Process 2

Ethan Wood
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        The wheelchair is one of the best inventions to help disabled people. It can easily transport people from one place to another safely without having to use a person's feet as a means of transportation. However, people in wheelchairs are extremely limited in a number of activities they can do. They can't go certain places, they can't reach certain things, and most importantly the interaction is not quite the same. For kids, one might feel included as they are unable to play on the carpet with the other students. Juan an elementary school student expressed these problems to us and felt he needed a solution to solve his problems. The uplift wheelchair is a regularly sized wheelchair that has the capabilities to lower and expand fully outwards to the ground. 

         This second version of the Uplift wheelchair uses a suspension and gear system to lower the chair to the ground. In an upright position the wheelchair looks identical to a normal wheelchair, however when unlatched from the back, the chair can be slowly lowered to the ground. For support, there are two beams attached to the base and wheels. The beams bear the weight of the user and multiple springs assist the chair, resulting the a smooth lowering motion.  In order to support the full weight of Juan, the wheelchair also needed support in front so it didn't tip over. This is why gears were added attached to the parallel beams. I had to do a lot of experimenting with the placement of the beams to that the chair clears the wheels, but in the end this position was chosen because of the front beams. I knew that these wanted to be able to expand with the chair making the center of mass always be over the wheels, but I didn't know how to fix them in place. The whole point of the gears is for the front beams to actually bear weight depending on the suspension speed in the springs. Once lowered to the ground these beams would support Juan's feet and keep him in a relaxed position. To go back into his locked position a helper or teacher would simply push on the back of the wheelchair with his or her foot on a pedal and with a certain amount of force, the chair would raise back up. While this would need a huge amount of force, the springs would add enough tension and pressure to make this "release system" easy to engage and disengage. Once in upright position the springs would relax and to keep the chair from falling, a door lock mechanism would be placed on the chair to lock the seat in place with a click. This would be the only mechanism needed to engage and disengage the chair. 

          While a lowering and raising wheelchair is already out on the market, our wheelchair would have significant advantages over them. Firstly, the price range of an automated scissor lift chair is between 15,000 and 30,000 dollars. Most disabled have income problems as most cannot work and so this wheelchair is way out of their range. Our chair would be a few hundred dollars, and as most of the cost is the chair itself with all of the padding. Our chair would just come with a base and with a few bolts, one could take their fully functional chair and attach it to our base while still using their wheels and expensive parts. This wheelchair would be useful to all kids and adults who wish to be included in activities that they should be able to participate in but can't, due to their disabilities.

Process

Stefano Pagani and Ethan Wood
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Uplift 2 is a continuation of the original Uplift project, which was successfully demonstrated at a school for children with Cerebral Palsy in Monterrey Mexico. The original project was designed to provide low-income families, living in very small homes with a ultra-low cost alternative to transporting their kids around the house. We were contacted by another school in New Hampshire to help them create a way for one of their students with cerebral plays, Juan, to be more engaged in the hands-on classroom activities. We couldn't simply use the original chair because it was designed for indoor use to lift the user while Juan's problem was that he could not reach the ground level plant beds that are used in some of their classes. We still wanted to create a wheelchair that was affordable, but we also wanted the chair to last Juan many years.

We decided to take an entirely different approach than in the original Uplift project and create a wheelchair lift attachment that could be used in many different chairs. We spent allot of time looking at the lift mechanism, looking for simple ball-screw mechanisms to full on hydraulic lifts. We eventually settled on a scissor lift design as it can collapse to a fourth of its extended size. We looked at two different versions of a scissor lift design, a more basic design where the top and bottom anchors of the lift slid on rails and a more complicated one where the rails were replaced with levers attached to each other to replicate the sliding motion. We chose the more complicated design because the sliding rails had many downsides, mainly that the chair could rock front and back as well as side to side, even with the lift locked. We made a motorized version of this design where the lift is pulled up with a ball screw. In the next iteration, we plan to make an attachment system to affix the lift to the wheelbase of the chair.