Final Prototype
Jesse Griffith & Ryan Thomas
ABSTRACT
We worked with the Elizabeth Richardson Center, Inc. in Springdale, Arkansas, who assists physically and developmentally handicapped individuals in a variety of ways. The vocational development segment of ERC employs handicapped individuals in various tasks. The major task accomplished by the handicapped employees at ERC is the separation and packing of perforated, spiral-bound flip-books for Wal-Mart. The purpose of this project is to simplify the task for workers limited to one-hand functionality to increase their productivity. We have designed and constructed a functional electromechanical and safe device which will minimize the force and dexterity required to break the flip-books; this device retains aspects of manual operation as to not replace the handicapped worker. Ultimately, this will result in an increased paycheck for the specific individuals for which this device is designed.
BACKGROUND
Elizabeth Richardson Center, Inc.
The Elizabeth Richardson Center, Inc. (ERC) is an non-profit agency (NPA) located in Springdale, Arkansas that assists physically and developmentally handicapped individuals in a variety of ways. These ways include Childhood Education, Independent Living, Adult Education, and Vocational Development. The vocational development segment employs handicapped individuals in various tasks (1). Several handicapped individuals working at ERC possess only use of one hand. The major task accomplished by the handicapped employees at ERC is the separation and packing of perforated spiral-bound flip-books for Wal-Mart. The handicapped employees, referred to as clients, are paid on a piece rate. Consequently, the more flip-books they separate and pack, the more money they are paid. For those with the sole use of one hand this means that they will be paid less by virtue of their disability. Therefore, it is the purpose of this project to make the task less complex and more time-efficient; this will result in an increased amount of work completed, which in turn will result in an increased paycheck for these individuals.
Problem Description (Process)
At ERC, the major task performed by the handicapped individuals is breaking apart perforated, spiral-bound flip-books for Wal-Mart. Last year, ERC processed approximately 18 million flip-books, which are in use in Wal-Marts all across the continental United States.
To better understand the purpose of our proposed design, we will clarify the process through which flip-books go at ERC. They arrive at ERC in a semi-trailer from Wal-Mart and are unloaded. The load generally includes one or two of the six various sizes of flip-books that Wal-Mart uses. The six different sizes are as follows: 5” Small, 5” Large, 8” Small, 8” Large, 11” Small, and 11” Large. The final number of processed flip-books also varies with each order. After the truck has been unloaded, there is a three-step process that must be completed by the handicapped individuals at ERC. They must break apart sheets of flip-books, stack the separated flip-books into stacks of fifteen, and load the stacks into small boxes. After this process is completed, other ERC workers pack the sets of smaller boxes into much larger boxes and load them on pallets. These pallets are then loaded into a semi-trailer and sent back to Wal-Mart to fulfill the order and be used in Wal-Mart stores across the country.
Our project goal was to benefit a specific handicapped individual working at ERC. By developing this device, a profitable increase will occur regarding her flip-book processing rate. This individual only possesses use of her right hand, which greatly limits her productivity. In the course of our research and design process, however, this individual stopped working at ERC. Fortunately, there are other clients with similar disabilities who can benefit from this device. Additionally, if such a device were utilized on a larger scale, it would allow ERC to process the yearly quota of flip-books from Wal-Mart much faster, which would then enable ERC to seek additional sources of work and income for their handicapped employees.
PROBLEM STATEMENT
We have designed, constructed, and tested a fully-functional electromechanical, ergonomic, and safe device which will minimize the force and dexterity required to break the flip-books. This device is not intended to replace a handicapped worker; aspects of manual operation have been retained.
CONSTRAINTS/CRITERIA
In order to ascertain the requirements for this device, we scheduled a meeting with John Buck, Executive Director of ERC, and Lisa Mathis, Director of Adult Development. In addition to this meeting, we requested the intended end user’s production rates, as well as a video of the individual working to identify the main areas of the work process needing improvement. The following constraints were derived from this data analysis:
Functionality
• Reduces user input force to less than 20 N
• Total footprint of device must be less than 3’x3’
• Adjustable to 5 different sizes of flip-books
• Low power consumption (less than 6 Wh)
• Minimal damage to flip-books
• Low-to-no maintenance
Safety
• Isolate moving parts from user
• Isolate electrical components from user and liquids
Usability
• One-hand functionality
• Leave box-making a manual task
• Feed and eject flip-books from same side
• Keep the process centered around table height
Budget
• $500 grant ASEE-DEED (Design in Engineering Education Division) for prototype construction
DESIGN
Labeled Device Components
Design Overview
This device is made of two integrated systems, mechanical and electrical. The mechanical system is made of seven components: (A) the body, (B) the adjustable side guides, (C) the bending plate, (D) the adjustable slot, (E) the hinges, (F) the catch ramp, and (G) the plastic safety shield. The electrical system consists of seven major components: (H) a microcontroller, (I) two servo motors, (J) a pushbutton, (K) a toggle switch, (L) a 8’ 16 gauge extension cord, (M) two AC/DC power converters, and (N) the electrical housing. To operate the device, one must first set the adjustable side guides and the adjustable slot to the appropriate settings. Then one must use the toggle switch to power the device’s microcontroller. Next, place a sheet of perforated flip-books onto the top face of the body between the adjustable side guides. Then, using one hand, slide the sheet of flip-books into the adjustable slot, release, then press the operate pushbutton. The servos will actuate 180˚ bending the flip-book in the adjustable slot along its perforations and separating it from the sheet of flip-books. After actuating 180˚, the servos will return to their initial position, then rotate back 45˚ to allow the flip-book to slide from the adjustable slot onto the catch ramp which will redirect the flip-book to the retrieval space. Then repeat this process until the entire flip-book sheet has been separated.
Manufacturability
The mechanical portion of this design can be easily constructed using tools at a fabrication shop. The major components are made of 16 gauge sheet steel, in addition to 1/4″ machine screws and lag bolts of various lengths. There are few ready-built components. The hinges are the only mechanical part not available for order.
The electrical portion of this design can also be easily fabricated. Using the written Arduino code, a microcontroller can be quickly programmed. Then wires need to be connected and soldered to their corresponding pins, including wires to the servo motors, operate pushbutton, toggle switch, and power supplies. Finally the housing needs to be constructed out of Lexan and all the electrical components (minus the servos) mounted inside.
Technical Details
The mechanical portion is comprised of: 16 gauge steel sheet, 2-stainless steel surface mount 1-1/2” x 1-5/8” hinges, 1” x 2” lumber, Lexan sheets, and 1/4” x 3/4” and 1/4” x 1” nuts and bolts.
The electrical portion is comprised of: an Arduino Uno Microcontroller, 2- GWS S689-2BB/MG Heavy Duty Servos, a SPST NC Mini Momentary Pushbutton Switch, a 15 Amp SPST Toggle switch, a 6VDC 2A AC/DC Power Adapter, a 9VDC 1.3A AC/DC Power Adapter, a 8’ 16 gauge 3-prong extension cord, and 22 gauge stranded copper wire.
Cost
- Cost Breakdown of Final Prototype
Test Results of Final Prototype
• Currently we have separated two sheets of 8” Large flip-books with our final prototype. We have no more flip-books with which to test. We have contacted ERC and they will not have any more of the five sizes of flip-books that we can use to test our prototype before the semester is over. On average, this device takes one to two operations to completely separate a flip-book from the rest of the sheet. This is not ideal, but is still faster and simpler than separating flip-books with one hand. And, the flip-books suffered no damage.
• The maximum user input force has been simply reduced to the push of a button, which requires a force of less than 1 N.
• The final prototype fits within a 2’x 2’ area, which is within our 3’ by 3’ footprint constraint.
• The adjustability is present when the adjustable slot and the adjustable side guides are used in conjunction.
• According to calculations, the maximum power consumption of our device is on the order of 1.5 Wh, which is 25% of our constraint.
• We isolated the user from both the moving components and the electrical system via the safety shield and electrical housing.
• This device is completely functional for those limited to the use of one hand, and it can be equally used by either a right- or left-handed individual.
REFERENCES AND ACKNOWLEDGEMENTS
First and foremost, we would like to thank the Design in Engineering Education Division of the American Society of Engineering Educators for the $500 grant they awarded us, which provided us with the funds necessary to pursue this design project. We would also like to thank the JBU Engineering Division for supplying additional funds needed to complete our final prototype. Next, we would like to acknowledge and thank John Buck and Lisa Mathis for their support and supply of data, testing materials, and project idea. We would like to thank Dr. Will Holmes for being our professor for the spring semester of Senior Design class. We would also like to thank Dr. Kevin Macfarlan for being our professor for the fall semester of Senior Design class. We would like to thank Robert Smith for providing assistance in our fabrication and development phases. Finally, we would like to acknowledge Nance Machine and C. Mayo, Inc. for volunteering goods and services that were beyond our budgetary constraints regarding fabrication of our final prototype.
1. “About Us.” Elizabeth Richardson Center. 2011. Web. <http://www.ercinc.org/index.php/about>.
Jesse Griffith
2000 W. University St. Box #2289
Siloam Springs, AR 72761
GriffithJ@jbu.edu