rotating force vectors. This path does not have a dimension to it, it may have a length dependent on angle and displacement but the actual path has zero 3d value, it is a moving scalar.
When I add a dimension to that path things break, that is there becomes a point where the path needs to have a negative distance. In my actual test-beds I have blamed it on slop and printer error and stuff like that as well as issues with the program I use. The larger I make the system the smaller that point becomes and I have just removed material to clear the issue. This point appears as a binding point in my test-beds and I did not think about it at all. That was until I tried to design the system smaller and my program was giving me a strange shape that at first did not make any sense. I have had some issues with the program making the part I want but I figured out a way of dealing with that and just went on my merry way but not when I scaled things down except for the path dimension.
So when I take this ideal dimensionless path and add distance to it, around the point where the relationships change to an infinite force and zero distance with the oppositional component of zero force and infinite distance, this negative distance comes into existence. I think that the force side might also go into a negative value, not to be confused with direction of force, but I have not looked into that.
Anyway, in my test-bed I am simply going to omit the sections where this occurs and provide with enough overlapping points that the system stays balanced.
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« Last post by webby2 on August 07, 2023, 11:54:28 am »
forgot to mention that after I got those parts correct is when I realized that that is not the way to do it.
Sometimes you want a torque and sometimes you want a leverage, using the wrong one may provide for the same outcome or it may add things you don't want or not add something you do want.
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« Last post by webby2 on August 07, 2023, 11:45:38 am »
got those working correctly now to modify a few more parts so that they fit and function correctly.
Funny thing,, I sometimes do things that make no sense, or, for the most part, it would seem that doing it this way should be no different than that way, but sometimes things behave differently and then I have to figure out why. This is where I am at with this test-bed. I could make one part much easier but then it does not behave the same as the way I am using it within my test-bed even tho in one sense the end result is the same thing.
I realized that I need to make a similar change in method for another part, even tho the end result is the same, doing it "another" way should make it behave differently within my test-bed.
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« Last post by webby2 on August 03, 2023, 03:46:10 am »
annoying thing when you keep designing a few parts wrong, print them and try them and that is when you find out you goofed.
I finally took the time to draw the parts freecad and their actual relationships to each other to get them correct.
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