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Contents 1 Executive Summary 2 Needs & Stakeholders 3 Product Use & Function 4 Bill of Materials 5 Design for X 5.1 Design for Manufacture (DFM) 5.2 Design for Assembly (DFA) 5.3 Design for Environment (DFE) 6 FMEA 7 Analysis 8 References

Executive Summary

(Waiting for other content)

Brandon

Needs & Stakeholders

Alpine skiing is a popular sport worldwide. The premise is nothing more than affixing stiff runners to one’s feet and proceeding down the side of a mountain to the equipment installed to transport the skier uphill for another round of downhill skiing. However, such a simple sport has ballooned into a multi-billion dollar industry. Every year, some 6.3 million Americans visit the 481 alpine skiing resorts operating in the United States<ref>National Ski Areas Association. "Industry Stats." <http://www.nsaa.org/nsaa/press>.</ref>. They spend, on average, 9 days on the slopes. Their ages span from pediatric to geriatric, averaging to 33. The ski mountains frequented by day are often surrounded by a resort village sized to accommodate the large amount of often wealthy tourists. As many once-booming coal towns became ghost towns once the coal supply was exhausted, these ski towns would face certain downsizing and restructuring were the ski industry to collapse<ref>"Mild Winter Affects the Economy." Vermont Business Magazine. May 2007. <http://findarticles.com/p/articles/mi_qa3675/is_200705/ai_n19430501/pg_5></ref>. These owners, proprietors, and employees are dependent on an industry of enjoyment.

Downhill skiing would not be possible without its namesake equipment, the ski. In turn, a ski is useless without a way to attach it to the human body. The ski boot fulfills this surprisingly complicated role. Skis generate forces and moments in all directions upon the foot, and the rider exerts forces upon the skis to turn, jump, and stop. Boots must strike a balance between weight, stiffness, comfort, and price. Quality ski boots sell for between $200 and $600 and must be fitted properly to give the skier control over the skis<ref>C.f. Alpine Ski Shop, a ski equipment retailer. <http://www.alpineskishop.com/skiboot.html>.</ref>. Ski boots are shaped largely like a normal boot, though have three major additional features. First, ski boots must largely immobilize the ankle. Pressure from the shin against the tall tongue of the boot is necessary for ski control, so a rigid boot is necessary to transmit that force. Second, these rigid boots use metal buckles to tighten their exoskeleton around the foot. Buckles provide a convenient method of tightening and loosening the boots as necessary, for wear and for removal. Third, ski boots must attach to the skis. In the early days of skiing, boots were clamped securely to skis with no means of emergency detachment<ref>SkiingHistory.org: "The First Release Bindings."<http://www.skiinghistory.org/releasebindings.html></ref>. After the problem of broken legs and ankles arose, emergency-detach ‘bindings’ were developed to allow a ski to break free of a (crashing) skier. Modern bindings (and thus, modern boots as well) follow a standardized interface design. A hard heel and toe of the boot are mandatory, as are slight protrusions from the heel and toe.

The heel and toe hardness, along with the ankle stiffness, make walking in ski boots a harrowing task (more on this below). Walking is a necessity: upon arriving at the ski slope, the typical skier will put on his ski boots, place his shoes in a locker - lest he carry them - and proceed – skis in hand – across an icy surface to the ski slope. Crowds and stairs are frequent obstacles. Ski boots commonly include treaded pads on the sole to improve traction on slippery surfaces. And, in an attempt to regain ankle mobility, a universal solution is to unbuckle the boots. As a tradeoff for ankle flexibility, the foot is exposed to cold air and snow; small children and novice skiers may be unable to re-buckle their own boots. And in the end, walking is still awkward.

[diagrams]

This walking problem is a nuisance 60 million skier-days per year. Manufacturers are tied to an industry-standard design which prevents modification of the boots themselves, and ski resorts are partially exempted from liability for personal injury<ref>"Survey of Ski Law in the United States" <http://www.skilaw.com/skilawsurvey.html></ref>. As such, the consumer (wearer) is the party most directly affected by the difficulty of walking. With 40% of the skiing population having a household income of over $100,000, these consumers have the economic means to purchase or rent additional beneficial equipment, such as inexpensive, convenient attachments to make walking easier.

Product Use & Function

Not surprisingly, an inexpensive attachment to facilitate walking does exist. The attachment replaces the flat walking surface of the ski boot with a curved surface which smoothes the stride. And, unlike the boot sole, it can be cushioned and can use materials selected to provide increased traction.

Major Functions

• Smooth the stride
• Traction
• Cushioning

[diagrams]

The device attaches to the standard binding tongues on the ski boot using a simple clip mechanism found on other ski products. It can be installed and removed quickly with the flip of a lever: the toe tongue of the boot is placed in the front orifice, the heel tongue is set in place, and a lever is tightened to secure the boot to the device. For the sake of convenience, it folds in half for easy stowage when not in use. It feels and appears rugged enough to support the repetitive stresses of the user’s weight, yet the design is reasonably lightweight, as carrying heavy gear while on the slopes is unpopular.

Major Characteristics

• Lightweight
• Simple
• Easy to install & remove
• Rugged

Bill of Materials

Jarrett

Part Number	Image	Name	Qty	Function	Material	Manuf. Process
1		Widget	.618	Be a widget	Widgetite	Sorcery
2

Design for X

A “Design for Manufacture and Assembly” (DFMA) analysis of a product evaluates the efficiency of the product design in terms of the ease and low cost of the manufacturing and assembly stages. The following discussion examines why certain components of the ski boot and its attachment were made in the specific manufacturing process. It also discusses the possibilities and feasibilities of improving the product design through either reducing the number of components (for reduced manufacturing costs) or redesigning of components (for easier and quicker; hence, more cost efficient assembly). In addition, a DFMA analysis complements a Failure Modes Effects Analysis (FMEA) as it seeks to improve the overall product design rather than just focusing on preventions of a failure.

Design for Manufacture (DFM)

The design for manufacture analysis discusses how individual components of the ski boot and its attachment were manufactured in order to optimize the ease and cost of manufacturing process. The analyses on the main components of the ski boot and the attachment are provided below.

Ski Boot The components of ski boot could be divided into five major categories – the plastic frame, the inner plastic sole, the inner boot, series of (four sets for each foot) locking mechanisms, and front and rear bottom covers. In the following analyses, the design features that optimize the efficiency of manufacturing process, found in the plastic frame, locking mechanisms, and bottom covers are summarized.

Plastic frame of the boot –

Locking mechanisms – Each boot has four locking mechanisms (sub-assemblies) that consist of a geared belt and a spring loaded hook that hold the two sides of the boot tight to provide better fit for users. For more user friendly design, one of the buckling mechanisms (the bottom buckling mechanism of high ankle component) needs to have a rotating hook. However, manufacturing rotating hook requires production of two parts (the outer frame that will secure the hook to the boot and an inner hook that locks on the channel). In order to reduce the cost of manufacturing, the ski boot uses two rotating hooks and two rigid hooks as opposed to using four rotating hooks. Rigid hook (which is a single component as opposed to a sub-assembly) allows lower cost of manufacturing; therefore, by replacing rotating hooks with rigid ones where the hooks do not need to rotate, the manufacturing cost goes down. What is even more interesting about the buckling mechanisms used in this particular ski boot is that as opposed to using three rigid hooks and one rotating hook (the boot only needs one hook that needs to rotate), it uses two of each. This decision was made in order to reduce the time of production. While manufacturing rigid hooks would cost less, having to manufacture three rigid hooks for every rotating hook manufactured would cause idle time for the machinery that manufactures rotating hooks. By using equal numbers of the two hooks, manufactures not only reduce the cost, but also achieve the minimum time of production achievable. For a product like a ski boot (whose market demand fluctuates from season to season), minimal time of production could be essential as that would allow the manufactures to meet volatile market demand without having to spend significant amount of inventory cost.

Front and Rear rubber covers of the ski boot – Although ski boot itself requires separate castings for manufacturing right boot and left boot, the rubber covers for both feet are identical (just like the attachments). Also, the pattern on the bottom of the covers (made to provide the user with more traction) suggest that the front and the rear halves of the covers were manufactured in one casting, then cut into two separate pieces. Thus, identical designs used for both feet; and use of one casting for manufacturing both front and rear halves lead to significant reduction in capital cost.

Attachment The ski boot attachment consists of three main sub-assemblies – front and rear soles, joint sub-assemblies (five joint pieces and a pair of pins), and spring loaded locking sub-assemblies.

Front and Rear soles of the attachment – The soles of the attachment provide the user with better traction and more comfort during walking process than a normal ski boots do. These components are made of rubber to allow reasonable amount of elastic deformation under operations to serve as cushions that absorb impact of landing while providing the user’s feet with sufficient support. Unlike the ski boot itself (or any other foot ware), the attachment soles’ design are identical for both feet. This leads to a significant reduction in manufacturing cost as the manufacturing process requires only one set of casting for rubber molding as opposed to two.

Spring loaded adjustable locking mechanism –

Design for Assembly (DFA)

A design for assembly analysis discusses how each component of the product was designed to minimize the time and cost of assembly. The DFA on the main components (and sub-assemblies) of the ski boot and the attachment are listed below. Ski Boot

Plastic frame of the boot – The bottom of the ski-boot (where the rubber covers are put on) has series of channels so that the covers can be secured even without using screws. This allows manufactures to easily place the covers on the right place without having to line up the parts.

More text to come

Design for Environment (DFE)

Taka

FMEA

Randy

Item & Function	Failure Mode	Effects of Failure	S	Causes of Failure	O	Design Controls	D	RPN	Recommended Actions	Responsibility & Deadline	Actions Taken	S	O	D	RPN
Perpetual Motion Driver	three	point	one	four	one	five	ten	just kidding	nine	two	six	five	three	five	eight
Cold Fusion Reactor	Talc	Gypsum	Calcite	Fluorite	Apatite	Feldspar	Quartz	Topaz	Corundum	Diamond	Social interaction	Walking in ski boots	?	?	?

Analysis

Taka, Jarrett, Randy, Brandon

References

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