doug72

Mock "Perpetual Motion" - GBC Mark 2 version (DONE)

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Hi Doug. Interesting solutions. The last one kind of looks like a clock. I know there are some LEGO clock builders on this forum. Perhaps you could take a look at one of their threads? Because a clock is also basically a stepper-mechanism.. The clocks I have seen only use a weight and gravity to power the step, so I would suggest that you could convert a clock mechanism (gravity) to motor driven with using just one motor.

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1 hour ago, Sjoemie himself said:

Hi Doug. Interesting solutions. The last one kind of looks like a clock. I know there are some LEGO clock builders on this forum. Perhaps you could take a look at one of their threads? Because a clock is also basically a stepper-mechanism.. The clocks I have seen only use a weight and gravity to power the step, so I would suggest that you could convert a clock mechanism (gravity) to motor driven with using just one motor.

Thanks, will take a look the clock ideas.
Happy at the moment with the two motor solution for bucket wheel.
Changed the 2L stop pins for 2L pin/ ball, which work much better with the knob gear.

Now working on the drive to the two arm ball lift and as I suspected this has added more resistance into the system and slowed the bucket wheel rotation so it does move onto the next step. More trials required for the differential friction system.

Also due to gearing backlash in the drive from the BW, the two arm ball lift does not always stop at correct position.
So it looks like I will have to build a stepper unit for it but syncronised somehow to the bucket wheel using an output from the M motor.

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On 28/11/2017 at 10:29 AM, Sjoemie himself said:

Hi Doug. Interesting solutions. The last one kind of looks like a clock. I know there are some LEGO clock builders on this forum. Perhaps you could take a look at one of their threads? Because a clock is also basically a stepper-mechanism.. The clocks I have seen only use a weight and gravity to power the step, so I would suggest that you could convert a clock mechanism (gravity) to motor driven with using just one motor.

Stepper Unit Mk 4

Now perfected a single motor stepper unit.

Next stage is to connect to the 2 arm ball lift.


26986191449_b9d4ac33cc_c.jpg

 

 

Edited by Doug72
Embedded video

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39 minutes ago, Sjoemie himself said:

Nice work, clean and simple solution. 

Has this solved the unwanted double-skip?

Yes, can't double skip now, the 4 lobe knob gear prevents it.
Aslo it gives a soft start when bucket wheel starts to rotate to next step.
Have tidied up the structure for knob gear drive.

Now building a similar unit for the two arm ball lift which only requires two steps per rotation.
Hopefully will be able to drive that from the L motor as well.

Edited by Doug72
Added text

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7 hours ago, Sjoemie himself said:

Cool, looking forward to your progress

Update:

L motor is strong enough to run both stepper units just need to determine the right gear ratio for the rotating loading arms.
Has added bonus that the arm rotation slows down as it engages with the knob gear and then speeds up when it dis-engages to give time for ball transfer for loading and discharging. 

Edited by Doug72

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Loading & unloading steeper unit for ball transfer now built.

The rotating arms when they contact with knob gear slow down to transfer balls, then speeds up to next step.
Ball loading and unloading gates to now figure out along with ball runs.

Note: the black 36T gear is only to hold the rotating arms and is not connected to any other gear.

 

 

Edited by Doug72

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Trying to get the two arm ball lift has proved impossible to get it to function as desired in sync. with bucket wheel as it rotates in 8 steps.

After many attempts to progress this build have hit many dead ends and failure.
At the moment I can only conclude it is not going to be successful in replicating the "so called" perpetual motion machine.
Along the way some usefull mechanisms & ideas were found for possible future GBC builds.
 
 
Please note I know perpetual motion is impossible, I was attempting to make a powered version, as the original YouTube video must have had a hidden drive.
Edited by Doug72

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After more thought have continued with this build.
Gondoliers for transfering balls built and an unloading sytem devised.
Top gondoler is shown in the tipping postion.
Next build the ball run back to the bucket wheel. 

Biggest challange will be  loading balls into each gondoller and into each bucket on the bucket wheel at the correct moment.
Some form of control gate will be needed, activated by trips as they rotate.

Update
Now built the return ball run and amazingly the balls roll along and drop into each bucket without any control gate !!!!
Needs a little bit more tweeking.

38890466601_ae7bc267d8_c.jpg

Edited by Doug72

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At last after much trial and tribulations have successfully achieved the gaol of replicating the “Perpetual Motion” device  which must have had a power input hidden somewhere.

My version all driven by one L motor and two stepper units, without any control gates, its all down to timing and fine tuning of various sections along the ball runs.

Spent a lot of time chasing lost orange balls around my study !! 

PS: now to scale it up and use BWE buckets 6145856 !

Heres the video:-
 

 

Edited by Doug72

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Great to see this working ?

The timing seems to require only 4 of the 8 buckets on the main wheel. Is this true to the original? 

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13 hours ago, Boulderer said:

Great to see this working ?

The timing seems to require only 4 of the 8 buckets on the main wheel. Is this true to the original? 

Thanks, your observation is correct, at the moment only 4 buckets are loading.
I think I have a solution which hopefully will not alter the ball run timings and also not require a ball control gate to load the two arm ball lift.

Every time you improve things its been a case of 2 steps forward, 1 step back.

 

Edited by Doug72

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2 hours ago, Sjoemie himself said:

Looking good. I especially like that the ball on the low end of the machine really 'hops' into the bucket.

Must have taken you a few tries to get that just right.

You ar so right, spent ages trying to get things to working smoothly as intended.

Eight buckets now in use.

Solution was to increase the rotation speed of the two arm ball lift and as predicted a lot of tweaking and adjustment to speed was required.
Now faster running at 3rd step on a speed PF controller.

Additional bracing added plus measure to ensure balls do not skip out of the buckets.

A 2:1 step up gear (24/12) was required to run the two arm stepper unit but this resulted in arms rotating the wrong way,  so 1:1 gearing (16/16) was required at the output of the other steeper unit to correct the rotation.
The postioning of the two arm lift is achieved by removing the black 12T double bevel gear, move arm to correct position and replace the gear.

Photos showing extra gearing required & new video.
38096788595_f19c795b1c_z.jpg

24118455677_07a2356972_z.jpg

 

 

Edited by Doug72

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...except now it doesn't work as a perpetual motion machine any more. If it's supposed to be that the balls turn the wheel with their weight, then it makes no sense at all for the wheel to pause for a bit each cycle.

Instead of speeding up the two-arm stepper, you would have been better off making the wheel go twice as fast, and removing every second bucket.

Still, it's a neat bit of kit you've got there!

 

Owen.

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1 hour ago, Captainowie said:

...except now it doesn't work as a perpetual motion machine any more. If it's supposed to be that the balls turn the wheel with their weight, then it makes no sense at all for the wheel to pause for a bit each cycle.

Instead of speeding up the two-arm stepper, you would have been better off making the wheel go twice as fast, and removing every second bucket.

Still, it's a neat bit of kit you've got there!

Thanks for the comments, it has at times been a very frustrating but challanging build and almost gave up.

Its as close as possible to replicate the so call PM machine.

In my version it replicates the action in that the ball rolls along the top ball run, drops into the bucket which then advances one step (1/8th rev)

Getting the motor speed correct is critical to get ball tranfers to work OK in sync.

Surprised that no one has yet asked what the purpose of the white disc with 8 holes and two small wheels on the two arm axle is for !!

Have an idea for a Mark 2 version that will hide all the mechanisms behind a white screen and only use one steeper unit.

PS still hunting for errant orange balls in my study !!

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Having proved that the “Mock Perpetual Motion “ machine can function, I have found it  can be temperamental at times  and get out of sync.

Driving the main bucket wheel via a steeper unit and another steeper unit for the 2 arm ball lift can be jerky and if too runs too fast it upsets the timings for ball transfers.

Now working on an improved Mark 2 version.

Propose that the L motor will drive the two arm ball lift directly via a steeper unit using a 24:1 reduction and a PF speed controller.

The bucket wheel will be hard linked to the 2 arm ball lift via gearing & shafting to rotate bucket wheel using a 4:1 reduction gearing.

i.e. as two arm lift rotates for each half rev. it will rotate the bucket wheel 1 step. (1/8 rev )

The steeper unit will slow down the arms as they pass the ball loading and unloading points.

It should then be easier to adjust the system to keep in everything in sync.

A dummy rope drive and pulleys to be installed to simulate the YouTube video with all the Lego drive mechanisms hidden behind a white panel. 

See mock up of proposed drive system:-
The L motor drive input via reduction gears is at the Red axle connector.
Red beam = 2 arm ball lift.
Yellow beam = 8 step bucket wheel.
Dummy drive shown.
Yellow 15L beam shows where the screen would be to hide the drive mechanism.

25158506368_6820b56892_z.jpg

Edited by Doug72

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finally ordered a bunch of those scoops.. I got the trans-blue clear ones, as they were very cheap...

will be fun to use them in a GBC! :)

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9 hours ago, RohanBeckett said:

finally ordered a bunch of those scoops.. I got the trans-blue clear ones, as they were very cheap...

will be fun to use them in a GBC! :)

Great, look forward to see how you use them.

Got  my white ones from a Lego seller in France.

Doug

Edited by Doug72

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On 12/13/2017 at 6:56 PM, RohanBeckett said:

finally ordered a bunch of those scoops.. I got the trans-blue clear ones, as they were very cheap...

will be fun to use them in a GBC! :)

The trans-blue ones were used in Bionicle sets.  White ones were only in a Mars Mission set if I recall, they would be rarer and pricer than trans-blue.  Good to see everyone making use of those scoops for GBCs.

 

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Yes.. I have to be rather selective with my bricklink orders, being in Australia... no one over here had them in any quantities that I needed... so it required an EU order..

and postage can vary a lot.. some shops are only EU$8... others want over EU$30 for the same size parcel... crazy!

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Found a German seller who has plenty of white visors BUT cost for 12 pce = £3  - Shipping to UK £7.00 !!!

Now started work on a Mark 2 Version having identified failings on the Mark 1 build.

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