Automatic Book Recycler

About the Project

This project was my capstone project for my undergraduate mechanical engineering degree. I worked with a team of five people to complete this project. The goal of the project was to build a machine that could separate the recyclable and non-recyclable components of a book. The project was built for the Northeastern University facilities team to aid in their goal of recycling outdated textbooks and lawbooks.

The machine was tasked with separating the pages (recyclable) from the spine and covers (non-recyclable) of various sizes of books. This was a phase two project meaning that we were given the outline of the separation process along with a half functional prototype from a previous team and were tasked with taking their process and turning it into a fully functional and safe automatic system.

I acted as team lead and primary mechanical designer for the project. I completed the vast majority of the CAD for the project with my primary system being the book carriage. However, along with the book carriage I also designed the primary motion system, the structural frame, and pneumatic system.

The book carriage (aka the nest) was the most complex system in the machine and had three tasks:

Locate the book within the system for cutting
Fixture the book in all 6 degrees of freedom so that is was cut properly when dragged through the saw
Separate the pages from the covers

To locate the book for cutting, the nest included two pistons and a linear motion screw system. To cut the book, the entire nest was mounted on a linear rail system allowing the book to be pulled through the bandsaw. Once the book had been cut, a vacuum system suctioned to the covers to hold them in place as the bottom the nest hinged open to drop the pages into the recycling bin.

Our team accomplishments include a complete overhaul of the mechanical design, a complete electrical box with multiple safety integrations and PLC control, and manufacturing the vast majority of components. A detailed system process can be found below the photos.

(Click images for more information)

The Project in Detail

System Process:

Book chute door is opened and a book is loaded into the slot
When the safety switch senses the door is closed the system activates the run button
When the run button is pressed the book chute opens its back door and drops the book into the waiting nest
The book is then pressed into a rigid locating beam that houses a switch that activates with a designed force
When the book activates this switch, the two pistons in the nest extend to lock the book in all 6 DOF
Once the book is located, the bandsaw turns on with a PLC controlled relay
The book is then pulled through the bandsaw by the primary linear motion system where it saws off the spine
The spine falls into the trash and the covers and pages are left clamped by the Z axis piston
The suction cups on the floor of the next and top of Z axis piston engage to hold onto the covers
The nest moves above the recycle to drop the pages
To drop the pages, two solenoids retract to allow the bottom to hinge open
Simultaneously, the Z axis piston retracts to keep the top cover on the suction cup
The nest then moves over the trash bin where it disengages the suction to drop the covers
A final piston retracts the nest bottom door allowing the solenoids to click back into place
The whole nest then returns back to its original position waiting for the next book to be loaded

Additional System Details

Primary linear motion system included a startup homing sequence
The book chute opening acted as a book maximum size regulator
The chute door allows a new book to be loaded while the machine is running
To remove the trash cans, a hinged gate with a safety interlock can be opened
The electrical cabinet contained breakers for all high power components along with full circuit breakers

Project Video