How to make a hydraulic robotic arm

Do you have a science project or science fair coming up soon and you have no idea what project to make which will blow everyone’s mind away and will get you your first prize? Well, don’t worry, we’ve got you covered! Today we will be showing you how to make a hydronic robotic arm! If you’re interested read more to find out how it is made.


Products needed for this DIY project:

1.      Cardboard

2.      8 syringes

3.      Glue

4.      Old battery

5.      4 pipes

6.      Popsicle sticks

7.      Water


Let’s get started with this DIY project!


Step 1:

Take a piece of cardboard and cut out the shapes that you can see in the image below. The longest piece of cardboard has to be 20 centimeters long and three centimeters wide. The other pieces can be cut to size accordingly after accurately measuring them and drawing them with the help of a pencil before cutting the final shapes out. You also need to drill two holes at the top and bottom of all the long pieces and one hole at the top of the shape that almost resembles a triangle.

Step 2:

Take two long pieces of cardboard and put two toothpicks through the holes you just drilled in the previous step to connect them. There should be enough gap between the two pieces for two syringes to fit. Make another one of these cardboard structures but this time diagonally connect it to the previous cardboard structure from one side. Put the almost triangle prices on the other side: one at the top and one at the bottom of the cardboard structure with the help of the toothpick. Put some liquid glue in all the places where you have used a toothpick to lock it in. Then, stick the whole structure on a square cardboard piece using some hothouse.

Step 3:

Drill a hole at the bottom of one of the syringes and connect it to the long cardboard pieces using a toothpick. Connect the other side of the syringe to the cardboard structure connected to the first one and secure both of them with a zip tie. In the same way, connect another syringe between the middle cardboard structure and the bottom almost triangle-like structure.

Step 4:

Now it’s time to make the main arms of our hydrology robot. Take a picture of cardboard and cut out all the shapes that you can see in the courier given below. Now it’s time to start connecting them. Take one of the main arms and connect it to the biggest piece using a toothpick and some liquid glue. Do the same thing for the other arm too. Don’t forget to also connect a bent metal wire to it. Also, put a piece of cardboard on each arm at the front by folding it in half and connecting it with a toothpick.

Step 5:

To attach this arm to the structure we built earlier, apply some hot glue to the front of the topmost cardboard structure and stick it in place. Then take another syringe and connect it to this cardboard structure and the metal portion of the arms using some liquid glue, toothpicks, and a zip tie.

Step 6:

Next, stick two big pieces of cardboard using some hot glue. After that is done drill a hole in the center and insert a small double A battery into it. Put some liquid glue in the hole so that the battery does not slip out. Then drill another hole at the bottom of the main cardboard structure and place it on the battery that you just stuck to the cardboard base. Take two popsicle sticks and put a syringe on one end which will be connected with the help of a toothpick. Use some glue to stick it to the side of the base.

Step 7:

Now let’s work on the control board of the hydraulic robotic arm. Take four syringes and fill them up with water. To make this more fun you could even add some color to the water. Connect each wire to a separate piece of pipe. After this is done mount the syringes to the control board by making a structure like the one given in the picture below. Then connect the other side of each pipe to the syringes in the main structure.

The principle used here is that when water is pushed out of one syringe it’ll travel through the pipe and go into the other syringe which will move the part that is connected to it thus helping it to pick up objects.

Your hydraulic robotic arm is now ready! This project uses products that you can easily obtain from your nearest store at minimal costs. Even the whole build is so simple and fun! Bring out the science lover in you and impress your friends and family by making this cool hydraulic robotic arm by yourself at home. Enjoy your latest creation!

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