Make Your Own Rainbow POV Lamp! From Literally Junk!

by Lets Innovate in Circuits > LEDs

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Make Your Own Rainbow POV Lamp! From Literally Junk!

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Hello Guys!

Welcome back to another instructables where I will show you how to build a completely customizable RGB POV Lamp from junk parts and a handful of electronics.

I have 2 videos on the topic. I suggest watching them, they will give you clear guidance to make the project. You can choose between a voice over video or a music montage. Alternatively you can go through the steps below.

Voice - over:

Music:

While you are at it , please also consider liking, sharing and subscribing. I will love some support on my channel.

My channel: https://www.youtube.com/channel/UCmG6wEl-PEJAhn5C3...

Also vote for my project in the rainbow contest if you like my work.

Thankyou.

Supplies

Supplies are not that much.

Most of it is junk, including PVC pipes, wood, shoe boxes, cardboard all that stuff.

Sticking materials used are hot glue, double sided tape, and electrical tape.

You will need a handful of electronic components:

Arduino nano

7 common cathode RGB LEDs

wires

Soldering Iron

Solder

5 - 12v battery. I used a 9v one with a battery clip.

Choosing a Base.

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I went with this metallic CD drive casing, I had laying around. Dont worry if you dont have one lying around.

You can just use a shoe box made out of tough cardboard.

Any kind of box which is strong, tough and sturdy will work. It just has to be big enough.

Selecting a Motor and the Shaft

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I got my DC motor from an RC car or maybe a small fan. I don't remember correctly, but such motors are everywhere and you can easily recycle them from old electronics.

Or you can buy proper motor. Make sure it is rated atleast 900 RPM. This is necessary for the illusion to work.

You can also see that I have attached sort of an adapter to it. This is made out of cogs. Cogs are everywhere, old RC cars, fans etc. I got this adapter for the shaft to sit in. But if you are already using a straw you can just glue it and it will work fine.

The shaft as I tell in my video can be rolled cardboard, wooden rod, straw filled in with cardboard anything that you find ease with.

If you have a rod like mine, then a straw between the rotor and shaft to hold them and fixing them with glue will also work as I have shown in the picture.

Also solder long wires to your DC motor. If you use a metallic casing like mine then covering the contacts is a must.

Mounting the Motor

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Most motors already come with mounting holes and you can easily mount them in with bolts and nuts.

Unfortunately mine was not like that and you could also have such a motor.

For mounting my DC motor, I simply measured it's diameter, made a fitting circle on the top of the casing and cut it out. Metal is hard to cut and I also cut my finger in the process. Just be careful around the sharp edges and handle cutting tools with care. Wear protective gear and parental help is advised.

After making the hole, make sure the motor goes in. I permanently fix my motor with some glue later.

Making the Right Structure to Avoid Stability Issues. (Part 1: Stability From the Sides)

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As you can see, my general structure was supposed to be packed from all sides. Stability is a key issue when creating these things and cannot be overlooked.

The general structure contains, smaller wood panels on either side of the casing to hold the PVC pipes and to provide a workable space for the electronics. The PVC pipes balance out weight and also hold the top panel which also makes the structure stable. The top panel also houses a small cylinder into which the shaft will go so that when the motor spins, the shaft does not dis balance and go crazy due to the higher center of gravity.

This step deals with mounting the PVC pipes.

First step, you need to get some PVC pipes. I found my PVC pipes in the backyard. They are very cheap anyway. Make sure you have enough length of 2 PVC pipes(depends on how tall you want your lamp to be, donot make it too tall or it will get very unstable due to the higher center of gravity, also you will need to cut the excess according to the length of your shaft, leaving them a few centimeters more in length than the shaft. {The PVC pipes should have a length such that the top panel does not touch the shaft})

Now to mount the PVC pipes, I got 2 small thin wood pieces each 5.3 cm squares. I then measured the diameter of the PVC and made holes according to the measured diameter on the wood. The PVC pipes should snugly fit in. When final-ling everything you might have to hot glue the PVC pipes so that they don't displace.

Lastly I use simple bolts and nuts and fix the wood panels on either side of the casing. Make sure the panels align with the center and that you have a good amount of space on both sides from the motor to the PVC pipes, otherwise you will have difficulties with the rotating structure mounting the electronics. I have 9cm of space from the center to both PVC pipes.

Making the Right Structure to Avoid Stability Issues (Part 2: the Top Panel and Another Issue)

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Now comes the part to mount the top panel. My top panel was a wood piece 25 cm long, 5 cm wide , and 1.5 cm thick. I also found this in the junk in my backyard. Tough cardboard will also work.

The top panel also holds a cylinder to control the shaft as told before. You can make it out of cardboard. I use a small plastic cylinder. I got it when I had previously bought some copper wire. I attach the cylinder on the top panel with double sided tape where the shaft reached the top panel. The shaft does not touch the top panel but is blocked by the cylinder on all sides from dis balancing.

The top panel needs to be fixed to the PVC pipes. You can use glue for this step or create circular indentations according to the diameter of the PVC pipes in the top panel and then secure them together.

Another issue was that the bolts and nuts used to attach the smaller wood panels on the bottom made the structure unstable. So you will need to add some elevation. I use useless wood pieces with double sided tape. You can use erasers or rubber pads.

The Structure to Hold the Electronics and RGB LEDs

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You can use a rim of a useless bucket if you have one which has a diameter which coincides with the workable space you have between the PVCs. I didn't have one so I just used cardboard strips. I went with the rectangular shape shown. It is easier to mount the electronics on it and it spins fine.

My RGB LEDs were 7 common cathode ones. I suggest common cathode ones as they are easier to control.

To mount them I simply created a layout on one side of the rectangular strip and cut the holes for the LEDs. The LEDs snugly fit in as shown. The arduino nano will obviously go on the opposite side of the LEDs on the strip.

The Schematic and Soldering

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I have provided the schematic of my circuit. It's very simple. The crosses show that the wires don't connect.

Basically, the red pins of all LEDs are connected together and then to digital pin 9 (PWM pin). Similarly for the other colours blue and green, the legs of the LEDs are soldered together and then connected to digital pins 10 and 11 (also PWM) respectively. The ground pins of all LEDs are soldered seperatley to the digital pins 2 to 8.

The power supply I use is a 9v battery. The nano works with 6 - 12v. The 9v battery lasts longer so I used it. Your battery should not make the structure too heavy.

I suggest you use thin flexible wires for the soldering. The battery will have to be placed in the center on the shaft like I did with mine. I didn't use a switch because the battery clip I used acted like one.

Once you are done with the rotating structure, use glue and tape to tidy the wiring up and securing everything. Make sure it does not get too heavy.

The Arduino Codes

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I have provided some example codes. Take a look at them. The concept is actually multiplexing. You can check out this video I have on the topic:

Basically, you turn on one LED at a time but you do it very very fast that your eyes don't catch it.

All Done! Have FUN!

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Take your lamp to some dark place to properly visualize it's awesomeness. Power up the arduino and the motor and enjoy the light show.

You can create all sorts of patters and colours in this lamp. It is completely customizable.

One more thing I would like to point out is that the camera does alot of injustice to the project. As you can see in my pictures and video the camera never catches a complete a full ring. It's because of the camera's frame rate. This problem does not happen with the naked eye.

Lastly I would like to say that I hope you enjoyed this project. If you have any queries you can look into my videos for more details or ask me by commenting. Thank You.