Introduction: EAL - Embedded Programming: Candy Mixer 1000

About: Student from Lillebaelt Academy, Odense, Denmark.

For our project in Arduino we have decided to make a mixer for candy. The idea is that the user can push a button and then the motors will start to eject the candy into a bowl, and when the program have run its course it will stop.

The first draft was to make a mixer with 5 kinds of candy, and a load cell to measure the weight, but due to limited time and trouble getting the weight(load cell) to work, we have scaled the program down to 2 types of candy and using a timer instead of the weight to ensure the same amount of candy in each bowl.

Step 1: The Design

Our model is made with 2 containers set in a housing. The candy will be put into a container in the top of the model, where it will glide down into the tube with the auger. When the motor starts the auger will bring the candy forward, until it falls into the bowl.

We have found the design for the tubes and auger at

Step 2: How It Works

The way the mixer works, is that we have 1 type of candy in each tube, and when the user pushes the button on the front, the mixer will mix up the 2 types of candy into the bowl.

An LCD display will then state a message when the mixer is running and again when it is done.

Step 3: The Circuit

For the project we need to connect the 2 motors, the LCD display and a push button to the arduino.

Step 4: I/O List

Step 5: The Program

The program is started when the user pushes the button, and then both motors runs for 5 seconds, then switches to a new mode where they run 1.5 seconds each for 3 seconds.

The LCD display will shift message from “Tryk Start” to “Blander” when the program runs.

Step 6: The Code

At the start of the code we define the pins used for the LCD Display, the 2 DC motors and the button.

In the Setup phase we define the button as an Input, the motors as Output, and we set the head line on the LCD display to “ Candy Mixer 1000”

In the loop of the code, we make a check of the button state to see when our program should start to run.

When the button is pressed the LCD display will change from “Tryk Start” to “Blander” and the motors will start their sequence.

In the motor sequence we first run the motors for 5 seconds simultaneous and then we run them one by one for 3 seconds.

Step 7: Evaluation

Unfortunately, we did not get the load cell to work as it would have made it a much better project, and the code had been more challenging.

During the course of the project we encountered several problems, most time was used trying to get the load cell to work, but we also had some with the candy getting stuck in the tube stopping the augers rotation. We solved it by putting a brick in the housing, where the auger meets the edge of the tube, so that the candy gets a little free room to fall into the space around the auger.

All in all a good fun project where we got round to some challenges and got a good model finished at the end.

Step 8: Candy Mixer in Action

A little demonstration of our little Candy mixing dispenser

Step 9: Extend the Project

Our original idea was to have a load cell connected to the mixer, so that when the candy got mixed, the load cell would monitor the weight and then stop the program when a surden weight was reached. Due to problems with the load cell we had, we never got round to incoorperate that.

So a mixer with 5 tubes for candy, a load cell for the weight, and a panel to type the weight wanted, would have been to perfect project to hand in, but time worked against us in the end so we ended up downscaling the project.