Design Project 1: Shopping Cart - Pennsylvania State University

Introduction to Engineering DesignSection 204, Team 5Design Project 1: Shopping uJuly29,2015EDSGN100July29,2015

Executive SummaryThis paper discusses the design of a foldable, easy-to-use shopping cart that can hold 100 poundsand costs less than fifty dollars to produce- unless serving multiple purposes. Customer-needsassessment and the Internet helped determine suitability for groceries and durability mostimportant to shoppers. Cheap, strong materials were appealing and allowed profit.Team 5ii

Table of Contents1. Cover Page . .(Nadine)2. Abstract (Dominick) . ii3. Introduction3.1 Issue Summary (James). . . 14. Description of Design Task4.1 Problem Statement (James) . . . 14.2 Mission Statement (James) . 14.3 Design Specifications (James) . .15. Design Approach5.1 Project Management (Gantt Chart) (Nadine). . . .25.2 Customer Needs Assessment (Maria) . . 35.3 Concept Generation (Maria) . . . .3-65.4 Design Selection Matrices (Maria) . . .7-96. Final Design and Prototype6.1 Working Drawings (Maria, Kim, James) . . . 9-106.2 Prototype Scale and Images (Maria) . . . . 116.3 Design Features (Nadine) . . . . . . 11-126.4 Operation Instructions (Nadine and James) . . . . .127. Engineering Analysis7.1 Working Mechanism (Kim) . . . . . 12-137.2 Cost Analysis (Kim) . . . . . 148. Conclusion8.1 Summary (Maria) . . . . . 14-159.Acknowledgements (Nadine) .1510. References (Dominick) 16Team 5iii

3. Introduction3.1 Issue SummaryIn New York City and other highly populated areas it is often difficult to find a way totransport groceries due to the lack of vehicles and due to high-rise buildings. The Engineer’ssolution: to build an economical and storable cart. The team conducted a survey was to see whatindividuals cared most about in a collapsible shopping cart. The findings resulted in a shoppingcart that had a variety of storage areas, collapsible, and affordable.4. Description of Design Task4.1 Problem StatementConsumers need an easier way to transport groceries by foot after leaving the store. Thetransportation means must have a reasonable capacity and be collapsible for easy storage.4.2 Mission StatementIn order to provide a more convenient and reliable means to transport consumer goods byfoot at a minimal cost, a collapsible cart with set capacity was conceptually designed andevaluated.4.3 Design Specifications The shopping cart’s bottom frame 3ftx1.5ft with a 3/4” thickness Team 5The height was 3ft. The top frame for delicates is 1.5ftx0.75ft with a 3/4” thicknessThe top and bottom frame are collapsible to the main frame, which is 3ft tall.The shopping cart has two different compartments the top being for eggs, bread, andother delicate grocery items.The bottom could be used for any other groceries (water, soda, other bulky items) thefolding shopping cart material altogether came to a total of 32.57.The shopping cart has a weight capacity of 150 pounds.1

5. Design Approach5.1 Project Management (Gantt Chart)Table 1. Gantt ChartTeam 5 Cart Gantt ChartTaskEndStart DateCompletionDateEstablishing goalsand scheduling2-JulInformationGathering2-JulCost and RiskAssessment9-JulBrainstorming2-JulDesign MatrixSelection9-JulSet of WorkingDrawings(BluePrints)14-JulBuild and TestDesign Prototypes14-JulEvaluate DesignPrototypes14-JulDesignDocumentation andPresentationTeam 5Week Week Week123Week4Week5(7/1)(7/21)(7/28)(7/7) (7/14)100%100%100%100%100%100%100%100%100%21-Jul2

5.2 Customer Needs AssessmentA questionnaire was distributed to evaluate customer needs and preferences in basicconsiderations as well as specialty areas. Below are the summarized results of the distributedsurvey. Audience reported going to the grocery store between 1-8 times every 2 weeks.Most use a car to transport groceries greater than 5 miles, while a cart was reported as themethod of transport for a half-mile commute.A range of 2-15 grocery bags per trip was reported.Commute lengths ranged from 5-30 minutes.Terrain considerations were stairs, uphill sidewalks, crowds, slower-moving elderlypeople in area, and hot cars (consideration for cold foods).Most important factors to the audience were having separate compartments to keepcrushable/breakable foods safe, raw meat separate, cold foods preserved, comfort andspeed of use.Most consumers would not prefer to pay more than 20 for a cart.Average scores for qualities rated on a scale of 1-5 (5 is most important):Table 2. Average Design ScoresEase of use:4.8Durability:4.8Weight capacity:4.3Collapsibility:4.2Cost:4.0Weight of cart:4.0Safety:3.8Attractiveness:2.2These results were used to drive creative design features and to determine and factor importancefor the weighted design matrix. The initial six designs inspired by these criteria follow.5.3 Concept GenerationThe team members each developed 3-5 rough sketches to represent various cart concepts.After discussing each, the following six designs were chosen to continue for further evaluation.Team 53

DESIGN A: Premade BasketsAfter browsing online for costcontained materials, a simple designutilizing premade grocery basketsin a minimal metal frame wasconceived. With this design,groceries would be placed inbaskets that rested in a collapsibleframe. The baskets could beremoved for easy unloading ofgroceries. After, the frame wouldfold up and be placed in thestackable baskets for storage.Figure 1. Design ADESIGN B: Folding BriefcaseThis extremely compact design focusedon ease of use, collapsibility, andattractiveness. The flat, compacted cartcould be carried easily in the hand,looking as stylish as a standard briefcase.Flaps fold up from each side of the caseand are stuck together with Velcro toform a wagon-like cart with telescopingdragging handle for use. Straps are alsoused to hold the case together whenentirely folded. Caster wheels swivel inand out of grooves in the case for evenflatter storage.Figure 2. Design BTeam 54

DESIGN C: Zipper CollapsibleThis cart design focused oncollapsibility and easy itemremoval. It can be madeextremely compact because ofsimple cloth construction ontop of a rolling platform. Azipper runs from the base tothe top of the expanded cart bycircling around it severaltimes, allowing for eitherinternal divisions or foroptional sizes. The more thecloth is zipped, the larger thevolume of the higher bag. Themore the cloth is unzipped, thelarger the fabric strap forpulling and the easier theaccess to itemstowards thebottom of the cart no bendingand reaching into the cart). A handle is used to pull the rolling platform around.Figure 3. Design CDESIGN D: Nylon Strap FoldoutThis design makes use of verydurable yet economical materials and simpledesign. A metal frame forms two platformssuspended and spanned by strong nylonstraps. A small upper basket keeps breakablegroceries separate from large items on thebottom. Straps allow the frame to fold upinto a tall and flat storable form.Figure 4. Design DTeam 55

DESIGN E: Fishnet Basket with ScooterThis design incorporates afold-down scooter foot boardto make pushing easier andadd a second use. A fishnetbasket holds a large volume ofgoods without adding a lot ofweight, while nylon strapsacross the bottom supportheavier items. The basket foldsdown and the bottom platformand scooter boards fold up toyield a wider-than-others, butstill compact, folded cart. Ahandlebar serves both to guidethe scooter/cart and to carrythe folded item.Figure 5. Design EDESIGN F: Accordion Folding CartThis design works like the compressible water bottlesof a stiff plastic. It can be expanded by pulling up theplastic walls to be self-supporting, and a bit ofdownward effort on the top faces gives a compressedform. An inner shelf sits between the plastic ridges toseparate food items. Items can be loaded through theremovable top (bottom is accessed by removing shelf).The upper container rolls on a flat platform on casterwheels.Figure 6. Design FTeam 56

5.4 Design Selection MatricesAfter initial concept generation, the six concepts above were evaluated in a simple designmatrix using Design A as the standard.Table 3. Simple Design MatrixSimple Design Matrix - Project IEase of useSuitabilityforgroceriesCollapsibilityCost ofmaterialsWeightcapacitySafetyDurabilitySum Sum Sum 0Net TotalRankCONCLUSION: keep?Design A PremadeBasketsDesign B FoldingBriefcaseDesign C- 00Design DesignEFFishne AccorditonBasket 50251Yes-1-1043-56No-1-1142-35NoDesigns A and D were chosen to continue with potential for improvement, with DesignsB and C chosen to continue as ideas for modification/inclusion.Team 57

After modifications of the designs that were retained from the first design matrix, a seconddesign matrix was used to select the final concept. The categories of consideration were rankedbased on the average rating on a scale of 1-5 given by consumers to the area, converted to apercentage.Table 4. Weighted Design MatrixWeighted Design Matrix - Project IAttractivenessEase ofuseSuitabilityforgroceriesCollapsibilityCost ofmaterialsWeightcapacitySafetyDurabilityTOTAL 2RankingConclusion: keep?Standard PremadeBasketsWeight Scor edScore31.29Nylon StrapFoldout ModifiedSco Weightedre Score31.29ZipperCollapsibleModifiedScor 9120.394no3no1yes2noThe modified version of the original Nylon Strap Foldout cart was chosen to bedeveloped into a conceptual prototype.Team 58

6. Final Design and Prototype6.1 Detail DrawingsFigure 7: Detail 1Figure 8: Detail 8Team 59

Figure 9: Detail 7Figure 10: Detail 4Team 510

6.2 Prototype Scale and ImagesScale Used 1:4Figure 11: Prototype PhotosFigure 12: Cart Drawing with BOMScale Used 1:86.3DesignFeaturesOne of the main design features is the collapsibility of the cart and the fact that it takes upminimal space, as shown in the working mechanism and working drawing. The cart is also ableto withstand over 100lb of force, with a rating of 150lb. The cart also has multiple compartmentsTeam 511

that are available to store delicates on the top basket and more bulky items on the bottom. This ismore than just a traditional shopping cart, with added hooks to store more groceries. There is aspecific place for each different type of grocery. Coupled with its lightweight frame for easytravel, this cart is simple to use but practical at its core.6.4 Operation InstructionsCollapsing the cart1.2.3.4.Unhook top basket from mainframe.Lift up the back of the top basket until it’s parallel with the handle bar.Lift up the bottom unit until it is parallel with the handle and top basket part.It is now in its fully collapsed stage and is ready for storage.Setting up the cart for use1. Pull the bottom basket down until it is fully secured on the ground.2. Push the top basket down until it is aligned with the bottom basket.3. Hook the top basket to the mainframe to fully secure it by resting the hook on the mainbar.4. Cart is fully assembled and ready for use.* Weight capacity is 50lb on the top basket and 100lb on the bottom basket.7. Engineering Analysis7.1 Working MechanismIn order to make a strong and collapsible storage space, a hooked frame with a triangleprofile was used. Swivel connection enables the frame to fold to a smaller form. By using hookattachment, the base leg of the right triangle detaches from the vertical frame and folds inside it.To make sure the frames fold parallel to each other, each vertical pole set (blue, orange, green) ispositioned at a different width. A hook device locks the swivel frames in place for use.Team 512