Everyone loves pet animals. But they come with a lot of responsibilities. So why not make a animal for yourself or gift it to a friend. Of course, it wont replace the real animal but you come a little closer to having one. You can keep it on your shelf or use it as paper weight.
Here I have made a Pet Tortoise with the help of Clay and added some electronics to it. The electronics include a Neon type light effect from below the tortoise. It also includes a touch sensitive switch such that when you touch the tortoises back, the LED's in the eyes glow.
Step 1: Here's a Video of the Finished Tortoise
Step 2: Assemble the Components
Things you will need :
1. RGB LED x1
2. General purpose Printed Circuit Board (PCB)
3. Superbright Green LED x1
4. 3V cell
5. BC547(npn) x2
6. Resistor 1k ohm x1
7. 3V cell Holder
8. Clay or Mseal
10. Soldering equipment
Step 3: Block Diagram
To make this Tortoise, I divided the electronics into 2 main parts. One for the Base/Bottom LED's and second for the touch switch. Both get power supply from a single 3V cell which is connected in parallel. The two parts are as explained in below steps.
Step 4: Making the Base
The base part includes two LED's to give the neon effect as shown in the photo. The two LED's are a superbright green LED and a RGB blinking LED which changes color with time.
The circuit is as shown in the photo above. You can use any other color LED and can connect the circuit as you wish keeping in mind the end result remains the same.
One switch is a normal toggle switch to switch the whole circuit ON/OFF. While the other switch is a DPDT switch used to switch which LED is used Green or RGB. Only one LED can remain ON at a time.
You can add an additional switch to decide to keep the touch switch ON or OFF. Such a configuration makes sure the Cell used lasts for more time.
Step 5: Touch Magic Revealed
As stated in the introduction, the eyes of the tortoise glow when you touch the back shell. This is done using a Touch Switch.
The Touch Switch includes 2 BC547 npn transistors which are connected as shown in the circuit. When you touch the base of the 1st transistor the gain increases considerably and current flows through the collector to the emitter.
Keeping the technical stuff aside, solder the components as shown in the circuit diagram. The +3V and GND are connected to the cell. The other two wires which are to be connected to the LED are drawn out and the Touch wires are drawn out. This completes the touch switch used.
Step 6: Assembling the Two Main Parts- Base and Touch
Assembling the two parts is easy. Just take them and use a little clay to insulate them with the touch on the top and base on the bottom. Then cover the whole thing appropriately with clay. Different colors of clay are available, you can use any of your choice. While covering it with clay make sure the touch wires stay out and don't cover the LED's.
Step 7: Making the Legs and After Assembly
Take small amount of clay and make cylindrical rolls and use them to make the front legs. Let them dry and harden and then make the hind legs. Let it harden. Make sure the tortoise stands on all four legs.
See how I kept the eye LED and the touch wires outside. Give the tortoise base LED a test run to make sure its working. You can add a tail so that it will look cute.
Step 8: Making the Head
Take small amount of clay and attach to the head. Make the neck little shorter than the head. Refer photos to understand it better.
Note : While making the head make sure it doesnt stick to the LED or they will give low light.
Step 9: Making the Shell
Take a long piece of clay and shape it in shells shape. Attach the whole shell on the back of the tortoise properly. Use glue if you want so that the shell stays fixed to the back. The touch wires that were left out, remove the insulation from them. Make sure they don't break while fixing the shell.
Use a file to shape the shell properly after it hardens.
Step 10: Checking the Electronics
Now we have almost built the whole thing. Check everything from base LED's to the touch eyes LED. The Green an the RGB LED should be working. The eyes LED should glow when you touch the wires as shown in photos.
Step 11: Coloring the Tortoise
Final part is coloring the tortoise. Paint as per your wish. I have painted the shell with acrylic light green and the body with dark green. You can also get texture on the shell to make it more attractive.
Bend the touch wires on the shell which were out. Take small amount of clay to attach the other end of the wires to the shell. Do not color on the wire.
Step 12: Finalising
Now the coloring and electronics is done. Do some final touches and wrap the gift for your special ones. It looks good on your shelf and you can even use it as a paper weight. Your own personal Pet Tortoise :)