Final Project


For the final project I started by thinking about making two bracelets that are connected together wirelessly and always send the pulse rate together. Then, I talked to Neil and he told me that this project is actually more than one project and the networking part of it is a whole another project.

During fab academy I realized that what Neil said is absoulotley correct. And I need to make only one bracelet if I want to complete the project, but if it is only one bracelet then I won't like the project.

The project idea

I started thinking about another projects that I can make. Then I remmembered a project that I worked on with my students before so I wanted to make another version of it. That project had a soil moisture sensor and LEDs that blink when the soil needs water. All the components where connected to arduino.

Now, I thought of making a project that is similar to the previous project I made but I will use the skills I learned in Fab Academy. I will make the project compact and it will be a product that anyone can buy and use for to water his potted plant.

The project name will be AutoFarm. It is a device that helps people to take care for plotted plants. It can be implanted in any plant pot and then it will water the plant automatically when the plant needs water.

The project will have a soil moiture sensor. It will be connected to a microcontroller that will control a servo motor which is controlling a 3d printed ball valve of a water container. When the plant needs water, the servo will open the valve to water the plant, when the soil is moist the sensor will sense that, so the microcontroller will send a signal to the servo motor to close the valve. The system will be powered by a 9v battery, and everything will be fixed on an acrylic piece that I will design and it will have vinyl parts on it for the logo and to make it look nicer.

Prototyping with Cardboard

To start with this project I wanted to make card board prototype. To see how the project will look like and to see how to fix the components on it.

The first one was with black card board and with just drawing the components. Here it is:

I wanted to make one more prototype that will really help me in making the design. To make the prototype I needed to firsly bring all the components I needed. I have the sensor, a servo motor, battery, a circt board of servo motor (I used my friend ahmed galal's board to prototype), and card board to make the body of the container and to put all the components on it. I tried to fix all the things together but it didn't work so well because the card board I used is weak. Here is the result:

Then what I tried make a prototype with stronger cardboard, I cut the cardboard then attched all the components I have.The card board in white will be with acrylic in my final product. The cardboard colored in red is the water container which will be 3D printed, below it is the servo motor, then the circuit board, then the soil moisture sensor. And on the back is the 9v battery. The only missing part is the valve that I haven't thought yet about how I'm going to make it.


After making the prototype I started working on the electronics so I can start programming and testing the idea. I started working on the hello.servo.44.cad and then I added to things on it.

I added to the board two thing. Soil moisture sensor, and an LED to debug.

I connected the sensor signal to PA0 and VCC to PA2 so I can turn the sensor ON and OFF. And the LED to PA3. Here is a picture of the board:

Here is the board after milling it:

The board after putting the electronics components:

And I soldered 2x6 pins to the sensor:


For the programming part I worked on it in the input devices week and the output devices week. Firstly, I worked on the sensor programming in the input devices, and I made an LED turn on in certain soil moisture value, and then in output devices week, I worked on the final project board. As I made the servo motor rotate when the soil moisture reaches certain value.

3D Printing

The valve

The first thing I was thinking of is the valve, I was thinking of making a ball valve with 3D printer. I looked in thingiverse for ball valve designs, but when I looked into the designs I saw that they are not water tight.

I also was thinking of buying a valve and then make a 3D printed part than can link it to the servo motor so I can open and close the valve. But Francisco didn't like the idea, he told me that this will make the project bigger and also it is always better to make than to buy, when possible.

Then I came up with the idea of the tube that I'm using now in the final project. The difficult part was looking for the suitable tube in terms of size, length and stiffness.

I looked everywhere but I couldn't find the thing I'm looking for, so then I brought a tube from a Planting Spray.

But it was a little bit more stiff than I want but I helped me to do some trials but then I changed it to the green tube I'm using in my final project, which softer and easier to bend.

The ring

I wanted to make a design of a part that fits in the servo and controls the movement of the tube. Firstly, I made a design of a cube that has many holes to see what is the best size to use for the servo I have and it was 4.9mm.

Then I made one with the size I want and with a hole to put the tube through it

and finally I made it look like a ring to minimize the size

The container

The container was easy to make because I already had the design in my mind. Here is the container design, it can have 100 mL of water.

The only hard part was the water container nozzle. Because I didn't know if the printer will be able to print such small part, here is one of my trials.

The problem was that the printer starts printing another layer before finishing the first one. Then Francisco adviced me that in the custom setting in Cura, modify the print minimum layer time. I changed it to 10 seconds

I started printing and here is the final result

Laser Cutting

I started making the design of the body of the project that will hold the all the project components togethers. The first prototype was with cardboard, but then I wanted to make it with MDF, so I designed it in CorelDraw and I assembled everything together. Here is the result.

After this iteration I realized that the servo motor shouldn't be under the water container directly, because this way it pulls the tube when it moves it. The servo should be shifted to the right.

Then, I kept optimizing the design, and here is a picture that shows the versions I made for the sheet design.

In the trials I was cutting MDF.

And when I finalized the design I cut the design in acrylic

Fixed all the components on it

Vinyl Cutting

The final step was making the vinyl stickers. My design consists of two parts, the project name and the tree leaves.

Firstly, I started with the project name logo. I looked for fonts in the internet and I liked this font Copperplate Gothic Bold and I used it for the project logo,

Then I wanted to fill the container with plants leaves stickers. The first step was knowing the exact area of the container front, and I got that from fusion.

After that I looked in the internet for black and white clip art leaves so I can easily trace it and convert it to vector using CorelDraw, and this is what happened and here is the final design.

After that I cut the vinyl.

And here is the final result.

Neil's Comment

I'm very happy that Neil liked my project and saw that I used a range of skills to make the project.

He had one single comment and it was about the cable connected to the sensor, he said that connecting it the way I did is a vulnerability and that I should cover it with silicon.

So I made a mold using CorelDraw and here it is

Then I put the cable in the mold and put silicon on it

Here is the final result.

You can see that I also changed the screws to steel screws


Video of the final project working

Summary Slide


Creative Commons License
AutoFarm By Ahmed Abobaker is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.