Cup Punch Automation System

I worked with my 7-member engineering student team over one term to develop an environmentally sustainable, cost effective, and and safe design concept for our client, the FAST (Free Appropriate Sustainability Technology) group, whose work includes sustainable, open-source agricultural technologies to improve others' quality of life.

The peat cups they used to grow their crops in required small holes for water and air flow, which at the time they were punching holes in each one manually. As hundreds of cups were required every few months, the process was tedious and so a more optimal, automated cup punching mechanism was desired.

Researches and farmers who implement vertical farming need a renewable and affordable alternative to peat cups and a time efficient hole punching system for sustainable year-round farming to meet the increasing demand in their communities for accessible fresh produce.

Prototype a safe, affordable cup punch automation system that can create enough holes of the right size for multiple cups consistently, over a period of time. This would efficiently prepare cups that can then be promptly used for planting, improving the efficiency of the farming process to support its sustainable means.

As a mechatronics project, this process developed many skills such as problem-solving, collaboration, CAD, programming, and prototyping skills.

Parts of the prototype were 3D printed, while others were cut from available wood pieces for affordability. In the CAD concept, a clear 'ceiling' floor was incorporated so the mechanisms below could be clearly viewed during machine runtime to increase safety and awareness. The device was also designed to be easy to take apart to replace and clean pieces to increase its lifetime and reusability. The final prototype acted as a proof of concept.

Paper cups were chosen as the alternative to peat cups for this project due to their affordability and sustainability as they could biodegrade. They were also durable enough to not disintegrate after only a few trials.

An automated device would be a more time-efficient method because people could busy themselves with other work while the machine would take care of the punching process.

There were 5 main parts of the device that supported its automation:

1. Cup Die Design: Designing an entire 3D-printed die to sit inside the cup prevents the cup from collapsing inwards when punched. The upside down, inverted cup die shape also holds the cup securely when the dispenser drops it down. As the cup would be placed on an angle on the wall for vertical farming, I placed nail holes (9) on one side and the slit hole (1) on the opposite side to manage and follow the path of water flow appropriately.
2. Dispensing Mechanism: Dual servo motors and gear teeth were used to drop cups one at a time onto the cup die, programmed to be a timed process.
3. Punching Mechanism: A set of 9 nails punch into the cup and through the nail holes of the cup die using a rack and pinion system. This amount of holes was adequate for water flow when tested. The mechanism produces consistent holes for the planting conditions.
4. Slicing Mechanism: A razor swipes into the opposite side of the cup and through the slit hole of the cup die (one slit-shaped hole was a requirement for this project), producing a consistent slit for optimal water flow.
5. Trap Door Mechanism: Once the cup holes are created, the trap door attached to the cup die that the paper cup is on will swing downwards, dropping the finished cup into a collection box below the system, and then return to its original position to continue the cup-punching automation process. Cups can be taken from the collection box anytime for planting.

Apart from these, a PCA 9865 and Arduino UNO were used to connect and program the system.

The Cup Punch Automation System design was awarded 1st place among Cup Punch teams in the 2024-2025 ES1050 Showcase.

Since the device is designed for punching cups for vertical farming, which incorporates a variety of crops, a future step could be to create various cup-dies and hole-punching attachments to create difference kinds of holes that are personalized to each plant, therefore optimizing the device for a diversity of plants.

It would also be interesting to explore the idea of punching more than one cup on the cup die at a time and then test that no quality is lost, as this could further increase the efficiency of the system and therefore improve the sustainable farming processes it is meant to be used for.