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Author Topic: Eccentric device  (Read 583 times)
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img  webby1
Re: Eccentric device « Reply #25 on: 2026-06-14, 05:22:29 »
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Posts: 36
Well it can not be anomalous if it is predicted, right?  So no it does not because all of the interaction have been calculated, or predicted, and I am just building to get as close to those predictions as I can.

Consistency without the electric motor generator guess work I think is the best way to move forward and so I have shifted to mechanical.

So this system will lock the mesh to arm, or sync the 2 together, with any offset values that total greater than 20mm, and as you should know, at 20mm exactly the toggle event is very unstable but as the system is moved away from that point of infinite force between the sun/ring/arm and pivot that force emerges into the real world and is what forces the arm into rotation and locking it to the mesh.  That force has a cost in the real world and it boils down to strength, the stronger the parts against the massive force the closer the offset distance can be and the less force is used by that part, so more for the output.

I have 2 bearing adapters for the ring gear and a built in 10mm offset for the pivot bearing, so that gives me the choice of using either a 0, 5, 10, 15, or 20mm ring gear offset, I am going to re-do my sun arm-gears so they have a 5, 10, 15 and 20mm offset,, so then any of those can be used for testing.
Any person with a large format 3D printer could then take my files and adjust them for there printer and print out there own test bed to experiment with,, just add bearings and screws and filament.

Here is the system opened up so you can see how simple the actual system is.
   
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Re: Eccentric device « Reply #26 on: 2026-06-21, 06:31:31 »
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the green is the input.
The gear-set is a 6/5 step down from input to output so the output arm should be 60mm for the input arm of 50mm for the system to balance in force.
The pic I have posted has the output rubber band at 70mm to have the same amount of stretch, between 40 and 42mm as the input,, resetting and retesting many times has given me the little window on the measurements but they are almost always within about 0.1mm of each other.

This then is a picture of a device in a static test state that is showing a mechanical gain for the operator.


I forgot to mention that that little gain is after all of the input costs have been paid for by the input,, so it cold be more,, it is a little sad that it is not yet at the 10:1 that the model predicts.
   
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Re: Eccentric device « Reply #27 on: 2026-06-21, 16:12:00 »
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Posts: 36
here is a link to a youtube video of Mr. Finger moving the input lever

https://youtube.com/shorts/2y2TRE8bvuo?feature=share
   
img  webby1
Re: Eccentric device « Reply #28 on: 2026-07-12, 03:56:14 »
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this new build is a deviation and I am calling it Maxwell's Engine,, the Demon sits in the gap.

This is an exploded view of the parts so far, more to design and print.
   
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Re: Eccentric device « Reply #29 on: 2026-07-12, 21:19:14 »
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this is the inside of the TT motor reduction unit
   
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Re: Eccentric device « Reply #30 on: 2026-07-28, 08:50:31 »
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the build so far
   
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Re: Eccentric device « Reply #31 on: 2026-07-30, 15:35:24 »
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printing off parts that should be the final parts,, should be because so far I have messed up a few print changes,,,,,

An interesting observation is that the "pin" when only between 2 pivot bearings can twist out of alignment, meaning that the pin is not 90 degrees vertical to the pivot bearing face,,  good thin I built in a gear sync system for that part.

With all of the test fits so far the system actually can spin very smoothly which, with all of these gears,, is a little surprising but very good.
   
img  webby1
Re: Eccentric device « Reply #32 on: 2026-07-31, 04:57:19 »
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I still need to print out some more spacers, cut 2 shafts shorter, build the electronics package, build the motor holder and the motor coupler.
It is coming along and so far it all spins fairly well.
   
img  PhysicsProf
Re: Eccentric device « Reply #33 on: 2026-08-02, 03:32:07 »
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Interesting - and clearly a lot of work!
Best wishes to your progress.
   
img  webby1
Re: Eccentric device « Reply #34 on: 2026-08-02, 06:37:16 »
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a look inside while I have the 80T gear and the TT motors removed,, a spin up test using a yellow body TT motor was interesting,, it took less to spin using the 2:1 step up and spinning the TT motors than it did to just spin the system 1:1,, using that 2:1 step up does reduce the the upper and lower gears rate of rotation,, but the TT motors are a little drag forward you know,,
   
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Re: Eccentric device « Reply #35 on: 2026-08-02, 14:19:29 »
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Posts: 36
these are only preliminary tests trying to set a base line.  On this run the Blue TT motors had a 4:3 step down ratio to the input drive gear, I am printing new gears to bring that up to a 1:1

Configuration / Setup,Input Voltage,Total Input Current (Iin​),Net Current over Motor Tare,Generated Output / Status,Bench Notes
Yellow Motor Alone (Tare),6 V,0.11 A,0.00 A,N/A,Baseline internal motor + gearbox friction.
Yellow + Bare Frame Stack,6 V,0.22 A,0.11 A,N/A,Frame bearings (8 mm shafts) & structure add just 0.11 A drag (no 80T gear).
1 Blue TT Motor (Direct Drive),6 V,0.35 A,0.24 A,5.0 V Open Circuit,Smooth single-branch baseline; yellow motor stays cool.
2 Blue TT Motors (Direct Drive),6 V,0.54 A,0.43 A,—,Linear load scaling up to 2 direct-driven gearheads.
3 Blue TT Motors (Direct Drive),6 V,0.70 A→0.95 A,>0.59 A,Stall / Thermal Limit,"Torque limit exceeded; armature back-EMF collapses, cooking motor windings."
3 Blue TT Motors (In Planetary Loop),6 V,0.31 A−0.34 A,0.20 A−0.23 A,Feedback Loop Active,Key Result: Loop force cancellation drives all 3 motors for less current than 2 direct-driven motors!
1 Blue TT Motor (Under Peak Short-Circuit Load),6 V,0.78 A,0.67 A,0.110 A−0.120 A Peak,Measured across DMM 200 mA range (∼0.5Ω shunt load). Heavy magnetic back-torque.
   
img  webby1
Re: Eccentric device « Reply #36 on: 2026-08-03, 05:21:49 »
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Posts: 36
the yellow motor was not going to cut it so I changed it out to a Blue all metal gear TT motor,, then I got carried away running some tests.
The pdf explains all of that fairly well.
It is nice when the math matches the bench,, lower draw.
   
img  webby1
Re: Eccentric device « Reply #37 on: 2026-08-04, 01:13:35 »
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Posts: 36
there seems to be an error on the calculated TT motor turn ratio,, so those conclusions are wrong.  Sorry for the confusion.
   
img  webby1
Re: Eccentric device « Reply #38 on: 2026-08-13, 12:20:42 »
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Posts: 36
The printer I used for the frame sections had an issue that I have now resolved. I reprinted those parts and also made the dual ring gear, or hybrid ring gear, a little stronger so it is less prone to deforming under load. I also found two bad pivot bearings and replaced them.

As tested:

28 bearings
17 gears

Blue motor alone: 0.07 A

1:1 direct head-to-head, 1 Blue driving 3 Yellow:
0.48–0.50 A

2:1 system, no load motors:
0.16–0.23 A

1:1 system, no load motors:
0.18–0.24 A

2:1 head-to-head through the system, 1 Blue driving 3 Yellow:
0.45–0.54 A

All tests were run at the same 6 V power-supply setting and allowed to run until reasonably stable.

These are the measured numbers from this build. They are not being presented as evidence of gain; they are simply the results from the current configuration.
   
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