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Subject: 
(no subject)
Newsgroups: 
lugnet.technic
Date: 
Wed, 25 Feb 2004 23:40:15 GMT
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i have just posted pics of my rolling ball clock on brickshelf:

http://www.brickshelf.com/cgi-bin/gallery.cgi?f=73767

here is an explanation:


This clock is based on the Arrow Handicraft Deluxe Rolling Ball Clock that
was popular in the 80's.

To tell the time read the hour from the 3rd row of balls.  For the minutes
add the 1st and 2nd row of balls together.
On the first row 1 ball = 1 minute.  On the second row 1 ball = 5 minutes.

My friend Chris Scheuerman asked me if i had ever seen a rolling ball clock
before.  He told me that he just got one and that i should come take a look
at it and try to make one out of LEGO.  I never did go over and look at his
clock.  In fact my clock was built strictly from pictures found on the
web.  I have never seen one of these clocks in person.  I spent about 2
months making this moc and 1 month fine tuning and debugging.

The ball holding, balancing, tilting, and logic was simple to make.  It did
take a few bricklink orders to get enough ribbed tubbing and soccer
balls.  The lift mechanism is what stumped me.  I thought about it for
about a month before i came up with a design that i thought would work.  It
still took a lot of tweaking to get it to work correctly.  The real clock
has a rotating arm that lifts the balls up to the top.  I was originally
going to copy the same rotating arm, but i would have needed a very long
arm because of the height of the ball logic.  So i went with the chain lift
mechanism.  It turned out very well.

During debugging improvements were made like adding extra guard rails so
all the balls would return to the ball holder and not the ground.  One
problem that i have not solved yet is the lift mechanism is not 100%
accurate.  Very rarely, 2 balls are lifted at the same time or no balls are
lifted at all.  But i think that the no lifts and the 2 ball lifts even
then selves out because after running for 3 days at Brickfest PDX it was
only about 1 or 2 minutes off.

I think i will keep this one together for a while.  It is kind of
mesmerizing watching the balls go up and roll around.


Movies of the clock in action can be found here:
http://klickitat.fial.com/bob/rollingballclock/


Bob Kojima
bob@fial.com

http://www.bong69.com
http://www.partscatalog.da.ru





Bob Kojima
ko@fial.com

Fial Incorporated
Telecom Monitoring Solutions
4343 SW Corbett Ave
Portland, OR  97239
503.227.7083
http://www.fial.com

   
         
     
Subject: 
Re: (no subject)
Newsgroups: 
lugnet.technic
Date: 
Thu, 26 Feb 2004 09:09:42 GMT
Viewed: 
4338 times
  

http://www.brickshelf.com/cgi-bin/gallery.cgi?f=73767
Great clock.
And, most inventive use of Soccer Balls I have ever seen :)

   
         
     
Subject: 
Re: Rolling ball clock
Newsgroups: 
lugnet.technic
Date: 
Thu, 26 Feb 2004 12:58:13 GMT
Viewed: 
4324 times
  

Hey Bob!

That's a really neat clock!

Had never heard about it previously! Nice rendition in LEGO!

Looks simple enough, but I quess getting the balls to roll safely is a trick in
itself.

So what basically determines the speed/accuracy of the clock is the speed of the
conveyor?

--
Best regards,
/Tobbe
<http://www.lotek.nu>
(remove SPAM when e-mailing)

   
         
     
Subject: 
Re: Rolling ball clock
Newsgroups: 
lugnet.technic
Date: 
Thu, 26 Feb 2004 15:36:29 GMT
Viewed: 
4400 times
  


Had never heard about it previously! Nice rendition in LEGO!

here is the link to the pictures that i used to build the clock:

http://www.stuartsinger.com/ballclock.htm


Looks simple enough, but I quess getting the balls to roll safely is a
trick in
itself.
yeah,  the balls get rolling pretty fast and don't want to stay on track
around the curves.



So what basically determines the speed/accuracy of the clock is the speed
of the
conveyor?
yes, the lift is suppose to bring up 1 soccer ball per minute.  i use a
train controller to regulate the speed of the lift motor.

bob







Bob Kojima
ko@fial.com

Fial Incorporated
Telecom Monitoring Solutions
4343 SW Corbett Ave
Portland, OR  97239
503.227.7083
http://www.fial.com

   
         
     
Subject: 
Re: (no subject)
Newsgroups: 
lugnet.technic
Date: 
Thu, 26 Feb 2004 16:05:52 GMT
Viewed: 
4570 times
  

In lugnet.technic, Bob Kojima wrote:
i have just posted pics of my rolling ball clock on brickshelf:

http://www.brickshelf.com/cgi-bin/gallery.cgi?f=73767

Wow!  Thgis is some king of hypnose, isn't it?  I mean, I can't keep my eyes of
the rolling balls!  I have about 100 soccer balls at home and I have some good
ideas to use them, but none as cool as this!  I want one too!

Very well crafted.  I like the color scheme too, even though in a MOC of that
kind, people don't usually look at the esthetics, but at the mecanism, you
really did a good job making it look fabulous!

It would be awesome if you could post instructions.  If you don't use CAD (like
me), you could smply take it apart one step at a time, take pictures of every
step and publish these pics in the inverse order.  I know I'd try to build it!

Something tells me that ribbed hoses and soccer balls will be more popular on BL
if you post instructions!

Terry
www.minifigville.com

   
         
     
Subject: 
Re: (no subject)
Newsgroups: 
lugnet.technic
Date: 
Thu, 26 Feb 2004 17:13:44 GMT
Viewed: 
4444 times
  

At 04:05 PM 2/26/2004 +0000, you wrote:
In lugnet.technic, Bob Kojima wrote:
i have just posted pics of my rolling ball clock on brickshelf:

http://www.brickshelf.com/cgi-bin/gallery.cgi?f=73767

Wow!  Thgis is some king of hypnose, isn't it?  I mean, I can't keep my
eyes of
the rolling balls!  I have about 100 soccer balls at home and I have some good
ideas to use them, but none as cool as this!  I want one too!

i know i could stare at it for hours.  at one time i had 4 ball lifts on
the chain so that it would run 4 times as fast.  i'm not patient enough to
wait a minute for each ball to be lifted.


Very well crafted.  I like the color scheme too, even though in a MOC of that
kind, people don't usually look at the esthetics, but at the mecanism, you
really did a good job making it look fabulous!

thank you,  i tried to make it as simple as possible with the least amount
of parts.  my goal was to not let the frame work get in the way of viewing
the balls.  my fist intent was to make the lift mechanism be in the back of
the moc.  but when i finished i thought that the lift mechanism was just as
interesting to watch.  so i turned it around and the back became the front.


It would be awesome if you could post instructions.  If you don't use CAD
(like
me), you could smply take it apart one step at a time, take pictures of every
step and publish these pics in the inverse order.  I know I'd try to build it!

looks like i'm going to have to learn how to use ldraw to model this.  i'm
going to have to learn how to model the ribbed tube too.  i think it would
be very cool to see other renditions of the clock and see what improvements
can be made.


Something tells me that ribbed hoses and soccer balls will be more popular
on BL
if you post instructions!

i guess i better stock up on ribbed tube cause i would like to make a
marble machine next.  one where the balls can just roll around all over on
multiple paths.  finally a functional use for ribber tubbing.

bob






Bob Kojima
ko@fial.com

Fial Incorporated
Telecom Monitoring Solutions
4343 SW Corbett Ave
Portland, OR  97239
503.227.7083
http://www.fial.com

   
         
     
Subject: 
Re: (no subject)
Newsgroups: 
lugnet.technic
Date: 
Fri, 27 Feb 2004 18:25:07 GMT
Viewed: 
4324 times
  

 [ chnic, Bob Kojima wrote:
i have just posted pics of my rolling ball clock on brickshelf:

http://www.brickshelf.com/cgi-bin/gallery.cgi?f=73767

here is an explanation:


This clock is based on the Arrow Handicraft Deluxe Rolling Ball Clock that
was popular in the 80's.

*snip*

During debugging improvements were made like adding extra guard rails so
all the balls would return to the ball holder and not the ground.  One
problem that i have not solved yet is the lift mechanism is not 100%
accurate.  Very rarely, 2 balls are lifted at the same time or no balls are
lifted at all.  But i think that the no lifts and the 2 ball lifts even
then selves out because after running for 3 days at Brickfest PDX it was
only about 1 or 2 minutes off.


Oh, I'm going to sheepishly chime in here - I 'set' the clock a couple of times
during the weekend.  I was so completely amazed and fascinated with it I just
couldn't bear for it to not be accurate!!  But once it was set, it seemed to be
accurate to within 1 or 2 minutes an hour.  Have you considered adding an RCX
for even better time accuracy?

Bob, this thing is just fantastic, and it was by far my favorite MOC at
Brickfest PDX.  Congrats on a great job!

Now, I hope you don't mind if I steal *ahem* "borrow" your lift design for a
project we've been kicking around (no soccer pun intended!)...  ;-)

JohnG, GMLTC

   
         
     
Subject: 
Re: (no subject)
Newsgroups: 
lugnet.technic
Date: 
Fri, 27 Feb 2004 19:29:42 GMT
Viewed: 
4262 times
  


Oh, I'm going to sheepishly chime in here - I 'set' the clock a couple of
times
during the weekend.  I was so completely amazed and fascinated with it I just
couldn't bear for it to not be accurate!!  But once it was set, it seemed
to be
accurate to within 1 or 2 minutes an hour.  Have you considered adding an RCX
for even better time accuracy?

that's why it was always the right time.  pdx was the first time i let it
just run for hours so i was not really sure of how accurate it would be.



Now, I hope you don't mind if I steal *ahem* "borrow" your lift design for a
project we've been kicking around (no soccer pun intended!)...  ;-)

borrow what you want.  i borrow ideas all the time.  i'm glad you liked it!

bob






Bob Kojima
ko@fial.com

Fial Incorporated
Telecom Monitoring Solutions
4343 SW Corbett Ave
Portland, OR  97239
503.227.7083
http://www.fial.com

   
         
   
Subject: 
Re: Ball Clock (was: no subject)
Newsgroups: 
lugnet.technic
Date: 
Sat, 28 Feb 2004 00:51:35 GMT
Viewed: 
4497 times
  

In lugnet.technic, Bob Kojima wrote:
i have just posted pics of my rolling ball clock on brickshelf:

http://www.brickshelf.com/cgi-bin/gallery.cgi?f=73767

Saw this at Brickfest PDX. It is indeed quite impressive in person.

< snip >

One
problem that i have not solved yet is the lift mechanism is not 100%
accurate.  Very rarely, 2 balls are lifted at the same time or no balls are
lifted at all.  But i think that the no lifts and the 2 ball lifts even
then selves out because after running for 3 days at Brickfest PDX it was
only about 1 or 2 minutes off.

This is a problem you will probably not solve as long as there is a bin of balls
for the conveyor to draw from. The Seattle robotics guys will tell you that
getting soccer/basketballs to feed reliably from a bin is a non-trivial task.

Having built the original model in the 80s, I can tell you how it was solved in
the prototype. The balls must never enter a dump bin. By eliminating the dump
bin at the end of the return track, and lengthening the return track so that it
can accomodate the maximum number of balls (let's see, that would be 11+11+5=27
at 1:00), you should find that other balls do not interfere with the pickup
mechanism, and it should pick up one ball reliably each time.

You can test this theory by adding multiple pickup mechanisms (so you don't have
to wait 60 seconds per ball), then manually feed one ball at a time into the
bin. If your mechanism design can reliably pick up one ball every time, then you
know that eliminating the bin will work.

Hope that helps!

Great job. Ditto on every positive comment made in this thread.

Rick Clark

 

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