Mech 202 Project 1

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Cover Sheet

Group Number 21

Group Members Email Addresses

Heidi Potton [email protected]

Trent McNamara [email protected]

Krystal Tamayo [email protected]

Bryce Wilson [email protected]

Section Pages where found

a. Cover sheet 2

b. Photo and superimposed CREO model 3

c. Project plan 4‐9

d. Exploded assembly drawing(s) 10‐11

e. Bill of materials 12‐13

f. Detailed description of how device works 14‐24

g. 2D engineering drawings 25‐44

h. Description of research 45‐61

i. Sketch, description, and analysis of improvement 62‐82

j. Teamwork analysis 83‐92

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Photo and Superimposed CREO Model

Figure 1: Superimposed CREO Model

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Project Plan

The figure above is our first Gantt chart created on January 27th, 2015. This was created upon early understanding of the requirements of

a Gantt chart and the necessary factors that contribute to a successful team projects. One of the most notable issues with this chart that was

fixed in later iterations was the distribution of tasks. This chart demonstrated that we had originally marked many tasks as being under shared

responsibility of the entire group. We later realized that this is generally an inefficient means to complete a project, however, and distributed the

tasks between individuals instead. Time estimates to complete tasks were generally increased in later charts, and adjustments were made to

dependencies in order to better define the critical path of this project.

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Exploded View

Front view:

Figure 2: Exploded view, front with annotations

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Top‐Rear view:

Figure 3: Exploded view, top without annotations

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Bill of Materials

Item # Name of Item Description Manufacturing Process

Quantity Weight Weight units

1 PACKAGING SUBASSEMBLY 1.1 Box Materials: cardboard

Size: Corrugating 1 85 grams

1.2 Support Braces Materials: cardboard Size:

Corrugating 2 7 grams

1.3 Coverings Materials: plastic Size:

Blown film extrusion

1 1 grams

1.4 Instruction Manual Materials: paper Size:

Chemical/mechanical process

1 13 grams

1.5 Power Cord Materials: plastic Size: 30.5x40x30.5mm

Injection mold 1 95 grams

2 CASING UNIT SUBASSEMBLY grams

2.1 Shell Casing Right Materials: plastic Size:220x165 mm


2.2 Shell Casing Left Materials: plastic Size: 220x165 mm


2.3 Front Casing Materials: plastic Size: 220x100 mm


2.4 Philips pan head screw Materials: steel Size: #6‐32 x ¼ in

Thread rolling 2 0.3 grams

2.5 Power switch cover Materials: plastic Size: 53x11x26 mm


2.6 Crevice tool Materials: plastic Size: 121.4x31.5x13.8 mm


2.7 Brackets for crevice tool

Materials: plastic Size: 10.6x8.4x10.4 mm


2.8 Valve Materials: rubber Size: 36x18.7x1.24 mm

Compression mold

1 3 grams

2.9 Filter button Materials: plastic Size: ɸ 48.38 mm


2.10 Spring Materials: metal Size: ɸ 62.1

Auto coiler 1 1 grams

2.11 Glue dots Materials: epoxy Size: 2mm

catalytic homopolymerisa‐tion

5 0.01 grams

2.12 Philips pan head screw Materials: steel Size: #6‐32 x 1/2 in

Thread rolling 4 0.3 grams

3 FILTER SUBASSEMBLY 15 grams

3.1 Filter Cuff Materials: plastic Size: ɸ 48.38mm


3.2 Filter Netting Materials: cloth Size: ɸ 62.1 mm

Woven 1 2 grams

4 CIRCUIT BOARD SUMBASSEMBLY grams

4.1 Power switch (black)

Materials: Plastic Size: 17.93x2.63x12.2 mm


4.2 Power switch casing (silver)

Materials: Steel Size: 22.3x6.27x13.94 mm

Press forming 1 2 grams

4.3 Circuit board Materials: Multiple Size: 57x24 mm

PCB process 1 5 grams

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4.4 White wire Materials: copper, plastic Size: ɸ 2mm

Extruding process 1 0.5 grams

4.5 Black wire Materials: copper, plastic Size: ɸ 2mm


4.6 Orange wire Materials: copper, plastic Size: ɸ 2mm


4.7 Red wire Materials: Size: ɸ 2mm


5 BATTERY SUBASSEMBLY grams

5.1 Battery/Motor housing Materials: plastic Size: ɸ 78 mm


5.1 Red Wire Materials: copper, plastic Size: ɸ 2mm


5.2 Black Wire Materials: copper, plastic Size: ɸ 2mm


5.3 Fuse Materials: plastic Size: ɸ 2mm

Internal construction varies

1 1 grams

5.5 Battery Cells Materials: Nickel plated copper Size: ɸ 2mm

Multiple processes

6 37 grams

5.6 Pads Materials: foam Size: ɸ 2mm

Polymerization 6 0.25 grams

5.7 Wire attachments Materials: metal Size: 5x6mm

Press forming 2 0.01 grams

5.8 Charging Port Materials: plastic Size: ɸ 10.4x8.85 mm

Injection mold 1 1.5 grams

6 FAN SUBASSEMBLY grams

6.1 Fan Materials: plastic Size: ɸ 67.5 mm


7 MOTOR SUBASSEMBLY grams

7.1 Motor housing and all interior components

Materials: multiple Size: ɸ 36mm

Multiple processes

1 122 grams

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Description of How it Works Power switch

By sliding the power switch cover towards the front casing, the power switch slides along with it. The power switch is composed of a metal strip on its bottom surface which then connects to two out of three metal contact plates (labeled A, B and C on the drawing below) of the circuit board. When the strip of metal on the power switch connects to contact plates B and C, it creates an open circuit and the vacuum cleaner is turned off and is able to charge. When the strip of metal on the power switch connects to contact plates A and B, it closes the circuit and a signal is received allowing current to flow through the motor. However, connecting A and B together also disables the charging port which is why the user is unable to vacuum while charging.

A

B

C

Figure 4: Circuit board and switch terminals

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Power and Drive

Once the power switch is actuated, 7.2 Volts and its corresponding DC current are sent

through the electromagnet inside the motor producing a magnetic field. Once the magnetic

field is produced, the flow of current though the armature (also found in the motor) interacts

with the magnetic‐field‐producing motion which drives the motor. The motor makes a shaft

spin which rotates the fan attached to it. The fan has angled blades; when the blades turn,

they force air into the vacuum cleaner. This occurs because the ambient pressure increases in

front of the fan and pressure decreases behind the fan. Since the ambient air pressure is

higher than the pressure inside the vacuum, the ambient air pushes itself into the vacuum

creating suction.

1) Batteries provide 7.2 Volts and its corresponding DC current to the motor.

2) The motor is powered which in turn makes a shaft spin and that rotates the fan attached to it.

Figure 5: Fan with drive system

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Air Flow‐ front casing

Once the fan creates suction, the valve opens and allows air carrying dust and debris

to be pulled into the nozzle. These particles are then stored in the front casing. The function

of the valve is also to prevent any backflow of air through the intake.

Once the fan creates suction, the

valve opens allowing air to flow

through the intake.

Figure 6: Airflow I

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Air Flow‐ rear shell casing

The filter allows air to travel through the system and exit through the side air vents

found in the shell casing right and shell casing left. However, the filter also prevents dust and

debris from diffusing back into the room.

1) The filter allows air to travel

through the system.

2) Air flowing through the

system exits through the side

air vents found in the shell

casing right and shell casing

Figure 7: Airflow II

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Crevice Tool

Since the speed of the fan is constant, the amount of air going into the vacuum cleaner

is also constant. If the intake port size is decreased (by using the crevice tool) then in order to

have the same amount of air particles flow into the vacuum, the air particles must travel at a

faster speed.

When the crevice tool is used, the

vacuum cleaner is able to pick up

debris faster from hard to reach

areas.

Figure 8: Airflow with crevice tool

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Battery‐ charging

If either a short circuit, excessive load or a flaw in the design were to cause the electric

current to be much larger than the current intended for the device, then the wire inside the

fuse will melt and stop any flow of current. The fuse prevents the overcurrent to possibly

cause a fire or damage the equipment. The fuse works when the circuit is closed (as explained

on page 12) and the vacuum is charging as well as when the circuit is closed and the motor is

powered by the batteries. In the following two diagrams both of these cases are explained.

While vacuum is charging:

1. When the circuit is opened, the charging port is then connected to the circuit board

and the batteries can now be charged.

2. Current flows from an electrical outlet into the charging port. This current then travels

through the fuse. If the current is much larger than the current intended for the

device, then the wire inside the fuse will melt and stop any flow of current. After this

the batteries cannot be charged anymore.

3. If the current flowing through the fuse is in the appropriate range for the device then

current will continue to flow and go through the circuit.

4. The electrical current now goes to the batteries and this is how they are recharged.

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2 3 4

Figure 9: Charging

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Battery‐ discharging

When batteries power the motor:

1. When the circuit is closed, the charging port is disabled and current is now allowed to

flow to the batteries.

2. The electrical current from the batteries now flows through the fuse. If the current is

much larger than the current intended for the device, then the wire inside the fuse will

melt and stop any flow of current. This will turn off the vacuum cleaner.

3. If the current flowing through the fuse is in the appropriate range for the device then

current will continue to flow and go through the circuit.

4. The electrical current continues to flow and powers the motor.

Information of how the vacuum works was gathered through various sources:

http://electronics.howstuffworks.com/motor2.htm

http://en.wikipedia.org/wiki/Fuse_%28electrical%29

http://home.howstuffworks.com/vacuum‐cleaner.htm

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Figure 10: Vacuum Operation

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Detailed Description of How the Device Works

Group 21 Project 1 Date: January 31, 2015.

Product Decomposed: Dirt Devil Easy Lite Cordless Bag‐less Handheld Vacuum , BD10250

Description: This product is a cordless, handheld vacuum cleaner. How it Works: Grab the handle part. Slide the power button towards the front casing. Vacuum desired particles. Once finished, slide the power button towards the handle part to turn off the vacuum.

Parts of this model:

Part # (Form BOM)

Part Name Function Directly Interfacing Parts

Image

2.2 Shell Casing Left

Holds and supports internal parts. Comprises half of the posterior housing and handle part. It also contains a side air vent.

Shell Casing Right, Fan, Motor, Batteries, Circuit Board, Power Switch Cover, wires, Fuse, Front Casing.

2.1 Shell Casing Right

Protects devise internals and completes the posterior housing of the devise. It also contains a side air vent.

Shell Casing Left.

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2.3 Front Casing Serves as a debris collecting department.

Filter, Crevice Tool, Brackets for Crevice, Valve, Shell Casing Left, Shell Casing Right.

2.6 Crevice Tool Provides an extension to the vacuum cleaner with a narrower opening. Helps clean hard to reach places such as corners.

Front Casing and Brackets for Crevice.

3.1, 3.2 Filter Collects dust and other small particles that enter the front casing, and prevents them from entering the motor or other electrical components of the vacuum.

Front Casing

2.8 Valve Allows dust and other particles to enter the front casing but it also prevents any backflow.

Front Casing

2.7 Brackets for Crevice Amount: 2

Maintains the crevice tool attached and enables it to rotate.

Front Casing and Crevice Tool.

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6.1

Fan The fan contains angled blades that generate air flow, forcing the air from outside the vacuum cleaner into the front cover.

Motor.

7.1 Motor An electric motor consists of an electromagnet and an armature (large coil of wire). The flow of current through the electromagnet produces a magnetic field and the flow of current though the armature interacts with the magnetic field producing motion. This motion is seen by the rotating shaft which makes the fan blades turn.

Fan, Batteries, Circuit Board.

5.5 Battery Cell Amount: 6

Converts stored chemical energy into electrical energy which then powers the motor.

Battery/Motor Housing, Fuse and Motor.

5.1 Battery/Motor Housing

Protects and keeps the batteries and the motor together.

Batteries, Motor, Shell Casing Right and Shell Casing Left.

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2.5 Power Switch Cover

Protects the power switch. By sliding the power switch cover towards the front casing, the power switch slides along with it.

Shell Casing Left, Shell Casing Right and Power Switch.

4.1, 4.3 Circuit Board, Power Switch

When the power switch is set to the “on” position, the circuit board receives a signal and transmits current through the motor.

Shell Casing Left, Power Switch, Power Switch Casing, Fuse, Batteries, Motor, and Charging Port.

5.3 Fuse A device that acts as a low resistance resistor. It is made up of a metal wire that melts when too much current flows through it. This protects the circuit by interrupting excessive currents from causing further damage.

Circuit Board, Shell Casing Left and Batteries.

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EngineeringDrawings–AllMeasurementsinmillimeters

Figure 11: Shell Casing Left

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Figure 12: Shell Casing Right

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Figure 13: Front Casing

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Figure 14: Battery/Motor Housing

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Figure 15: Battery Cell

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Figure 16: Circuit Board

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Figure 17: Crevice Tool

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Figure 18: Left Crevice Tool Bracket

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Figure 19: Right Crevice Tool

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Figure 20: Filter

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Figure 21: Filter Button

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Figure 22: Fuse

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Figure 23: Power Switch

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Figure 24: Power Switch Casing

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Figure 25: Power Switch Cover

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Figure 26: Fan

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Figure 27: Motor

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Figure 28: Valve

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Figure 29: Charging Port

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Figure 30: Charger

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Research

Comparing the competitors

1 Dirt Devil® Easy Lite Cordless Bagless Handheld Vacuum

Model: BD10250

5 Dewalt ½‐gal. Cordless 18‐Volt Wet/Dry Vacuum Model: DC515K

2 Black & Decker Dustbuster Bagless Cordless Hand Vac ‐ White/Blue Model: BDH7200CHV

6 Hand‐holdable vacuum cleaner Patent # US 8595895 B2

3 Eureka RapidClean Pet Cordless Handheld Vacuum, 80A ASIN: B009LXQBHI

7 Handheld vacuum cleaner Patent # US 8069529 B2

4 Black & Decker 14.4V Cordless Hand Vac Model: CHV1410

8 ELECTROLUX Hand held vacuum cleaner Patent # US 8225456 B2

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1) Dirt Devil® Easy Lite Cordless Bag‐less Handheld Vacuum http://www.target.com/p/dirt‐devil‐easy‐lite‐cordless‐bagless‐handheld‐vacuum‐bd10250/‐/A‐10296714

Model: BD10250 $16.49

Product Features

On/Off Switch

Rechargeable Batter

Portable

Cordless

Built‐in Crevice Tool

Lightweight

Product Description The Dirt Devil Easy Lite Cordless Bagless Handheld Vacuum is one of those lightweight and compact small appliances that you'll end up loving instantly. These hand‐held vacumms are made for easily cleaning up everyday messes making floorcare a breeze. Everyone needs a little help in this area and this item makes it quick and easy. With 7.2 volts, it gives you more power in a small package. It even includes a quick‐flip crevice tool to clean small spaces fast. This small vacumm features cordless convenience, a rechargable battery and is made for cleaning multiple surfaces. This is a cleaning tool that everyone needs. Battery is included

Details Recommended Cleaning Surface Type: Multi‐surface

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Vacuum Attachments: Crevice Tool

Power Source: Battery‐powered

Cleaning Path Width: 1.500

Capacity Total Volume: 4.000

Product Width: 4.500

Product Weight: 1.850

Product Height: 4.500

Charge Time 24 Hours

Customer Reviews Poor...For no good reason this thing stopped charging. Light on top burned out.

not so good I brought this thing two months ago and it does nothing! its a waste of money and my time trying to clean with it, only to turn around and do everything by hand.

Battery life very poor I bought this product last December and I'm starting to have issues with it now (Sept). I use it every morning for less than a minute. That is all the battery will handle. It is plugged in at all other times. The light on the charger rarely goes on. I have to try several outlets before it starts charging. Still, it cleans for only 1 min. After a 24 hr charge. Don't recommend this product.

WILL NOT HOLD CHARGE Purchased model (EASYLITE 7.2V) in March of 2014. It worked great. Now when take it off the charger and use it , it runs for about 30 seconds and quits. Have done as the manual says and let it run down completely and then let it charge for 2 days before trying to use it again, all with the same results. Not very pleased with this unit at all.

Choose another brand This is 2 months old. After complete discharges and recharges and keeping the cup spotless, it runs for 1 minute at best. Wish I had read the reviews before wasting my money.

Same Story As others have said, the battery does not hold a charge AT ALL. I've tried charging it for days, but it will only work for one minute, at most. It's disappointing, because I loved it the first few months of use.

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2) Black & Decker ‐ Dustbuster Bagless Cordless Hand Vacuum http://www.bestbuy.com/site/black‐decker‐dustbuster‐bagless‐cordless‐hand‐vac‐white‐blue/1902417.p?id=1219066879510&skuId=1902417&ref=06&loc=01&ci_src=14110944&ci_sku=1902417&extensionType=pla:g&s_kwcid=PTC!pla!!!79816477719!g!!46592478999&kpid=1902417&k_clickid=6039ae11‐9176‐4874‐bed3‐076489d84c7b&kpid=1902417&lsft=ref:212,loc:1&ksid=6039ae11‐9176‐4874‐bed3‐076489d84c7b&ksprof_id=13&ksaffcode=1100&ksdevice=c

Model: BDH7200CHV $17.99

Product Features Lightweight, handheld design Makes the vacuum easy to maneuver during use.

2‐stage filtration system Utilizes a prefilter and filter to help ensure strong suction.

7.2V of power To efficiently clean carpets and bare floors.

Push button bowl removal Allows easy emptying with the touch of a single button.

1‐9/10" cleaning‐path width Ensures thorough cleaning with every pass.

Washable bowl and filter Facilitate maintenance to enable thorough, hygienic cleaning.

Charging stand/wall mount For simple charging and storage.

ENERGY STAR certified This product contains an ENERGY STAR certified battery charger for a high standard of energy efficiency.

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Product Description This Black & Decker Dustbuster BDH7200CHV hand vac features 7.2V of power and a 2‐stage filtration system to ensure plenty of suction to clean a variety of surfaces. The dust bowl can be removed at the touch of a button for simple emptying.

Details Warranty Terms ‐ Parts 2 years limited

Warranty Terms ‐ Labor 2 years limited

Height 6 inches

Width 4.5 inches

Depth 16.5 inches

Weight 1.8 pounds

Color Category Multi

Corded/Cordless Cordless

Pet No

Bagless Yes

Cleaning Path Width 1.9 inches

Compatible Floor Type All floors

Multi Surface Yes

Edge Cleaning Yes

Pet Hair Vacuum No

Filter Type 2‐stage

Vacuum Type Handheld vacuums

Voltage 7.2 volts

Customer Reviews

Good suction I had a dirt devil and it did not have the power that this product has. I am very happy with this produce

Does exactly what it's expected to do At this price point, it's a fine little machine. I've used it for a solid two months, zero problems, strong suction, good battery life. Ease of access with it hanging on the wall in the kitchen. Prevents us from having to plug in the dyson every time we need to spot vacuum. If you have 25$ to spare, do yourself a favor and pick this up.

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Great piece of equipment but one problem This vac is quite handy. It has great suction and battery life. The one problem is when using on a slick surface you have to be very careful of the return vent as it blows air forcibly which can push debris further behind the device. Otherwise, 5 stars.

Perfect small appliance this is a great product it has great suction I had a Dirt Devil and this was superior plus the best thing is you can rinse out the filter in lieu of buying new ones great purchase

I love my handheld vac I love my handheld vac. It's everything I'd wanted. Always ready to be used, thanks to the very convenient charging station.

Excellent suction Awesome little handheld vacuum! I was surprised at how well it works. I use it everywhere: my car and my house. It has excellent suction, so I would really recommend this one for small jobs.

Toy This product is only for very small jobs that take less than 10 minutes. I charged this thing the whole night and it worked only for less than 15 minutes. Only for minor jobs.

Doesn't work for small dirt. I bought thinking I can use for car and house hold. But unfortunately the suction isn't enough to pull the dirt.

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3) Eureka Rapid Clean Pet Cordless Handheld Vacuum, 80A

http://www.eureka.com/en‐US/Vacuums/Lightweights/RapidClean‐Pet/Lightweights‐RapidCleanPet‐80A.aspx

Model: B009LXQBHI $56.78

Product Features

Tough Enough for Pet Owners Features tools made for removing pet hair

Powered Pet Brush A removable powered pet brush removes embedded pet hair from carpets and upholstery

Cordless Convenience Tackle messes quickly and easily with the cordless design

Charging Stand & On‐Board Tools Charging stand conveniently stores the hand vacuum, crevice tool and dusting brush

Easy Empty Dust Cup Empty dust cup quickly and easily without the mess

14.4 Volt Battery Clean larger areas on a single charge

Details Power 14.4V NiMH ‐ not replaceable

Cleaning Path Width 3 in.

Weight 3.8 lbs.

Shipping Weight 5 lbs.

Cleaner Dimensions 9”W x 7”L x 19”H

Available for purchase in Canada Yes

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Tools/Accessories Crevice tool, dusting brush, charging stand

Product Description The RapidClean™ Pet cordless handheld vacuum packs 14.4 volts of power into a lightweight vacuum designed with pet owners in mind. With the powered Pet Brush, RapidClean™ Pet is tough enough for pet owners with a powered pet brush that removes pet hair from carpet and upholstery! Plastic teeth loosen it, a rubber strip grabs it and bristles remove it. And with no cord to detangle or unwind, the RapidClean™ Pet cordless handheld vacuum tackles messes quickly and easily. A 14.4 volt battery allows you to clean large areas on a single charge. A charging stand conveniently stores the handheld vacuum, crevice tool and dusting brush while not in use. Customer Reviews

I found that something was broken inside and it makes a terrible noise... When this item came to me, I fully charged it and it charged OK. When I turned it on, it had no suction at all. Read more

Vacuum died after 4 months of use! This vacuum cleaner died 2 weeks ago after only 4 months of use. I called Eureka's customer service center and they promised me that they would send me a replacement.

While not as performant as the shark cordless, While not as performant as the shark cordless, it works well and the battery has already lasted longer than the shark's other vacuum.

Handheld vacuum Does not have much power, does not hold a charge very long and takes quite a while to recharge. I am very disappointed in this vacuum.

Worked literally once We charged it per the instructions (longer than the minimum required for first use) used it once and were satisfied with the power, features (powered brush head) and the battery was terrible.

No suction, doesn’t work After charging for three days, machine will not pick up anything.Very disappointed; shocked at the low quality and failure to operate.

Battery life is 2 minutes. Useless I saw some reviews and I should have listened…don’t waste your money Its useless...I was Ripped Off don’t do it. Worthless waste of my hard earned moneys.

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4) Black & Decker 14.4V Cordless Hand Vacuum http://www.blackanddecker.com/power‐tools/CHV1410.aspx

Model: CHV1410

$33.99

Product Features

On‐board brush and crevice tool

Rotating, slim nozzle

Removable, washable dirt bowl and filters for easy, hygienic clean‐ups

Wide‐mouth design

50 percent more reach than conventional Dustbusters

Translucent, bagless dirt bowl

Three versatile ways to store

Product Description The Black & Decker Cordless Hand Vac, CHV1410 is designed to help you clean up a variety of messes quickly and easily. Using the latest in Dustbuster and vacuum technology, it has a compact and lightweight design that allows it to reach into tight and difficult spaces. The Black & Decker hand vac has a translucent dirt bowl that can be easily removed and washed. Its cyclonic suction power is 50 percent stronger than comparable models. Its Energy Star‐approved charging system includes a charging light indicator for extra convenience. This sleek Dustbuster hand vac also has a 3‐stage filtration system to help ensure it effectively removes dirt and allergens from your home. It can be stored in three different ways. The Black & Decker Cordless Hand Vac has a rotating, slim nozzle with a wide‐mouth design. An on‐board brush and crevice tool is also included.

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Details Voltage 14.4 Air Watts 24 Watts Capacity 20.6 oz. Replacement Filters VF110 Power Source Cordless

Customer Reviews

Very powerful handvac My old Dustbuster finally gave out after 10 years. After reading reviews, I decided to get this model as a replacement. I was pleasantly surprised at how much more powerful it is compared to my old one. Plus the charge holds for a very long time.

Perfect for cleaning up after toddlers I purchased this cordless hand vacuum primarily to clean up my car and daughter's car seat. The first time I used this vacuum after charging for the recommended 24 hours, the battery lasted about 25 minutes. The instructions suggested to run down the battery completely during the first use. I vacuumed my daughter's car seat, and my entire car and the battery was still going strong. I like this lightweight model, and that it can be opened up and easily cleaned. There are no replacement bags or filters that you have to purchase. It has an extending tool that works great for getting into tight spots. The vacuum power is as powerful as my full size vacuum. It is loud, but it does a great job. I'm hopeful that this product will continue to perform well.

good, but... I would really like this hand vac, the problem is that it only holds a charge for a very short period of time. I've seen another review that said theirs held for a long time, and maybe it's just mine, but after charging it for 5 hours, it will only run for maybe 5 minutes.

Love This Product This dust buster is lightweight, but packs a punch for areas where it is awkward to use a full size vacuum cleaner! I would recommend this product for everyone! It is cordless, and charges easily using the wall adapter. It can work on carpet, hardwood floors and upholstery. This tool is perfect for cleaning baseboards. I recommend it whole‐heartedly.

Cordless Vac didn't hold a charge. Not happy with the Black and Decker Cordless Hand Vac. Only worked for 10 minutes and then cut off. It was fully charged, but wouldn't work. Had to return it. Very disappointed in this product

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5) DEWALT ½‐gal. Cordless 18‐Volt Wet/Dry Vacuum http://www.homedepot.com/p/DEWALT‐1‐2‐gal‐Cordless‐18‐Volt‐Wet‐Dry‐Vacuum‐DC515K/100609523#customer_reviewsModel: DC515K

Model: DC515K

$129.00

Product Features

Runs off of 18‐volt DEWALT battery packs for a long run time (additional battery packs sold separately)

0.5‐gallon tank with heavy‐duty latch is easy to empty and clean

Gore HEPA wet/dry filter traps up to 99.97% of dust at 0.3 microns

Dual clean‐up modes for debris cleanup with either the front utility nozzle or the extendable rubber hose

360‐degree side handle adjusts easily for preference and use in tight spaces.

Product Description This DEWALT Heavy‐Duty 1/2‐Gallon Cordless 18‐Volt Portable Wet/Dry Vacuum features dual clean‐up modes for debris cleanup with either the front utility nozzle or the extendable rubber hose. The Gore HEPA wet/dry filter traps up to 99.97% of dust at 0.3 microns, and the 360‐degree side handle adjusts easily for preference and use in tight spaces.

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Details Accessories/Parts Included

1 hour charger, 18V XRP battery

Air Volume (CFM) 0.5

Amperage (amps) 18

Built‐In Accessory Storage

No

Built‐In Drain No

Casters No

Color Family Yellows / Golds

Cord Length (ft.) 0

Filter Type Other

Peak Horsepower 0 hp

Product Weight (lb.) 6 lb

Reconditioned No

Returnable 90‐Day

Vacuum Capacity (Gallons)

0.5

Voltage (volts) 18

Customer Reviews

Above average portable vacuum I have been disappointed in all battery‐operated portable vacs over the years until I found this item. I use it primarily to vacuum my cars and it works well. I wind up using the extendable hose quite often as the bulky unit cannot get under the seats and in tight areas. However, the option to use the hose is one of the great features. I really have no major complaint and am very happy with this vac. It is a portable vac with powerful suction, exactly what I wanted. It is so much nicer to grab this for small jobs than any plug‐in vac. I'm hoping I can find a couple nozzle attachments to get into real small/narrow areas. I highly recommend.

Great little vac I bought this small vacuum because I needed to replace a Black and Decker Dustbuster. Needless to say, this DeWalt blows that Dustbuster to shreds, it's just crapola. You can tell that DeWalt actually spent some time designing this as it works great and actually sucks up what it's supposed to, wet or dry, which is also a nice feature. The ONLY thing that I would say is more of a nuisance on the DeWalt is it's a little loud, but not enough for me to want to return it, I just mention it because it's probably hard to put that much power into a quiet vac. But I would recommend it, it's great for small jobs around the garage and house.

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Dewalt 18v After all of the good reviews I bought it and found the following major flaws: Incredibly small suction area in the main (yellow) nozzle Almost useless toy black hose ‐ too short to reach anywhere No attachments to the hose‐ can't reach anywhere under a car seat etc. I picked up an old dust buster at the recycling center‐ a $40 replacement battery will make it a cheaper alternative‐Disappointed in Dewalt on this one.

Nice Product! Great addition to my shop for quick clean ups at the end of each project.

Excellent choice for hand held vac vacuum was easy to assemble (nothing to put together) light weight and no objectionable noise or vibration very easy to empty and clean . Only thing not in the instructions that i could find was if it is being used as a wet vac what stops it when full of water etc

Compact size is easy to handle and keep close by Well made, very practical to use compact vacuum for around the shop and garage as well as normal household use. Very versatile and tough. Can be handled by kids to clean up their messes. Found that suction lasts longer if filter is wrapped in a cloth to reduce clogging from fine dirt. A bit noisy when running but it's usefulness, toughness and utility balance off relatively high price.

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6) Hand‐holdable vacuum cleaner https://www.google.com/patents/US8595895?dq=8,595,895+vacuum&hl=en&sa=X&ei=ZATkVOGFEpK1oQS07oGYAg&ved=0CB0Q6AEwAA

Patent #: US 8595895 B2

Patent Abstract A hand‐holdable vacuum cleaner comprising: a motor coupled to a fan for generating air flow; a battery pack housing at least one rechargeable cell for powering the motor; a body with a handle; a dirty air duct with a dirty air inlet; and a dirt separating means located in a path of the air flow generated by the fan, wherein the dirt separating means comprises: a hollow substantially cylindrical dirt container with a longitudinal central axis arranged transverse the body; and an air inlet port to the dirt container, wherein the air inlet port is in communication with the dirty air duct, wherein the dirt container is rotatingly connected to the body to pivot, with the battery pack, about the central axis between a folded position and an extended position diametrically opposed to the folded position.

59

7) Handheld vacuum cleaner https://www.google.com/patents/US8069529?dq=8,069,529+vacuum&hl=en&sa=X&ei=mQzkVKD2Bsj8yQS1zoHwAQ&ved=0CB8Q6AEwAA Patent # US 8069529 B2

Patent Abstract A handheld vacuum cleaner including an inlet, an outlet, and a dust cup having an aperture. The dust cup is in fluid communication with the inlet and the outlet and is configured to retain debris collected by the handheld vacuum cleaner. A fan is configured to draw air through the inlet and the dust cup and to discharge air through the outlet. A door is adjacent to the dust cup and includes the inlet. The door is movable between an open position to allow a user to empty the debris collected within the dust cup through the aperture of the dust cup and a closed position to inhibit debris from being emptied through the aperture of the dust cup and to allow debris to be collected through the inlet and through the aperture of the dust cup. A biasing member configured to bias the door toward the open position.

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8) ELECTROLUX Hand held vacuum cleaner https://www.google.com/patents/US8225456?dq=8,225,456+vacuum&hl=en&sa=X&ei=2g3kVMOwFcOtyATJo4KQBA&ved=0CB0Q6AEwAA Patent # US 8225456 B2

Patent Abstract A hand held vacuum cleaner having a housing, a motor‐fan unit, a dust container, an air passage opening into the dust container and through which dust laden air is directed into the dust container, and at least one filter arranged after the dust container, as seen in the flow direction. The dust container has a first emptying opening, which is normally being covered by a lid and is sized such that it allows the dust collected in the dust container to fall out through the opening when the lid is opened. The dust container also has a second emptying opening. In one aspect, the second emptying opening is adapted to be fluidly connected to an external vacuum source via a connection. In another aspect, a similar device is provided, and adapted so the dust container can be emptied through the first emptying opening without removing the dust container from the vacuum cleaner. In another aspect, the invention provides a vacuum cleaner dust container having an air inlet, an air outlet, a first dirt outlet, and a second dirt outlet. The first and second dirt outlets are separate from the air outlet.

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Product research at MOMO LOLO coffee shop

The following survey was given to a local business (MOMO LOLO Coffee shop) that uses the Dirt Devil Easy lite cordless bag‐less handheld vacuum. Dirt Devil Vacuum Questionnaire Average Results

Please rate the following categories 0‐5 (0 is the worst performance and 5 the best performance) • Mobility of the vacuum 0 1 2 3 4 5 • Ease of operation 0 1 2 3 4 5 • Suction power 0 1 2 3 4 5 • Battery life/durations of use 0 1 2 3 4 5 • Overall quality of the vacuum 0 1 2 3 4 5

4 5 2 1 3

1) How long to do you typically operate the vacuum per use?

5 min

2) Are there any procedures you have attempted with the vacuum that it was unable to preform?

Getting dirt out of tight corners, even with crevice tool.

3) If there is something you would change/fix with the vacuum, what would it be?

More suction Handling tight corners

Additional comments:

Filter pain to clean, never gets clean which might be why it doesn’t have that much suction.

Personal interview

Name Collin Gerety

Occupation: Local business owner, MOMO LOLO coffee shop

Main thoughts:

The device needs an interchanging battery pack

Replacement battery pack must also fit an existing tool, so it is readily available on the market.

Biggest complaint was battery was continuously dead if previous user forgot to put pack on the charging machine.

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Sketch, Description, and Analysis of Improvements

Target Customers

Three primary groups of customers will likely use this sort of product. Requirements

for the product will be specialized to these types of customers, and may potentially be valued

differently depending on the customer and their circumstances. These types of customers are

listed and characterized below.

Individual user in a small home – This user will purchase such a vacuum for personal use.

Because they live in a small or shared dwelling, they may not own a larger vacuum. As a

result, a small cordless vacuum may see more use for a greater variety of tasks.

Family user – This group of users will usually consist of a family. Typically, the family will

already own a larger vacuum for cleaning carpets and what not, so the cordless vacuum use

will likely be more limited to specialized jobs with a heavier emphasis on hard to reach places.

Business – This group consists of employees who may use such a vacuum to maintain their

business. These users probably still own a larger vacuum for large jobs, but due to increased

traffic of a business, the cordless vacuum will experience even greater use than any other

customer category.

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Customer Requirements

Given these three categories of customers, requirements can be generated by use of

online reviews and interviews of members of these groups. Ideally, each requirement should

represent something that is fundamental to the functionality and purpose of the product.

Based on research in these areas, the most important customer requirements as well as

explanations of why they are important are listed below:

Mobile – Most households already own a traditional vacuum cleaner. The need for a cordless handheld vacuum is manifested by regions outside the reach of a traditional floor vacuum, such as vehicles, pet housing, and high up carpeted regions such as lofts. The vacuum should be lightweight and cordless in case a power source is not nearby.

Versatile – The vacuum should be able to reach in small cracks and crevices and still be able to clean up messes in these areas.

Sufficient Battery Life – A cordless vacuum cleaner is limited by a battery, as a power cord interferes with the purpose of the device. Therefore, batteries should be easily chargeable, and should supply power long enough to complete any job. Recharge time should also be reasonable in order to allow the vacuum to be fully charged for next use, and the battery should be able to hold a charge while not in use.

Strong Suction to Clean any Surface – Shag carpets may no longer be in style, yet any vacuum cleaner should have enough suction to clean even the most outdated living rooms. A great variety of surfaces can be found in homes, and a vacuum cleaner should be able to remove nearly all unwanted macroscopic particles from any surface.

Easy Maintenance and Cleaning – The vacuum should be easy to clean, empty, and maintain. Filters should be easy and affordable to clean or replace, and the vacuum should be easy to empty.

Affordable – A cordless vacuum cleaner will typically be a supplement to a traditional home vacuum cleaner, and as a result, they must be affordable in order for it to be reasonable to purchase one. Consumers will not pay the same amount for a product with fewer uses.

Safe – There should be no significant pinch points when operating the vacuum, such as opening and closing bags, filters, and other compartments. Additionally, the vacuum should be electrically sound with no risk of shocking the user.

Durable – The vacuum should last for several years. Motors should continue to operate at full strength, batteries should not suffer dramatic reductions in capacity, and parts should be resistant to wear over time.

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Identification of Areas of Improvement – Experimental

After multiple trials using the Dirt Devil vacuum and comparing its performance to that

of the Black & Decker, a couple of potential areas for improvement were identified, including

back flow and a lack of proper power. The extent of the trials performed will be covered

below.

The Trials – Procedure

In order to determine the performance of the Dirt Devil vacuum, a series of trials were

conducted in order to measure the effectiveness of the vacuum at cleaning up different types

of messes. As a comparison, a similar vacuum produced by Black & Decker, the Black &

Decker Dustbuster Bag‐less Cordless Hand Vacuum, also performed the same series of trials.

Trials were performed by testing the vacuum’s ability to pick up large, medium, and

small particles in three different types of surfaces. Large particles were dried beans, medium

particles were sprinkles, and the small particles were sugar. The surfaces tested were a

smooth table surface, a carpeted surface, and a carpeted corner. For the smooth surface and

the carpeted surface trials, a line roughly one foot long and about 3 inches wide was lain out

on the surface and was vacuumed by repeated passes. Values were taken of the amount of

particles that were picked up by the first pass of the vacuum. Different methods were used to

measure the remaining amount of particles. For the beans, the initial amount was just

counted rather than weighed. For some of the sprinkle trials, the remaining number of

sprinkles was measured as the mass became very small. A second value that was taken for

the smooth surface and carpeted trials was the number of passes that had to be taken by the

vacuum in order to clean up all of the particles. This measurement was not taken for the

corner trial, as it is more difficult to define a linear pass in a corner cleaning situation. For the

corner trial, an additional trial was taken using the extended crevice tool.

It should be noted that the vacuums were not fully charged during trials, as there was

not appropriate time to complete a full charge before testing.

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The Trials – Data

Small Particles‐Sugar

Carpet Line

Name Start Count

Amount Remaining

Total # passes

Dirt Devil 110g 6.7g 13

Black & Decker

110g 6.9g 5

Carpet Corner

Name Start Count

Amount Remaining

Total # passes

Dirt Devil 102.0g 2.1g 1

Dirt Devil (extended)

102.0g 0g 1

Black & Decker

97.2g 1g 1

Table Line

Name Start Count

Amount Remaining

Total # passes

Dirt Devil 103.3g 1.1g 2

Black & Decker

103.1g 6.1g 2

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Medium Particles‐Sprinkles

Carpet Line

Name Start Count

Amount Remaining

Total # passes

Dirt Devil 72g 70.1g 2

Black & Decker

72g 69.2g 2

Carpet Corner

Name Start Count

Amount Remaining

Total # passes

Dirt Devil 70.1 g 1 sprinkle 1


70.1 g 0 sprinkles 1

Black & Decker


Table Line

Name Start Count

Amount Remaining

Total # passes

Dirt Devil 70.1g 15 sprinkles 1

Black & Decker


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Large Particles‐White Beans

Carpet Line

Name Start Count

Amount Remaining

Total # passes

Dirt Devil 150 beans

0 beans 1

Black & Decker

150 beans

0 beans 1

Carpet Corner

Name Start Count

Amount Remaining

Total # passes

Dirt Devil 50 beans

0 beans 1


50 beans

0 beans 1

Black & Decker

50 beans

0 beans 1

Table Line

Name Start Count

Amount Remaining

Total # passes

Dirt Devil 150 beans

0 beans 1

Black & Decker

150 beans

0 beans 1

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Trials‐ Visual Representation

CARPET SURFACE

Small Particles

Before After

Medium Particles

Before After

Large Particles

Before After

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SMOOTH COUNTER SURFACE

Small Particles

Before After

Medium Particles

Before After

Large Particles

Before After

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CORNER PREFORMANCE

Small Particles

Black & Decker

Before After

Dirt Devil without crevice tool

Before After

Dirt Devil with crevice tool

Before After

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The Trials – Results and Potential Areas of Improvement

Generally, the two vacuums were relatively comparable in capabilities of cleaning up

messes. The most apparent differences came in the carpet surface line trial, where the Dirt

Devil required double the amount of passes to clean up all of the sugar, and the corner trials

where the extended crevice tool gave the Dirt Devil a noticeable advantage. All other trials

were very comparable, especially using the large particles, as the vacuums successfully picked

up 100% of the beans.

The apparent suction advantage of the Black and Decker was only visible in the carpet

line trial. This is likely due to the two vacuums not being fully charged. For short charges at

the beginning of the vacuum’s life, the Dirt Devil appeared superior, as nearly all tasks were

completed on a single 30 minute charge, while the Black and Decker had to be constantly

recharged. Results of these tests could have been very different if the Black and Decker had a

full charge; it is possible that it would have shown stronger performance throughout all the

trials.

The issue of back flow came from the rubber flap inside the nozzle of the vacuum that

is purposed to prevent particles to flow backwards and out of the vacuum cleaner. This valve

usually worked with no issues, however, on occasion, larger particles would become lodged

between the rubber flap and the nozzle, holding the flap open. As a result, some of the

particles that were vacuumed up would fall back out of the nozzle of the vacuum cleaner. This

is especially an issue because the ideal angle for operation of the vacuum cleaner is about 30

to 45 degrees from the horizontal, giving a gravitational force that opposes the suction and

becomes particularly troublesome when the valve is held open. It is difficult to determine

exactly how often this problem occurred. It did happen once during a series of roughly a

dozen trials, which would suggest an occurrence of 5‐10%; however, the sample size of trials

is far too small in order to determine a reliable number. As a result, the weight of this issue is

not entirely clear.

A second issue that could potentially need improvement was the suction of the

vacuum cleaner, especially when cleaning up very small particulates such as during the sugar

trial. The Dirt Devil took approximately twice as many passes as the Black and Decker to

remove all of the sugar from the carpet. Customer time is valuable, and this could indicate

that it could take twice as long to clean up messes, which would leave the Dirt Devil at a

disadvantage to other competitors. The most obvious potential cause of this is would be a

lack of proper suction.

It should be noted that there are likely many other issues that develop over time with

wear on a product. During the trials conducted, only issues present during the early life of the

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product could be identified. Typically, these sorts of issues should be weighted more heavily

when considering areas of improvement as they will be present throughout the life of the

product; however, issues that develop over time should not be discounted, especially if they

result in even greater detriments to functionality than problems present from the initial

purchase.

Identification of Areas of Improvement – Research and Customer Reviews

In order to better understand the issues that can arise over time, it is often best to

consult reviews of a product from customers who have been using the product for some time.

This can often be best established by means of consulting actual customers by means of

reviews as well as personal interviews and surveys.

Customer reviews showed that the number one concern with the Dirt Devil vacuum

was the battery life. While our battery proved to be satisfactory for initial tests, customer

reviews suggest that the battery life decreases severely to the point of operating for less than

a minute within a few uses of the product. Most customers identified that this was not

enough charge to complete most jobs. Most customer reviews do not identify other potential

areas for improvement, as reviews tend to be saturated with battery concerns.

Surveys were also conducted at the MOMO LOLO coffee shop in Fort Collins, where

employees regularly use the Dirt Devil cordless vacuum. Employees were happy with the

mobility and ease of use of the vacuum; however, they also identified the battery as being a

serious issue. A second issue that was identified was that the suction was not sufficient to

clean up most messes. The owner of the MOMO LOLO coffee shop was personally

interviewed, and also identified concerns with the battery life along with the suggestion of an

interchangeable battery pack. The shop also uses a similar Dirt Devil vacuum that has a cord

and was overall very happy with its performance. Further details of these interviews can be

found in the Research section of this report on page 59.

Review Comparisons of other Vacuum Cleaners

Research was done on a total of four other vacuum cleaners. One of those vacuum

cleaners, the Black & Decker Dustbuster Bagless Cordless Hand Vacuum was tested in parallel

with the Dirt Devil. Aside from physical trials, the four vacuums were compared by means of

reviews and listed features. The information used for these comparisons can be found in the

Research section of this report. These vacuums are listed below:

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Eureka Rapid Clean Pet Cordless Handheld Vacuum, 80A

Black & Decker 14.4V Cordless Hand Vacuum

Black & Decker Dustbuster Bagless Cordless Hand Vacuum

DEWALT ½‐gal. Cordless 18‐Volt Wet/Dry Vacuum

In terms of affordability, the Dirt Devil is the most affordable of the group at a price point

of $16.49. The Black & Decker Dustbuster comes in at a close second with a cost of $17.99.

The Black & Decker 14.4V as well as the Eureka jump into the $30‐60 price range. The

DEWALT is a whopping $130.

Most of the other vacuums appear to have greater suction than the Dirt Devil. At full

capacity, it was fairly obvious that the Black & Decker Dustbuster had greater suction than the

dirt devil. Reviews generally suggested that the Black & Decker 14.4V also surpassed the

suction of the Dirt Devil. The Eureka was built more specifically to handle pet hair, so it’s easy

to imagine that it likely also has adequate suction, however, it is difficult to determine this

from the reviews as many of the reviews are more centralized around the vacuum’s reliability

over time. Both the Eureka and the Black & Decker 14.4V vacuums use 14.4V power supplies,

which may contribute to the suction strength. The DEWALT carries a hefty 18V battery, and

provides superior suction, according to reviewers.

Battery issues seem to be a common issue with all of the vacuum cleaners; however, the

Dirt Devil is without a doubt the most troubled in this regard. Some of the poor reviews may

be related to improper battery charging protocol, as batteries tend to underperform when not

charged properly. It is clear though that this is not the issue with the Dirt Devil due to the

amount of complaints. The DEWALT did not seem to display battery issues, as an obviously

higher quality universal DEWALT interchangeable battery is used.

The Dirt Devil appears to be the smallest of the four vacuums. The Black & Decker

Dustbuster is comparable in size, but slightly larger and more bulky. The Black & Decker 14.4V

also has a crevice tool; however, it appears to be significantly larger than any of the other

vacuums. While we did not get to work with the Eureka, the head is a rather unusual shape,

so it may not be particularly efficient in reaching tighter areas. The DEWALT is very large, and

appears to have a relatively small nozzle area, making tight region clean up difficult, even with

the crevice tool.

The most notable feature of the Dirt Devil is probably the crevice tool. All the vacuums

except for the Black & Decker Dustbuster also feature a similar feature. Both Black & Decker

vacuums advertise easily washable filters, and the DEWALT features a wet/dry filter

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advertised to be capable of trapping 99.97% of dust at 0.3 microns. The Eureka has multiple

features that specialize in removing pet hair.

The Dirt Devil seems to have the lowest working lifetime. Reviews for the Eureka also

seem to display durability issues. Both Black & Decker vacuums appear to have long overall

lifetime. The DEWALT also appears to be very durable, and maintain strong suction and

battery life.

Comparisons with the Customer Requirements

Mobile – This requirement was generally fulfilled well with the current design. The vacuum is

reasonably lightweight, easy to maneuver, and is cordless.

Versatile – The crevice tool was extremely helpful in cleaning the corner. The surveys at

MOMO LOLO coffee shop did suggest that a better crevice tool may have been helpful. This

requirement was partially fulfilled.

Sufficient Battery Life – This requirement was not fulfilled. While battery life may be

satisfactory at the beginning of the product life, reviews show that the operation time is

atrocious after a few uses of the vacuum.

Strong Suction to Clean any Surface – The suction of this vacuum cleaner was sufficient for

smooth surfaces, however, reviews and interviews seem to suggest that the suction does

decay over time. Experimental trials also revealed difficulties in cleaning carpet surfaces with

smaller particles.

Easy Maintenance and Cleaning – The emptying of the dust cup and removal of the filter is

very easy, however, cleaning the filter proved difficult. For mechanical and electrical parts,

the device is not constructed in a way where replacement of parts is easy.

Durable – Reviews generally suggest that the motor does not last long before dying out, and

the battery capacity plummets severely after purchase. This requirement has not been well

fulfilled.

Affordable – The dirt devil appears to be the cheapest vacuum on the market for this

particular class of vacuums. While value may come into question, this requirement does

appear to be met.

Safety – Electrical components seem to be well isolated. Under standard use, the chance for

any electrical shock should be low. The only potential pinch point is the removal and

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replacement of the dust cup; however, this does not seem to be of great concern. This

requirement has been met.

Further analysis of how the dirt devil, as well as competitor vacuums, meet customer

requirements can be found in the chart below. Information is also provided identifying

correlations between specifications and target values for the various specifications of a good

hand vacuum based on what is currently available.

Specifications the device must meet based on customer requirements:

Cost of vacuum (dollars)

Total weight of vacuum ( pounds)

Number of parts (number)

Time to recharge the battery (hours)

Duration of battery life per use (minutes)

Machine washable filter (Y//N)

Number of uses between changing the filter (number)

Voltage supply (Volts)

Width of the nozzle for small space removal (mm)

Target particles removed (Y/N)

Number of pinch points (number)

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This chart tells us that the most important specification for customers is battery life.

Customers require that a vacuum will operate for at least 5 minutes. The number to beat in

order to outperform all competitors is 40 minutes. Safety also scored high in this analysis.

Although, it should be noted that the actual risk of injury from these vacuums is quite low.

Other high scoring specifications are minimum nozzle width, ranging from 9mm to 45 mm,

and weight, ranging from 5 lb to a delighted value of 1.7 lb.

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Concepts to be Improved Upon

Notable issues that arose from the consumer reviews, interviews, and test trials were

as follows:

Battery capacity

Motor strength

Suction

Filter maintenance

Crevice tool effectiveness

Valve backflow

After identifying these issues, a Brainwriting technique was employed to try and generate

concepts of potential solutions to some of these issues. This was completed by passing a

sheet of paper among the team members, where the first team member would put down

three ideas, and then pass the paper to the next team member. That member would then

either build on those ideas, or generate new ideas. This was done for each team member.

The results are shown below.

Brainwriting Activity

Improvements Idea 1 Idea 2 Idea 3Heidi Replacement battery

packs Better crevice tool Improved battery

function

Bryce Compatible with other tools, larger vacuums

Flexible crevice tool Lithium Ion Batteries

Trent More streamline front shaped nozzle

Crevice tool attachments

Stronger motor

Krystal Change the design of the fan blade

Use a different filter or different material to improve air quality

Change the design of the vacuum valve to reduce back flow.

The ideas that were chosen to be conceptualized were a more versatile crevice tool,

interchangeable battery packs, and a modified fan and drive system to create more suction.

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Potential Concepts for Improvement

Versatile Crevice Tool One concept is to make a more versatile crevice tool that has an even smaller forward

profile to fit in particularly tight spaces. In order to allow the tool to reach a greater variety of angles, the crevice tool could be attached to a flexible hose, similar to the DEWALT vacuum. The smaller tool would likely pick up less material; however, this should not be an issue as the tool would only be used in small regions where there’s not a large area to clean. The hinged attachment could still be used. The rigid crevice tool would instead be replaced by a compressible hose. In order for the crevice tool to be folded into its closed position, the hose would need to be compressed along its long axis, and the tool head would clip in where the end of the current crevice tool clips in on the current design. When the tool is extended, the hose would be stretched out of the compressed position and then turned in any direction, allowing for winding around corners and edges to even the most difficult and hard to reach places.

Interchangeable Battery Packs

An obvious and very prevalent issue with this vacuum as well as many other cordless

vacuums is battery life. Many power tools use exchangeable battery packs that can be

charged away from the tool, and then attached to the tool for use. These batteries are

typically standardized and will work across multiple devices. Additionally, multiple batteries

can be charged before use, and then used one after another in order to multiply the running

time of the device by the amount of pre‐charged batteries. Once a battery’s capacity has

been reduced due to many recharges, the battery can be replaced with a fresh new battery.

This concept could be applied to Dirt Devil vacuums as well, possibly even with the addition of

compatibility with standard rechargeable tool batteries already on the market, such as the

DEWALT vacuum that was compared to above. Ideally, this solution would not need to be

particularly expensive if the customer already owns one of these batteries.

Modified Deeper Fan and Drive System

One potential solution that may create more suction is a larger fan driven by a more

powerful motor. The fan is responsible for forcing air from inside the compartment of the

vacuum out through the side air vents. As this air is vacated from the fan region, more air

rushes in through the nozzle and the filter to replace it. A faster, larger fan will move more air

at a faster rate, creating a larger suction. The motor replacement should be simple as it is

easy to imagine that the current motor is not particularly powerful, and a stronger, similarly

sized motor should not be too difficult to find. Additional batteries may be necessary to

create a larger voltage to drive the motor. The fan can be deeper, allowing it to scoop a larger

amount of air and direct it out of the inner compartment, creating a greater vacuum to pull air

through the system.

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Decision Matrix

The Decision matrix compares these three potential concepts to the stock Dirt Devil

vacuum and determines a score for each improvement based on how the suggested

improvement will affect the vacuum’s ability to meet the customer requirements. The table

below shows this analysis.

Original Design Alternatives Interchangeable Battery Packs

Versatile Crevice Tool

Modified Fan and Drive System

Mobile 10 0 0 ‐

Versatile 9 ‐ + 0

Battery Life 18 + 0 +

Suction 15 0 + +

Ease of Clean 14 + 0 +

Affordable 11 ‐ ‐ ‐

Safe 13 0 0 0

Durable 10 + ‐ ‐

100 Total 1 0 0

Weighted 64 27 63

The Improvement

The decision matrix determined that the interchangeable battery pack would yield the

greatest overall performance of the vacuum as a whole. The proposed design would remove

the battery from the body of the vacuum, and transfer it to an external location. The stock

purchase of the device would come with an external battery of similar charge storage to the

current device. The battery ideally should be of higher quality, preferably lithium ion;

however, if the same price point needed to be met, a similar battery could be used, as this

design would allow for further improvements and easy replacement of batteries.

The device would allow for two battery options. A charging port would be placed at

the base of the handle of the vacuum cleaner. This charging port would be at the base of the

female connection of a larger rectangular adaptor port that will provide mechanical support

to the battery. The two options would be the stock battery manufactured by Dirt Devil;

however, other adaptors would also be manufactured to allow the use of standard

rechargeable batteries used by other brands. The adaptor pieces, nicknamed the “Hermie,”

would slide into the larger rectangular port, making a connection with the charging port. If

necessary, a voltage transformer would be present in each adaptor that would coincide with

the voltage of the adaptor battery in order to match the proper voltage with the vacuum

itself. Additional latches would be present to secure the adaptor in place.

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Figure 31: Stock battery pack installation

This would allow for customers to use more expensive batteries that they already own

to power their vacuum cleaners. If they don’t own a power tool battery, they still have the

option to purchase one if they are not satisfied with the stock battery. If they are content

with the stock battery, but want to use the vacuum on a more frequent basis, they have the

option of purchasing multiple external batteries which can be charged concurrently.

The battery at the end of the handle would add a significant amount of mass to the

handle of the vacuum. This should not be an issue though, as the moment from that mass will

help to balance the moment from the mass of the motor and the forward casing elements of

the vacuum. As a result, the overall vacuum should actually be more balanced than before

relieving strain on the user’s wrists.

The cost of this system should not be significantly greater than what is currently

available. The same batteries could still be used; the only difference is their location in the

vacuum. Material costs may increase slightly in order to manufacture the junction between

the adaptor and the battery. The Hermie adaptor would be sold as a separate product with

different models that are compatible with a variety of manufacturer power tool batteries.

81

The user would simply purchase the proper Hermie that matches their chosen power tool.

This alternative would be completely optional, and the vacuum would still function without

the Hermie adaptor.

Figure 32: Hermie Adaptor

This particular model was designed with DEWALT rechargeable batteries in mind, the

same battery used in one of the comparison vacuums. The DEWALT had the best customer

reviews by far out of all the vacuums. It really is in a higher class than any of the vacuum due

to its price. This adaptor is an attempt to bring the battery power of the DEWALT to a much

more affordable vacuum cleaner. In order to make the Hermie adaptors work with many

types of batteries, it may be necessary to expand the handle of the vacuum cleaner or extend

the adaptor out so that larger batteries can still fit. Regardless of this detail though, the

principles still apply.

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Figure 33: Hermie Adaptor details

83

Teamwork Analysis

Team Contract

84

Meeting notes

01.25.15 Meet and greet

Assignment #2 group portion

Schedule meetings for future dates

Schedule group meeting with Bob

01.27.15

Discuss when all requirements should be started and completed.

Finish assigning tasks

Make a timeline/chart that describes exact dates for all aspects within the project.

Schedule all future meetings to ensure all group members can participate

01.31.15

Re‐designate project duties

Make new Gantt chart with Microsoft project

Compare Dirt Devil and Black and Decker vacuums with three different size particles on two different surfaces

Disassembly of Dirt Devil

Photos of comparison tests

Photos of disassembly

02.11.15

Create survey for MomoLolo coffee shop

Finalize part names for report

Creo prediction for part completion

Finalize which creo parts for design.

02.18.15

Brainwritting activity

Gantt chart update

Creo update

02.28.15

Completion of new improvement section

Final compiling of information

Proofread and complete entire project

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Team Health Assessments

Date: 1/31/15

Measure SA A N D SD NA

1 Team Mission and purpose are clear, consistent and attainable X

2 I feel that I am part of a team X

3 I feel good about the teams progress X

4 Respect has been built within the team for diverse points of view

X

5 Team environment is characterized by honesty, trust, mutual respect, and team work

X

6 The roles and work assignments are clear X

7 Team treats every member’s ideas as having potential value X

8 Team encourages individual differences X

9 Conflicts within the team are aired and worked to resolution X

10 Team takes time to develop consensus by discussing the concerns of all the members to arrive at an acceptable solution

X

11 Decisions are made with the input from all in a collaborative environment

X

12 The environment encourages communication and does not “kill the messenger” when the news is bad

X

13 When one team member has a problem others jump in to help X

14 Dysfunctional behavior is dealt with in an appropriate manner X

15 When someone on the team says they are going to do something, the team can count on it being done

X

16 There is no “them and us” on the team X

17 Our team cultivates a “what we can learn” attitude when things do not go as expected

X

86

Date: 2/11/15






X


X






X


X


X




X



X

87

Date: 2/28/15






X


X






X


X


X




X



X

Disassembly and Reassembly of the Vacuum

Disassembling the vacuuming was done with extreme care with possible hopes of

reassembling and having a functional vacuum. In order to properly measure all the

dimensions for replicating the parts in Creo, some of the parts had to be removed from their

original position. Many parts were tightly held together, and had to be pried apart. There

were many lumps of glue holding wires and circuitry in place that we were forced to break in

order to fully disassemble the vacuum. This seemed to pose no real threat in the reassembly

of the vacuum. The next part that we had to pry apart was the Power Switch Casing and

Power Switch from the circuit board. In the process of removing the switch, the baseplate

beneath it formed a fault along the three switch contact plates, and broke in half. As a result,

permanent reassembly would be exceptionally difficult, as it would require the repair of the

switch baseplate. We can get the motor to turn on and rotate the fan by connecting the

battery pack directly to the motor, but to get the vacuum to function permanently while

retaining the original circuitry and recharging functions, delicate reassembly of the switch and

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some regluing would be necessary. The following table shows the disassembly and reassembly

process of the vacuum.

Notes on Disassembly

Disassembly Reassembly Notes on Reassembly

Dirt devil removed from box.

The crevice tool and brackets, valve and filter assembled perfectly.

Front casing, filter, valve easy separation. Crevice tool with brackets more difficult.

Difficult to replace the broken piece on the circuit board where the power switch and power switch casing were attached.

Minimal difficulty removing the screws and separting the left and right casing shells.

Power switch casing and switch were attached, copper and metal plates assembled back into power switch.

Detail inspection of the layout of the interior parts.

Had to use wire and glue to reattach power switch. Circuit received no signals before or after complete.

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Individual Team Member Comments on Group Performance

Trent McNamara‐

In Conclusion the team worked well together. Our strengths were discussing ideas as a

group which always ended with the majority of the group in an agreement. Another strength

we had was solving problems and dividing up work evenly. Each group member put forth a

similar amount of time on their section and was satisfied with the result. We didn’t have many

problems arise but when we did we, as a team would address these issues in a way that was

non confrontational but also ended in resolution. Some of our weaknesses were completing

work on time. Multiple members of the team missed deadlines on the completion of their

work which resulted in delays and eventually a long couple of meetings in the lab. From these

weaknesses we learned to keep ahead of our work and to hold other members of the team

Removed all interior parts for further inspection.

Repositioned all parts into the appropriate places within the left casing shell. Including spring and filter button.

System turned on while power switch was in on position. Also, the light was activated for charging.

Placed the right casing shell on, some difficulty getting all wires back into correct places.

During final dissassembly, circuit was broken to remove power switch and power switch casing.

Vacuum fits together nicely, power button moves freely, front casing attaches great, but no power to the vacuum.

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accountable for their potion of the project. Overall the team worked well together and the

project was completed on time with very little issues.

Heidi Potton‐

Our initial plan for the project included many portions of the requirements being done

by several members of the team. After our meeting with Bob, we decided to take his advice

and work on the strengths of each team member and separate the tasks more individually.

Once we did this, we each concentrated our efforts in the areas where we were most

qualified. This provided our team to meet the requirements of the project most efficiently.

We did have some deadlines that were not meet, so if we had not appropriate delegated the

projects requirements in the beginning, we would have had difficult time producing a quality

report within the deadline. Overall, we had great team dynamics and worked well together.

Bryce Wilson‐

I’m very happy with our team’s overall performances. There really were no instances

that arose where it felt one team member was not fulfilling their duties, or that we were

unhappy with a team member’s efforts towards the projects. There were some issues trying

to meet deadlines, however, we tried to plan to finish the project early as a precaution in case

delays arose. This worked out quite well, as even though the last week has been busy, it has

been reasonable. I think better planning and efforts to keep up with deadlines will be helpful

in the next project. I believe spreading out tasks and responsibilities over greater lengths of

time may be helpful in the future, as well as aiming for a steady, but balanced workload,

rather than an intense final push to complete the project. All team meetings were very

amicable, and no serious conflicts arose. I believe our team got along very well, and I look

forward to working with them on the next project.

Krystal Tamayo‐

Overall, I am very proud of this team. In the end, every member of this team was

responsible and got their assigned tasks completed. However, we did have some delays in our

project because some of us were not able to complete our tasks on time. Communication

really helped us get back on track because everybody was aware of the delays and what

needed to be done to make up for the time lost. The “buddy system” also helped to stay on

track because there were a couple of situations where a team member needed assistance

from another team member in order to complete a task. Nevertheless, as with any other team

we did not agree on everything but we were respectful of each others’ thoughts. We also did

not emotionally attach to the problem, instead we discussed the problem professionally and

compromised. I can genuinely say that our team had effective group dynamics.

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Reflection on Project Delays

As can be seen in the Project Plan section of this report, there were a few set backs

that pushed back our due dates. The first most notable setback can be seen between the

1/31 Gantt chart and the 2/11 Gantt chart between the Research Competitors task and the

How the Vacuum Works task. The extension on the research competitors had to due with an

increase in the amount of content we had planned to incorporate into that section of the

report, most notably, the customer interviews and surveys at the MOMO LOLO coffee shop.

These interviews took time to complete in order to allow employees to use the vacuums and

report on the surveys.

The setback for the How the Vacuum Works section was due to unexpected

dependencies on the CREO models being completed. As time progressed, we realized that it

would be beneficial to include renderings from the completed CREO models to supplement

the description of the functionality of the vacuum. For this reason, completion of this section

required a completion of all of the CREO models.

It did appear as if some delays could potentially arise in the production of the CREO

models as well. We had assigned a majority of the CREO work to one individual after

consulting with Bob on our labor distributions. The amount of work involved did end up

taking more time than expected. In order to try and catch up in this area of the project, the

buddy system was employed and a second group member stepped in to complete the CREO

parts for many of the internal pieces of the vacuum. As a result, the CREO models were

completed only a couple of days passed the deadline, and no major repercussions were

encountered.

A setback that was not as well illustrated in the Gantt charts was a very difficult

academic week for most of our group members from February 23rd through the 27th. Several

of our group members had three exams that week, so virtually no work was completed on the

project during that week and the weekend preceding it. We were able to recover by putting

in a 10‐hour day on the 28th as a group, and an additional 5 hours of work on March 1st. These

days were long and fairly difficult, but being in the same room while working individually did

allow us to consult with one another when questions arose, which was beneficial towards

maintaining congruence between all of our parts of the project. For the next project, it may

be beneficial to plan out when exams for other classes are occurring so that we can plan

accordingly.

The majority of the work on the improvements section was also completed later than

we expected. This was partially due to delays in determining the feature to be improved

upon. We had hoped to wait to choose an improvement until after the in class lectures about

generating concepts and selecting concepts using a decision matrix. Unfortunately, we were

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hit with the heavy exam week following those lectures, so this plan did not work out quite as

well as we had hope. The recovery of this delay was a large part of the efforts that went in to

the February 28th meeting.

Future planning

For Project 2, we will try to put even more thought into the project plan. We will try

and determine when we all have exams before creating a plan, and attempt to plan our

deadlines around obligations for other classes. As we did in this plan, we will once again try to

accomplish our tasks early in order to allow for unexpected delays. While we did try to use

the buddy system in this project, we will attempt to be more formal about it in order that we

can immediately jump in to help other group members when they become overwhelmed.

Distribution of tasks between members certainly was helpful; however, flexibility in being able

to assist other group members when help is needed is crucial to a group’s success in

accomplishing tasks on time. Last but not least, full and complete understanding of the

project requirements from the very start will allow for early determination of task

dependencies and for prompt conclusion of tasks with all necessary elements.

Documents

Mech 202 Project 1