The Floor Scrubbing Process

Published Date: 02 Nov 2017

Scrubbing system is used to clean our home especially in toilet and bathroom to remove the dirt. The basic floor scrubbing process is by using conventional floor scrubber which is not ergonomic to handle and required hand force towards the floor during the process. There are few commercially available automated cleaning and polishing machines but there are either not cheap or not intended for household and low duty application. There is a vacancy in the Malaysian market for this type of product. Below are the examples of High duty polishing and conventional floor scrubber which is currently being used in Malaysia.

Handle floor brush

High Duty Polishing Machine

Figure 1.1.1 Types of floor scrubbing tools

Problem Statement

The conventional scrubbing method which performs manually using simple tools does not usually provide satisfactory scrubbing. Since it performs manually, scrubbing is limited only to the area that can be reached by the tool and this may affect the desired cleanliness. The existing scrubbing tools are designed for general purpose cleaning that do not take into account the efficiency of cleaning of locations hard to reach and the ergonomics of handling during the process.

Typical injuries affect the back, shoulders and arm. The injury data show that the area’s most commonly affected by these ‘musculoskeletaldisorders’ in cleaners are the back, shoulder, upper arm, wrist/hand and fingers. Common types of disorders are Sprain sand strains, injuries to muscles, intervertebral discs and other structures in the back, Injuries to soft tissues such as nerves, ligaments and tendons in the wrist and elbow.

A new product, Electric-Powered Scrubber should be developed to provide optimum efficiency and offers greater flexibility that suitable for any household cleaning task. The existing scrubbing system are mainly operated manually at Malaysia, consume considerable amount of time and manpower to complete the process of cleaning at house.

Objectives

To generate and establish design objective for a new scrubbing system based on feedback from potential customer.

To design an Electric Powered Scrubber for household applications that is efficient, safe and user friendly.

To build a working prototype model with the function as per the design concept.

To conduct performance measure test of the prototype in real life upon completion prototype model built.

Methodology

In order to get the initial view of designing the machine, a public survey will be done to know the problem and demand from potential customers, so that the customer requirements could be translate into a technical description of what needs to be designed. Data that will be obtain from the survey which will be analysed, in order to understand the customer’s needs. The next step is to list all requirements according to their classes of function. Furthermore, all of the customers’ requirements will be evaluated to analyse the important of each customer’s requirements and generating a weighting factor. The customer requirements are also will be used to evaluate the competition and generate engineering specifications to set target for product performance. Results from the specifications definition are then will be used to generate and evaluate concepts of the product design, finalised the 3D model and proceed to build physical working prototype. Upon completion of prototype model, performance measure test shall be conducted to measure the performance and efficiency in real life, thus will be concluding on the future enhancement that can be done for a better quality and results.

Scope

This invention is target to household customers who are involved in house cleaning process with the objective to reduce the ergonomic issue and increase the efficiency of scrubbing.

Flow Chart of Project Activities

Figure 1.6.1: Flow chart of project activities

CHAPTER 2 LITERATURE REVIEW

Introduction

There was a time when scrubbing floors required plenty of water, soap, and a strong back the only way to really scrub a floor effectively was to get down on hands and knees and slowly work across the entire floor or by using conventional floor scrubber. This requires a lot of time and energy to perform [1].At Malaysia (domestic), for house hold application the most common tool being used to clean the floor is conventional floor scrubber. There is no product designed specifically for house hold application or low duty application. In the same time, there are also few high duty electric floor scrubbers available at market for a bigger scale usage.

Floor Scrubbing Process

Install/use the appropriate brush into the bottom of the floor scrubber, depending on the floor and the type of job that need to do. For example, if it is marble floors, a softer cloth pad or sponge attachment is appropriate. If its linoleum floors, a tough bristled brush is more suitable. [5]

Prepare a storage tank which will be used to mix the detergent/solution and water for scrubbing process based on the recommended floor cleanser. [5]

Work it evenly across the floor by scrubbing, stepping backwards from right to left, until entire surface area of the floor is covered by using solution from the storage tank simultaneously.

Upon completion of the scrubbing process, the water in the storage tank is to be disposed and clean the tank for the use for next time.

Floor Scrubbing Tools/Equipment

Scrubber

Detergent / Cleaning Solution

Types of Scrubber

Manual floor scrubber

The ultimate manual floor scrubbing is human. People can clean their floors on their hands and knees with a bucket and soapy water, with a hand scrubber or handle floor brush. The standard for scrubbing floors is clean away all the dirt and strains [3]. This requires extra forces by hand during the scrubbing process for an efficient and good result of scrubbing. In the same time, the way of handling the tools during the cleaning process usually not ergonomics which causes stains to the customer resulting muscle pain or joint pain during or after the process. Apart of that, this process also consuming a lot of time to complete the cleaning process depends on the courage floor area.

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Hand Floor Scrubber

Hand Floor Brush Scrubber

Figure 2.3.1.1 Types of Manual floor scrubber

Advantages:-

Lightweight-easier to handle

Smaller In size

No additional power source required

Do not takes space for storage

Disadvantages:-

Consuming time

Not Ergonomics-potential muscle injury or joint paints

Efficiency depends on the amount of force being applied

High Duty Floor Scrubbers

History of floor machines

The first useful electric-powered floor machines date back to the early 1900s. Coincidentally, this was about the same time vacuum cleaners were introduced, which we discussed last month. The first floor machines were known as "divided-weight" machines. With these machines, the bulk of the weight of the machine was on its rear wheels, which remained on the floor during operation. The buffer rolled in a push-pull fashion over the floor for both scrubbing and polishing. These early machines used brushes made of Tampico and Bassine, vegetable fibres used for centuries for floor scrubbing and polishing. To polish wood floors, carnauba wax would be applied to the floor, and then polished to a shine by going back and forth over the floor with the buffer. Divided-weight machines lacked sufficient speed, weight, and pressure over the brush to produce a high-gloss shine, and they were hard to maneuver. The major benefits for the user were that the machines were faster and less strenuous to use than polishing a floor by hand. [2]

High Duty Floor Scrubbers

With a basic design that was somewhat like a push lawn mower, these early models of the automatic floor scrubber contained a well for water and soap, as well as jets that could squirt the cleaning mixture onto the floor. A set of rotary brushes worked the cleansers into the facing of the floor, effectively lifting dirt and scrubbing the floors clean. [1]

Figure 2.3.1.2 Types of High Duty floor scrubber

Advantages:-

It is no longer necessary to get down on hands and knees to scrub the floor

the job can be done in much less time

the floor should dry quicker, meaning less waiting time to resume normal activities

Disadvantages:-

Heavy-cannot be lifted

Consuming a lot space where

scrubbing is limited only to the area that can be reached by the machine

Takes huge space for storage

Consuming electric power

Require regular maintenance

Expensive

Low Duty Floor Scrubbers

A new technology has evolved over the past few years that are certainly giving the old technology uses a wide-area squeegee that applies cleaning solution to floors. The system is much easier to use and does not require the time and training of conventional floor care machines. Requiring no harsh scrubbing action and helping to safeguard the floors’ finish and reduce refinishing cycles. [1] The size of the scrubber itself is smaller than high duty scrubber and lightweight making it is suitable to be used at household level. Unfortunately, this low duty scrubber is not available at domestic level, means that there is still a good market at Malaysia.

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Figure 2.3.1.3 Types of Low Duty floor scrubber

Advantages

It is no longer necessary to get down on hands and knees to scrub the floor

The job can be done in much less time

Smaller In size

Do not take space for storage

Lightweight-easier to handle

Disadvantages

Consuming electric power

Require regular maintenance

Expensive than the hand scrubber /handle floor brush

Detergent/Cleaning Solution

The main job of most cleaners/detergent is to clean floors. The principal reasons for floor cleaning are [6]:

To prevent injuries due to tripping or slipping. Injuries due to slips and trips on level floors are a major cause of accidental injury or death. Bad practice in floor cleaning is itself a major cause of accidents.

To beautify the floor.

To remove stains, dirt, litter and obstructions.

To remove grit and sand which scratch and wear down the surface.

To remove allergens, in particular dust.

To prevent wear to the surface e.g. by using a floor wax or protective sealant.

To make the environment sanitary e.g. in kitchens.

To maintain an optimum traction e.g. for dance floors.

2.4 Performance Measurement Test

Test is to be conducted upon completion of final working prototype if the model can deliver all the design specification and customers’ requirement that will be analysed in selected engineering specification on the next chapter.

CHAPTER 3 METHODOLOGY

3.1 Introduction

Engineering design is the systematic, intelligent generation and evaluation of specification for artifacts that’s from and function achieve stated objectives and satisfy specified constraints. The definition of design states that the design specifications are found as the result of systematic, intelligent generation. However, at the same time, there are techniques and tools we can use to support our creativity, to help us think more clearly, and make better decisions along the way. These tools and techniques are not formulas or algorithms. Through this chapter, reader will be presented those places in the design process where particular tools and methods can be useful to manage the design of electric powered scrubber.

Development of engineering specifications (Quality Functional Deployment)

In this stage the focus is to understand the problem to be solved. In order to get good engineering specifications, it is important for the design team to understand the problem to be solved clearly. There are many techniques used to generate engineering specifications, however for the development of electric powered scrubber, Quality Functional Deployment or QFD method is used. At the end of the QFD exercise a chart known as House of Quality as shown in Figure 3.2.2.

The basic idea of QFD is to create a link between the attributes that the customers voice and design them based on parameters from which the specific contributing actions and responsibilities of functions can be identified. The structure is organized and is often termed as the House of Quality. It is useful when there is involvement of cross-functional teams. The structure of House of Quality is built in four steps:

First house of quality–Customer’s House

Second House Of Quality – Company’s House

Third House of Quality – Process House

Fourth House of Quality – Process Control House

Conceptual design

Plan for the design process

Identify who the customers are

Generate customers’ requirements. What do they want?

Evaluation competition. How is it done now?

Generate engineering specifications. How will the requirement be measured?

Decompose into sub problems

Design Review

Terminate

Set targets. How much is good?

Figure 3.2.1 The engineering specifications development phase of the Electric Powered Scrubber design process

(vii)

(vi)

(ii)

(ii)

(iv)

(iii)

(v)

(ii)

(i)

(i)

Users

Customer requirements

Weighting factor

Target /existing product

Relationship between customer requirements and engineering specifications

Achievement of the product

Competitors’ evaluation

Competitors

Technical descriptions

Relationship

between

Technical descriptions

Figure 3.2.2 The house of quality or QFD diagram layout

This is the house of process control and constructed in the control phase. Its aim is to find the control variables used to satisfy customer needs. It may not be necessary to construct all four houses of QFD. It should be used to meet customer requirements from the development stage to the delivery stage and it should agree on the measurement systems and performance specifications to improve the company’s strategic competitiveness. By including the steps to improve on both spoken and unspoken requirements, it helps gain a competitive advantage.

3.2.1 Identifying the customers

In order to translate customers' requirements into a technical description, the first task is to determine exactly who the customers. For most design situations there are more than one group of customers. However, the most important target group will be the consumers or users of the product. Consumer is not the only customer in most design situation especially in the industries. There is designer management, manufacturing personnel etc. also that actually needs to be considered as a class of customer because there are many other factors that need to be highlight.

3.2.2 Determine the customer requirements

After the customers have been identified, the next goal in QFD method is to determine what to be designed. To answer that question it is essential to know what the customers want. Based on the customer survey on product quality to determine what requirement should have in quality product published in TIME, Nov 13, 1989 as shown in table 3.1 below, we can outline some typical requirements for a customer. Typically as shown in the table, the consumer want a product that work as it is should, acts a long time, easy to maintain, look attractive and has many features. Once the customer requirement is identified it will be list down in section (i) as shown in

Table 3.1 Result of a customer survey on product quality: What determines Quality? (TIME, Nov 13, 1989)

Essential

Not essential

Not sure

Work as it should

98

1

1

Lasts a long time

95

3

2

It easy to maintain

93

6

1

Looks attractive

58

39

3

Incorporates latest technology

57

39

4

Has many features

48

47

5

3.2.2.1 Collection methods for customers' requirements

Collecting information from customer is the key to the QFD method. There are essentially three methods commonly used: observation, survey, and focus groups (Ullman, 1997). Observation is done by observing customer using the existing products, so that the requirement can be founded and understood. Survey is generally used to gather specific information or ask people's opinions about a well-defined subject. Survey used questionnaires that are carefully crafted and applied either through the mail, over the telephone or in face-to-face interviews. The focus group technique was developed to help capture customers' requirements from carefully chosen group of potential customers.

3.2.3 Determining relative importance of customer requirements

The next step is to evaluate the importance of each of the customers' requirements. This is accomplish by generating a weighting factor for each requirement and fill it in section (ii) in the House of Quality. It is important because the weighting factor indicates how much effort, time and cost need to be invested for each requirement. These weighting factors will be in terms of number from 1 which indicates the most important to highest number of requirement listed in the house of quality which is the least important. In order to give the weighting factor, there are few measures that should be considered.

To whom the requirement is important

How is the measure is important for this diverse group of requirement

3.2.4 Identify and evaluate the competition: How satisfied is the customer now?

The goal of the next step is to determine now the customer perceives the competition's ability to meet each of the requirements. The purpose of evaluating the existing product is to:

Creates awareness that there are currently products in the market that have the same function.

Reveals opportunity to improve on what already exist, or in other word to improve the existing product.

In order to evaluate the characteristic of the existing products based on the data collected from the questionnaires, a scale range between 1 to 5 is developed:

1= the design does not meet the requirement at all

2= the design meets the requirement slightly

3= the design meets the requirement somewhat

4= the design meets the requirement mostly

5= the design fulfills the requirement completely

The scales are used in section (ii) in the house of quality where each of the existing products is evaluated based on the customer requirement. This is the most important part in the design process because from here we could determine whether there is a chance for development if all the scale shows that the existing product highly meets the requirement, than there will be no development needed.

3.2.5 Generate engineering specifications

Once realizing that there are indeed demands from the customer for the better product, the next step is to develop a set of engineering specifications. The engineering specifications are set based on the customer requirements on the section (iii). In this step, we have to find as many engineering parameter as possible. For example customer requirement for adjustable handle can be measured by:

Number of components

Length of components

After all the parameters are determined we can continue by selecting the most appropriate parameter and then we can indicate the level of achievement for each parameter.

3.2.6 Relate customers' requirement to engineering specifications:

Next step is to fill the section (iv) in the House of Quality. Each relationship will be filling with number with number that indicates the relationship between the parameters and requirements. Numbers are going to used representing how strong the relationship is:

9 = strong relationship 3 = medium relationship 1 = weak relationship

0 = no relationship at all

3.2.7 Identify relationship between engineering requirements

In order to determine whether there are engineering specifications that depends on each other, the 'roof in section (v) is added. This is important to realize whether each specification having positive or negative effect on each other. To determine whether there is a relationship between the specifications numbering such as that shown in the previous step can be used.

3.2.8 Set engineering targets

The final step of the QFD is to determine a target value for each engineering measure. These target values are used to evaluate the products ability to satisfy the customer requirements. There are two actions that can be set here on section (vi):

To which extent that the competition meet the customer requirements

To establish the target for new product

In the section (vii) the name of existing product will be filled and on section (vi) will be the achievement of these products for each parameter. For example "number of components", an existing product A has 3 components and goes on. The most bottom of the section will be the target for the new product to complete product A, but depend on the relationship in the center of the table. However few things must be considered here which the best targets are set for specific value. Less precise, but still usable, set within some define range. If target is much different than the values achieve by competitor, the question must be set here is, what we know that the competitor does not know, and do we have the technology and so on.

3.3 Concept Generation

Once the house of quality has been developed, the customer requirement will be used to develop concept generation. "A concept is an idea that is sufficiently developed to evaluate the physical principles that govern its behavior" (Ullman, 1997). In order to avoid poor concepts, customer requirements from QFD method are used during development phase. Some concepts are naturally generated during the engineering requirement development phase.

The flow of conceptual design is shown in figure 3.3.1. Here, as with all problems solving, the generation of concepts is iterative with their evaluation. Also part of the iterative loop is the communication of design information, the updating of the plans, and the decomposition of the problem into sub problems. In line with basic philosophy, the techniques we will look at here for generating design concepts encourage the consideration of the function of the device being designed. These techniques aid in decomposing the problem in a way that affords the greatest opportunity for creative solutions to it.

We will focus on techniques to help with functional decomposition and concept variant generation. These are based on the fact that many important customer requirements are concerned with the functional performance desired in the product. These requirements become the basis of the concept generation techniques. Functional decomposition is designed to further refine the functional requirements; concept variant generation aids in transforming the function concepts.

Develop engineering specification

Generate concepts

Evaluate concepts

Decompose into sub system

Communicate concept information

Product Design

Design Review

Update plans

Terminate

Figure 3.3.1 Conceptual design phase of the design process

3.3 Functional decomposition

Once the target for requirements that had been considered is set, we can proceed to determine the function and decompose them. A proper technique is used to decomposing a problem into smaller, more easily managed parts. It is done by to understanding the functions required of the device and treating each function as a separated subsystem.

Functions tell what the product must do, whereas form or structure conveys how the product will perform. It is a description of a component that includes the flow type, generally valid function, material or information, and specific functions (Andrew Kusiac, 1995). What the customer required is going to be mapped into how the requirements were to be measured. For example, in order to attach any component to another, a person or mechanical assembler must grasp the component, position and attach it in place.

The goal of the functional modeling technique is to decompose the problem in terms of the flow of energy, material and information. This will help better understanding of what product to be are going to perform. Basically there are four steps in applying the technique and it can used with QFD to help understand the problems.

3.4 Generating concepts from functions.

Once the functions of the product are understood, the next goal is to generate concepts to satisfy them. Concepts can be represented as sketches (Figure 3.6), block diagrams, textual descriptions, clay, paper models or other forms that gives some indication of the manner in which the function are achieve with least commitment.

3.5 Sources for concepts ideas

Throughout this stage, the designer teams can take pride in his or her creativity to generate a new idea. This is where a level of creativity will be measured. However, usually one will discover that the idea is not original after all. However it is still a good effort and nevertheless once idea have been generated, at least team member will have an example or proof whether the idea will work as intended.

Useful sources of design information can be searched as a reference. Majority of these sources refer to products that are already embodied and therefore influence the concepts being generated.

3.5.1 Using patent as an idea source

Patent literature is a good source of ideas. It is easy to find on any subject imaginable because there are over five million utility patents that could be search through the internet or local libraries. Furthermore, patent search also helps to avoid from duplicating the existing idea and helps to maintain the originality of the idea generated.

3.5.2 Finding ideas in reference books or journals

Books and journals also can be the best alternative to generate ideas. Most reference books give analytical techniques that are not very useful in the early stages of a design project. However many good ideas are published in trade journals that are oriented towards a specific discipline.

3.5.3 Using existing products and concepts as an idea source.

One of the best sources of idea is to look at existing products. Studying the ideas of others helps us to realize ideas that might have been "missed" by other design team. The functional decomposition done in previous phase helps develop good habits when studying other products. These help team members to come up with an idea to modify concepts from existing products to make it better.

To Design 3D Model via Autodesk Inventor

Introduction of Inventor

Autodesk® Inventor® 3D CAD software offers an easy-to-use set of tools for 3D mechanical design, documentation, and product simulation. Inventor includes an integrated motion simulation and assembly stress analysis environment. Users can input driving loads, friction characteristics, and dynamic components, then run dynamic simulation tests to see how a product will work under real-world conditions. The simulation tools can help users optimize strength and weight, identify high-stress areas, identify and reduce unwanted vibrations, and size motors and actuators to reduce energy consumption. Finite element analysis (FEA) lets users validate component design by testing how parts perform under loads (using actual load information instead of estimates). Inventor’s Parametric Studies and Optimization technology lets users modify design parameters from within the assembly stress environment and compare various design options, then update the 3D model with the optimized parameters. [7]

3.7.2 Building 3D Model

Based on the design concept, a 3D model will be built to get the actual visualize image in 3D based on the specification and design concept that been finalized.

To Build Working Prototype Model

With the guidance post building the 3D model, a working prototype will be built to match the 3D model that meets all the design specification and requirement that have been already analyzed. Then, the prototype to be tested in real life on the functionality if it has fulfilled all the design specification and requirements.

CHAPTER 4 ANALYSIS

4.1 Introduction

In the preceding chapters the importance of the early phase and the chronology of each of the design process are emphasized. The previous chapter also brings to great lengths to understand the design problem and to develop its specifications and requirements using Quality Functional Technique (QFD). However in this chapter the result for each stage of the design process to develop the new product, Electric-powered scrubber will be outline. This chapter will contain the results of QFD method starting from identifying the customer until the final stage which is the 3D model design stage and final working prototype model with the performance measurement test.

4.2 Development of Engineering Specification

4.2.1 Identifying the customers

The class of customer that had been chosen for the development of electric-powered scrubber is the customers who do the cleaning job such as housewife and cleaning personnel. There are several types of cleaning personnel identified depending on their scope of work. They are Wall cleaning personnel, Car cleaning personnel, Equipment cleaning personnel, Toilet cleaning personnel.

4.2.2 Determine customer requirements

Observation and survey method is chosen as an approach to collect data from the customers. In order to build the questionnaires, initial general requirement is listed in order to set targets on the data that is needed. These initial requirements give the initial idea on what are the questions that will be construct order to get the information from the customers.

Table 4.2.1 List of the initial generated requirements that is expected from the

Customers

Functional performance

Flow of energy

Flow of information

Flow of materials

Operational steps

Operational sequence Human factors

Appearance

Force and motion control

Ease of controlling and sensing state

Avoid direct contact with detergent Physical requirements

Available spatial envelope

Physical properties Reliability

Mean time between failures

Safety (hazard assessment) Life cycles concerns

Distribution (shipping)

Maintainability

Life cycle concerns (continued)

Diagnosability

Testability

Reparability

Clean ability

Install ability

Retirement Resource concerns

Time

Cost

Capital

Unit

Equipment

Standards

Environment

Manufacturing requirements

Materials Quantity

Company capabilities

Utilizing the type of customer requirements in Table 4.2, questionnaires are developed (Appendix A). To obtain the data faster, interview had been conducted to 50 selected persons or potential customers who include the housewives and cleaning personnel. As an addition, observation of the customer using existing product is also done.

4.2.3 Questionnaires Analysis

The results of the survey are tabulated in Table 4.2.2. The data is then analysed using graph in figure 4.

Table 4.2.2 Questionnaires analysis

Figure 4.2 Analysis obtained from questionnaires

From the analysis, it is found that majority of the customers are still using the conventional method that is manual cleaning using brush, sponge etc. They are also always performing the scrubbing work in standing position compared to bowing, squatting and others. The general problem that always occur while doing scrubbing work is the chemical effect of detergent on skin, hard to reach area and difficult to remove stubborn stains. Majority of the potential customers also said that handle too short besides too small and heavy brushes.

4.2.4 Determining relative importance of customer requirement

Using initial general requirements as shown in Table 4.2.1 and the result of analysis, customer requirement is further refined and listed down in Table 4.2.3 below.

Functional performance

Keep detergent off users

Fast to prepare

Adjustable handle

Maximum reachable area Human factors

Easy to prepare

Easy to store

Easy to operate

Other factors

Wear resistance

Moderate weight

Affordable price

Electrical powered

Table 4.2.3 List of customer's requirements for the electric-powered scrubber

The key customers' requirements as listed in Table 4.2.3 are then used for the development of comparison diagram in section 4.2.5.

4.2.5 Identifying and evaluating the competition

The competitors are identified by searching the internet to find the existing products that have few similar functions with this product. Furthermore observation on the tools used by the cleaning personnel also helps to determine competitors. As a result, two products have been identified that have the potential to be competitors.

http://img.weiku.com/waterpicture/2011/10/22/16/Floor_Scrubber_634592277761349492_1.jpg http://provi-reiniging.nl/media/catalog/product/cache/1/image/9df78eab33525d08d6e5fb8d27136e95/c/a/caddyclean_classic.jpg

(a) (b)

Figure 4.3 Existing similar products (a) Numetic® system in use in Malaysia and (b) Caddy Clean® manufactured in U.S

Once identified, the competitors' product is evaluated: as shown in Figure 4.3 (a), a product called Numetic® was being used by the cleaning personnel while in Figure 4.3 (b) is an existing product that found through the internet search. The former system is evaluated through observation by looking at how the cleaning personnel handle the machine while the latter product is evaluated based on the technical specification and few information provided by the website. Each competitor's product is compared with customer requirements that have been generated. Each requirement is rated on the scale of 1 to 5 as below.

1= the design does not meet the requirements at all.

2= the design meets the requirements slightly.

3= the design meets the requirements somewhat.

4= the design meets the requirements mostly.

5= the design meets the requirements completely.

From this result, it is clearly that the product (a) which is Numetic® does not meet all the customer requirements. However for Caddy Clean®, there are few requirements that is satisfied but there are still few requirements that is not satisfied. This is in fact an opportunity for further improvement and development of our Electric-powered Scrubber for product requirements.

4.2.6 Quality Functioning Deployments

Once realizing that there is opportunity for the Electric-powered scrubber improvements, a set of engineering specification is developed from the customer requirements. The engineering specification is generated as many as possible that indicates level of achievements for each of the customer requirements. The engineering specification is generated in term of parameters which can be measured. A set off engineering specification for the Electric-powered scrubber is generated and filled up.

Next is to relate the customer requirement and the engineering specification. Numerical value is filled at the centre of the diagram to show the relationship whether it has strong or no relationship at all. The final step is determining the target value for each of the engineering measure. The targets are set for a specific value after studying the competitors. For the advantages than the competitors. It is because the Numetic® machine is an expensive machine while for the Caddy Clean®, the price is increase because shipping and also it can be found in U.K.

Figure 4.4 Quality Function Deployments

4.3 Generating concepts

4.3.1 The overall functions

Once realizing what the customer needed from the previous, the overall function for the Electric-powered scrubber is determined. After brain storming process among design teams, the most important function of the product is to scrub dirty surface using cleaning work in standing position and avoid direct contact with detergent. Further patent search also had been conduct and as a result there are one patent regarding electric power scrubber is found. Several Products’ parts were chosen (example for Handle set from a floor cleaner) to minimise the manufacturing process during prototype construction.

Hand

Handle

Motor/ brush

Verify

Attach

Position

Grasp

Scrubber

Fill with detergent

Detergent container

Figure 4.5 Electric-Powered Scrubber attachment flow

4.4 3D Model and Bill of Material (BOM) of the design

The concepts that had been finalised from previous process are used to create 3D Model. The model will give suffice details to get a clearer visualization of the Electric-Powered Scrubber system. The BOM of the 3D Model are as below Figure 4.6.

Figure 4.6 Bill of Material Engineering of Electric Powered Scrubber

Prototype Model

Based on the 3D model that has been build based on the design specification and requirements, the parts and materials that required to build a working prototype is finalize prior to start building the prototype. Several consideration were made especially on the cost of the Materials/Parts but in the same time the consideration on the deliverability of functionality based on the finalize design concept and specification.

4.5.1 Parts used for rotating mechanism and detergent sprinkler

From the design concept, the rotating mechanism and motor pump is design to be in a box where the rotating floor scrubber attached thru shaft. This means that the weight of the motor should be able to be support by the scrubber motor without loose its rotational tork.

12V DC geared motor (5000rpm of motor speed , 400rpm of shaft speed post gearing)

Figure 4.7 12V DC Motor with Gearing

The reason of selection of this motor is because it is lightweight, with sufficient Tork and cheap compared to other DC motor. The speed of the shaft selected is 400rpm, based on the similar product which is Caddy Clean (US Product) where there motor speed is 420rpm. The size of the motor is small where it is suitable to be installed in a smaller space without consuming space.

12V 2.2 Ah Battery Sealed Lead Acid Battery

Figure 4.8 12V Battery

There is 3 design of 12V battery where it varies based on size and Ampere-Hour which is 17Ah/7Ah/2.2Ah. Ampere-hours (A·h) is the product of the time that a battery can deliver a certain amount of current (in hours) times that current (in amps), for a particular discharge period. This is one indication of the amount of total energy a battery is able to store and deliver at its rated voltage. The reason for selection of this battery is due to the size where is suitable to be installed in the Box together with two DV motor and one water pump. 2.2 Ah is sufficient to support two DC motor and water pump which long lasting for 1 hour upon full charge.

3V Water Pump

http://img.tootoo.com/mytootoo/upload/41/411878/product/411878_3f1a1e3d0e3cb501b7c2a96aaba7144a.jpg

Figure 4.9 3V water pump

3V water pump was selected due to the size which is small and can be compacted in the box together with other parts. The supply from battery will be reduce to 3V by using LM317 IC where it can reduce from input of 12V to output of 3V.

The parts described above are the important parts based on the design specification and requirement which is to rotate the floor scrubber and sprinkle the detergent to floor. The other parts/materials used is as the table 4.5.1

Table 4.5.1 Other parts used to build prototype

Parts

Hand Floor Scrubber

Cover Box

Floor cleaner's handle and head basement

Aluminium Plate

Plastic Bottle

Plastic Tube

Grinder Polish Pad

Aluminium Hollow Pipe for shaft

Electric Switch

Charger Pin

Charger Adapter 12 V

Wire

LM317 IC

M5 Screw

Summary of the total expenditure

Table 4.5.2 Parts / Total cost of expenditure

Parts

Quantity

Cost (RM)

Total (RM)

Hand Floor Scrubber

2

3.00

6.00

Cover Box

1

4.00

4.00

Floor cleaner's handle and head basement

1

30.00

30.00

Aluminium Plate

1

4.00

4.00

Plastic Bottle

1

1.50

1.50

Plastic Tube

1

1.00

1.00

Grinder Polish Pad

2

10.00

20.00

Aluminium Hollow Pipe for shaft

2

0.50

1.00

DC Gear Motor 12V-400rpm

2

25.00

50.00

DC Water Pump 3V

1

15.00

15.00

Electric Switch

4

0.60

2.40

Charger Pin

1

1.00

1.00

Charger Adapter 12 V

1

12.00

12.00

DC battery 12V

1

35.00

35.00

Wire

1

5.00

5.00

LM317 IC

1

3.00

3.00

M5 Screw

25

5.00

125.00

315.90

Table 4.5 shows all the parts used to construct the prototype with the quantity and cost. The total cost/expenditure to construct the prototype is RM 315.90. The cost will reduce by half if the prototype/product is manufactured in company where the more product is being manufacture, the less cost will be for a product which also depends on the demand in marketing.

*Photos of parts and process of constructing prototype in Appendix B

4.5.2 Final Prototype

By using all the parts as describe on table 4.5, the prototype is then constructed step by step by taking a safety precaution during the execution by using a proper attire and tools. Below is the picture of completed Electric Powered Scrubber prototype.

Figure 4.7 Electric Powered Scrubber working Prototype

Operating Principle

Figure 4.8 Main Box

Charger Port

LED

Switch to select option to operate with battery power or directly from adapter

Switch to charge the battery when plug to adapter

Figure 4.9 Hand Switch

Switch to turn on detergent pump

Switch to turn on scrubber

Performance Measurement Test

Upon completion of the prototype, it’s time to test the functionality by utilizing the prototype to scrub toilet floor and to test if all the design specification as finalized in QFD can be achieved.

Electric Powered Scrubber Performance Test Mark Sheet

Keep detergent off users

10

Fast to prepare

9

Adjustable handle

10

Max. reachable surface

6

Easy to prepare

7

Easy to store

7

Easy to operate

8

Wear resistance

0

Moderate weight

9

Affordable price

7

Reduce cleaning time

8

Ergonomic

9

90

Handle floor Brush Performance Test Mark Sheet

Keep detergent off users

0

Fast to prepare

10

Adjustable handle

0

Max. reachable surface

7

Easy to prepare

10

Easy to store

10

Easy to operate

10

Wear resistance

0

Moderate weight

10

Affordable price

10

Reduce cleaning time

5

Ergonomic

2

74

Based on the comparison between both methods, Electric Powered Scrubber gained the highest mark which is 90 marks compared to 74 marks by Handle Floor Brush. It is obviously shows that the design is favourable and fulfils the customers’ requirement and needs.

Figure 5.0 Electric Powered Scrubber

Figure 5.1 Handle Floor Brush

CHAPTER 6 CONCLUSION AND RECOMMENDATION

6.1 Conclusion

Upon the completion of this project, the following have been achieved:-

QFD has been prepared from customer requirement to get the general concept.

An efficient, safe and user friendly electric powered scrubber has been developed using the engineering design process.

A 3D and physical model has been developed in order to visualize the product to facilitate design improvement.

A working Prototype has been constructed with the test conducted to test the functionality if it is as per the design specification and requirement.

6.2 Future Recommendation

To concentrate on the joint of handle and head box where the current design is flexible movement to give full control to the customer during the scrubbing process but it just restricted to floor. It would be recommended if customer can have option to tighten the movement so that the scrubber can be utilize to clean walls in the same time.

Electric Powered Scrubber with variable motor speed where A further analysis on types of motor to be used base on the requirement. The benefits are the scrubber can be used either for scrubbing (medium speed) and polishing (high speed).