University of Southampton creating the 4 Bin Swopper prototype

The University of Southampton are a regional partner for our Leaders Award competition which asks pupils aged 3-19 the question “If you were an engineer, what would you do?”. As part of this continued partnership, the university have selected a pupil’s idea submitted to our Leaders Award competition to turn it into a working prototype over the 2024/2025 academic year.

Pupil designer Maisie, a pupil in Year 3, will see her engineering idea the ‘4 Bin Swopper’ turned into a reality! Her idea is a bin with robotic hands that will automatically move the rubbish into the right sorting bin category.

Introduction to the ProtoTeam

The University of Southampton School of Engineering offers challenging Group Design Projects to small teams of final year undergraduate students.

Five engineering students decided to pursue the design of a smart recycling bin eco-design, inspired by Maisie’s ‘4 bin swopper’ concept: Duvayndren Jegathesan (Mechanical Engineering), Zhe Wen Teh (Mechanical Engineering), Hiroki Yamashita (Mechanical Engineering), Darcy Kirwan (Mechanical Engineering) and Ji Kit Lee (Aeronautical Engineering).

Kit had relevant experience working on image recognition using artificial intelligence. He is working on the system to recognise waste items from taking a photo as it is deposited in the smart bin and training a single board computer to match that photo to similar photos of known waste items.

Why have they chosen this pupil idea?

The University of Southampton chose this design because, as Maisie suggests, recycling works best when waste items are collected in the correct compartment for collecting and processing them. Placing waste items in the correct part of a bin remains challenging. Some people need assistance to avoid waste becoming mixed or contaminated.

Maisie correctly identified the challenge for partially-sighted people, or those who do not understand instructions for recycling. She proposed a mechanism for automatically sorting waste items in her concept. The concept also attracts interest in using it through its fun design and provides information to users through a screen.

There are worthwhile engineering challenges, both in identifying waste items and transferring them to suitable containers ready for collection. Also in understanding the interface needed for promoting recycling to users such as primary school pupils.

Starting the prototype

The GDP team’s initial task was to understand the benefits of adding automation to a bin. They researched existing bins and the few smart bins which have not currently become mainstream. They are also exploring the needs of primary schools to segregate their typical waste items.

They began sketching design ideas for the mechanisms needed to safely receive a single item of waste deposited in the bin to hold it for a photograph to be taken, then moving it to drop it into one of 4 containers. The bin also needs to provide access to collect the 4 containers when they are full so the waste can be transferred for recycling and ideally monitor when the containers are getting near full.

The sorting of waste uses image recognition. Like people need to be taught what distinguishes a plastic bottle from a glass bottle, a machine learning algorithm (a form of artificial intelligence) needs to be trained using suitable images of typical items of waste. The team have found databases with such images and started experimenting with training.

Fig. 2 Example Data Set for Waste Classification a) plastic containers b) paper

The overall design was modelled using computer aided design (CAD) software and presented to Maisie and to Primary Engineer staff in November. Maisie and her teachers kindly agreed that illustrations for the front of the doors could be prepared at her school. These can be used to make the 4 different types of recycling look more interesting.

The team plans to refine the detail of the components of the design to start prototype manufacture in February to be able to test the first version of the mechanisms, as well as the camera and waste recognition system.

The team hope to visit Maisie and her class at Evendons Primary School to discuss their design and how they are addressing the challenges of the project. That will help their learning towards becoming a professional engineer.

We are looking forward to the next update!