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« Last post by webby2 on December 05, 2023, 05:45:22 am »
Not sure what this means.
While I am just playing and printing more parts for testing stuff.
I set things up in a strange almost backwards way, then I use Mr. Hand to hold the output still and then use the other Mr. Hand to apply force against the input arm. I then shift things so that it is close to where I think a force gain situation should be,,, now the funny thing happens. I move the arm and of course the output moves then I take Mr. Hand on the output and I increase the resistive force he is applying. Well, Mr. Hand on the arm does not feel that increase in force but several of the parts bend and flex more, as I would expect from the increase in force from the output.
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« Last post by webby2 on December 04, 2023, 05:27:50 am »
This should not need to be said, but, no engineer would design one of my systems to work the way I am using it
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« Last post by webby2 on December 04, 2023, 04:20:51 am »
I have a build error that I did not know about. I have 8 sub-systems with a part that connects to all of them and they all are supposed to be in sync with their motions and stuff, well somehow either a design error or a slicing error or a Freecad error, the systems are sort of indexed so that they all only line up when the parts are put together in one orientation and that still does not work nicely. The system is supposed to allow for a free rotation between all the parts but as the system rotates it starts to bind and that spring loads the actual parts so there are 4 positions that it wants to stop in. This is not a good thing for me.
This test-part was setup so that I could use it for testing 2 different thoughts on how to transfer the work.
One way would require that I flip the input and output functions at the appropriate time while maintaining a constant reactionary condition. I could see Bessler using something like this for his wheel since Gravity is directional it would provide a means to facilitate the flip and then he might be able to use the constant reactionary condition as his actual output.
Another way, which I am preferring to use, has a constant input and constant output and no flipping required. It needs a little better relational control and I think I should use a couple of limiters.
I have made my parts somewhat weak so that I can see the forces acting upon those parts, they bend and flex and it is this bending that I am using as a visual guide for the build. Obviously the final build parts will be stronger.
Another reason I chose to use 8 sub-systems is because each one can only pass a smallish amount of torque, 8 working together means I could pass 8 times as much before failure, hence the chain and sprockets to not only pass the output via the chain but the chain was supposed to keep all the parts in sync.
What I am seeing from my flawed test-bed, going for the constant setup, is that the forces and directions are doing what I was expecting. I have taken what should be an external rotation and stopped it and turned it into a virtual rotation.
I still need to design the feedback system that is needed between to parts, one moves a little relative and the other moves more, this work is the feedback I need to build for.
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« Last post by webby2 on November 30, 2023, 03:50:31 am »
Throw away is not really correct but it kind of shares what I am not overly concerned with.
So, my test-bed allows me to transfer the work, via the perimeter of the wheels, through the system at a 1:1 rotation and a 1:1 force as seen by each wheel. I use the same size drive disc on each wheel and measure the same force and the same change in angle.
None of that should be a surprise since our math requires that this be the case as far as final values go.
I am mentioning this again because the perimeters are not the same and so there is a difference of distance traveled, this difference is made up for with the work transfer function of the designed interaction. This WTF is another exchange\conversion that happens internally, something I now have access to.
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« Last post by webby2 on November 29, 2023, 04:55:23 am »
To be a little clearer, what I think I can do is throw away the change in distance so that my input force on the 100mm is the same force out on the 80mm,,, say 1N of force in and 1N of force out at a 1:1 rotation.
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« Last post by webby2 on November 29, 2023, 04:45:45 am »
so my primary test-bed has proven many times and in different ways that my larger diameter wheel can drive a smaller diameter wheel at a 1:1 rotation and a 1:1 force for a 1:1 work transfer, it goes the other way as well.
This is all accomplished by some simple but maybe a little clever design where the hidden distance is allowed to exist. Think about this way, if I have a 100mm radius turning an 80mm radius I would need some kind of gear that has that 5:4 ratio, mine is a virtual gear but it is real enough to perform the function needed.
My new test-part is doing the same kind of thing but using a real gear instead and I am trying to design it so that it is a poor gear design, I am willing to throw away some work to losses.
I am shooting for basically a 100mm diameter turning an 80mm diameter at a 1:1 rotation and with a 1:1 force but minus those losses I am designing into the system.
I am going this rout since my chain and sprockets are not doing so well.
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« Last post by webby2 on November 27, 2023, 03:19:22 am »
My chain and sprockets have already failed in keeping things in sync. I knew they would not hold up for a long time but I thought that I would get a few weeks of testing before they went bad.
What I was playing with was making the motions and stuff that I wanted, not sure on the force values but some of the methods of interacting did work, again not sure on the force values.
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« Last post by webby2 on November 22, 2023, 06:21:35 am »
I should also mention that I made these parts fairly weak so I could see one of the forces I am trying to use.
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« Last post by webby2 on November 22, 2023, 06:19:10 am »
This is getting somewhat intriguing.
I have the system almost complete, the new part, and I made 2 crude alignment type of test parts to see about the angles and stuff. I should have a change in the force function depending upon the angles.
As I am playing with this there are a few positions I can set things into that behave a little different, that is in one setup the reaction to the"input" force drops and the system will make a fast change so I am thinking that at that relationship then if I were to keep shifting the reactionary "input" force, which has dropped, the system would keep shifting. This is close to what I am trying to do.
Another one would be using CP where the CP hold force is converted into another output work function.
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« Last post by webby2 on November 19, 2023, 03:22:09 am »
I need to design in a point of failure that will be easy to replace. I need this due to the limited force that my plastic parts will be able to handle and I would not want to break a part in the middle of everything that would require me to disassemble the whole thing to replace.
I also need to be able to amplify my input work enough to more than compensate for my frictional losses and show a gain.
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