MEGR2156webpage

Prologue:

September 8, 2018: Wendy Martinez, a 35-year-old female jogger was attacked and killed in Washington, DC. Mollie Tibbets, a 20-year-old female jogger, was attacked and killed in Brooklyn, IA and found dead on August 21, 2018. A 37-year-old female was attacked while running in Bridgewater, MA. She manages to fight off her attacker. A High School female student attacked in her own neighborhood while training for cross country. She managed to escape. May 2018: My own friend harassed to the point of running to my front door for help while on a training run. Luckily, I was home. This month: My neighbor returned home, after being followed for two blocks, while walking her dog. These are just the incidences that I know of from the beginning of the summer, not including my own experiences while training over the past ten years.

Problem Statement:

The device that I would like to drastically improve and design is the brass knuckles, otherwise known as knuckles, knuckle busters, or knuckle dusters. Current knuckles are mostly a one-size-fits-all design. They are bulky, heavy, and are difficult to tote around while being active. My version would be geared towards females, athletes in particular, who spend considerable amounts of time outdoors training, running, hiking, walking their dogs, or just enjoying nature. These individuals are very active and generally prefer to experience the outdoors solo. They have the desire to feel safe and the confidence to be able to defend themselves from an attacker. My design would be more ergonomic in that it would accommodate smaller hands. It would be made sleeker, lighter, remain durable, and become an extension of the hand. This device will not follow the ideology of “shrink it and pink it” that most women specific products consist of today. The updated design would be easy to use and house features that would inflict damage on an attacker in order to maximize the chance for escape and survival.

Female athletes and outdoor enthusiasts need to feel safe while being outside and doing the activities they love. When it comes to venturing out alone, the outside world is a completely different place for females than for males. Males don’t have to plan their routes dependent upon the amount of harassment they may encounter. They do not feel the need to include a male friend to tag along just so they can feel safe and complete their 5 hours of training in the mountains. They do not need to worry about whether or not what they wear will invite unnecessary comments from random people along the way. Female athletes want to do their work, have a good time while doing it, and return home safe like everyone else.

Pugh/Decision Matrix:

Weights %	Evaluation Criteria	Self Defense Device for Female Athletes
Weights %	Evaluation Criteria	Strategy 1: Elite		Strategy 2: Active		Strategy 3: Recreational
		Rating:	Score:	Rating:	Score:	Rating:	Score:
20%	Light Weight Material	5	1	4	0.8	3	0.6
20%	High Strength	5	1	4	0.8	4	0.8
20%	Comfort	5	1	4	0.8	3	0.6
15%	Small Size	5	0.75	4	0.6	3	0.45
10%	Affordability	3	0.3	4	0.4	5	0.5
5%	Multifunctional	1	0.05	2	0.1	3	0.15
10%	Aesthetics	4	0.4	4	0.4	4	0.4
100%	Total:	4.5		3.9		3.5
	Rating Scale: 5 = Excellent 4 = Very Good 3 = Good 2 = Fair 1 = Poor

Justifications for Matrix:

The three key factors that are essential in the design of this device consist of light weight, high strength, and comfort. Without one, the device fails in overall effectiveness. Therefore, these three factors were weighted at 20% each of the overall weight of 100%. The idea of the device is to aid in creating force in a punch when defending oneself in a life or death situation. Therefore, the material selected must have a high strength-to-weight ratio in order to not only aid in creating force, but also withstand impact, while remaining comfortable to wear. Another characteristic in the design of this device is that it must become an extension of the hand, so the size is a key factor as well. Since the target market will be female athletes, the overall size of the device will be smaller, but extra care will be taken to create a range of sizes suitable for the ideal group of individuals who will be using it. Therefore, a weight of 15% was given to this criterion. Affordability was assigned a 10% weight. Affordability usually scores higher in other areas of consideration; however, it was decided that when it comes to life or death, affordability is not as essential. Stylishness is important to females. We care about the appearance of things, so aesthetics was assigned a value of 10% as well. The factor of multifunction was assigned the lowest value of 5% because the main focus of the device is to provide the function of protection, therefore any extra uses such as acting as a bottle opener or a keychain are not quite as important as the other criteria that were considered. Strategy 1 scored the highest in the decision matrix with the most important criteria scoring the highest values.

[F]unction [R]equirements	[D]esign [P]arameters	[A]nalysis	[R]esources	[R]isk	[C]ountermeasures
Lightweight yet strong	Incorporate titanium or aluminum alloy	Evaluate each material’s strength-to-weight ratio, Hardness tests, stress-strain diagrams, biocompatible	Manufacturing Systems Textbook, Machinery’s Handbook, Solids	Titanium too costly, manufacturing titanium too costly, other metals too heavy	Recyclable: find manufacturers that work with recycled titanium to reduce costs, Find larger manufacturers who may sell leftovers from larger projects at a lower cost, Survey what activities in particular this target market will be doing to determine if titanium is necessary
Allow for comfort	Contoured grip at inner edge, soften edges around the fingers for better fit	Size, shape of female hands, mechanics of the hand in general	Human anatomy, Actual people, Seeking opinions from female athletes, models of the hand	Too many differing shapes and sizes, inability to narrow down ideal sizes, too costly to accommodate all sizes, custom fits	Seek assistance from target market: take measurements from athletes and narrow down to three common sizes, do not offer custom fits or only offer custom fits as an add-on
Accommodate 4 fingers (full fist)	Remove bulk, soft smooth edges except at pointed tips	Angles, rounded edges and relationship to strength	Art and Design, Fashion and Style, Boxing, Martial Arts	Softening design may compromise its purpose, Statics, Solids, Physics	Must analyze force distributions and determine stresses device will experience, Research the mechanics of punching: what motion is most effective
Affordability	Maybe use a less expensive material that is still strong: Aluminum Alloy	Research the budget of this target market, how much they would spend	Demographics, Census, Outdoor Retailers & Sports Retailers	Retail cost may be too high, target market may not see importance of device	Find most cost-effective manufacturers, Locate most affordable materials and labor, smart marketing practices

Sketch 1:

Concept 2

[F]unction [R]equirements	[D]esign [P]arameters	[A]nalysis	[R]esources	[R]isk	[C]ountermeasures
Lightweight yet strong	Materials: can use titanium or can use heavier material (aluminum, other alloys)	Stress, strain, Creating maximum power, Evaluate each material’s strength-to-weight ratio, Hardness tests, stress-strain diagrams, biocompatible	Manufacturing Systems Textbook, Statics, Solids, Machinery’s Handbook, Physics	Costly if using titanium, Too heavy if not	Survey what activities in particular this target market will be doing to determine if titanium is necessary, Recyclable: find manufacturers that work with recycled titanium to reduce costs, Find larger manufacturers who may sell leftovers from larger projects at a lower cost
Allow for comfort	Contoured grip at inner edge, soften edges around the fingers for better fit	Size, shape of female hands, mechanics of the hand in general	Human anatomy, Actual people, Seeking opinions from female athletes, models of the hand	Too many differing shapes and sizes, inability to narrow down ideal sizes, too costly to accommodate all sizes, custom fits	Seek assistance from target market: take measurements from athletes and narrow down to three common sizes, do not offer custom fits or only offer custom fits as an add-on
Allow for small hands	Smaller diameter finger holes, decreasing width of device	Measure smaller hands, female hands, hands of target market	Measurements with scale, calipers, molds of ideal hand size, Retail sizing references	Too many sizes, too many different geometries	Choose most common sizes, survey groups of athletes to collect data, Categorize into 3 main sizing options
Effective damage at moment of impact	Add spikes to outer face, add larger spike at fist end, provide better distribution of force to the wearer’s fingers	Research motion of the arm when throwing a punch, forces involved in punching, what the hand absorbs when punching, how well does material work for this type of impact	Physics, Human Anatomy, Body Mechanics, Statics, Solids, Manufacturing System Textbook, Machinery’s Handbook	Device will be considered a weapon, may be illegal in some areas, could injure the wearer	Research laws pertaining to carrying concealed weapons in areas, Only provide device to those who have license to carry, Strategically place spikes in areas that will not cause injury to wearer in case of a fall
Allow for multifunction	Incorporate keyring hole, bottle opener edge	Determine how extra features will impact final design, will they impede?	Opinion from public, referencing outdoor equipment & accessories	Extra features add on weight and bulk, may take value away from main purpose of device	Stick to small features, keep design simple, focus on ultimate goal of device, eliminate multifunction all together

Sketch 2:

Concept 3

[F]unction [R]equirements	[D]esign [P]arameters	[A]nalysis	[R]esources	[R]isk	[C]ountermeasures
Lightweight yet strong	Use of titanium as material	High strength-to-weight ratio, biocompatible, corrosion resistant, Hardness tests, stress-strain diagrams, biocompatible, recyclable	Manufacturing Systems Textbook, Machinery’s Handbook	High cost of materials, High cost of manufacturing	Recyclable: find manufacturers that work with recycled titanium to reduce costs, Find larger manufacturers who may sell leftovers from larger projects at a lower cost, Survey what activities in particular this target market will be doing to determine if titanium is necessary
Allow for comfort	Incorporate contoured palm grip (interior edge), soften edges around the fingers for better fit	Size, shape of female hands, mechanics of the hand in general, biocompatible so will not cause allergic reactions	Human anatomy, Actual people, Seeking opinions from female athletes, models of the hand	Too many differing shapes and sizes, inability to narrow down ideal sizes, too costly to accommodate all sizes, custom fits	Seek assistance from target market: take measurements from athletes and narrow down to three common sizes, do not offer custom fits or only offer custom fits as an add-on
Minimalist design	2-finger device instead of all 4 fingers, remove bulk	Stress-strain analysis, minimalist design research, jewelry resources	Art & Design, jewelry design, current trends, Solids	Removing bulk may weaken device, will require increased machining, target market may not like minimalist design	Seek feedback from target market pertaining to preferred design styles, Find areas of device that need the most strength
Proper size range	Focus on smaller hand size but also design a range of sizes	Analyze common sizes of different categories of people, age categories, activity categories	Observation at races, outdoor events, sports events, consulting retail experts	Small sizes too small, large sizes too large…exclusion of wide range of sizes	Provide a few different sizes that would accommodate everyone, Offer custom fits
Aesthetically pleasing yet functional	Spikes along outer edge, Larger side spike at end, incorporate features of jewelry (stones, skulls, etc.)	Limitations of titanium and adding colors	Retail Industry, Manufacturing Systems Textbook, Current fashion & trends, jewelry design	Added features means more labor, more labor means higher cost of manufacturing	Locate low cost manufacturing, Utilize scraps from other manufacturers

Sketch 3:

concept sketch 3

Equations that May Apply:

Force:	Energy Transfer:	Impulse:
F= ma For a 130lb person, the arm & fist is about 5.25% of total weight: m = 3.096 kg (assuming): t = 0.1 s v = 10 m/s a = 100 m/s^2 F = (3.096)(100) F = 309.6 N	KE = (1/2)mv^2 Mass (fist & arm) = 2-4kg Velocity = 10-15m/s^2 KE = (1/2)(2)(10^2) KE = 100 J KE = (1/2)(4)(15^2) KE = 450 J KE = 100 - 450 J	J = Ft Force = 310 N Time = 0.1 s J = (310)(0.1) J = 31 Ns
Stress (fist):	Stress (device):	Momentum:
Stress = F/A Stress = 310/.04 Stress = 7750 Pa	For a pointed tip, surface area decreases significantly. Reduction in surface area will result in increase in Stress. Stress = 310/.01 Stress = 31000 Pa Stress = 310/.005 Stress = 62000 Pa	P = mv Mass = 4 kg Avg. velocity (fist) = 11 m/s P = 44 kg m/s

Activities Date and Time:

10/5/2018: 3:15pm – 5:30pm: Research physics behind punching & brass knuckles

10/6/2018: 1:00pm – 7:00pm: Decision Matrix, Multiple Solutions, Gantt Chart

10/7/2018: 10:50am – 12:30pm: Gantt Chart, Concept development, Sketches, Lessons Learned

4:30pm – 6:30pm: FRDPARRC Tables, Equations

10/8/2018: 2:00pm – 3:00pm: Equations, Sketches

10/9/2018: 10am – 12pm: Equations, Sketches

4:20pm – 6:00pm: Concept sketches

10/10/2018: 7:00pm – 9:30pm: Comments Advisees, Final Updates, Update Website

Comments to Advisees:

Lucas Shevlin:

Good problem statement
I like how your entire Gantt Chart can be seen in one shot
Colored sections make it easy to follow and understand your Decision Matrix
Great that you were able to incorporate sketches and solid models for each concept
Pros and Cons for each concept is a great idea
Maybe incorporate more equations
Add in your Advisee comments and you should be good to go (you’re probably working on it right now).

Bradley Darnell:

Waiting for Assignment to be added to webpage