Device for modeling sitting posture.
Finding the correct user silhouette is a fundamental concern in the design process of
seating furniture. The primary objective of this project was to design and develop a
device that allows students to experiment with various seating positions before
finalizing their design projects. This device facilitates educators in conducting
ergonomic seating workshops with students and also aids in gathering insights into
ergonomic challenges in chair design, which can be shared with students.
The development of a seating furniture prototype is a time-consuming and
resource-intensive endeavor. The device serves as a bridge between CAD systems,
ergonomic data, and a physical model on which users can sit and assess seating
comfort. With this device, students and designers can make more informed decisions,
streamlining the design process and making it more productive.
The project was carried out in two stages. Initially, a basic version of the device was
constructed and tested in collaboration with students and during the design of two
commercially-oriented furniture collections. Building on the feedback and lessons
learned from the first prototype, a refined version of the device was designed.
There is an anecdotal opinion that says sitting is like smoking cigarettes – there is no
form of it that would be healthy for humans. However, it’s hard to imagine the
functioning of a modern human (at least in areas influenced by Western culture)
without sitting in chairs. We work, rest, and most often eat while sitting, so it’s very
important to design furniture that will harm us as little as possible and serve us as well
Despite many innovations and the growing popularity of remote work, sitting still
occupies a large part of our lives. Unfortunately, knowledge in this area among
designers and manufacturers often proves to be insufficient. This is because it is not a
widely popular and easily accessible knowledge. It is not widely developed and
expanded upon. Knowledge about the ergonomics of sitting is often based on
superficial experiences or patterns that we fall into and repeat.
The aim of my project is to improve the seating design process, both during furniture
design courses in academic centers and in commercial enterprises that design and
manufacture seating furniture.
As a student and young designer, I always felt uncertainty and dissatisfaction when
looking at ergonomic tables and diagrams according to which we designed seating
furniture. These guidelines and hints were completely abstract values for me, which I
couldn’t translate into real furniture.
When I started working on my first independent commercial project, for which I was
fully responsible, such an approach seemed insufficient. At the same time, I was
already working as an assistant in the Interior Architecture Department at Dr. Michał
Kapczyński’s Furniture Design Studio. While working with students, I saw the need to
create a tool that would allow testing the comfort of the seat before it is made. This
was the first impulse to create a prototype of the system developed as part of this
The inspiration for taking up the thesis topic is the observation of the design process
that students go through during the Furniture Design Studio course of Dr. Michał
Kapczyński, where I serve as an assistant. During our course in master’s studies,
students have to deal with some kind of seating furniture, depending on the task we
are working on in a given year. Depending on the assignment, these can be furniture for
relaxation, work, cafes, etc. Seating furniture is an important and very popular task in
the training of young designers in disciplines related to interior architecture and
Another source of inspiration and observation of problems related to seating furniture
design are my own experiences as a designer. While conducting a studio focused on
making design projects, I have had the opportunity to design seating furniture several
times. The process of creating commercial designs, which are produced on a large
scale, is different from academic considerations and constitutes an important
experience that has helped me in designing the device.
In today’s world, the design process has been dominated by CAD systems, which
greatly accelerate the work of designers. Despite their undeniable advantages, CAD
systems also have a fundamental disadvantage – they disconnect the designer from the
material world. Often, prototypes made based on the CAD model turn out to be
completely different in perception than they looked on the computer screen. Design –
whether based on CAD models or scale models – does not allow for testing the comfort
of seating and the experience of contact with the designed object. Checking the
proportions and scale of the designed furniture requires creating a 1:1 scale model.
Photorealistic visualizations, drawing documentation, and models in reduced scales
cannot replace this experience.
The standards and recommendations that serve as guidelines for furniture designers
are so broad that they do not provide sufficient data to ensure that objects built on
their basis always meet user expectations. They provide basic guidelines that address
user needs based on anthropometric data. However, this is not enough to give us an
idea of how it will be to sit on a particular piece of furniture.
Let’s imagine that we have to design a chair for the lobby of an elegant hotel. Important
factors here (in addition to basic anthropometric data) will include the following
- how people who will use the chair will be dressed,
- how much time they will spend on such furniture on average,
- whether they will be drinking hot beverages,
- what their body shape will look like,
- whether, when dressed in an elegant suit or costume, they will be forced to lean too
- whether a too-soft upholstery will deform their clothing,
- whether they will slide off a non-upholstered seat, and so on.
Anthropometric data and diagrams for designers provide us with subtle suggestions.
Conscious design requires reflection on many aspects that these tables do not cover.
Working at a 1:1 scale gives the best results but is time-consuming and costly. The
proportions of the seat, angles, and heights have an impact not only on the ergonomics
of the designed furniture. How a person’s silhouette looks while sitting also influences
their mood, appearance, and how they are perceived. Therefore, consciously selecting
proportions and shaping the user’s silhouette is crucial in the furniture design process.
Our lifestyle is undergoing constant changes. In recent decades, the digital revolution
has influenced this. How we work and rest is very different from how people worked
and rested in the 1940s, 60s, and 70s of the 20th century. This is evident in the way
modern offices are organized. Work has become much more flexible and informal
because our work tools have shrunk. The basic tools of a secretary or administrative
assistant are no longer heavy typewriters or giant desktop computers with CRT
monitors. Today, their work tools are smartphones that fit in their pockets, netbooks,
or tablets. In a conversation with Karim Rashid in February 2020, we considered a
similar problem: since our lives and work are so different from those of people in the
1940s and 60s, why do designers still use the same guidelines for design? The most
popular source of information on ergonomic diagrams for designers is the Humanscale
1/2/3 Manual by Niels Diffrient, Alvin R. Tilley, and Joan C. Bardagjy, first published in
- Just look at any photo of an office from the 1970s and compare it to an office in
2020 to see a striking difference.
The main assumption of my project is to create a device dedicated to designers that
allows for the study of the relationship between seat ergonomics and its form.
The project was created as a doctoral thesis at the Faculty of Interior Design of the
Warsaw Academy of Fine Arts under the supervision of Prof. Bazyli Krasulak and Dr.