The problem Sol-Bin solves

There is not much incentive for people to sort the waste or recycle. What if we could provide incentive so waste management and recycling is easier. So we have built

• Dustbin powered by ESP8266 Microcontroller with Weight sensor and ultrasonic sensor
• API and Dashboard Utilities built in django to bridge multiple dustbins scattered in the city and manage them
• A web app built in Next.js for people to interact with the dustbin and get incentivized in solana or in money based on the sensor data of weight, height change.
• Solana Marketplace for municipalities to create auctions for recyclable items with longer shelf life where recycling companies can bid for the created auction.

This platform is meant for

• Recycling companies who want to cut the price in the sorting process and reduce the number of employees while creating more incentive
• for cities that have problems with recycling and waste management.

Recycling is hard as it requires fetching and sorting. It is a low value job and less people are willing. if fetching and sorting becomes easier then waste management is feasible. So how ? Through the concept of hotspots which is a place where a specific type of waste is produced the most. Example: paper waste gets accumulated most in school and uni areas. We place the paper dustbin(can only insert paper) near the university area. Since we have specific dustbin for specific waste, the sorting process is completely cut and through our analytics page we can know which dustbin is filled or about to be filled and then we can send a truck to fetch them. So we don’t require huge numbers of active workers to fetch for us.

Also for Municipalities that don't have their own recycling houses, it can create auctions for high shelf life waste such as papers and metals through the use of our dashboard. And other recycling houses can bid on it using solana blockchain. The UID for the auction will be owned by highest bidder on the end of auction date.

Challenges we ran into

Getting Anchor framework to run

We started working with anchor framework on windows machine and soon ran into the problem which didn't allow anchor cli latest avm to be installed. So we had to switch to wsl and cargo build times are unexplainably slow.

Writing Solana programs with anchor

We had a hard time understanding how PDA(program derived address) worked and didn't know what seeds were. But later we were clear after rewatching jpcaulfi workshop session

Integration problem

We are team of four and three of them were assigned for webapp. one of us had to use Next.js through create-solana-dapp in typscript, one decided to use next.js but in javascript and one decided to use create-react-app. So our project is like a monorepo and url routing is still a problem.

Smart Dustbin Load sensor calibration

Load sensor needs a calibration factor in order to work. We didn't know that started to check the wires and rewire it, and later when 12-13 hours was left we came accross the blog and could get results within 10%-20% error. A big margin but we are happy with it.

Deployment Problem

Our API and dashboard is hosted on pythonanywhere and in its free plan only HTTP scheme is allowed. Our Webapp is hosted on vercel and by default it gives HTTPS scheme. And modern browsers doesn't allow http scheme GET and POST requests to be called from HTTPS. We tried and you can see the error for yourself at