Polar table design

You guys are all a few floors above me in corner offices with killer views but you’re definitely making me curious about what’s inside this thing. We’ve had it for a couple of years. I think I ordered it off of ThinkGeek. It’s the one reason I need to wait for the right moment in life to surprise the wife with a sand art coffee table :wink:

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Through the magic of the Internet:

(Spoiler alert!!)

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How about an upside down Delta machine? Here is a calculator for Delta sizes. http://www.thinkyhead.com/_delta/

That video looks like a really cool method for a sand table if you come up with a design for that.

That would be a big box, and another motor. It would be pretty for the firmware though. The other interesting thing is that you could actually move the magnet away from the surface. You could even have it follow a non-flat surface… I’m not sure if that’s useful but…

I like the next video this guy has. He’s creating light patterns without the sand:

Well that saves the questioning by the family. “What are you doing to it dad?!”

Hahaa…

That’s pretty simple. Neato. Kinda like a spirograph… Thanks for digging that up to indulge me. my Wifi in the basement office isn’t like yours on the executive floors…

Don’t believe everything you hear… It’s actually slower to push all those bits and bytes up to the rarefied upper stories. Down in the basement gravity works to your advantage.

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I found some pretty good math for spirographs. I should be able to add stuff like this to sandify without too much trouble.

(hijacking this thread for more sandify stuff, but, oh well).

After thinking about this, these movements reminded me of the Trammel of Archimedes. That movement by itself will not give you want you want, but might be something to consider to start with. https://en.wikipedia.org/wiki/Trammel_of_Archimedes

I remixed someone’s thingiverse design to use only plastic parts if you want to play with the idea. https://www.thingiverse.com/thing:2927475

Did you ever see this video of software creating gears based on movment.

gzumwalt on thingiverse had it linked on this build he did. https://www.thingiverse.com/thing:1212665

Gzumwalt has some pretty cool designs & challenging to print & put together.

Oval table! Since the two axes are linked, you can’t really adjust the radius of the endpoint without changing the length of that linkage, but you could put the linear axis on the arm, and instead of rotating it on a circle, you could rotate it along an oval. That might be pretty fun. I don’t know how you would get the power to the linear axis.

The most terrifying part about that is that it’s from Disney. They have their hands in some strange honeypots… But otherwise, that is some really cool software. Instead of the “open loop” way of choosing the size of the gears and lengths of the rods, you’re able to go backwards, a bit and choose the gears and rods from a pattern. The method for determining that is a good algorithm for a lot of problems too. Just put in a huge number of input and record their outputs. Compare a desired output to your database of input/output pairs, and find the closest one. Then search around the space of the closest match for inputs that match even better. Add in some simulated annealing to avoid local minimums, and you’ve got a non-linear system solver! I’ve used something similar to this to determine a camera calibration on some very inexpensive (high distortion) cameras.

You just need more wifis!

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I have all mine named the same, so my phone doesn’t try to hold on to the last one when I change rooms. There the one in the server room (nee pantry), the one in the master bedroom, the one in the laundry room (feeds the garage), the one in the garage, the one in the living room and the one in the upstairs bedroom. No WiFi shadows around my place! :slight_smile:

[quote="billsey,post:52,topic:8747"] I have all mine named the same, so my phone doesn’t try to hold on to the last one when I change rooms. There the one in the server room (nee pantry), the one in the master bedroom, the one in the laundry room (feeds the garage), the one in the garage, the one in the living room and the one in the upstairs bedroom. No WiFi shadows around my place! ?

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That’s just the device names. There are 4 separate ssids. One home, one for the barn, a guest, and the two devices named chromecast just have a separate chromecast wifi. Barn lives by itself, home and guest are separate vlans on the ac devices.

Can you cast to the chromecast from the other networks? I tried to do that but couldn’t figure out the rules to let the ahavi stuff through.

Yea, the chromecast network is on the same vlan as the house wifi, just uses its own radios. This way they’re not fighting for wifi bandwidth, and I can still use my old hardware after the ac update.

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Darn. I have a wifi that I use for all my IoT stuff and then I have another router inside that net for my computers and phone. I could do it with vlans, but I have the extra router. But if you’re connected to the inside-most router, I can’t get avahi stuff to resolve to the IoT stuff. So I end up using that anyway, which doesn’t really help. I feel like the answer is something about the avahi server in the router, but I can’t figure it out.

And also, something about a polar table…

Polar table… Isn’t that something Kelly carves?

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Nah. That’s just his work surface.

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So does anyone have any experience with a polar table? I had assumed I could just use Marlin and select polar for machine type and away we go, but now I’m not sure. I’m going to research it, but thought I would ask all you wifi experts if you already knew of a good starting point.

I posted a video of my sand table running through 24 hours of designs. A lot of them are converted Sisyphus designs.

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