The lesson outcomes are to explain how to recognize a need, identify the components in the problem definition, discuss the design considerations, and develop a problem definition statement related to agriculture.
8th International Conference on Soft Computing, Mathematics and Control (SMC ...
recognize a need & problem definition
1. RECOGNIZE A NEED & PROBLEM DEFINITION
Design Philosophy
Dr. (Ms.) Jayaruwani Fernando, Ph.D. (Ag. & Biosystems Engineering), M.S. (Industrial & Ag.
Technology), M.Phil. (Ag. & Biosystems Engineering), B.Sc. (Agriculture)
2. LESSON OUTCOMES
• Explain how to recognize a need
• Identify the components in the problem definition
• Discuss the design considerations
• Develop a problem definition statement related to agriculture
Dr. (Ms.) Jayaruwani Fernando, Ph.D. (Ag. & Biosystems Engineering), M.S. (Industrial and Ag. Technology), M.Phil. (Ag. & Biosystems Engineering), B.Sc. (Agriculture)
3. STEPS OF THE DESIGN PROCESS
1. RECOGNIZE THE NEED
• The first step is to establish the ultimate purpose of the project.
• Often, this is in the form of a general statement of the client’s dissatisfaction with a
current situation.
Ex. – “The chili produce from the hammer mill is not properly pulverized.”
• This is a general statement that does not comment on the design approach to the
problem.
• It does not say that the major components in the hammer mill need to be modified.
Dr. (Ms.) Jayaruwani Fernando, Ph.D. (Ag. & Biosystems Engineering), M.S. (Industrial and Ag. Technology), M.Phil. (Ag. & Biosystems Engineering), B.Sc. (Agriculture)
5. RECOGNIZE THE NEED
• Recognition and phrasing of the need are often very creative acts because
the need may only be a sensing that something is not right. For this
reason, sensitive people are generally more creative.
Example:
1. The particle size distribution is not in the acceptable range for ground chili
2. The need to do something about a food packaging machine may be
indicated by the noise level, variation in package weights, or by slight but
visible variations in the quality of the packaging
Dr. (Ms.) Jayaruwani Fernando, Ph.D. (Ag. & Biosystems Engineering), M.S. (Industrial and Ag. Technology), M.Phil. (Ag. & Biosystems Engineering), B.Sc. (Agriculture)
6. 2. PROBLEM DEFINITION
• This is one of the most critical steps of the design process.
• There is an iteration between the definition of the problem and the
recognition of need.
Recognize the need
Problem definition
Dr. (Ms.) Jayaruwani Fernando, Ph.D. (Ag. & Biosystems Engineering), M.S. (Industrial and Ag. Technology), M.Phil. (Ag. & Biosystems Engineering), B.Sc. (Agriculture)
7. PROBLEM DEFINITION
• The problem definition is more specific than recognizing the need.
• For instance, if the chili is not properly ground by the hammer mills, the need
may change in feeder design or hammer design.
• Feeder design modifications – change the operational speed of the feeder
to maintain optimum amperage loading to the main motor
• Hammer design modifications – change the rotor speed, motor
horsepower, and hammer design (end of rod)
• Optimal hammer design and placement will provide maximum contact
with the feed ingredient.
Dr. (Ms.) Jayaruwani Fernando, Ph.D. (Ag. & Biosystems Engineering), M.S. (Industrial and Ag. Technology), M.Phil. (Ag. & Biosystems Engineering), B.Sc. (Agriculture)
8. • Often the true problem is not what it first seems.
Eg: Problem – “The chili produce from the hammer mill is not properly
pulverized.”
Not a problem with hammer mill, the problem is with moisture content
of chili
PROBLEM DEFINITION
Dr. (Ms.) Jayaruwani Fernando, Ph.D. (Ag. & Biosystems Engineering), M.S. (Industrial and Ag. Technology), M.Phil. (Ag. & Biosystems Engineering), B.Sc. (Agriculture)
9. PROBLEM DEFINITION
• The problem definition must include all the specifications for the thing that is to be
designed.
• Anything which limits the designer’s freedom of choice is a specification.
• It is important to write a formal problem statement which expresses what the design
is to accomplish
Include: * Objectives and goals (musts, must nots; wants, don't wants)
* Constraints
* Criteria used to evaluate the design
Dr. (Ms.) Jayaruwani Fernando, Ph.D. (Ag. & Biosystems Engineering), M.S. (Industrial and Ag. Technology), M.Phil. (Ag. & Biosystems Engineering), B.Sc. (Agriculture)
10. PROBLEM DEFINITION
Example:
• Design a continuous infrared final dyer to reduce the moisture content of chili
before feeding chili to the hammer mill.
• The dryer must be able to;
1. reduce the moisture content of chili up to 7% (wb)
2. produce a product throughput of 350 kg/h
3. continuously dry chili using a belt which has an optimum length of 7.5 m
Dr. (Ms.) Jayaruwani Fernando, Ph.D. (Ag. & Biosystems Engineering), M.S. (Industrial and Ag. Technology), M.Phil. (Ag. & Biosystems Engineering), B.Sc. (Agriculture)
