Date   
Re: Random motion

 

Greetings...
This is a wonderful little random unit.  Good job.  It looks like you made the gear teeth out of cardboard ribbons?
Thanks for sharing.
Cheers
-Jim Coffee-

On Thu, 9 Jan 2020 at 13:27, <catilaporte@...> wrote:
Wow! I just spend the day  building it to test my gears, all made of cardboard , somewhat flimsy but working .
https://www.facebook.com/photo.php?fbid=10157935732058390&set=a.61241608389&type=3&theater
(I am in my week 4 in automata learning )

Re: Random motion

catilaporte@...
 

Wow! I just spend the day  building it to test my gears, all made of cardboard , somewhat flimsy but working .
https://www.facebook.com/photo.php?fbid=10157935732058390&set=a.61241608389&type=3&theater
(I am in my week 4 in automata learning )

What's On My Bench: Connecting the links

 

I'm in the process of connecting the cams to the parts of the automata that need motion.
I've been using  polyurethane belting for about four years now.  I've been using it only to "drive" things.   I source it from McMaster-Carr.  As a result of using it I've become more familiar with it.  It's flexible, tough, a tiny bit elastic  (negligible in short lengths).  One of the things that I've noticed is that I've never had a joint fail.  The tubing is cut, and then joined with a little aluminum fitting that has ridges on it.  I've never had one come apart.
So as I was creating linkages between cams and parts of the automata that I'm working on I realized that I could use this tubing as links.  A #4 screw screws into the hollow core of the tubing...and essentially won't come out.  I've got it in two colors...yellow (which I am using inside the drive frame), and clear (which I am using outside the drive frame).
I've attached a couple of images to show you how it works.  So far I'm pleased with how this is going.
I look forward to seeing what on your workbench.
Cheers
-Jim Coffee-
one of the Automata Group Moderators
I create automata near San Diego, California

IMG_20200108_195745-1000.jpg
IMG_20200108_195803-1000.jpg

Re: What's on my bench: Removable CamPak

Mike
 

Wonderful idea Jim. Depending on the design of the automata a removable campak could be swapped out with other campaks to provide a different effect. The writing automata come to mind.
--
Looking forward to hearing about your automata adventures!


Mike

Wooden Curiosities

What's on my bench: Removable CamPak

 

Greetings all...
The automata that I am currently working on calls for 6 cams.  As I contemplated the build I realized that if I "built these things in" that it would be a difficult build...and that maintenance (should there be any) would be difficult.  So I decided that I wanted the campak to be easily removable.  For size reference...the cams are 5" diameter, 3/16 inch baltic birch ply.
The first image shows the campak installed...and the second image shows the campak removed.  Removal takes 1 minute at the most.
The cam followers will hang from the shaft that you see above the campak.
The next steps in this build will be to remove five of the six cams...and then create the follower and linkage and then cut the sixth cam.  When done with the 6th cam...repeat for the five remaining cams.
When completed it should all work.  I hope so...I've never done this before.
Cheers
-Jim Coffee-
one of the Automata Group Moderators
I create automata near San Diego, California

IMG_20200102_181505-1000.jpg
IMG_20200102_181348-1000.jpg

Re: Tiny Insect Contains the Only Mechanical Gears Ever Found in Nature

 

This is really interesting.
Wouldn't you love to own and know how to operate an electron microscope?
Cheers
-Jim-

On Thu, 2 Jan 2020 at 12:12, Randy <rglissmann@...> wrote:
I thought this was interesting. https://www.thevintagenews.com/2020/01/02/mechanical-insect/


-Randy

Tiny Insect Contains the Only Mechanical Gears Ever Found in Nature

Randy
 

Re: What's On My Bench - Colorado Christmas

Gus
 

Nice Mike,

One way to finance some new toys ........

Gus

Re: Happy New Year

Gus
 

All best to you too Mario, 
Gus

Re: Happy New Year

Gus
 

Wish you the same Mike,

Gus

Re: Cycle speed and realism

Gus
 

It depends on many factors, doesn't it ?
How good is the element being manipulated, eg a head turn mechanics high tolerance, or sloppy ? Does it jerk because the mechanics aren't well machined/sanded/lubricated ? Unless that is what is wanted of course. Irrespective whether a fast or slow turn is wanted, the execution is crucial, otherwise it fails. Are multiple movements taking place, each one a different speed, as one would expect, eg a waving arm can imply something simply by how fast or slow it moves, and the same figure turning from the waist in conjunction might execute that quite fast, presenting a complete emotion. 
My approach is focused around the story I want to tell, without using words. I don't decide at the beginning how fast or slow it needs to be, that develops as the work progresses.  Often reworking cams, gears etc if it seems the story has no flow, fails to engage, or, as you put it, “Yawn”.
Good expression that ! 
The element of surprise is what I seek. Be that  fast or slow, matters not much to me.

Gus

Re: Cycle speed and realism

 

This is an interesting question that at least to me involves some pretty complicated stuff.
First, let me say "To each h/her own".  
Here is how I do it for my own automata:
  • I know that I want both a hand crank and a motor.
  • I consider a comfortable crank speed to be approx 50-60 rpm.  Note that I am defining the crank speed by operator comfort.
    • Thus I use gear motors that are 50 rpm.
  • The speed of the automata action is very important.  Prior to creating my drive components I visualize how fast I think things should go.  I focus pretty carefully on this.  It's important.  
  • I believe that 'slower' is desirable more often than 'faster'. Not too slow is the trick.
  • I then create the drivetrain to meet the requirements of both ends.
    • The automata that I am creating right now needs three speeds:
      • 50 rpm for crank/motor input
      • 150 rpm for pulsing
        • I accomplish this by having three nodes on the 50 rpm shaft.
      • 1 rpm for driving the CamPak.
        • I accomplish this with a reduction train of pulleys and poly belting.  It's very smooth and quiet (and powerful).
Bottom line...the speed of things is very critical and important.  Wrong speeds make an automata not credible.  Correct speeds make it delightful and a pleasure to operate/watch.

I look forward to reading other comments.  Good question.

Cheers
-Jim Coffee-
one of the Automata Group Moderators
I create automata near San Diego, California



On Wed, 1 Jan 2020 at 14:21, V Bass <vrbass@...> wrote:
Over the years, I've seen a lot of automata and videos of automata and a thought has been slowly forming about what makes a piece interesting and engaging. And it comes down to speed.

To my eye, an automaton engages the viewer when the movement seems natural, and a lot of the appearance of naturalness depends upon timing. Imagine we're looking at an automaton with a couple of kids on a seesaw. The cycle time of this piece is 10 seconds - it takes five seconds for one end to rise, five more to go back down. Visualize that by moving your hands up and down and counting five seconds up, five down. 

Yawn. Have you ever seen a couple of kids go at that pace? Picture it in your mind and figure how long you think real pair of kids would take - 3 seconds for calm kids, 1 for hyperactive kids?

How can we control this? Thinking out loud here, you'd have to work from the final movement backwards, looking at cam profiles, lever ratios, gear train ratios, input (crank/motor) speed, adjusting all accordingly. It's a complicated chain of actions, but if the design doesn't take the end movement speed into account, it can end up looking like the whole mechanism has been soaking in syrup when it operates.

Oddly, I can't recall seeing an automaton that seemed unrealistic because the movements were exageratedly too fast.

What are your processes for getting realistic movement speeds in your pieces? Do you work backwards as above, forwards from the desired crank or motor speed, or set the two end speeds and make the middle bits fit?

Re: Cycle speed and realism

Paul E Giles Jr
 

I'm a both ends towards the middle guy. I exclusively use cranks because I love to watch the grandkids work the device. Kids being kids I immediately reduce the shaft speed because their excitement means lots of rpm's. I also try to use a couple of elements and that means different speeds. And yes, I often slow down the speed only to increase it later for an object. 

Cycle speed and realism

V Bass
 

Over the years, I've seen a lot of automata and videos of automata and a thought has been slowly forming about what makes a piece interesting and engaging. And it comes down to speed.

To my eye, an automaton engages the viewer when the movement seems natural, and a lot of the appearance of naturalness depends upon timing. Imagine we're looking at an automaton with a couple of kids on a seesaw. The cycle time of this piece is 10 seconds - it takes five seconds for one end to rise, five more to go back down. Visualize that by moving your hands up and down and counting five seconds up, five down. 

Yawn. Have you ever seen a couple of kids go at that pace? Picture it in your mind and figure how long you think real pair of kids would take - 3 seconds for calm kids, 1 for hyperactive kids?

How can we control this? Thinking out loud here, you'd have to work from the final movement backwards, looking at cam profiles, lever ratios, gear train ratios, input (crank/motor) speed, adjusting all accordingly. It's a complicated chain of actions, but if the design doesn't take the end movement speed into account, it can end up looking like the whole mechanism has been soaking in syrup when it operates.

Oddly, I can't recall seeing an automaton that seemed unrealistic because the movements were exageratedly too fast.

What are your processes for getting realistic movement speeds in your pieces? Do you work backwards as above, forwards from the desired crank or motor speed, or set the two end speeds and make the middle bits fit?

Re: Happy New Year

Mario Núñez
 

Happy New Year one and all!

Mario

Re: Happy New Year

 

Thanks Mike...
Yes...Happy New Year to all.
Thanks for participating in this forum...thanks for your creativity and efforts.
A new Automata Magazine is due tomorrow.  Looking forward to it!
Cheers
-Jim Coffee

On Tue, 31 Dec 2019 at 08:58, Mike <smc5910@...> wrote:
I hope all of your 2020's are filled with lots of great automata!


Mike

Wooden Curiosities

Happy New Year

Mike
 

I hope all of your 2020's are filled with lots of great automata!


Mike

Wooden Curiosities

Re: Mixing Media Within the Mechanics

Mike
 

Yes, thanks everyone. :)
--
Looking forward to hearing about your automata adventures!


Mike

Wooden Curiosities

Re: What's On My Bench - Colorado Christmas

Mike
 

The "Santa Claus is Coming to Town" automata was quite popular. I got orders for four more. :)

It's good for the ego but bad for creativity. I find it hard to replicate pieces as it doesn't hold my interest as well.
--
Looking forward to hearing about your automata adventures!


Mike

Wooden Curiosities

Re: What's On My Bench - Colorado Christmas

 

I forgot to mention the music box...another nice and appropriate detail.
--
-Jim Coffee-
creating automata near San Diego, California
one of the group moderators
JamesCoffee.com