Paper ID #24835

Senior Design Project – A Road from the Initial Design to a Working Proto-type

Dr. Vladimir Genis, Drexel University

Dr. Vladimir Genis - Professor and Head of the Department of Engineering Technology in the College ofEngineering, has taught and developed graduate and undergraduate courses in physics, electronics, nan-otechnology, biomedical engineering, nondestructive testing, and acoustics. His research interests includeultrasound wave propagation and scattering, ultrasound imaging, nondestructive testing, biomedical engi-neering, electronic instrumentation, piezoelectric transducers, and engineering education. Results of hisresearch work were published in scientific journals and presented at the national and international confer-ences. Dr. Genis has five US patents. As a member of a supervising team, he worked on the developmentof the curriculum for the ”Partnership for Innovation in Nanobiotechnology Education” program. Dr.Genis is a Fellow of the American Society for Nondestructive Testing.

Mr. M. Eric Carr, Drexel University

Mr. Eric Carr is an Instructor with Drexel University’s Department of Engineering Technology. A grad-uate of Old Dominion University’s Computer Engineering Technology program and Drexel’s College ofEngineering, Eric enjoys finding innovative ways to use microcontrollers and other technologies to en-hance Drexel’s Engineering Technology course offerings. Eric is currently pursuing a Ph.D in ComputerEngineering at Drexel, and is an author of several technical papers in the field of Engineering TechnologyEducation.

Sarina M. Stoor, Arora Engineers Inc.

Project Coordinator at Arora Engineers, Inc.

Mr. Fahad Ibrahim AlsuhaibaniAlexander M. Rogers, Drexel University

c©American Society for Engineering Education, 2019

Senior Design Project –

The Road from Initial Design to Working Prototype

Abstract

The Senior Design Project is the capstone undergraduate experience for Drexel University’s Engineering Technology (ET) students. During this real-world engineering project, students see projects through from the design and development stage to the production of a working prototype in consultation with their faculty advisors. Initially, a group of students has to select a project and form a working team of four (based on students’ knowledge, experience, background, and personal preferences) as well as an advisor (or advisors). The topic of this particular project was “Low - Frequency Pulsed Electromagnetic Field (PEMF) Device For Therapeutic Applications”. The main goal of this project was to develop a new, low frequency PEMF device based on existing research, while upgrading it to include new technologies and functionality. These improvements included more advanced controls, including modernizing the user interface with a microcontroller and a graphical user interface (GUI), allowing easy user customization of the PEMF parameters. Multiple criteria and testing parameters were created in order to ensure the safety, effectiveness, functionality, and accuracy of the device. Three 11-week terms were devoted to the research, development, and testing of this device, which required precise planning during each stage of the project. Funding for this project was the responsibility of the group; however, several corporations provided in-kind support. The oral presentation and the final written report were evaluated by the assessment committee comprising ET faculty and industry representatives. The completed working prototype was registered with the university’s Technology Commercialization office. Introduction The Senior Design Project for engineering and engineering technology students of Drexel University is a three-term, nine-credit experience that students take during their senior year. The senior design project is a capstone experience, in which students select a topic in consultation with their advisor according to a department’s guideline. The course objective is to train students to execute a project from initial conceptual design to the final design completion, to conduct design reviews, and to document and present the findings and conclusions in both oral and written formats. Students are also required to build a working prototype of their final design concept and present it during final presentation of the project. Upon completion of this project, the students gain experience and expertise in solving real-world design problems and communicating their results in a professional format. The following topic, among others, was introduced to the engineering technology students: “Low Frequency Pulsed Electromagnetic Field Device For Therapeutic Applications”. The group of four students chose this topic for their Senior Design Project. The experience and results of the

group (Fahad Alsuhaibani, Ivo Krakic, Alexander Rogers, and Sarina Stoor) is described in this work. Within the frame of this project, students designed and developed a working prototype, evaluated and adjusted final parameters, described the project in their pre-proposal, progress report, and final report, and presented the developed prototype to the assessment committee comprising ET faculty and industry representatives. The main goal of the project was to develop a new, low frequency PEMF device based on existing technology, while upgrading it to include new technologies and functionality. These improvements were intended to incorporate more advanced controls – modernizing the user interface using a microcontroller and a graphical user interface (GUI), allowing easy customization of the PEMF parameters.

Although this device was initially intended to help those with soft tissue tears and bone fractures, it can also can be used to relieve muscle soreness and tightness. This device will be able to help a wide range of individuals and reduce the limitations in everyday life caused by back problems. The final device uses proven pulsed electromagnetic field therapy techniques which have been demonstrated to be safe and effective for human use [1]. The following procedural steps were undertaken by the students during the described Senior Design Project:

1. Formation of the team 2. Project and advisor selection 3. Literature survey 4. Creation and presentation of the design proposal 5. Cost and budget analysis 6. Design and development of the device 7. Laboratory testing of the developed device (and corrections if necessary) 8. Final presentation

Rationale of the project.

Low back pain is a very common health problem in the general population and one of the most common reasons people seek medical treatment. It is expected that between 60% and 80% of the world population will experience low back pain during their lifetime with 65% of these cases being recurrent. Low back pain can be caused by different etiologies, such as muscle or ligament strains, herniated discs, arthritis, alteration in the curvature of the spine or osteoporosis related fractures [2].

PEMF technology has been around for decades and has been used to heal bone fractures, treat psychological disorders like depression, reduce swelling and pain, promote blood circulation, and stimulate the immune system. Doctors, psychiatrists, chiropractors, naturopaths, and veterinarians use PEMF devices in their practices [3], [4].

Musculoskeletal injuries can be treated using invasive and non-invasive methods. Both invasive and non-invasive methods usually include prolonged immobilization of the injury, which may lead to delay in the recovery [5], [6]. It has been scientifically proven that Pulsed Electromagnetic Field (PEMF) therapy decreases the immobilization period by mimicking the body’s natural healing process, which increases the blood flow to the injured area to speed up the healing process.

PEMF therapy devices use electromagnets to direct a series of magnetic pulses through damaged tissue in order to stimulate cellular repair. The body’s natural healing process is accelerated by utilizing this mechanism [7], [8]. The intent of PEMF therapy is to reduce the pain of the injured area and to speed up the healing process.

The group looked into current PEMF devices on the market and found that many are expensive and outdated. A new, affordable, low frequency PEMF device was developed utilizing new technologies. These new technologies include more advanced controls, modernizing the user interface with a microcontroller and a graphical user interface (GUI), as well as allowing flexible customization of the PEMF parameters. The developed device has one coil in the back of the belt and strictly utilizes low frequencies. The developed device has several advanced features, such as multiple frequency options, an automated timing system, and an easy-to-use touchscreen. This allows the user to be able to move freely during treatments and adjust parameters as needed.

Criteria As a device intended for human use, two major criteria must be verified and tested. These criteria are safety and efficacy. It is essential that the device be designed in such a way that it cannot cause harm to the user when operated in a reasonable manner. The magnetic fields (~35 mT peak) generated by this device do not pose any danger. Short-term exposure to field strength levels of up to 50 mT have been shown to have no discernible adverse effects on humans [9] and have been shown to have potential therapeutic properties. Similarly, the voltages involved are considered safe for casual human contact (supply voltage from the battery pack is roughly 12 VDC.) As an additional precaution, all electrical connections are insulated from casual user contact. The selected power source is a "3S/2P" (three in series; two in parallel) configuration of six LG HE4 Lithium-Ion batteries. As this is a prototype device, a commercial 18650 cell charger was utilized for charging cells. A battery-management board could be added to a production model without any significant changes to the design, in order to allow for convenient, in-device charging. Inadvertent discharge of the battery pack was prevented by thoroughly insulating the battery terminals. In addition, an inline fuse was installed to ensure user safety in the event of a short circuit. This fuse is mounted as close as practicable to the positive terminal of the battery pack.

Since the device is intended to be worn, ergonomics is another important design criterion. To be effective, the device must be comfortable to wear for the expected duration of therapy sessions (15-20 minutes). Functionally, the device is capable of producing the desired output: a pulsed electromagnetic field with a maximum peak strength of 35 mT, with the capability to vary the duty cycle and frequency from a user-friendly control interface built into the device. The user interface has two modes: Easy Mode (where the user selects a desired preset therapy) and Advanced Mode (allowing the user to customize intensity, frequency, duration, and duty cycle). The prototype of the PEMF device is presented in Figure 1.

Figure 1. Prototype of the PEMF device. While designing the controller, the primary goals were the accuracy of the controlled parameters, user-friendly interface, and modernization of current technology. To achieve these goals, the controller was designed around the Arduino Mega 2560 board which allowed for easy control of the touch screen and other device parameters. Various duty cycles were evaluated in order to determine the most efficient pulse for the portability of the device. Another benefit of using Arduino was that it supported touchscreen technology without requiring more complex technologies. The user interface consists of three menu options (soft tissue injuries, bone fractures, and advanced settings). Under the soft tissue injury and bone fracture selections, there are predetermined parameters set for time and field strength dependent on the severity of the injury. The advanced option allows the user to select frequency and magnetic field strength manually. Several prototypes of the coil were evaluated and tested. The main design criteria for the coil were the required magnetic field (up to 35 mT) and weight, since the coil is placed on the back embedded in the belt. The belt was donated by Old Bones Therapy upon the students’ request and has a pocket where the coil was placed (Figure 2).

Figure 2. The belt provided by Old Bones Therapy.

The coil was tested with and without a central iron core. After having tested several coil configurations, the final circumference of the coil ended up being 22 centimeters, using 180 feet of AWG 18 magnet wire producing 218 turns and a soft iron core (Figure 3). This design allowed to increase the magnetic field to 4.5 mT per amp. Therefore, the required 35mT design value of the magnetic field can be achieved with 7-8 A of current; the coil temperature was measured to be roughly 80 degrees Fahrenheit after 15 minutes of treatment at full power.

Figure 3. Coil with soft iron core. Testing the Prototype For the testing and evaluation of the PEMF device, a simple experimental setup consisting of the Arduino, coil assembly, a power supply, and a magnetometer were utilized. The main purpose of the testing was to determine what parameters were needed to achieve the desired magnetic field strength as measured just above the center of one end of the coil. This provided data for electrical design of the PEMF prototype to evaluate coil temperature and battery life. A MEMS magnetometer attached to a 3D printer gantry was used to scan the surface of the electromagnetic coil while it was powered at a 2 mm x 2 mm resolution. The test was conducted at 1 A current and provided data about the magnetic field in the X, Y, and Z directions. Using the resulting data, a color-coded visualization of the magnetic field was produced (Figure 4) and showed magnetic field strength on the order of 30-40 mT would be produced at roughly 4 A current. This matches the design target of 35 mT.

Figure 4. Visual representation of the magnetic field produced by the coil. X-axis is represented

by red, Y-axis is green, Z-axis is blue/orange.

To test the coil, the experimental setup was as follows: The electromagnetic coil was placed on a table with its leads connected to a laboratory power supply. To measure the magnetic field generated by our coil, we have made use of three different magnetometers: a laboratory-grade Bell digital magnetometer, a MEMS magnetometer, and a cell phone’s internal magnetometer. Comparing the results of the different magnetometers allowed us to validate the data. Each magnetometer was placed directly above the center of the coil. The current was gradually increased while recording the readings from each magnetometer. From this data, we could determine the magnetic field that was produced by the coil for any given current. In addition to measuring the output magnetic field, this experimental setup was utilized for measuring of the coil’s resistance and its temperature. To measure the coil resistance, a four-terminal sensing, also known as Kelvin sensing, was used for better accuracy. To test the temperature of the device, a thermocouple was placed within the electromagnetic coil during a treatment program. This test showed a maximum temperature of about 35o C internally (Figure 5). The surface of the coil was observed to be several degrees cooler.

Figure 5. Thermocouple Temperature Testing

Various frequencies, waveforms, and duty cycles were tested in order to determine optimal treatment parameters.

Budget and Schedule

There are several companies currently producing PEMF devices; the price range of these devices is between $1,500 and $20,000. These devices are mainly sold to orthopedic doctors, physical therapists, and adults who suffer from back pain or other soft tissue or bone ailments. This market can be expanded to target athletes and athletic departments within schools and universities. According to publicly released information by leading companies in the market, PEMF devices have a market size of $500 million [10]. One of the leading companies in the market is Orthofix International NV, which has a 32% share of the PEMF devices market. These companies have a competitive advantage over new entrants, which gives them the capability to ask a premium for their products.

The students anticipated that the device would have a retail price of $600, which is significantly lower than the $1,500 market starting price, potentially attracting customers, especially in the early stages. The students’ business plan envisioned entering the market locally in the Delaware Valley area. In year one, they anticipated selling to local physical therapy offices and universities’ athletic trainers.

After having established local marketing connections, the students planned to expand to cover northern New Jersey in year two, and projected that they would have clients in the Northeast and Mid-Atlantic markets by the end of year four. The students’ partnership with Old Bones Therapy, who have provided the therapy belts used as part of the product design, should allow the establishment of a network in the San Francisco Bay Area by year five. After having been in the market for five years, the students expected to have a higher volume of online orders from online retail stores such as Amazon. Economic Analysis When the group of students chose this project at the beginning of the fall quarter, they had an estimated total cost of $500 to complete the project. During the preliminary research in the fall quarter, the group compared various options and prices. As a result, the group was able to eliminate unnecessary expenses and ended up with an estimated cost of $200 to complete the senior design project. Students also were able to secure funding from Old Bones Therapy that provided the group with in-kind donation of straps (belts) totaling $120. This allowed for reduction of the cost to $80.

In the winter quarter, the group added a few items to the design, which increased the total costs to $125.37. In addition, students managed to secure $1,000 in funding from winning the Botstiber Senior Design Entrepreneurship Competition, which they utilized to enhance the development of the senior design project and learn principles of entrepreneurship. The bill of materials needed to complete a single PEMF therapy device is presented in Table 1.

Table 1. Project bill of materials

Item Supplier Quantity Cost per unit Cost

Arduino Mega 2560 Amazon 1 $11.98 $11.98

Back Belt Old Bones Therapy

4 $29.95 $119.80

Sponsored 4 $0.0 $0.0

Copper Wire Amazon 1 $16.73 $16.73

3.5" LCD/TFT Display Amazon 1 $44.27 $44.27

12-bit DAC module Amazon 1 $7.91 $7.91

AKOAK 15 amp Diode Axial Amazon 1 $6.99 $6.99

DZS Elec 12A DC-DC Step Down Buck Converter

Amazon 1 $10.99 $10.99

Cast Iron Rod Amazon 1 $26.50 $26.50

Total cost: $125.37

Considering commercialization of this project, the manufacturing cost in mass production is anticipated to be $150.84 per unit. To achieve acceptable profit margins including additional associated costs, such as storage, dealer’s profit, logistics, etc., the retail price of the developed product should be about $600 per unit. Using a Net Present Value model (NPV) and a projected sale of 50 units in year one with a 100% increase in sales each year for the first 5 years, taking into consideration a rate of 2% inflation, the group plans on attaining a total profit of $320,000 by the end of year 5 (Table 2).

Table 2. Five year profit projection

Year 1 Year 2 Year 3 Year 4 Year 5 Total

Units Sold 50 100 200 400 800 1550

revenue $30,000.00 $60,000.00 $120,000.00 $240,000.00 $480,000.00 $930,000.00

Cost with added 2% inflation

-$5,652.84 -$11,762.43 -$24,964.77 -$54,045.34 -$119,340.84 -$220,994.21

Labor -$2,000.00 -$4,000.00 -$8,000.00 -$16,000.00 -$32,000.00 -$62,000.00

Tax @ 35% -$10,500.00 -$21,000.00 -$42,000.00 -$84,000.00 -$168,000.00 -$325,500.00

Profit $11,847.16 $23,237.57 $45,035.23 $85,954.66 $160,659.16 $321,505.79

Schedule

The group began this project at the end of the summer in 2017 by choosing teammates and picking a project topic that interested everyone in the group. After choosing a topic, students approached two faculty to be advisors. Then, the group started working on a pre-proposal for the project which should be submitted for an oral presentation at the end of the fall quarter. The majority of the fall term was spent on research related to existing PEMF technology and gathering material for the project. By the end of the fall term, the group began building the first iteration of the user interface (UI).

Term-by-term activities are presented below. Fall term: During the fall term, students spent time primarily on the research of PEMF therapy and its current applications for treatment various soft tissue and bone fracture-related ailments. This information fueled the project. Multiple publications on this topic were collected and analyzed. Research was also conducted on the types of safe materials that would be efficient and economical for the project including a belt, a coil, and associated electronics. Students came up with the conceptual design and block diagrams for the prototype that was built during the winter term. Important milestones in the fall included defining the problem and the need for the said device along with identifying the criteria for a successful device and the constraints on the solution. The proposed schedule was provided to the advising faculty. Winter term:

Design and development of the prototype was the major component of the project. Most of the time was allotted for design, construction, and testing the prototype. The major milestone in the winter term was to have a working prototype that has been tested successfully for functionality by the week six of the term. The goal was to have the final prototype ready for the final presentation in the spring. The first iteration of the UI was completed by December 2017 and the power circuit was completed by the end of January 2018. Once the UI and power circuit were completed, all electrical components were incorporated with the belt and tested. The completed working prototype was finished by the end of February 2018. Necessary documents and test data were generated, and the students revised the design report according to their advisor’s comments. The written report and the oral PowerPoint presentation were completed on time.

Spring Term:

Although the group planned to have the final prototype completed by the end of the winter term, time was allotted for final adjustments and testing of the prototype during the spring term. During the spring quarter, students modified the controller and finalized product testing. Students also performed a thermal analysis that confirmed that the coil is safe for the user. Finally, much of the spring term was devoted to preparation of the final report as well as the oral presentation, which took place during the eighth week of May 2018. During the presentation, students successfully demonstrated a working prototype of the developed device. The belt was worn by one of the members of the team who demonstrated the functionality of the controller for manipulating required parameters (Figure 6).

Figure 6. Students demonstrate the completed working prototype

The completed working prototype was registered with the university’s Technology Commercialization Office.

Specific tasks of the project management are presented in Table 3. 1 and table 3. 2.

Table 3. 1. Project Management Schedule

Task Name Start Finish Days Topic Selection 2017-08-10 2017-09-01 22 Write Pre-Proposal 2017-09-04 2017-09-14 10 Complete BOM 2017-09-15 2017-10-09 24 Identify Sponsors 2017-10-10 2017-10-12 2 Order Parts 2017-10-13 2017-10-16 3 Create Presentation 2017-10-17 2017-10-19 2 Build user interface 2017-10-20 2018-01-02 74 Finalize fall reports 2017-10-20 2017-11-30 41 Build power circuit 2018-01-03 2018-01-30 27 Assemble Prototype 2018-01-31 2018-02-27 27 Finalize winter reports 2018-02-28 2018-03-16 16 Enhance controller 2018-03-19 2018-05-04 46 Complete testing 2018-05-07 2018-05-16 9

Table 3. 2. Gantt Chart

Senior Design Project Evaluation and Assessment The Senior Design Project three-term course sequence has been designed with educational objectives and learning outcomes based on the general criteria provided by ABET for engineering technology programs. Multiple assessment measures have been implemented and documented to demonstrate that the course objectives and outcomes are being met. A formative evaluation assessed initial and ongoing project activities based on the students’ written reports and oral presentations during fall and winter quarters. A summative evaluation assessed the quality and impact of an implemented project based on the students’ final reports and oral presentations during the spring quarter. The assessment committee comprises ET faculty and industrial participants. Each member of the committee is provided an assessment form separately for the written report and the final presentation. Based on the 2018 ABET outcomes (a to k) the sample of the assessment sheet, which represents a portion of the assessment form is presented below.

5 4 3 2 1 N/A

Outcome a. /Performance Indicator 1. Demonstrates ability to apply knowledge of the discipline.

☐Can demonstrate comprehensive knowledge of the discipline with rare mistakes or errors.

☐ ☐Can demonstrate knowledge of the discipline with few mistakes or errors.

☐ ☐Often has difficulty demonstrating basic knowledge.

☐

5 4 3 2 1 N/A Outcome a. /Performance Indicator 2. Demonstrates mastery of the techniques and skills of the discipline.

☐ Can demonstrate comprehensive mastery of the techniques and skills of the discipline with rare mistakes or errors.

☐ ☐ Can demonstrate mastery of techniques and skills of the discipline with few mistakes or errors.

☐ ☐ Often needs help when demonstrating skills used in the discipline.

☐

5 4 3 2 1 N/A Outcome a. /Performance Indicator 3. Demonstrates mastery of modern tools used in the discipline.

☐ Can demonstrate comprehensive mastery of modern tools used in the discipline with rare mistakes or errors.

☐ ☐ Can demonstrate mastery of modern tools used in the discipline with few mistakes or errors.

☐ ☐ Often needs help when demonstrating skills used in the discipline.

☐

5 4 3 2 1 N/A Outcome b. /Performance Indicator 1. Demonstrates an ability to apply a knowledge of mathematics to engineering technology problems.

☐Can demonstrate comprehensive ability to apply a knowledge of mathematics to engineering technology problems with rare mistakes or errors.

☐ ☐Can demonstrate an ability to apply a knowledge of mathematics to engineering technology problems with few mistakes or errors.

☐ ☐Often needs help to apply a knowledge of mathematics & computer programming to engineering technology problems.

☐

5 4 3 2 1

Grading Normalized Scale ≥ 90% ≥ 80%

<90% ≥ 70% <80%

≥ 60% <70% < 60%

Each member of the assessment committee writes the score that best represents evaluation of each Outcome/Performance Indicator. Based on the total average score, the best senior design project is chosen to represent the department in the College of Engineering senior design project competition, which includes participants from all engineering departments. Conclusion The Senior Design Sequence is a capstone experience which provides students the opportunity to apply their knowledge and skills gained in the previous years of coursework [11]. It is the most important challenge of the senior year. This three-term sequence stimulates students’ interest in engineering and engineering technology. It also demonstrates students’ technical competence and ability to work in teams and to communicate orally and in writing on the progress and results of the project. During the fall term, the students formed a team, selected a project and advisors, and submitted the pre-proposal, which was approved by the team’s advisor and the School’s Senior Design Committee. Emphasis was placed on the problem and its solution, not on the technologies that were used by the team. During the winter term, the students revised their design progress report and began implementation of the project. By the end of this term, students had demonstrated the functionality of the prototype and made necessary modifications according to their advisor’s recommendations. At the end of the term, the team made a 20-minute presentation on their progress to the advisor and Senior Design Committee representatives. In the spring term, the team completed the project, conducted the final tests of the functionality and safety of the developed prototype, and prepared the final report and presentation. During the eighth week of May, the project was presented to the ET Assessment Committee and received the second place among all ET projects. The completed working prototype was registered with the university’s Technology Commercialization office. References

[1] PEMF Safety. DrPawluk.com. October 10, 2017. https://www.drpawluk.com/education/pemf-information/pemf-safety/. Accessed November 15, 2017. [2] Renato Andrade, Hugo Duarte, Rogério Pereira, Isabel Lopes, Hélder Pereira, Rui Rocha, and João Espregueira-Mendes. Pulsed electromagnetic field therapy effectiveness in low back pain: A systematic review of randomized controlled trials. Porto Biomedical J. 2016, 1 (5), pp. 156-163. [3] https://magdahavas.com/dr-oz-on-pemf-therapy-and-pain-control/. Accessed October 21, 2018.

[4] Arthritis, Osteoporosis, and Chronic Back Conditions. Arthritis, Osteoporosis, and Chronic Back Conditions | Healthy People 2020. https://www.healthypeople.gov/2020/topics-objectives/topic/Arthritis-Osteoporosis-and-Chronic-Back-Conditions. Accessed November 29, 2017.

[5] Khan, K. M., and A. Scott. Mechanotherapy: how physical therapists' prescription of exercise promotes tissue repair. British journal of sports medicine. April 2009. https://www.ncbi.nlm.nih.gov/pubmed/19244270. Accessed October 24, 2017. [6] Szczesny, S. E., C. S. Lee, and L. J. Soslowsky. Remodeling and repair of orthopedic tissue: role of mechanical loading and biologics. American Journal of Orthopedics. November 2010. https://www.ncbi.nlm.nih.gov/pubmed/21623418. Accessed November 14, 2017. [7] W. J. W. Sharrard. A Double-Blind Trial Of Pulsed Electromagnetic Fields For Delayed Union Of Tibial Fractures. Journal of Bone and Joint Surgery. Vol. 72-B, No. 3, pp. 347-355, 1990. [8] Fracture Healing. Orthobullets. https://www.orthobullets.com/basic-science/9009/fracture-healing. Accessed October 16, 2017. [9] ICNIRP Guidelines For Limiting Exposure To Time-Varying Electric and Magnetic Fields (1 Hz–100 kHz). Health Physics 99 (6): 823, 2010. https://www.icnirp.org/cms/upload/publications/ICNIRPLFgdl.pdf. Accessed November 19, 2018. [10] Orthofix International N.V. News release. http://www.jefferies.com/CMSFiles/Jefferies.com/files/Orthofix%20v9.pdf. Accessed November 30, 2017. [11] V. Genis. Senior Design Project in Biomedical Engineering Education. Proceedings of the ASEE Annual Conference, pp. 1-9, 2007.