Automated Pill Cutter - Progress Blog 1: 9/10/2021

Hello and welcome to our first blog post! This is a blog for the University of Houston's Mechanical Engineering Capstone Team 35: Progress Blog 1.

We will post regular updates of our capstone project as blog posts for the purpose of fulfilling course requirements, but also as a way to keep any interested persons up-to-date.

First, I'd like to shed light on the problem motivating our project idea; that is the inability for many consumers to cut prescribed pills to the dose that is best for them both effectively and financially.

For context, as costs of pill medications have risen across the United States, so too has the practice of consumers to split pills of higher doses (there is not a significant change in price from an increase in dose) [Cohen]. Consequently, consumers are at risk of taking the wrong amount of medication.

That is not to mention those consumers which are recommended to take a specific dose by splitting the pill but receive a dose less than what is deemed acceptable by using a commercial pill cutter that is limited by pill shapes and sizes [Borja-Oliveira].

Therefore, our solution to the problem is an automated pill cutter that will efficiently cut any pill. By this, we intend for the device to recognize a variety of most, if not all pill shapes, sizes, and levels of hardness; and, it should be able to do so with no less than 97 percent mass efficiency. Additionally, the device will feature a user interface for the purpose of tabulating the desired pill schedule, as well as a storage system to facilitate this.

With that being said, the journey to the final solution will not be so straightforward. Our team will have to overcome a couple of big challenges first.

Figure 1: Pill length of common medicines

Figure 2: Different types of pill shapes

The first big challenge for the proposed solution is being able to process pills of all shapes and sizes. As shown in Figures 1 and 2, pill sizes range from 3 mm to almost 25 mm, with their shapes varying significantly. The design of the device needs to consider the change in size and shape of each pill in order to produce consistent, clean cuts.

Figure 3: Mass loss after spitting.

The second big challenge for the proposed solution is in fact producing consistent, clean cuts to all the pills. There is no set standard as to how clean a cut needs to be for the efficiency of a pill to not decrease; however, it is recommended that the percentage of mass loss after the cut is less than 3 percent of the original mass [Green].

Additionally, considering that the maximum average hardness of standard pills is about 10 kiloponds, the device needs to exert enough force on the pill so that it produces a clean cut where the efficiency of the pill does not decrease by a significant amount [Molavi].

From the proposed solution, many consumers of pill medications should be able to save more money and rest easy knowing that they are getting the most accurate amount of their dose. However, while that is good and all, the team still faces one major challenge: the fact that some pills cannot be cut because their function is different from that of standard pills.

As of right now, the device would give the user the option to decide whether he or she wants the pill cut or not. The team is considering however whether to design the device in such a way that it detects the type of pill and then decides for itself whether or not the pill needs to be cut. Yet, this proposed addition to the solution would pose a significantly difficult challenge, as there is an enormous amount of different types of pills; detecting which ones can and cannot be cut is difficult.

References

Borja-Oliveira, C. R. de. (2013, February 1). Pill organizers and pill cutters: risks and limitations. Revista de Saúde Pública. http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0034-89102013000100016&lng=en&tlng=en.

Cohen, C. I., Cohen, S. I., Weissman, E. M., & Dobscha, S. K. (2000, April 1). Potential cost savings from pill splitting of newer psychotropic medications. Psychiatric Services. https://ps.psychiatryonline.org/doi/full/10.1176/appi.ps.51.4.527.

Green, G., Berg, C., & Polli, J. (2009). Pharmacopeial Standards for the Subdivision Characteristics. Pharmacopeial Forum, 35, 1598–1612.

Jacobsen, L., Riley, K., Lee, B. R., Bradford, K., & Jhaveri, R. (1970, January 1). Tablet/Capsule size variation among the most commonly prescribed medications for children in the USA: Retrospective review and FIRSTHAND Pharmacy Audit: Semantic Scholar. undefined. Retrieved September 10, 2021, from https://www.semanticscholar.org/paper/Tablet%2FCapsule-Size-Variation-Among-the-Most-for-in-Jacobsen-Riley/8dc11c4eb3e9822b86ce832290236469cca3a378#paper-header.

Molavi, F., Hamishehkar, H., & Nokhodchi, A. (2020, September). Impact of tablet shape on drug dissolution rate through immediate released tablets. Advanced pharmaceutical bulletin. Retrieved September 10, 2021, from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7539314/.