Introduction: Arduino Automatic Moneybank

How it works:

We constructed a moneybank with simple and easy electronics, accessible to anyone. With minimal electronic components we made a working mechanic. It works as follows: You put a coin onto the plate of the stuffed animal. The sensor inside the plate activates the motor, which turns the arms and the plate up. The coin slides down the plate, into the shaft inside the plush. The shaft takes it down and deposits it into a potential storage.

Required parts:

The required parts are easy to find and use, nearly anyone can use it. The list of parts is as following:


-A stuffed animal

-Thin wooden plates

-A tiny basket



-Servo motor


-9V battery



-Glue gun

-Soldering machine


Step 1: Using the Wooden Plates

First of all, we will be using the wooden plates to construct several different components of the structure. Reinforcements, boxes (including basket), the plate and the moving part. You can outline all these parts on a single board. The dimensions depend on the type of stuffed animal you're using.

Dimensions of box: 12x12x4 cm

Dimensions of reinforcements in limbs (2x): 8x7cm (U-shaped)

Dimensions of moving component: 5x2 cm

Dimensions of plate: 10x7.5 cm

These components will be used to give shape to the overall project.

Step 2: Preparing the Stuffed Animal

First things first, we will have to prepare the stuffed animal in order to be able to use it. We will have to cut a small opening (Do not make it too large) in the mouth of the stuffed animal. From there, we need to empty the stuffed animal, to make room for wires and electronics. Do not throw out the wool, as we have to fill the plush back up later. Then, place a few reinforcements in the body of the plush, so it does not fall over when standing on its own. Finally, we need to create a little 'basket' inside the mouth or stomach of the plush. This is where the coins will be transported to.

Step 3: Writing the Code

Using Arduino, the computer program, we will be writing our code. The code only steers our LDR and our Servo motor, so the code will be compact and easy to follow. The code we used can be seen on the image. If you wish to download the code for yourself, click Here.

Step 4: Assembling the Electronics

Now, we will have to assemble the different electronic parts listed before. The Arduino, with the proper coding, should be connected to the 9V battery, the Servo motor and the LDR. Wielding them together with wires and a soldering machine, We create a sturdy circuit. This circuit is all we need to utilise our creation.

Step 5: Putting Everything Together

One last step, we need to assemble everything together. Up until now we've constructed everything separately. Now it's time to put it together and finish the project. Place the Arduino and the 9V battery into the box. Guide the wires through a small hole at the top of the box. Then connect the wires to the LDR and the Servo motor. Connect the Servo motor to the stuffed animal and place it on top of the box. Reinforce the Servo motor with a simple beam for a sturdy base. Then, if the plush is able to stand up on its own (using the reinforcements) it is ready for use.