Plane in a Globe - Hacking a PIR Sensor to Do Your Bidding

Hi All.

Ever had an idea pop into your head and you can't stop thinking about it?  Well my idea was to have a tiny plane spinning inside a light bulb, activated by a sensor!  Yes I know - not much of an idea but there it is. 

First I prowled the internet trying to find the right type of sensor and I came across the PIR sensor.  These are really ingenious and work by sensing infrared radiation. Everything emits some low level radiation, and the hotter something is, the more radiation is emitted.

I purchased a couple from Ebay and started to try and hack them by using a relay.  After much frustration I decided to give this up and try another avenue.  I found a heap of articles using arduino but I wanted to keep it simple.  In the end I decided to use a 8 LED Light PIR Motion Sensor .  The sensor had everything I needed to enable me to hack away with ease.

So here's my idea come to life - kind of.  After much breaking of light bulbs I finally managed to complete the project.




Hope you Enjoy.

Parts List

1. 3v geared motor. You can get these here. this one has 15 revolutions every minute - nice and slow.

2. 2 X 5mm LED's. I used yellow ones.  They can be purchased here on Ebay

3. Plastic diffusers for the LED's.  I used some from a set of solar LED's.  You don't have to do this but it makes the LED light softer.

4. Small peice of dowel wood.

5. PIR sensor light - you can buy these here

6.  PIR sensor (just the sensor).  Buy these here

7. Copper wire - I used 2 types, 1 thin and 1 a little thicker.  These can be purchased from your local hobby shop.

8. various coloured wire

9. Various brass attachments.  i purchased these from my loacl hardware store. 

10. Samll square peice of wood for base

11. Battery holders.  The voltage I used was 7.5v so I used a 3v and a 4.5v battery holder.  These can be purchased from your local electronic shop

12. Tiny plane! I used this one

Tools

1. Phillips head screwdriver

2. Hot glue

3. Soldering iron

4. Dremmel

5. Drill

6.  Pliers

Below is how to hack the PIR LED sensor.  Take your time and be careful with the cutting!

Steps:

1. Un-screw the back of the sensor
2. Un-screw the circuit board
3. carefully remove the circuit board from the cover

Steps:

1. First you need to cut off the LED's. Make sure you cut them off at the top and leave the wire sticking out the top.

2. Add the battery leads. Make sure that the polarities are correct

3. Solder wires to 3 sets of the LED legs. These will be attached to your motor and LED's.  If you want to only the sensor to activate one thing like a motor, then you only have to add 1 set of wires to any of the LED legs.

4. Next cut off the PIR sensor - BE CAREFUL!

5. Solder wires to the legs where the PIR used to be

6. Solder the new PIR sensor to the wires making sure you have the sensor on correctly.  If could also just solder back on the PIR sensor you cut off.  Just make sure that you leave some wire on the PIR sensor itself.

7. Solder on the motor.


Note: Test - The motor should come on for a minute and then turn off. If you move in front of the sensor the motor should come back on. If not you probably have wired-up something wrong re-check everything and try again.

Next is to mod the original case so you can put the circuit board back in without it taking-up much room. This will enable you to use the on/off switch on the PIR sensor and will also protect the circuit board

Steps:

1. Use a dremmel to cut away the sides.

2. screw back in the circuit board.

3. Pull the wires through the LED holes.


Done! Now you can use the sensor for anything that takes your fancy.

Now you have your sensor ready to go, the next step is to put it into something. 

Modding a Globe
There is heaps of web info on how to pull the insides out of a globe.  If you need instructions more in-depth than the below – check out this from TeamDroid.  My only suggestion is to get an old style filament globe and not a halogen, as these are hard to do.  The globe in the pictures is a halogen and this broke on me when I tried to get the insides out.

Steps:

1. First remove the little piece of metal at the bottom of the globe.  Pliers usually will get this off.

2. Next use needle nose pliers to break the black glass at the bottom and remove

3. Inside the globe you will see a glass tube, break this and push a screwdriver down the hole.  This will separate the glass tube from the globe.

4. Next you will need to make the hole bigger – this is the dangerzone!  It’s very easy to break the globe so take your time and take little chips out of the glass with a pair of needle nose pliers.  One trick is to trim off some of the tin from the bayonet – this way you can make the hole a little bigger which will help remove the glass.

5. If the globe has white frosting inside, use some salt to get rid of it.

Tip – Hold the globe in a rag so if it breaks it doesn’t cut you.

Hopefully now you have a hollow globe

Now you need to stick something in your globe.  I decided on the below.

Steps:

Motor
1. Solder 2 pieces of copper to the motor legs.  Make sure they are straight.
2. Next bend a piece of thin copper as shown and solder onto the motor.
3. Superglue the little plane onto the other end of the thin copper.

LED’s
1. Bend 4 pieces of thin copper as shown below. 
2. Solder the bent ends to the LED’s making sure everything is straight.
3. Add the diffusers to the end of the LED’s.

Dowel
To ensure that everything sits right inside the globe, you will need to make some type of support which the copper wires can go through.  I decided on a piece of dowel which worked well

1. Shape the piece of wood so it fits tightly into the bottom of the globe
2. Mark-out on the dowel where to drill the holes.  Initially I cut out a small piece to use but decided to make all of my shaping and drilling on a big piece which I cut down later.
3. Drill

Steps:

1. Carefully put the plane and LED’s inside the globe
2. Push the other ends of the copper wire through the dowel.
3. Push dowel into place into the end of the globe.
4. Straighten everything up inside and once done use hot glue to stick everything into place.
5. Cut the excess copper wire off and attach some wires.  It is also good to add some heat shrink.  The wires that are shown in the pictures below I decided not to go with.  Instead I used some twisted wire that I pulled from an old computer. 

Now you should have a globe with a plane and 2 LED’s inside – who’d have thought!

Initially I went with blue LED's but decided that these looked too cold and went for some yellow ones.  You can see in some of the images that there are blue ones sometimes and yellow other times.  If you are thinking of making this, make sure you decide what colour you want first as it was a pain in the ar#& trying to change them.

To make the stand I decided to go use some brass plumbing fittings.

Steps:

1. Find some fittings which fit the end of the globe.  This bit is up to you on how you want it to look.  I just went to me local hardware store and found a few fittings that I thought would look a bit like a light socket.

2. Solder a piece of brass pipe to the fittings.

3. Solder more fittings to the end.  The end fittings are there so you can screw them into the base.  What that base is, is really up to you.  I found a copper pot at a trift shop which worked a treat.

Finally- the last step is to wire-up everything

Steps:

1. Thread the wire from the globe through the brass pipe to the base.  Screw together as shown.

1. Connect the wires from the sensor to the wires from the globe making sure polarities are correct.

2. Drill a hole in the base and add the PIR sensor.  Hot glue into place

5. Solder or glue in the globe to the brass fitting.  I managed to screw mine in a fair way by dremeling the thread of the coppoer fitting.

3. Add the battery.

4. Test.

That’s it!  You should have a pretty neat looking um…plane in a globe?  Set-it up in a place that gets some foot traffic and watch it come to life.

Thanks for checking it out and if you have any questions let me know.