Warfarin Automatic Home Medication Dispenser

Senior Design I

Project # P07009

Team 7009

Alan Strandburg, ME

Gordon Yeung, ME

Chris Abramo, ME

Nick Columbare, EE

Ntongho Amin, EE

Albert Lam, CE

Pre-Read Package

Project Background:

Warfarin is an anticoagulant used for blood clotting medical conditions. Dosages of warfarin need to be frequently adjusted to maintain effectiveness. For the first few months of the regimen, adjustments are made based on weekly or bi-weekly blood test results. This requires frequent coordination with the physician, patient and pharmacist.

Problem Statement:

Frequent coordination between the physician, patient, and pharmacist is time consuming, inconvenient, and poses a risk to the patient’s health by increasing the chances of error or a missed dose. Since patients taking warfarin require frequent dosage changes, a real-time adaptive system needs to be developed.

Primary Subsystem Focus:

  • Dispensing Mechanism
  • Reliable
  • Must be jam-proof and not cause damage to pills.
  • Robust
  • Must be able to tolerate driving vibrations and be able to operate after being inverted.
  • Minimal use of sensitive parts that require frequent calibration.
  • Accurate
  • Must accurately dispense the medication in correct dosages with a success rate as close as possible to 100%.
  • Efficient
  • Minimal use of moving parts.
  • Ideally, have the most direct path to solving the problem.
  • Cost effective
  • Uses the least number of motors.
  • Minimize the misallocation of expensive components to perform minor tasks.

Existing Pill Dispensers / Benchmarks:

  • Stevens Institute of Technology – Automated Home Pill Dispenser
  • Uses a corkscrew design to separate and transport pills.
  • e-pill Med-Time XL
  • This pill dispenser has 28 separate compartments to store a day’s worth of pills. It operates using a motorized disc and an audible alert. The patient is only required to shake the pills out of the device.
  • Dosages for the month need to be pre-determined and preloaded.
  • e-pill MD.2 Automatic Pill Dispenser
  • This pill dispenser also holds 28 separate cups, one per day.
  • An audio and visual alert notifies the patient that it’s time to take the medication.
  • The patient pushes the red button and a cup will come down the slide.
  • Dosages for the month need to be pre-determined and preloaded.

Existing Technologies / Research:

  • Gumball machine
  • Dispenses only one item at a time while preventing damage to the remaining gumballs.
  • Susceptible to jamming.
  • Limited to spherical objects.
  • Vending machine
  • Only works using manually loaded objects.
  • Mechanism is susceptible to jamming and damaging the product.
  • Coin sorter
  • Uses predetermined slots to separate different sized coins.
  • For our uses we adopted the idea of a slot and chute to transport the dispensed pills.
  • Paintball gun
  • Limited to spherical objects.
  • Susceptible to jamming.
  • Most reliable design requires cartridges.
  • Production bulk bin sorter
  • Uses vibration to move a single item from a bulk bin.
  • Good for asymmetrical objects of varying size.
  • Loud and requires additional complex components.
  • Vacuum
  • Loud operation.
  • May cause damage to pill coating.
  • Pills do not need to be pre-sorted.
  • Require complex plenums.
  • Complicated control system.
  • Cement truck
  • Uses a corkscrew design that separates material based on density.
  • May require a lot of space and fine adjustments to the helical structure.
  • Can cause damage to pill’s coating.
  • Pez dispenser
  • Dispenses one tablet at a time while preventing the remaining tablets from moving.
  • Requires manual loading.
  • Small range of motion and limited moving parts.

Concept Selection Process:

  • Each team member developed concepts individually to meet dispensing design requirements.
  • Concepts were shared; team members gave feedback and were evaluated in a screening matrix. The selection criteria were based off of QFD analysis.
  • Concepts were refined and optimized to produce a few hybrid designs.
  • These designs were evaluated in the Pugh matrix for our concept selection process.
  • Our final two designs are pending further refinement and component selection.

QFD

Pugh Matrix