Production I- Production I-
Chapter 3 Part A
3.2. Concept Genesis
3.2.1. Problem I~ecognition
3.2. J. J. Attribute Listing
The attributes of;) design are those qualities and or quantities that distinguishes the product from others. By identifying these attributes the designer will empower himself with the ability to focus on a particular aspect of the product. Having stated that, the attribute listing method can be most appropriately diagnosed for projects cOllcemed with product enhancement where the basic concept of the product has already been established and the enhancement is required to eliminate defects or the optimization with respect to product economics, functional operation, material expenditure or clari ficatiol1 and expansion of market potential.
It is quite possible and sometimes an absolute necessity for repetition of the attribute listing procedure until the fundamental features which characterize every feature of the product are known. By doing this the product may be dichotolllized into more comprehensible aspects. The attribute listing method forces the designer to expand his horizons and thereby stimulate the creation of alternative ideas.
3.2.1.2. Input - Output Analysis
This technique attempts to erect a bridge to link the system input to the system output with the freedom to chose the means by which the input may be transfonned into the output. In other words there is no prepossessed solution to the problem.
As a technique it is was originally fonnalized for the design and development of products which perfonn as physical task or function. As mentioned above, the method embraces three abstract aspects of a product viz. input (in going power or
force), Olllput (corresponding action or force), .~pecificatioll (addition information that may govern the nature of the input and output).
The input-output analysis method has been developed considerably slllce its conception. The philosophy behind the refined technique is that structure follows function. At this point, it is important to understand what the term function means in a design context and to differentiate it from the form of the design. FlInction communicates what the product should do and not how it is to be done. The /01'111 of a product will be a disclosure of how it will be designed to fulfill what it must do
For a complete understanding of the technique it must be understood that function can also be described as the logical tlow of energy, material and or information.
Those functions associated with energy flow can be described by both energy type and by the effect that it has on the system. Energy flowing though a system may be stored, transformed, conducted, supplied and dissipated. With this in mind the words used to describe the flow of energy are verbs.
The flow of material may be best described by defining its subdivisions. Through flow is a material conserving process, divergillgflow can be described as dividing the material into two or more components, converging flow is an assembly or joining of materials. The functions associated with information flow can embody
mechanical, electrical and or fluid signals.
As a technique the input output analysis can be used for the genesIs of new concepts and the enhancement of existing ones. To give direction to the utilization of this technique the four steps listed below need to be followed.
Step J : Find the overall fimclioll that need\' 10 be accomplished Be aware of the system boundaries
Slep 2 :
Slep 3 :
Slep 4 :
Remember that energy and materials are conserved All objects that interface with the system must be listed The information nows may be included in the diagram by asking the question : How will one know if the system is perfomling?
Creale sub jUllction descriptions
consider what and not how!
break down the function as finely as possible consider the operational sequence
list alternative functions
include the function box or function table; the action word
(verb); the object on which the verb acts; the known material, energy and information.
Order the sub fimcrioll
the now should follow a logical or temporal order
redundant functions should be identified and eliminated or combined.
Refine Sub fUllctiolls
decipher whethe.r the functions listed above are truly basic functions i.e. in their simplest fonn
make sure that all assumptions regarding the product are documented and properly voiced.
make sure that the function is directed at what and not how unless the how was assumed at the onset ensure that the domain of knowledge required of the product is sufficient.
3.2.1.3. Morphological Analysis
This technique entails firstly the listing of the all the parameters involving what the product should do, in other words the listing of the device functions, and secondly the listing of ways and means of fulfilling these required functions. It is important that these said ways and means arc of the same level of abstraction as different levels would place this technique under different sub-catergorics according to which concepts are generated. For example. if the task at hand was to lift an object from point A to point B, then if one offered potential solutions as being fluid power, electrical power, or possibly using a mechanical advantage these items would be on the same level of abstraction falling under the sub-catcrgory of problem recognition. A hydraulic motor, a hoist or mechanical linkages would be a list of the same abstraction level and would fall under the category of idea simulation. The author has found that in practice a listing similar to the latter of the two is a simpler means ofvisuaJizing the final device, provided that a valid general and functional abstraction has been carried out.
The morphological chart is presented as a tabular matrix vertically listing the required functions on the extreme left and each one in tUnl followed by a horizontal listing of the possibilities available in conceptual fulfillment of the product. It follows sequentially from the effort invested in the input output technique, however takes it to the next level by considering the methods available to achieve the required function. A morphological analysis will prompt the mind into considering the total problem at one time.
The value of this technique lies in the fact that numerous solutions to the problems become immediately available with the number of solutions limited only by the number of alternatives available in fulfillment of the function. The draw back of the technique is oddly enough the same as its advantage. The generation of too
many solutions might in fact be bewildering. It takes good engineering insight to decipher the practicality of a possible solution. The designer should ask himself whether or not the combination as put forward can gel together as a working unit.
He should also be aware of the implications of gelling such sub systems.