Intelligent Waste Classification / Segregation System

This project focuses on the creation of a smart waste bin designed to facilitate recycling. Equipped with a waste sorter that uses artificial intelligence and advanced sensors, this innovative system can automatically identify and separate the waste that is deposited in it. This means that users will not have to worry about deciding which bin each type of material goes into. The combination of artificial intelligence and sensors ensures accurate and efficient identification of waste, making the recycling experience easy and accessible for everyone.

Furthermore, this project has emerged as a way to integrate technology into a University of Salamanca goal of more sustainable campuses. By promoting more intuitive and effective recycling practices, this project not only contributes significantly to environmental sustainability, but also supports the university's efforts to create a greener and more eco-friendly environment.

Goals of the project

1. To differentiate between at least three types of waste: plastic/metal, glass and paper.
2. To develop a modular, simple and user-friendly design for the sorting machine, allowing it to be adapted to different contexts and needs.
3. Implement a computer vision system that allows the accurate identification of different types of waste, improving the efficiency of the sorting process.
4. Integrate specialised sensors to detect specific characteristics of the waste, such as material composition, size and shape, in order to optimise the accuracy of the sorter.
5. Ensure interoperability and easy integration of the sorting machine with existing waste management systems, facilitating its adoption in various environments.
6. Design an intuitive user interface that promotes active participation, providing information on the positive environmental impact of correct waste sorting and educating users on sustainable practices.
7. Automate the transport of recyclable material to the appropriate container.

Restrictions

1. The machine can sort waste of different sizes and shapes, but performance is best with cylindrical or cubic shaped objects. The waste must have dimensions similar to a Coke can and a maximum weight of 1 kg.
2. Current design constraints limit waste sorting to objects within these dimensions and weight. 
3. The capacitive sensor used is highly sensitive for detecting plastic waste; however, any object in contact with or near the plastic can affect the accuracy of the sensor.

Future Implementations

The waste sorting machine is currently a prototype. With modifications and improvements, the concept of this machine can be implemented in homes, offices and industrial applications. These improvements could include expanding the capacity to sort a wider variety of waste, increasing the accuracy and efficiency of the system, and adapting the design for different environments and specific needs.

For the construction of this intelligent recycling system, it is essential to have a detailed list of all the components and materials required. This list, commonly known as a Bill of Materials (BOM), provides a clear and structured overview of each required item, facilitating both procurement and resource management. The BOM for this smart recycling system project is presented below. Each item includes the description of the component, the quantity required, the unit price, the total price and a link to where the product can be purchased.

For the design of the smart recycling machine, we meticulously designed each part using SketchUp software. This allowed us to visualise and refine each component in a three-dimensional environment prior to manufacture. In this section, we provide the complete model in SKP format, which includes all the details and specifications of the designed parts. 

This model facilitates the understanding of the final assembly, but also serves for future modifications and improvements to the system.

In this step, we will focus on the electrical system that will allow the waste sorting mechanism to work automatically. We will detail each component, its connection and the necessary tests to ensure that everything works correctly.

Components

Arduino Due: The main microcontroller that controls all components.

DVD motors: Two DVD motors connected to an H L298N bridge.

NEMA 17 motor: A stepper motor controlled by another H L298N bridge.

Servomotors: Two servomotors connected directly to the Arduino.

Proximity sensors: One capacitive sensor and one inductive sensor connected to the Arduino.

VL53L0X sensor: A laser distance sensor (ToF) connected to the Arduino.

L298N H-bridges: Motor control modules used to control the DVD motors and the stepper motor.

12V power supply: Supplies power to the components.

Connections

DVD motors:

• Connected to the L298N H-bridge.
• The motors have two-wire connections (normally yellow and green) connected to the H-bridge outputs (OUT1, OUT2 for the left motor and OUT3, OUT4 for the right motor).
• The H-bridge is connected to the Arduino via control pins (IN1, IN2, IN3, IN4) and powered with 12V (GND and VCC).

NEMA 17 motor:

• Connected to another H-bridge L298N.
• The motor has four wires connected to the H-bridge outputs (OUT1, OUT2, OUT3, OUT4).
• The H-bridge is connected to the Arduino via control pins (IN1, IN2, IN3, IN4) and powered with 12V (GND and VCC).

Servomotors:

• Connected directly to the Arduino.
• Servos have three wires: signal (connected to PWM pins of the Arduino), VCC (connected to 5V of the Arduino) and GND (connected to GND of the Arduino).

Proximity sensors:

• Connected to the Arduino.
• Each sensor has three wires: signal (connected to digital pins of the Arduino), VCC (connected to 12V) and GND (connected to GND).

VL53L0X sensor:

• Connected to the Arduino.
• The sensor has several connections: VCC, GND, SCL (connected to an Arduino clock pin), SDA (connected to an Arduino data pin), and possibly other control pins.

L298N H-bridges:

• Connected to the Arduino to receive control signals.
• Powered by the 12V supply.
• The H-bridge outputs are connected to the corresponding motors.

Computer power supply unit (PSU):

• Provides 12V and 5V.
• The 12V outputs are used to power the L298N H-bridges and other components requiring 12V.
• The 5V outputs are used to power the Arduino and other components requiring 5V.

Attached is a photo showing all the power supply connections. In this project, only the soldered connections of the grounds and the 12V and 5V outputs have been left.

In addition, we have developed a specific web platform for recycling devices or machines, which allows real-time monitoring, remote management and collection of usage data. This platform facilitates the integration and control of the sorting machines, improving their efficiency and allowing a centralized management of the recycling system. All the code has been developed with React and Node to create the entire web platform and this code is free; you can find it at https://github.com/AnOrdinaryUsser/BESS_SAS.

For this project, an HTML page has been designed for its dissemination, providing detailed information about the initiative and its benefits. This page allows users to learn about the objectives, operation and environmental impact of the smart recycling system.