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michael.farney
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michael.farney

I never have done the servo thing, but I have been thinking about playing around with this and LOR. I have done some looking on google, but I can't find a good site that teaches about what all these componets are and gives a practical application of each type of servo.

Ultimately, I am looking for either a piston type thing or a pulley type system. I have found the piston type thing called a servo actuator, but it's too short and waay to slow. It goes 0.25 inches a second with no payload?!? I have yet to find anything matching a pulley system. Does a pulley system exist that can be controlled by servo? I am not really looking for pnuematic stuff.

I have a couple of ideas. For one there is a large tree in the front of the yard that is too tall. You wouldn't be able to see any branches from a car if I lit them up due to the way the locations are, but you could store some items up there and drop them into the display -- say angels or stars?

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Greg Young

michael.farney wrote:

I never have done the servo thing, but I have been thinking about playing around with this and LOR. I have done some looking on google, but I can't find a good site that teaches about what all these componets are and gives a practical application of each type of servo.

Ultimately, I am looking for either a piston type thing or a pulley type system. I have found the piston type thing called a servo actuator, but it's too short and waay to slow. It goes 0.25 inches a second with no payload?!? I have yet to find anything matching a pulley system. Does a pulley system exist that can be controlled by servo? I am not really looking for pnuematic stuff.

I have a couple of ideas. For one there is a large tree in the front of the yard that is too tall. You wouldn't be able to see any branches from a car if I lit them up due to the way the locations are, but you could store some items up there and drop them into the display -- say angels or stars?


Hey Mike:

Charles Belcher did that very thing. This was featured on this year's Holiday Lights DVD.

He used an angel that ascended, and descended, and was LOR animated, once it stopped those movements. It was a really neat combined mechanically and electronically animated figure!

He may have a post of it on you tube as well.

Greg
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michael.farney

Yes, I am trying to research what type of products can achieve motion with LOR with reasonable payloads. I don't want to give away all my secrets, but I really wasn't planning on dropping anything out of trees. A piston based solution looks like a bust which is why I was thinking more of a pulley system. Is there a good place to learn about equipment similar to what charles used? Most servos seem so weak they're useless.

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Charles Belcher

Michael,

Answers and comments are within your text below, but first here is a description of my flying angel.

The angel was 1/2" rope light tie wrapped to a remesh wire grid which I bought for 5 bucks at Home Depot. The wire grid has 6" squares and measures 72"x42". My angel filled that size plus I added another 72"x12" piece to accommodate the wings. The whole thing weighed about 8 lbs which I thought was light until I started mocking the rig up in my backyard. I ended up trying one motor I had, bought two more that didn't work and finally bought a huge Dayton from Grainger. This baby was $312.00!!!

Here is the link: http://www.grainger.com/Grainger/wwg/productIndex.shtml?operator=keywordSearch&search_type=keyword&QueryString=1z824b&submit.x=0&submit.y=0

I then bought a 10" fixed bore sheave from Grainger. The model number is a 3X935. This was $27.00. Here is the link.

http://www.grainger.com/Grainger/wwg/productIndex.shtml?L2=Die-Cast&operator=prodIndexRefinementSearch&originalValue=pulley&L1=Pulleys%2C

I too went the servo route at first with no luck. They are great for moving little robots around and noding a head on a deer but not for lifting any weight. Forget about using them to lift and hold any significant weight. The second motor I bought at Grainger. It didn't work and they took it back. I don't remember which one, but after trying and failing with a servo type motor I thought the 30 foot-pound model would work. It would lift the angel but it would not hold the angel in the "up" position without slipping. I don't remember the model, but it was on this page.

http://www.grainger.com/Grainger/wwg/guideBrowseMatches.shtml


Here is my research history on motors. An AC motor can have a brake, but unless you spend $500.00 it will not be reversible. Some are reversible but only if you use the remote with the 10' cord that comes with it. For what we want to do with computer control, that doesn't work so I went the DC motor route.

I had two 12V DC batteries out of an old scooter I wanted use so I narrowed my motor search to 12V DC gear motors. A gear motor is basically a motor with a bunch of torque generated by gears within the motor, which is what I needed to lift and hold the angel. (servos have a lot of torque for their size, but no where near what I needed for this application). Next I had to decide the speed I wanted the angel to move. The piece of music was 12 seconds long and I wanted the angel to descend 20'-28'. Armed with that information, I bought a motor with the correct RPM's and a sheave with a diameter that would take up the right amount of line in the right amount of time.

I used 60lb test SpiderWire which I bought at Wal*Mart for $18.00. I bought 3 rolls because I ended up tearing up the first two with experiments.

I then used a pulley system with a mechanical advantage of 4:1 to further lighten the load on the motor shaft. I placed the motor on the ground in a plastic tub. I cut a hole for the wiring and a slit for the sheave to stick out of the side of the tub about an inch. The angel flew rain or no rain. In fact my whole display played every night regardless of weather (event the dancing Clauses)

I used a dual relay set-up with Radio Shack 120V relays. The model number is 275-218. Here is the link.

http://www.radioshack.com/product/index.jsp?productId=2049722&cp=&sr=1&origkw=relay&kw=relay&parentPage=search


The battery and relay set-up lived in the tub. One channel of LOR ran to the first relay and when activated was the "up". I jumped out of the first relay to the second and another channel of LOR ran to that relay for the "down".

After about 3 weeks of trial and error it worked. Lucky for me, I did all of this in August.

Here are a couple of more notes.

1) I ran two lines of Spider-Wire down each side of the remesh grid. They were tied to the tree limb above and anchored into the ground. These served as a "guide" only so the angel would not swing around in the wind.
2)Using a battery worked OK, but I had to charge one while the other was in duty and switch them out every other night. If I didn't, as the voltage dropped, the speed of the motor slowed. In a DC motor the RPM's developed is proportional to the voltage supply. So basically, if the battery was only 10 volts (because I forgot to change it) then the angel would not come all of the way to the harp.
3) By only needing 4 feet of movement, your needs will be simplified as long as the timing doesn't have to be on the money. Mine did because it was a movement within a song. BUT, most importantly the whole deal is ALL ABOUT "foot-pounds" or "inch-pounds". Take your time and research and understand this concept. It will make or break the deal.

That's all I can think of for now. Hope it helps. Fireworks comments/answers are below in your text.

Charles,

I am looking at doing servos with LOR this year, and I wanted to ask if you have any tips or good places to buy. I was originally looking at a servo actuator, but it looks like that won’t quite fit the application. I was then thinking a pulley system, but google has not turned up much. I only need about 4 feet of motion, but I don’t see anything that will accomplish this. Did you find a pulley system that is servo controlled? I saw your video of the angel which was awesome.

I am hoping you have some tips or sites that may help me out learning about servos with LOR. I can find plenty of small servos, but nothing that can handle a reason payload for a Christmas display. Where did you find something that could handle the weight of your angel prop?

I also love the fireworks. I might do a similar setup for a Disney piece this year, although I have nowhere to put them unless they fire from the ground and the burst is on the roof. Yours seems quite a bit higher – I assume they were tree mounted. Is the light storm worth the cost? I think it will beat out building custom boards for fireworks. After all, I have several Disney characters I have to make for this year. I also remember you mentioned you used colored strobes. Did you pick those up from action? Their colored strobes seem to be an unusual base size. I’m not sure what fits them.


My "shafts" of fireworks were mounted on the peak of my rooftop. The Storms I and II's were mounted higher up the trees. The red and yellow Action Lighting strobes were also in the trees and they screwed into a regular C9 strand. I live in a two story house which has about a 40' roof peak and the pecan trees in my front yard are way higher than that, so I had alot to work with. The pro's and con's are as follows:

1) Height is good for the effect but I had to rent a 60' boom lift to do it.
2) Height is good for effect but I couldn't get far enough across the street to video the entire scene

Finally, I am attempting 3500 channels of DMX controlled fixtures and devices in my 2008 Christmas Light Display. Part of this system is a LED tube grid which will do 16 million colors but with the aid of some high powered software (not LOR) it will allow me to pixel map the LED grid for video reproduction as well and be called up on a DMX channel.

...and I thought the flying angel was hard. :) Please feel free to contact me as often as you like.

Charles

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