Pill Cutter - Progress Blog 2: 10/2/2021

Hello and welcome back to our team's second blog post! This is a blog for the University of Houston's Mechanical Engineering Capstone Team 35: Progress Blog 2.

First, we would like to reiterate our main problem statement. Even though current pill cutters provide an adequate method to split a pill, they offer a high risk for the patient. Many times, they produce “unclean” cuts which result in leftover pill fragments; and, thereby, the levels of active ingredients within these cut pills exceed the limits of variation. Put simply, the patient receives a dose that is lower than what is deemed acceptable [1]. Moreover, some pill splitters are only built for a specific shape and have a size limit.

So, our goal is to fabricate a reliable pill cutter that weighs less than 3 kg (as compared to current pill cutters) that can split at least nine different pill shapes for a full range of pill sizes, all while losing no more than three percent of the pills’ original mass. Ideally, the pill cutter should also be able to process/store at least 35 pills and meet FDA regulations for medical devices.

To help ourselves achieve this goal, we have developed a Gantt chart. The chart will help us track our tasks and milestones for the rest of the year for the duration of this project. Tasks can be run at the same time, while milestones should run in succession.

Figure 1: Projected Gantt chart

Next, we would like to explain the top technical issues our team needs to overcome. The first technical issue in the development of our device is in its ability to address the different shapes of pills. To solve this issue, we will analyze components of existing prototypes to see how they deal with multi-pill shapes. Our team will then narrow down the adequate elements and analyze them, modifying each piece to the team's ideal.

The second technical issue in the development of our device is in its ability to address different sizes of pills and to hold them in place. To solve this, our team will evaluate the solution of the first technical issue to determine what can be built within the inside of the device which can address the second issue. We will then create a new component to finally resolve the issue.

The third technical issue in the development of our device is in its ability to cut the pill in half with less than three percent mass loss. To solve this, our team will analyze the sharpness of the blade (used within the device), the shape of the blade, and the force required to cut the pill as cleanly as possible. We will then determine the best solution for this technical hurdle.

As of now, our team is proposing a pill-cutting system that will include a disk of multiple pill shapes, a customized, pill-gripping plier, a curved, triangular blade, and a user-aided cutting system. The storing/dispensing system will contain organizing containers for the split pills. The figures down below demonstrate our first attempts at developing a CAD model for our design.

Figure 2: Multiple-shaped disk

Figure 3: Pill gripping plier

References

[1] Borja-Oliveira, Caroline Ribeiro de. “Organizadores e Cortadores De Comprimidos: Riscos e Restrições Ao Uso.” Revista de Saúde Pública. Faculdade de Saúde Pública da Universidade de São Paulo, February 1, 2013. http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0034-89102013000100016&lng=en&tlng=en.