After a tutorial with huw I realised I was getting bogged down with the idea that this had to be a chair, maybe it could be an attachment or a wall mounted piece. The idea of it being wall mounted seemed to solve a lot of problems for me, but it also posed some new ones.
With it now being a wall mounted piece it meant that I would be able to make the thing rather than make a Maquette as making a chair is a challenge in itself with the time constraints of this project. It also meant that there wasn’t so much stress as to how I would make it to accommodate different uses of different sizes, instead of it being a fixed thing (chair) having it wall mounted meant that I could make the height interchangeable by having different height fittings.
I decided to have a look and see if anything like this already existed and whether there was a market for this type of thing.
The first was this single ball roller that is used for specific point in the back, this attaches to the wall using an industrial sucker.
The second was something that was similar to my design however it doesn’t seem allow for different sized people, its would also be difficult to use for other parts of the back other than the spine itself. 
This third one is slightly similar in design but you can see the obvious problem that it is difficult to massage the lumbar section of the back due to its shape. 
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