Initiating approach to project

Inactive routines in daily work and computerized rest-time extending worldwide result in rapidly growing number of people with back pains and other problems caused by a lack of mobility, as the experts say. The overview in the project shows that people are not changing their sedentary positions at all. The users say: It’s simply too difficult. Therefore there is a certain need for a chair that allows not making any daily adjustments and at the same time providing the user full support in frequent change of inactive positions.

The design process

The office chair concept
 
 

The use of the chair
 
 

The Chair has 3 fixed positions the user can slide among. Each of these three positions is automatically adjusted in height, depth, angle of seat and angle of backrest.

  

Just like fingerprints human spines are not the same, each one is unique. Thus it’s important to adjust the chair to fit the individual user's spine from the very start. Each segment on the chair back is perfectly adjustable to secure the best setting.

 
 
 
 
Morten Mogensen, write@mortenmogensen.dk, Bramming, Denmark, (c) 2007
1. Finding suitable positions
Goal: To investigate the positions of the body compared to back angle. Performed from following criteria’s:
1. Force in the lowest vertebra
2. Bottom displacement force
3. Muscle activity


2. Movement of the body
Analysis to find the curves of the body. The curves are used for creating the initial dimensions of the mechanism.

3. Moving mechanism concept
The concept perform the movement of the curves found from the AnyBody model.

4. Support the body
The goal is to investigate the places on the body which has the greatest demand for support. The investigation is carried out within a number of different static positions.

5. Support the body concept
The chair is divided into a number of segments supporting the body. The appearance of the chair is investigated together with the architecture of the concept.

6. Concept merge
The two dual processes are collected into one concept representing both ideas. The merged concept are further developed in relation to moving mechanism and supporting segments.

7. Mechanical refine and optimization
A number of both physical and analytic prototypes are build, tested and refined. The analytic prototypes are AnyBody and solid works finite element models.
On the picture is an optimization study from AnyBody. The model are optimized from:
1. Mechanical energy in the system (Epot)
2. Compatibly with the body
3. Follow the body movement curves
4. Forces in the mechanical lead
5. The displacement of the mechanical lead

The variables in the study is the length of the supporting arms and the positions of the ends.

8. Form development
The form development is carried out together with the optimization of the mechanical matters of the chair. The two main focus points at this moment is the form of the mechanical system under the chair and the overall shape of the chair.

9. Concept proposal