DEDAN KIMATHI UNIVERSITY OF TECHNOLOGY
DEPARTMENT OF MECHATRONICS ENGINEERING
YEAR THREE FIRST SEMESTER
DESIGN REPORT: FOOD SCIENCE GROUP.
PROJECT: AUTOMATED COFFEE BEAN PROCESSING MACHINE.
GROUP MEMBERS
NAMES REG NO SIGN
MIKE ARASA E022-1322/2012
JORUM AYUB E022-0940/2012
ARTHUR NGUGI E022-1277/2012
MELVIS WANJIRU E022-1272/2012
CYRUS WAIRIMU E022-0967/2012
FAITH CHEPNGETICH E022-0930/2012
SOLOMON WANGAI E022-0130/2012
JUMA BAKARI E022-1153/2012
RAMADHAN KAZUNGU E022-0966/2012
JOSEPH WANYEKI E022-0128/2012
Abstract (or executive summary)
The objective of our project was to successfully redesign a new coffee maker that is cheap and affordable .Generally our team was to come up with a coffee maker that is easy to use, detachable, user friendly and automated. The goal our team accomplished was to design a coffee maker that is automated, a maker bigger than its original design, and still be detachable. Our design process began with the task of analyzing the current market and customer needs. Also, through external research, we generated ideas. Concept generation/selection narrowed our findings down to one superior maker
Introduction
. The original roaster was made out of grey cast iron (it can also come in black). It major advantage is that it is durable and has a system that removes chaff and cools the beans. For the most part, it received a fairly low rating, within a two to five star range out of five. Our team was asked to redesign the existing coffee roaster from Probat Company in Germany. However, the operator found several problems with the coffee roaster. Therefore, we aimed to correct those problems while also creating a new roaster suitable for our target customers.
Our redesign altered the appearance of the former coffee roaster. We did this externally, by incorporating an adjustable rotating drum with two of its ends adjustable hence creating space for higher capacity rather than the fixed drum on the original roaster which had a small capacity for the beans. We also assimilated a grinder in the roaster as a part of the machine as opposed to a separate grinder as in the original roaster. In the measurement and instrumentation aspect for temperature regulation, we decided to include a resistance temperature detector which is used as a temperature measuring device by passing a low current through it and measuring the voltage drop. The more the temperature rises the more the resistances build up and are hence translated to degrees. First, we completed product research. Next, customer needs were analyzed and target specifications were determined. After, a concept generation morphological chart was used to develop ideas, and then limit them to the several best options for redesign. Lastly, one concept was selected via the use of a concept selection matrix. This specified design process is one which our team followed to a tee to bring forth the best possible option for redesign. It further proves that this is the best redesign selection through calculations and obtained evidence.
Mission Statement
Our goal with this project was to efficiently and effectively redesign a coffee maker that is automated and easy to fabricate. Through research, generation of ideas, and keeping given design restrictions in mind, our team developed a coffee roaster that has a 2 in one consideration i.e. a roaster and a grinder connected together. The roaster is also detachable and easy to fabricate.
Problem Statement
The problem given for our team to resolve was to redesign the coffee maker that is available at the coffee lab. We then needed to redesign this coffee maker to meet the
needs of the everyday of the users in the coffee lab. However, our team was asked to keep
several constraints in mind. These constraints included: to have the coffee maker be as
automated as possible, able to perform two processes in one machine ,process more coffee beans than the original one and should be detachable for easy maintenance .
5.0 Product Research
In the lab, we as a team did external research by interviewing the coffee lab technician, observations, by the use of questionnaire and also doing research in the internet. After obtaining this external research, we documented our findings in a lab report, compiling our data.
Customer Needs Analysis
CUSTOMER STATEMENT AND INTERPRATED NEEDS.
CUSTOMER: MR KINUTHIA INTERVIEWERS : GROUP FOOD SCIENCE
ADDRESS:657- NYERI DATE : 22-5-2014
TELEPHONE: 0726361951
CURRENTLY USES:PROBAT ROASTER
WILLING TO DO FOLLOWING UP? YES TYPE OF USER :SMALL SCALE
QUESTION/PROMPT
CUSTOMER STATEMENT
INTERPRATED NEED
TYPICAL USES
I need a machine that does not quality by producing soot.
Proposed roaster should be environmentally friendly and avoid soot.
I need to see the heating action in the roaster.
The proposed roaster is to have such a consideration.
LIKES OF THE CURRENT COMPONENT.
I like the material used to make the component, since its durable and does not react with coffee beans
Quality of the coffee ought to be good thus no reaction with the chief material of component.
I like the cooling mechanism and the sucking-blowing mechanism which eliminates chaff.
Roasting process is efficient and clean i.e. removes chaff. Also cooling is vital to the process.
DISLIKES OF THE CURRENT COMPONENT
The user is fully involved in the roasting process.
An automation consideration is to be put into place.
Maintenance of the machine is expensive.
Develop a proposed roaster whose maintenance is to be affordable to the customer.
The machine is too heavy thus it has limited portability options.
Portability options are to be provided for in line with the need.
Gas is the current energy source which is expensive and not durable.
Come up with a machine that uses an energy source which ensures an affordable process
SUGGESTED IMPROVEMNTS.
Would be nice if the machine could perform some processes at ago i.e. a 2 in 1 machine.
The proposed machine is to have a 2 in 1 accommodation.
Prefers an automated system whereby operator involvement is reasonable.
Automation provision is to be provided for.
Would be nice if the capacity is increased.
Machine capacity is to be increased in accordance to the design.
Prefers a component which can be assembled and detached easily. {for cleaning purposes}
Component to be made is to focus on the easily assembly and detachment specification.
Target Specification
The targets that we selected from our research were capacity of the drum of the coffee roaster, design of the drum , maintenance ease, combination of the grinder and the roaster, ease of use and cost. These targets were complimentary with the customer importance needs we assessed above. We gave the coffee machine that we started with a rating of 3 out of 5 for each target. The ideal target specification would be the best that our team could hope for. The marginal is the minimal value we can produce with the customer still buying. The features of the capacity of the roaster, design of the drum, combination of grinder and roaster, cost, and how much it makes have specific numerical values, not ratings.
Concept Generation
We now used a morphological chart to generate concepts. We used the 6 major principle parts of the coffee roaster that we thought were the most important. We brainstormed and thought of different ways in which each could be used
ENERGY
SOURCE
TEMP.
REGULATION
MECHANISM
DRUM
PLACEMENT OF HOT COFFEE BEANS
MECHANISM OF RECEIVING HOT BEANS
GRINDING MECHANISM
AND RECEIVING TO COLLECTOR
gas
Bimetallic strip
Adjustable
Perforated plate with pressure sensors
Hydraulic system
Funnel shaped with rotating blades
electricity
Thermocouple
Semi hot blast cylinder
Tilting system
Grinder with sieve
Hybrid
(ELECTRO GAS)
RTD( resistance temperature detector)
Semi hot blast dual cylinder
Funnel to collector with an alarm that signals the process is over hence collection
Digital temperature sensor
Infrared coated cylinder
Piping system
spherical
Morphological chart
With these functions we came up with 4 concepts.
Concept 1
Gas
Bimetallic
Semi-hot blast cylinder
Perforated plate with pressure sensor
Hydraulic
grinder with sieve
concept 2
hybrid( electro-gas )
RTD
Adjustable drum
perforated plate with pressure sensor
tilting system
funnel shaped with rotating blades
grinder with sieve
funnel to collector with an alarm that signals the process is over hence collection
concept 3
electricity
thermocouple
infrared coated cylinder
perforated plate with pressure sensor
tilting system
piping system
concept 4
hybrid (electro-gas)
bimetallic strip
spherical drum
perforated plate with pressure sensor
hydraulic system
funnel shaped with rotating blades
Concept Selection
We used a concept screening matrix to narrow down the number of concepts that we wish to continue with .We used the same six principle parts that we used previously. We used a + if it was better than the model, a 0 if it was the same and a – if it was worse. After adding these up and finding the net number, we were able to rank our concepts. We used the best concept to select our final design.
CONCEPT 1
CONCEPT 2
CONCEPT 3
CONCEPT 4
TEMP.
REGULATION
MECHANISM
0
+
+
+
DRUM
-
+
-
-
PLACEMENT OF HOT COFFEE BEANS
+
+
+
+
MECHANISM OF RECEIVING HOT BEANS
-
+
+
-
HEATING MECHANISM
0
+
0
+
GRINDING MECHANISM AND RECEIVING OF GROUND BEANS
0
+
-
+
SUM +
SUM-
SUM 0
1
2
3
6
0
0
3
2
1
4
2
0
NET SCORE RANK CONTINUE?
-1
4
NO
6
1
YES
1
3
NO
2
2
NO
We therefore selected concept 2 as the final design.
Conclusions
Following a long process which included research, concept generation, and several
other steps, we arrived at our final decision. The final decision was made based on the fact that it fit the criteria of what we felt would be a popular coffee machine in the
Kenyan market. We went through many stages to finally come to a decision about which coffee machine would be the best fit. The process began with us analyzing a popular coffee
Machine from Probat Company based in Germany. We identified its pros and cons and moved onto the research portion. We researched many topics including popular coffee machines currently in the Kenyan market. We also looked up alternative heating methods ,drum capacity and designs. After researching and finding our customer needs it was time to generate concepts. We developed several new ideas for coffee machines. A weeding process then took place with each concept being graded in comparison to the original. After slowly cutting down the number of concepts we came up with our final design.
The final design is an attempt to make a coffee machine that is easy to use ,cost effective ,easy to maintain and can combine both the grinding and roasting processes in one machine. This modern design will both affordable to most users and generate positive results. This item has been well thought out and has potential to be a popular coffee machine in the Kenyan market.
References
References
Books
Keep.Ulrich and South.Eppinger;Product design and development,Irwin/McGraw-Hill,2000
Clive L.Dym ,Patrick Little and Elizabeth I.Orwin;2014;Engineering Design ;A Product Based Approach ;4th Edition ;John Wiley and Som Inc Publishers.
Mr.Inno Odira;Lecture Notes ;2014
Websites
Coffee Grinders PT.2:5 Things to consider when you buy a grinder;2014;retrieved;26/07/2014;from www.coffeekind.htm
Automatic Controlled Roasting System ;2014;retrieved on 26/7/2014;from www.turkey.htm
Grinder burr types explained ;2014;Retrieved on 25/7/2014;from www.barista.com
ProbeGuide:A Roasters Perspective ;Jan 22,2014;Retrieved on 20/07/2014;from www.cropster.com
Intelligent Roasters ;2014;Retrieved on 20/07/2014 from www.geniointelligentroasters.com