|
Pages: 1 ... 3 4 [5] 6 7 ... 10
41
« Last post by webby2 on January 07, 2024, 06:06:35 am »
simple solutions are good.
I am however having significant issues with the plastic parts deforming and not providing for a smooth interaction, when I use force the parts are almost grating by each other instead of sliding and rolling smoothly. I have one small spot where the input force to start things moving is less than 2.4N but then things get sticky and it takes over 4N to move but then the system kind of shoots forward and stops again until I pull further on the input.
It would seem that I need to use hard surfaces instead of plastic ones.
42
« Last post by webby2 on January 06, 2024, 03:11:58 am »
I have made some parts strong enough so that I can actually see what the parts look like as they are interacting, those are the input arm and the interactive drive unit. This allows me to see what the lever system is doing as the forces are being applied and transferred from one area to another.
I have a pivot shaft that is supposed to be rigid but even with a small amount of force being transferred those rigid pivots are bending.
I am aware of these forces but I did not appreciate the reality of how large they become so I need to constrain that reactionary force issue before I can proceed.
43
« Last post by webby2 on January 05, 2024, 04:44:57 am »
I have checked the mass and force on the drop weight, 2.5N. I have that connected to a string and am running that string over a pulley so it applies its force horizontal into the system. I have taken that pulley and used the other spring scale on the other side and it shows the same 2.5N even when I am raising and lowering the drop weight.
Moving slowly I have to apply from 3.2N to 3.6N of force to raise the drop weight, this is when the drop weight is on the output side. It is almost the same for the other side, but there are some spots where the force required jumps up to almost 7N when a part transitions its orientation.
44
« Last post by webby2 on January 05, 2024, 03:11:19 am »
Just throwing this out there.
Using this design setup to cause the system to move, on the output side I need to apply approx. 1.5N of pull then to use the input side to move the system I need to apply approx. 1N of pull.
45
« Last post by webby2 on January 05, 2024, 03:03:37 am »
I am testing out a design change and have an interesting thing.
I have reduced the input\output radius, with that I can now apply approx. 15N of force on each side and nothing moves. If I want the system to rotate with this consideration in place I need to increase the force up to approx. 20N on whichever side I wish to be the driving side to move the other side at approx. 15N.
This could just be me not applying and moving things correctly but the same relationship appears to happen with more or less force being used.
I tried another one but the part was rather flexible and under force it would flex changing the rate of angular change side to side and showed a growth in force when I used the input side but the input side, due to the flex, moved a larger angle than the output side.
46
« Last post by webby2 on January 02, 2024, 06:31:52 am »
I am using a lot of bearings in this system. All those bearings are still packed with grease so they have some drag on them. I thought that I could just increase my input force and not worry about those losses so much.
I made a poor design choice\compromise in that my input interacts with a large group of levers and uses a bearing for that interaction, the bearing is supposed to run square with the lever face but my poor choice has a very small angle to the interaction and as I increase the force that angle forces the bearing to run across the face of the levers and it "pops" off of them. I increased the strength of the arm in an attempt to stop that but it still does it anyway.
Now I get to re-design all of those parts.
One interesting part to all of this is finding what WTF I need to break and redirect. I did not see where that was and am hoping that I have found the correct path to interact with. With that, I can see several ways of making that interaction if I am correct.
47
« Last post by webby2 on January 02, 2024, 05:12:24 am »
made a few more parts.
I use the spring scale on one side with no load and the scale shows next to nothing to rotate, on the other it shows up to approx 0.25N to rotate so setup of things is closer.
I am using an arm for input and output and 2 spring scales.
I have used each scale on each arm.
The input measures approx. 1.5N and the output 1.75N.
I have run this a few times but since this is not a full rotation not much can be said other than this is less than what I thought I might see.
48
« Last post by webby2 on December 21, 2023, 04:33:00 am »
I was getting inconstant tests with different sprockets, some showed no change others some change.
My frame is 2 pieces bolted together, there are many points that line up with these 2 parts BUT when I loosened the bolts and tweaked the alignment most of the "indexed" went away, unfortunately so did the reaction I was seeing from the one setup.
Conclusion: There was an internal storage and exchange that I did not understand and would most likely lead to a net zero condition.
Next step is to get back on the path I was heading, which I did and am again frustrated with issues.
What I see via a spreadsheet is that there is a potential to have a 1:1.5 relationship for work, however things load up, if you will, when trying to pass enough force to not worry about the frictional losses . So far the only thing I can say is that on one side it takes me approx. 1N to make the unloaded system move and it takes approx. 0.75N with the other side to make the system move. Same movement by the way since the sides are 1:1 that way.
49
« Last post by webby2 on December 15, 2023, 08:59:59 am »
I am focusing on the test I can do that has little to no involvement of Mr. Hand.
That test is setting the system in a particular spot, applying the rubber bands hooked on the teeth of the sprocket and a fixed point on the frame and setting the stretched length of the rubber bands the same.
50
« Last post by webby2 on December 14, 2023, 06:00:04 am »
right now as I am playing with this it is looking like it might be the slop that may be creating the motive values.
It might be that if I use the correct set of sprockets with there systems interacting and the slop is just right the system moves with some force. I have been trying the same relationship with other parts and other sprockets and I am finding that the shift is not all the same but that when there is one that the tendency is in the same direction.
Pages: 1 ... 3 4 [5] 6 7 ... 10
|
Recent Posts