Automatic Home Medication Dispenser

Project # P07009Team Guide - Dr. Daniel Phillips Project Sponsor - Dr. Michel BergTeam MembersAlan Strandburg Chris Abramo Ntongho AminGordon Yeung Nick Columbare Albert Lam

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.

• A real-time adaptive system needs to be developed.

Objective / Scope• To create a prototype home medication dispensing device that

will administer a one month course of warfarin. • The device must reliably dispense the medication in correct

dosages with a success rate as close as possible to 100%.• Device must be able to communicate with the physician via a

computer interface and relay patient’s usage information.• Device must be equipped with operating checks and alerts. • Device must be easily refilled by the pharmacist and tamper

evident.• Easy to use and simple user interface.• It was decided that tubes/trays with consistent pill orientation

would be used to increase dispensing accuracy.• A 6 stack design would be used to minimize size and

accommodate varying dosages.• A modular design will minimize manufacturing cost.

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.

QFD

Existing Technologies / Research

– Gumball machine– Vending machine– Coin sorter– Paintball gun hopper– Production bulk bin sorter– Vacuum– Cement truck– Pez dispenser

Existing Pill Dispensers / Benchmarks

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.

Round 1

Concept A - Pusher

Concept B –Tray Feed

Concept C – Rotating Slotted Disc

Concept D – Actuating Arm

Concept E – Spring Actuated Sliding Plate Pusher

Concept F – Cam Actuated Sliding Plate Pusher

Concept G – Compartmented Ring

Concept H – Helical Dispenser

Concept Screening Matrix

Round 2

Concept A1.0 – Pusher

Concept A1.1 – Puller

Concept B – Tray Feed

Concept CD – Rotary Design

Concept AD – Six Pack

Pugh Matrix

Final Two

Ranked # 1 Ranked # 2

Puller Concerns

• Violent solenoid actuation may cause shearing of pills

• Additional time and cost to design custom solenoid

• Additional cost of Soft Shift® solenoids over conventional solenoids and servo-motors.

Six Pack Design Justification

• Smoother pill dispensing• Accurate• Cost effective• Simplified balance of design• Minimal force requirement and in a single plane

Alternate Driving Option

Additional Design Consideration

Pill Follower

• Helps to maintain pill orientation within tube

• Spring• Ratcheting mechanism• Weighted follower

Alternatives to a Color Screen

• LCD with electro-luminescence backlight• LED indicators• Vacuum fluorescent display

Pill Detection Systems

• Infrared Optical Detection• Gravimetric Sensor• Mechanical Switch• Laser

Questions ? Suggestions?