
This is the solution that VICAIR found, and patented. Air elements made of a tube and two seals. The have a smooth/slippery surface. They would turn leak easily, so that makes them very secure to use. Compared to the ideal airball element, they are cheap to make. But these air elements have 4 sharp corners that can sometimes really sting through the cushion. Not a good idea to press corners in a pressure sensitive skin! I do sleep on a VICAIR matras, because it's so secure and silent, but I regularly have pain from the points.
This is the solution I found for my LaesieCushion: very flexibel though non stretching bags. These bags don't need a very smooth surface, because there's no need for the air elements to move. As they are only filled to about 20%, the air inside can move around freely. I sealed these bags myself, as I couldn't find ready ones for sale.
I have a lot more comfort sitting on them instead of the VICAIR elements, but my air elements do leak a bit air, so I have to quick-check the cushion every day.
HOW TO MAKE YOUR OWN LAESIECUSHION
(for your personal use only, not to sell)
I would only suggest the "model 4" because it's more stable, has better ventilation, and gives even less pressure on the sit bones, IF positioned right.


FOR WHOSince every person is unique, my design will not be ideal for everyone. I'm 190 centimeters tall, and paralyzed up to my shoulders. If you can move much more of your body, then you'll probably be better of with an other -thinner- cushion.
SIZEThis cushion is made for my size (see picture). Children would need a smaller one, and wide people a bigger one. Too small isn't good, obviously, but too wide isn't good either! (the bags want to pop out sideways). Mine is about 8 cm wider than my hips are.
BOX
There must be a box! This type of cushion has an absolute need for a box that supports the cushion's bottom and sides. I see people sit on VICAIR cushions without a box. Then you could as well sit on a cheap piece of foam, because the surface tension becomes really high without the support of a box.
- Make many small holes in the box-bottom, to improve ventilation.
- The front should be lower, because you really don't want your legs to touch it.
- The back of the box should be lower also, especially in the middel. Beware for chairs with variable back support. Your back may not touch the box.
THE OUTHER BAGS
This part is really hard to make. I found coated nylon ripstop fabric used for kites and parafoil, to be the best choice, because this material is very thin and strong, and dries really fast too (
image). No need to make it green like mine, there are many colors to choose from. Use a strong synthetic kind of thread. The four zippers need to be long, so a change or check of the inside is easy. (about 37 cm each, in my cushion)
THE SEALED BAGS
I use a particularly kind of.. urine bags (new ones!), because they are airtight, strong, flexible, and can be sealed. They are expensive. You'll also need a sealer and a simple feet pump. I searched for an alternative, but other bags I found were either too hard or too weak. Please
let me know if you find a good alternative.
CLEAN
The LaesieCushion's outside can be hand washed easily, and dries really quick. You don't want to wash all the air elements, so that's what the plastic bag is for. I use two slightly oversized plastic bags to protect the air elements. In case of a little accident, the inner bag stays clean, and the outher bag can be thrown away.
FRONTThe front part is at the bottom filled with 4 cm foam, to support the position of the main cushion. The remaining space (8 cm high) is filled with the airbags.
HELPThe LaesieCushion isn't easy to make, so you'll probably be better of working together with someone really handy.
Last note: Boys have an extra problem, or two actually..
Therefore I place a small piece of foam inbetween the front two airbags (between 1 and 2), to create a bit more space there.
OK, good luck with it. I would really appreciate your feedback if you build one.
Giesbert Nijhuis