Functional Decomposition of Biological Systems

Content adapted from:Nagel, J.K.S., Nagel, R.L., Stone, R.B. & Mcadams, D.A., 2010. Function-based, biologically inspired concept generation. Artificial Intelligence for Engineering Design, Analysis and Manufacturing, 24, 521-535.

Today’s Journey

• DANE/Ask Nature facilitate searches for biological analogies

• Functional Modeling provides means to explore a problem while maintaining solution independence

• Today we talk about a larger process– Creating functional models of biological phenomena– Customer-Driven Bio-Inspired Design Process– Biology-Driven Bio-Inspired Design Process

Bio-Inspired Concept Generation Approaches

Last Lecture DANE/Ask Nature/Others

Biological System Functional Decomposition Process

1. Identify a suitable reference source for the system of interest (biology text book, etc.)

2. Learn about the biological system– Be the biologist– Use biological thesaurus to relate flows between

engineering systems and biology

3. Define the question– What is the functional model trying to answer?– This is a problem statement

4. Define the mimicry category

Biological System Functional Decomposition Process

5. Choose an organization level– Create the blackbox model– Read and investigate literature at this step

6. Develop functional model– Use thesaurus to translate functions– Biologists and engineers talk differently

7. Validate functional model

Engineering-to-Biology Thesaurus

• Most engineers are not biology domain experts

• Can lead to difficulty understanding biology descriptions

Mimicry Categories

• Physiology: the vital functions and activities of organisms, as opposed to their structure; the way in which a living organism or bodily part functions

• Morphology: the form and structure of an organism, and the associations among the structures of an organism

• Behavior: the sum of the responses of an organism to internal or external stimuli

• Strategy: generic behavior that is exhibited among multiple biological ranks to achieve different goals

Levels of Organization

• Biological systems contain many levels of organization– Organism, organ, tissue, cell, etc.

• Functional models at different levels of organization can provide different insights and inspiration– Where do you want to “focus” for inspiration?

Exercise

• What different levels of organization might be of interest in a shark and what might you expect to gain insight into for each?

• Consider each of the following levels: – atomic, molecular, molecular complexes, subcellular,

cellular, multicell systems, tissue, organ, multiorgan systems, organism, population, and behavior

10 minutes

Exercise

• What different levels of organization might be of interest in a shark and what might you expect to gain insight into for each?

• Here are some levels and insights:– Organism – Aerodynamics, energy

distribution/efficiency, motion in water, etc.– Organ – Gas exchange (gills), pumping (heart), etc.– Tissue – Low friction surface (skin)– Cell – Small scale motion, small scale assembly, etc.

Levels of Organization

• Since for any one organism or biological system there are many different levels of organization, each providing different insights, many different functional models are possible

• Choose the level that fits the application best

Case Study: Armadillo• Function of interest:

Defense (Stop Solid)• Level of Organization:

Organism• Note: Only flows and

functions relevant to the overall function of interest need to be included in the model

Case Study: Armadillo

Biological Functional Model

Exercise

• Come up with a functional model of the puffer fish defensive mechanism (swallowing water to make itself look bigger)

15 minutes

Exercise

• Come up with a functional model of the puffer fish defensive mechanism (swallowing water to make itself look bigger)

Biological Decomposition Uses

• Simplifying and translating biological system– Functional decomposition allows the abstraction

of a biological system with an interesting function– Once in functional form, the system can then be

relatively easily converted into an engineering system design

Biological Decomposition Uses

• Building a design repository database– Decomposing many biological systems and storing

the results in a searchable database allows for engineers to find biological inspiration for specific functions

– The OSU Design Engineering Lab Design Repository that includes both biological and mechanical systems

Design Repository

• OSU Design Repository– http://repository.designengineeringlab.org:8080/v

iew/browse.jsp