Product Design & Development

Student Name Tony PonsonbyStudent Number 02968984Unit Code 64ET7004 1112 9Unit Name Product Design And DevelopmentAssignment Code1CWK40

Redesign of a Reebok Edge Series Cross Trainer Foot Plate Linkage

Users ScenarioBackground• The users of the cross trainer are male & female,

the design does not favour either sex • The machines rated capacity dictate there would

be more female users• The pricing of the machine will appeal to the

more serious home gym equipment users or those with a higher expendable income

• The equipment is ideal for individuals with busy lifestyles; either those who work long hours or are at home looking after children.

• The Reebok Edge cross trainer delivers high quality equipment to the fitness enthusiast for convenient home exercise

• Cross trainers are used for low impact exercise as compared to other cardiovascular exercises equipment such as treadmills this makes the equipment suitable for rehabilitative physiotherapy or exercise for persons with joint problems.

The Modern MumKate is a busy 35 year old working mum who lives in Manchester, being typical of western culture she balances family life on top of working part-time in an office. After work Kate collects the kids and makes tea for the family, she then uses exercise a way to unwind from a long day. Kate takes pride in her appearance and wants to look good but as result of her hectic lifestyle, exercise isn't a routine, it has to conveniently fit around her other commitments so she uses home gym equipment to facilitate this.

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CUTE Values – Reebok Edge Cross Trainer Linkage

Communication

• Has a unbiased design not driven to either sex

• The cross trainer looks modern and has a desirable appeal, however the linkage looks unduly complicated & unrefined

• The styling of the linkage covers makes the machine look more durable than the machine actually is

• Doesn’t look or feel as sturdy as a cross trainer typically found within a gym

• The branding is synonymous with fitness, however there are few logos or images of on the machine

• Has a unbiased design not driven to either sex

• The linkage design should stand out from other cross-trainer linkage designs, taking modern look to a new level and increasing desirability

• The styling should make the machine look more durable to compete with higher specification machines

• The shape of the linkage will be sleek and organic in appearance as if grown, sharp edges will be minimised

• The synonymous branding will form part to the grip on the tread-plate

Existing Redesigned

CUTE Values – Reebok Edge Cross Trainer Linkage

User• Designed for the home use exercise market, this

item is not does not have the same build quality and rigidity of cross trainers used at gyms

• 120kg weight capacity probably suggests more female users

• Convenient way to exercise• The working envelope of the machine is

1300mm x 580mm• The grip in the tread plate is rubber • There are 56 parts in both foot plate linkages for

the home user to assemble, this increases the complexity of assembly. In majority of cases I believe that assembly will be carried by a person of a non-technical background

• Time consuming home assembly (about 40 minutes to assemble the cross trainer)

• The cross trainer has a manufacturer's 2 year guarantee

• Designed for the home use exercise market, the new design will improve on build quality and appear more desirable than traditional linkages

• 120kg weight capacity probably suggests more female users

• Convenient way to exercise• Same working envelope• The tread plate that the user stands on is fixed and

will be of a suitable size to accommodate all• The Reebok branding will form part of the tread plate

grip in addition to surface roughness and ribs • The new design will reduce the number of

components and complexity, this will be beneficial to;– Reduce the assembly time– Ease the assembly especially those from a non-

technical background – Reduce the number of assembly tools

• The cross trainer has a manufacturer's 2 year guarantee

Existing Redesigned

CUTE Values – Reebok Edge Cross Trainer Linkage

Technical• The linkage is part of a Reebok edge crosstrainer• Retailing in Argos for £299.95 (22/10/11)• ABS moulded black covers on foot rest and end pin joints

• The main linkage is a steel powder coated tubular fabrication • Maximum user weight 120kg • The linkages account for 6kg of the 44kg full package weight• All mouldings and fabrications are unique to Reebok• The footplate linkage s are handed• The crank end connection uses an NSK 2203-2RS double row self-

aligning ball bearing. This bearing will allow misalignment that could stem from manufacturing inaccuracies

• The user has to assemble 56 individual components to construct the right and left linkages, of which there are 19 unique components.

• The linkage fabrication comprise of 6 fabricated and 2 assembled components

• Manufacturing processes required are; – Tube cutting by shearing– Tube hole punching– Sheet metal cutting – probably laser cutting– Sheet metal folding– Bar parting-off on a lathe– Welding – probably using some jigs or fixtures– Powder coating – Vacuum moulding of ABS components– Vacuum moulding of rubber components– Bonding of the rubber foot grip to the ABS foot plate– Manual assembly

• The linkage is part of a Reebok edge crosstrainer• The new linkage will be a 1 or 2 piece moulding • Maximum user weight 120kg • The new linkage mass will be around 3kg per pair • All mouldings will be unique to Reebok• The footplate linkage is interchangeable to either

side• The crank end connection uses an NSK 2203-2RS

double row self-aligning ball bearing• The redesign will reduce the number home

assembled components to 6 per side• The redesign will reduce the number factory

assembled components to 4 - 11 per side• Manufacturing processes required are;

– Vacuum moulding – Manual assembly

• No patents or design rights shall be infringed

Existing Redesigned

CUTE Values – Reebok Edge Cross Trainer Linkage

Environmental Existing• The steel, ABS and rubber

components can be recycled, however recycling by the home user is probably unlikely due to the need to strip down the components and find a recycler for the ABS and rubber as these are less widely available

• The rubber inlay within the foot plate is also quite difficult to separate from the ABS foot plate

Redesigned• All materials used shall be readily

recyclable and contain information within the packing to facilitate this

• Where distantly is required for recycling, this will be made as easy as possible

• Material variants shall be reduced to a minimum

Existing Linkage Design

Existing Linkage Design

Existing Linkage Design

Existing Linkage Design

Existing Linkage Design

Project Sketchbook

Design BriefAims• Reduce the weight of the linkage assembly • Reduce the weight of the overall package• Reduce the number of parts for the home user to assemble and

tools required• Reduce the number of parts for the manufacturer to assemble• Reduce the number of manufacturing processes required to produce

a linkage • Improve product branding• Retro fit onto machines of existing design • Make the linkage be interchangeable to fit either side• The tread plate will be fixed• To register the design of the components designedConstraints• The new linkage design should replace the existing linkage and

connect to the existing design of the crank and handle connections • The colour of the new design should be black to match existing

components• The linkage should be capable of being loaded by a user weighing up

to 120kg • The footplate should have suitable grip• The linkage should exceed a minimum of 2 years service• The primary component/s within the new design should be designed

to suit manufacturing by injection moulding

Goals• To make home user assembly easier and faster• Reduce cost of the existing linkage• Reduce the weight of the cross trainer package to make

transportation and handling easierTimescale 2nd November 2011 – Initial Project Deadline • User scenarios• Lifestyle boards• C U T E values• Detailed design brief• Project sketchbook• Develop 2 alternative proposals• Propose materials• Initial CAD architecture14th December 2011 – Final Project Deadline• Develop the final design• Define the materials used within the final design• Produce a detailed 3D solid model of the linkage using

SolidEdge • Rapid prototype linkage• Final project presentation & poster

Proposed Design 1

Proposed Design 1

Proposed Design 2

Proposed Materials

Existing Linkage Materials• Fabricated tubular steel linkage

body• Plastic injection moulded ABS

covers and tread plate• Bonded Rubber grip strip inside

the tread plate

Possible New Linkage Materials• PC – polycarbonate• ABS - acrylonitrile butadiene

styrene• HDPE - high density polyethylene• PEEK – polyetheretherketone• Acetal – POM