Technical Report AMI-004:
Review of 2005-2006 RERC-AMI National Student Design Competition: Accessible Medication Dispensing Device
Authors: Adam Luce and Alex Leung
Coordinating Editor: Molly Follette Story, M.S.
Location: University of California-Berkeley
Current Version: 1.0 (October 2006)
Table of Contents
- Executive Summary
- Background
- Survey of Prototypes, including Summary Table of Designs
- Evaluation of Prototypes
- Recommendations
- Acknowledgement
- References
Executive Summary
For the third year, the Rehabilitation Engineering Research Center on Accessible Medical Instrumentation (RERC-AMI) sponsored the National Student Design Competition. The competition had three target design areas, one of which was an accessible medication dispensing device. Students designed the device specifically for five fictional clients with various disabilities. The device was to be moderately priced, dependable, easy to use, and capable of dispensing variable medication doses. In addition, the device was supposed to be able to slice pills/tablets into halves or quarters. Optional considerations included a quality control mechanism to monitor expiration dates, a bar code reader, a medication reminder, and a record of medications dispensed.
Background
The pharmecutical industry has grown quickly over the past several years, as scientific breakthroughs continually lead to the introduction of new drugs. For many people, taking medications is an integral and neccesary part of their day. Many patients take medications at multiple times of the day, while others must consume upwards of 20 pills or tablets per day. These factors combine with the processes of aging, which reduce some people's capacity to monitor such large amounts of medication. Improper medication administration poses serious health risks, as overdosage or underdosage can upset homeastasis and have serious detrimental effects on that person.
Many medication storage and dispensing systems are available on the market today, ranging from simple and cheap to complex and expensive. For just a few dollars, a patient can buy a weekly organizing box separated by the days of the week. Such a device requires that the patient load the pills accurately every week, and remember to take the correct pill at the correct time each day. Newer products build on the traditional organizers but add various features. These medication dispensers range in complexity and price, with some costing over a thousand dollars. Positive features include reminder systems and mechanisms to verify that the patient has taken the medication. However, these devices still rely heavily on the patient to organize the medications.
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Figure 1. Two pill storage devices: a common seven day organizer [1], and a more complex, more elaborate, and more expensive dispenser [2]
Pharmaceutical companies often offer small dosages and large dosages of the same medication for similar prices. This is because the majority of the costs arise from packaging, advertising and research and development, which stay constant with varying dosage [3]. Pill splitting has become commonplace as patients seek to reduce the soaring costs of medication. Patients who split pills can save between 23 and 50 percent per year depending on the pill [3]. Unfortunately, all the effects of pill splitting are not beneficial: it is often difficult to cut a pill exactly in half. Inaccurate pill splitting can result in improper dosage, which could pose serious health risks for the patient. Many of the pill splitters on the market require a significant amount of dexterity, which could pose a problem for elderly and disabled individuals.
Figure 2. A common pill splitter on the market [4]
Engineering design teams from ten different universities participated in this category of the National Student Design Competition sponsored by the Rehabilitation Engineering Research Center on Accessible Medical Instrumentation (RERC-AMI). In total, 22 teams from 16 different universities participated in the competition. The aims, specifications and clients of the competition are as follows [5]:
Aim: A moderately priced and dependable device that is easy to use and dispenses variable medication doses. The device may manage any one or a combination of pills, tablets or capsules.
Specs: The dispensing device must be able to slice pills/tablets into halves or quarters. Ideally, it will interpret a container's bar code, and have a quality control mechanism (including the ability to track medication expiration dates). The device should be appropriate for use in a client's home or in a clinical setting. Consider including systems to remind users to take their medications and to track what medications have already been dispensed.
Clients: Lloyd, Arnold, Dave, Wanda, Rose
Lloyd: Lloyd, a retired pharmacist, was born in 1926. Diagnosed with Type 2 Diabetes in 1989, Lloyd has poor eyesight and some hearing loss, and due to poor diet and lack of exercise, is very overweight (400lbs).
Arnold: Arnold was born in 1952 and since his heart attack in 1999 has worked in the mailroom of a large manufacturing company. He has diabetes and Parkinson's disease, and experiences slight to moderate tremors. He lives alone.
Dave: Now 22, Dave was diagnosed with diabetes in 2000. He has limited use of his right arm and leg due to a head injury he sustained while playing football in college. Dave uses a cane and sometimes an electric scooter.
Wanda: Born in 1994, Wanda has low vision and diabetes. Wanda weighs 80 lbs. She is being encouraged to start administering insulin to herself, as her mother recently passed away and her live-in grandmother, Rose, is blind.
Rose: Born in 1941, Rose is blind and was recently diagnosed with lung cancer. With the recent death of her husband, Rose is about to move in with her daughter and son-in-law and her granddaughter, Wanda, but she wants to maintain her independence as well as help out around the house as much as she can.
More information on these fictional clients and rules for the 2005-2006 competition can be found online (see: http://rerc-ami.org/ami/projects/d/2/2/year3/). Each team was given a maximum design and prototype fabrication budget of $2,000.
Survey of Prototypes
The Product Table compares nine of the submitted device designs on various features found in the devices. (Due to lack of information, the team from Texas A&M could not be included in the evaluation.)
The University of Akron designed a device that uses motors to turn discs to dispense the pills. This method of dispensing through rotating canisters is simple and reliable with a disk system that uses a computer program to aid in the dispensing of pills. Several canisters are included in the design, one for each medication. In this way the need for sorting pills manually is eliminated. The computer software guides the patient through the process, telling him or her where to load the pills. The computer program allows the patient to program when to take the dosage, what the dosage is, and how many times a day to take the dosage. The computer allows users to track their medication usage. Also, if the dosage is changed for a given medication, the patient only needs to change the schedule in the computer program. Through a barcode system, it is possible to keep track of expiration dates as well [6].
Figure 3. The AMP 1.0 from University of Akron [6]
Columbia University designed a very professional prototype, the MedX. It has a patient recognition system, a dispenser and a splitter. The device could be used either for personal use or in a clinical setting. The team points out that because the system is modular, more dispensers could be added for use in a clinical setting. Patients are recognized through a barcode reader, and so a patient only needs to hear the alert that medication is ready and swipe their barcode to receive their dosage (once the information was entered into the database). Columbia was one of the only teams to tackle the cutting and dispensing of pill quarters into their design. As a prototype, MedX offers the possibility to split, organize, prepare, store and dispense medication for multiple patients [7].
Figure 4. The MedX from Columbia University [7]
The team from the University of Wisconsin-Madison designed the Daily Dose, which focused on accessibility and usability. The Daily Dose uses a rotating drum system, in which each drum is fitted for a particular pill shape. There is a touch-sensitive LCD screen which is high contrast and high resolution. The patient is walked through the pill loading protocol via the touch screen. The Daily Dose allows for pill scheduling, complete with a reminder and alarm system. Also included is a medication tracking system. Stored pills are protected from UV light and humidity. The team also took into account security concerns to prevent unauthorized use. Among the many accesible design features are the large print and easy pill loading [8].
Figure 5. The Daily Dose from University of Wisconsin-Madison [8].
The University of Rochester designed a product, the Dex, that couples with a computer and has a clever user interface to dispense medication. The Dex requires a loader to stock the device. The computer program allows for extra instructions such as "take with water" to be added, in addition to pill scheduling and alert systems. The Dex also can track expiration dates. To retrieve medication, a patient only needs to put a cup in the dispensing area against a low pressure switch. The dispensing mechanism is a relatively complex conveyer system. The team invisioned incorporating a PDA into the device for a commercial product in place of the laptop they used in the prototype. The team also modified a commercial pill splitter to make it more accessible and to accompany the Dex [9].
Figure 6. The Dex from the University of Rochester [9]
The team from the University of Connecticut created a fully automated device that keeps track of information about the medication being dispensed, the number of pills remaining, expiration dates and pill scheduling, and has an alarm system and built-in pill splitter. The device is easily loaded by simply pouring medication into the device, can hold several medications, and is capable of dispensing and cutting tablets of all shapes and sizes. The device also includes a barcode scanner to avoid input errors by the patient. The mechanism of dispensing is relatively complicated, consisting of a clever robotic arm for transfer of pills. A vaccuum tube is mounted on the robotic arm, which contains a pressure sensor to ensure a pill is being dispensed. This is one of the only teams that addressed the cutting and dispensing of quarter pills. The software is run on a laptop, but students point out that the software could be run on a microcontroller and a touchscreen, resulting in lower costs [10].
Figure 7: The AMD from University of Connecticut [10]. Numbered parts include: 1. Storage Modulus, 2. Pill Compartments, 3. Robotic Arm, 4. Vertical Arm Servo Motor, 5. Horizontal Arm Servo Motor, 6. Compartment Servo Motor, 7. Cutter, 8. Blade, 9. Pill Positioner Servo Motor, 10. Blade Servo Motor, 11. Cutter Funnel, 12. Pill Drop Servo Motor, 13. Robotic Arm Tip, 14. Positioner, 15. Connector Cable, 16. Chute to Cutter
The University of California-Santa Barbara created a dispenser based on the design of a current shampoo dispenser. The design included reminders for medicine, and three separate pill compartments. Using this device, a patient would load medication into separate boxes and stack those boxes inside the device. When the alarm went off, the patient would go to the device, pull out the correct drawer, and take out the box that he or she had loaded previously. This design had relatively few features compared with the other devices.
The University of California-San Diego designed a very clever pill splitter, but neglected the dispensing side of the design brief. The device is a very accurate pill splitter with easy loading. The patient needs only to pour the pills into the device, and by pushing down on the top, a pill is cut in half and dispensed at the bottom. Though only one pill is cut at a time, the patient can press the top of the device many times to cut many pills. Only a small force is required, and the device is easily portable. The cutting mechanism is fully contained inside the device, so safety is not an issue [11].
Figure 8. Device from University of California-San Diego [11]
The University of North Carolina added a cutter to a modified commercial 28-slot dispenser. Using this device, the patient enters the time of day and sets alarms for the medication. When the time comes to take a medication, the device gives an audible alert and dumps the pill(s) into a cup. The team included a pill cutter with safety guards, meant to be be used on top of the loading tray of the device. In order to dispense medication, the 28-slot dispenser is stored upside down in the box with an opening in the lid equal to the size of one medication compartment. When it is time for the client to take his or her medication, the dispenser will move so that one compartment is over the opening in the lid and the contents are dropped into a cup below [12].
Figure 9. The EMOD from University of North Carolina [12]
Vanderbilt University designed a pill splitter and dispenser using a modified electric nail gun. The prototype is rather large, and concentrates on pill splitting rather than dispensing. The prototype is a single pill type design, so that a separate mold is required for each pill shape. The device has exposed blades and does not take the clients' disabilities into account. The mold is loaded with several pills in a linear fashion, and they are run through the machine, cut one at a time, and dispensed on a ramp that extends out one side. The prototype has low pill splitting accuracy, with about 30% of pills being only partially cut [13].
Figure10. Vanderbilt University’s Pill Pusher 9000 [13]
Evaluation of Prototypes
In June of 2006, nine judges were assembled to evaluate the designs of all three categories and to give out awards for first through third place in each category. The University of Connecticut's Accessible Medication Dispensing Device won first place in the pill dispensing category and was also named the overall winner of the competition. Strengths of this design are its many dispensing features. Though the robotic arm mechanism is complicated, the design is original and worked successfully as a prototype. The device also included a user friendly program to facilitate use of the device. The second place winner was the Dex, from the University of Rochester. The strengths of this device were its completeness, the testing done, task repeatability and the easy-to-use computer software. The third place design was the Daily Dose by the University of Wisconsin-Madison. The strengths of this device included the simplicity of the rotating drum dispensing system, the testing done, and the special attention paid to the usability aspects of the design.
Recommendations
The teams fulfilled the requirement of the competition to varying degrees. The products had different strengths, and some teams concentrated on different aspects of the problem than others. On the minimal end, UC-San Diego made a very complete, well-designed pill splitter, which would hold up and did hold up to a commercial splitter in testing. The winner of the competition, the University of Connecticut, had a very complete product with virtually all the features one could ask for in a pill dispenser and dispenser. The University of Rochester designed a versatile computer program, which smoothly led the client through use of the device. The Daily Dose from UW-Madison excelled in usability and had a clever rotating drum method of dispensing. One could combine the strengths from the various devices to make up for the various shortcomings and put together a very marketable pill dispensing and cutting device The pill splitter from UC-San Diego may already be on its way to the market, as the students from this team expressed plans to apply for a provisional patent and investigate whether or not there is commercial interest in their device. Such a design could be incorporated into a larger pill dispensing device as well.
As pointed out by many of the teams in their reports, an optimal design would depend heavily on cost. Depending on what features were necessary for a given client, the optimal design might change, as excessive features could lead to excessive costs. For the clients in this project, an optimal design would probably include several features, including: a user-friendly interface to navigate the device, pill scheduling, an alarm system, security features such as a thumbprint device, voice recognition system, or simply a password, expiration date tracking, a memory of medications dispensed, capacity to store and split many pill types, easy loading, automated pill splitting and, of course, easy dispensing.
It may be possible to combine key components from the various devices to make an optimal design. For dispensing, the rotating drum from University of Wisconsin-Madison could be used for its simplicity and manufacturability; and for loading, this same design could be included, for its usability and ease of loading. For a computer program, the design from University of Rochester could be included for its flexibility and ease of use. An optimal device might also include a touch-screen and a voice-guided dispenser, as well as a cup-dispenser, which was present in a few of the devices. A pill splitter should also be present in an optimal design, perhaps through the incorporation of the UC-San Diego design, or a design more similar to the clever University of Connecticut splitter. Through such mixing and matching of the best features of several teams' submissions, a very complete and original product could be developed.
Acknowledgment
This work is supported by the Rehabilitation Engineering Research Center on Accessible Medical Instrumentation, funded by the National Institute on Disability and Rehabilitation Research, U.S. Department of Education Grant #H133E020729. All opinions are those of the authors.
References
[1] Weekly Pill Organizer. Retrieved 21 Sept. 2006 from: http://www.productsforseniors.com/proddetail.asp?prod=HEA383.
[2] e-pill. "Pill Dispenser." Retrieved 21 Sept. 2006 from: http://www.epill.com/dispenser.html.
[3] Fischman, Josh. "Rx: split decisions." USNews.com, 2004. http://www.usnews.com/usnews/health/articles/040531/31pill.htm.
[4] MaxiAid. Retrieved 21 Sept. 2006 from: http://www.maxiaids.com/store/prodView.asp?idstore=4&idproduct=3097&idCategory=247&category=Splitters/Crushers&product=Safety_Tablet_Cutter
[5] "Student Design Competition." 2005. RERC-AMI. Retrieved 14 Sept. 2006 from: http://rercami.org/ami/projects/d/2/2/year3/.
[6] University of Akron. Retrieved 14 Sept. 2006 from: http://gozips.uakron.edu/~alw12/.
[7] Columbia University. Retrieved 14 Sept. 2006 from: http://www.columbia.edu/~jcz2002/CHI/.
[8] University of Wisconsin, Madison. Retrieved 14 Sept. 2006 from: http://www.theamdd.com/index.html.
[9] University of Rochester. Retrieved 14 Sept. 2006 from: http://www.industrialnewyork.com/dex/.
[10] University of Connecticut. Retrieved 19 Sept. 2006 from: http://www.bme.uconn.edu/bme/sendes/Spring06/Team6/index2.html.
[11] University of California, San Diego. Retrieved 19 Sept. 2006 from: http://www.ucsdrerc.com/index.php.
[12] University of North Carolina. Retrieved 19 Sept. 2006 from: http://www.unc.edu/usr-bin/scerbos/pilldevice/index.php.
[13] Vanderbilt University. Retrieved 19 Sept. 2006 from: http://www.bme.vanderbilt.edu/srdesign/2005/group14.