1.1a Anthropometrics
Essential idea
Designers consider three human factors to ensure products meet ergonomic needs.
Nature and Aims of Design
Nature of design:
Design is human centered and, therefore, designers need to ensure that the products they design are the right size for the user and therefore comfortable to use. Designers have access to data and drawings, which state measurements of human beings of all ages and sizes. Designers need to consider how users will interact with the product or service. Use and misuse is an important consideration.
Aims of Design: (1.5, 1.18, 1.20)
Aims:
Aim 6: Anthropometric data sets can vary significantly between populations. Particularly in the fashion industry, the variance in these data sets impacts the size range of clothes for particular markets.
Guidance
As DP Design student, you will need to:
Collect anthropometric data and consider its reliability and limitations
Understand the difference between dynamic and static measurements; recognize design contexts where these types of data would be used
outline how Anthropometric data can differ between populations
explain and compare the terms "range of sizes" and "Adjustability", and identify relevant design contexts
understand and outline the disadvantage of designing for the "average" (50th percentile).
Interpret percentile tables for user populations
recognize the 5th, 50th, and 95th percentiles of a data set
Recognize Design contexts where different percentile ranges are used
outline the advantages and disadvantages of using data from just the 5th and 95th percentile
Describe the difference between Anthropometrics and Ergonomics
Summmary
Human psychology is complex and difficult to classify into groups for designers
Designers must analyze the human information processing system to identify potential breakdowns and their effects
Designers use various methods to collect psychological data, and understanding the type of scale used and whether the data is qualitative or quantitative helps interpret its significance and application in the design context.
As you watch the video, consider the following questions:
What are the challenges designers face when trying to classify human beings into groups?
What are the different types of scales used to collect psychological data, and how do they differ from one another?
Why is it important for designers to understand how the human information processing system works and how it can break down?
What is ergonomics?
Discussion and analysis
11:21-14:05 Scenario 1: non-adjustable designs
Watch this section and discuss some of the key ideas or understandings that the presenter raises.
Based on the video, what are 3 ideas about ergonomics that designers should consider?
Concept and principles
Ergonomic Data and Measurements
Anthropometric data consists of measurements of the human body--height, weight, arm length, etc. Datasets of anthropometric measurements can come in various forms, populations groups, quality, and sample size . Therefore, the designer should use a data set that is best suited to their design goals.
Primary data is data about the specific target audience that is gathered first hand by designer. This data can also be considered survey data and tends to consist of a relatively small numbers of samples.
Secondary data typically comes from data sets that are produced by government agencies or research groups and have a relatively large sample size.
Anthropometric data can consists of two types of measurements: Static and Dynamic
Static Measurements: measurements of length between points on a body.
Dynamic Measurements: measurements of reach, movement, or strength. These measurement would be used to determine how a person moves in a space (i.e. reaching for a lever from a seated position, turning a wheelchair around, etc.) or how much force is required to complete an action (i.e. opening a lid, turning a wheel, etc.).
Dynamic measurements (on the left) compared to static measurements (on the right)
Reach
Regarding reach, measurements are often differentiated as either normal reach or maximal reach. Normal reach would indicate a the distance a user could comfortably extend their arm, while maximal reach indicates the maximum distance they could extend their arm.
The implication is that normal reach would indicate a distance where objects or controls are comfortable and easy to reach with minimal physical stress, and where they can be accessed easily and repeatedly; maximal reach, on the other hand, would be accessible, but would require some effort and not be ideal for repetitive or frequent actions.
Percentiles and Percentile Ranges
When designing a product or service, designers need to determine which Percentiles their product will serve. From this, they can determine specifications such as the physical size or fit, or how much force is required to operate a button.
As each human has distinct physical and mobility characteristics, simply averaging the data collected will not ensure that accessibility or comfort for users. Through collecting primary and secondary data, designers can determine which range of users they need to design for.
See here for a detailed description of interpreting percentiles for designers.
What is a percentile? A percentile is used in statistics to show the value below which a certain percentage of a group falls. The 25th percentile is the value at which 25% of the population are at or below.
The 50th percentile is the point at which people half the people in the group (The mean) would be 130cm tall or less would be accommodated. Likewise, if the designer had used just the 5th percentile as their reference, then only those 115cm or shorter would be accommodated.This is where designers must carefully consider who they are designing for and what measurements are important. The design context is important. Consider the 50 percentile (130cm). Even though it is the mean of the user population, it does not include anyone who is above this average.
Application of Percentiles in Design
Consider these different design contexts and how height would play an important role in the design considerations:
An opening for an elevator:
The height of a shelf on a wall
Height of a safety railing
The location and height of an elevator button
In each of these situations, the designer would need to identify which percentile would provide them with the data to meet the design goal. Do they need to consider the tallest or the shortest user in their design context?
FACTORS THAT INFLUENCE ANTHROPOMETRIC MEASUREMENTS
Factors such as Age, Gender, Ethnicity can influence these measurements. For these reasons, designers must carefully consider the source of their data sets and whether they are applicable to the design context.
USING ANTHROPOMETRIC MEASUREMENTS
Follow these steps for identifying the data and percentile ranges you will use (adapted from here).
Decide who you are designing for: Identify the user population (adults, men, women, children, etc.)
Decide which measurements are relevant: Identify the static and dynamic measurements that will be necessary for you to consider in your design (height, reach, grip strength, etc.)
Decide what percentile you need to design for: Will you design for the average user (the 50th percentile), or for the extremes (the 5th or 95th percentiles)? Depending on your design and user population, you need to select the relevant data to guide your design specifications.
Sources and Databases of Anthropometric Data
Size Korea: Korea Datasets
Human Scale: Calculator
WHO Growth Reference Data: World Health Organization data of growth rates for children 5-19 years old
List of Data Sources: Collected by Tufts University; wide variety of sources
DP DESIGN CURRICULUM NOTES
International-mindedness:
A wide selection of anthropometric data is published and regionalized, for example, Asian data versus western European data. The designer must work with data appropriate to the target market.
Theory of knowledge:
Do the methods of data collection used in design technology have more in common with disciplines in the human sciences or the natural sciences?
Utilization:
Design technology Topic 7
Aims:
Aim 6: Anthropometric data sets can vary significantly between populations. Particularly in the fashion industry, the variance in these data sets impacts the size range of clothes for particular markets.
Resources
Openerg.com has lots of information about calculating, measuring, and apply ergonomics
ergonomics4schools.com has detailed explanations and descriptions for how ergonomics can be applied
Penn State Open Design Lab: Online links to data, calculators, models, and guidelines
NASA: Anthropomorphics and Biometrics: Information about human body size, posture, movement, surface area, volume, and mass
Allsteel: Ergonomic Principles in Design: PDF outlining principles and concepts of ergonomic design and how it is applied to office seating
Human Ergonomics: Website of an ergonomic consulting firm with detailed resources on a range of issues and principles related to ergonomics and design. Many links to databases, health and safety information, and standards.
Research
The Quarterly of Human Factors and Design: An online journal and blog about issues related to human factors and ergonomics
Herman Miller: Innovations in supported seating: PDF or HTLM: White paper outlining the benefits of ergonomic seating in the workplace
Herman Miller: The Eyes Always Win: PDF or HTML: White paper outlining the heath implications of poor monitor placement in the workplace