Process

Outline your approach to the project? What ideas did you generate and how did you refine or reject them? What did you research and explore? what were the design choices? What challenges were encountered and how did you resolve them?

My starting point is to choose what approach to measuring the condition of the drinks. 

1. My first trial is the using the photoresistor to detect if there are drinks in the fridge. It turns out photo resistor is more suitable for detecting food stock, for example, if there is food left in the fridge or if the food is out of stock. The photoresistor will sense the light once the food in the fridge is removed.

2. Since my goal is merely detecting one kind of food and requiring more precise metric, I came up with using the weight of drinks to measure the condition. After a while, I found the FSR (force sensitive sensor) is the right one.

This variable resistor is just like a photocell or a flex sensor. The resistance changes by applying force on it.

For this project, we will need:

Particle Photon;

Breadboard;

Resistor;

FSR sensor;

LED;

The LED is used to ensure the FSR is working without reading the output of sensor in the console.sensor in the console.

3. The circuit

4. The code