Hemi-Seat

thingiverse

The Hemi-Seat was designed with the intent of improving the lifestyles of those who are doing their learning online by disrupting its sedentary nature through the introduction of exercise and posture-correction. The Hemi-Seat has a rubber half-sphere inserted into the bottom of the main body of the chair to make it somewhat unstable, having the user engage various muscles in their core and thighs to remain upright, which in consequence improves posture. The workout is not too strenuous, thus allowing the user to work on their balance and remain upright throughout the day. As the seat is adjustable, the user can insert struts into the chair (the struts clip into the seat, shaft, and main body of the chair for strength and stability) to engage different muscle groups; the lower the seat the more the core is engaged, the higher the seat the more the quads are engaged. Moreover, the bottom half-sphere is removable (if ideally printed out of stiff rubber), transforming the seat into a regular chair. Some issues that had to be overcome during the design was the trigonometry that the design involved, due to the need of circles fitting into other circles and the struts clipping into their proper locations at specified angles. The math was a general headache, but finding solutions to each problem was quite interesting. Another issue was the design of the adjustability mechanism and making it 3D printable. The easiest option would have been to use a pipe clamp and slide the shaft of the seat body up and down, but pipe clamps are outside assemblies that tend to be metal and not 3D printed. Another potential system was one involving worm gears, but the possibility of the gears stripping was too great. The strut system compensates for these flaws by essentially acting like the arches of bridges in distributing the weight of the user, and were an elegant solution to the problem of adjustability. If the chair were to be redesigned something that would be changed would absolutely be the modeling of the struts, since the final product wasn't quite as pleasing as I would have liked it to have been, and it could have been done much more cleanly. A spot in which to store the struts may also be added if a redesign were to be done. Also the components would have been toleranced. 3D printing allows for the customization of various components to the chair that may have not otherwise been possible. For instance, the seat is scaled for someone of average girth, but if the seat were not to fit a potential user it could be easily scaled in a way that with other manufacturing methods it couldn't. Additionally, the struts were also designed with individuals of average height in mind, but due to the flexibility of 3D design they could easily be modified to accommodate someone of higher or lower stature, or even adjusted to add more height settings to the chair.