Wheelchair^{2} is debut chair from funhaüs^{2}. It can help you ensure that every day is faster than yesterday.

Wheelchair^{2} is our most advanced wheelchair yet. The two primary features that ensure speed and saftey are our advanced flywheel system. It helps you get more energy while pushing. We also added a very advanced disc braking system, which can stop you very quickly. It can help destroy all of the momentum that is created by the advanced flywheel system. For the outdoor sport enthusiasts, it also features a paintball gun mount, which can even be triggered while you are pushing by using our differential system. All of these features can help us help you achieve your goals.

Here's a quick overview of the two main technologies:

Our advanced flywheel system helps the wheels spin faster, which will give more speed.

Our advanced braking system will help you slow down from the intense speeds that you can gain from the flywheel system.

Heres the science behind it:

A wheelchair works by converting the linear action of an arm push into rotational velocity which then propels the chair forward. This total velocity can be measured in at about 0.65 m/s in children and adults, 0.8 m/s in athletes and 0.48 m/s in seniors. If the normal velocity of an adult on a wheelchair can be assumed to be about 0.65 m/s then the rotational speed of the main, large wheel will be 2.16 radians per second or one rotation of the main wheel every 3.39. The wheelchair has a circular bar over the main wheel. This allows you to push the wheel at a linear speed similar to walking speed. This push bar has a radius of 0.26 meters. Therefore if an average arm push is 100 newtons then the torque exerted onto this wheel is about 26 nm. This torque will decrease if the push bar is placed closer to the center of the wheel this will make it more difficult to spin the wheel at higher speeds. But, if the push bar is on the outside of the wheel it will also become difficult to push at higher speeds because it has a much higher linear speed. This linear speed will be about 0.58 m/s when the wheelchair is at an average speed. When you move this push bar towards the center say about 0.15 meter radius. This linear speed drops down to 0.324 m/s with a torque of 15 nm. This speed allows for continued acceleration at the cost of a much decreased torque. In order to turn in a wheelchair one would need to turn the two wheels at different speeds. Turning is also helped by freely rotating small front wheels.

Our advanced flywheel system is necessary for Geneva’s custom wheelchair in order to add more angular momentum to the rear wheel. A flywheel system will help add momentum the chair because it adds mass to the wheel. Angular momentum uses the equation L=I*ω or Angular Momentum= Moment of Inertia*Angular Velocity. The angular velocity is difficult to change because a human can only push on the push bar so fast, so in order to gain momentum you need more moment of inertia. Moment of inertia=Mass*Radius^2, so therefore when you add more mass to the wheel the moment of inertia increases and then the angular momentum increases as well.

Our specialized braking system works by using bicycle brakes to the main wheels. This is necessary for both of our clients, Jeneva needs it in order to slow down after her acceleration and Sarah needs it to prevent recoil from her paintball gun. Both of these clients would quickly take advantage of this new braking system given their needs. Our braking system consists of bicycle brakes which use friction to slow the angular velocity and therefore the linear velocity of the wheelchair. This braking system will be very easy to install on any wheelchair and the costs will be very low.