Did you know that the height of a 1 story home gutter is around 9 to 12 feet, and the height of most ladders extends anywhere from 12 to 21 feet With the average height for people being around 5 foot to five foot 10. This means that if you had 5ft or 2ft tall stilts your would be able to reach the gutters on your roof. But the applications don't just stop there. Where did the idea of latter boots begin, well a classmate mentioned carpet slider shoes and thought it would be fun to have those with poles on the end to make you taller. That conversation eventually evolved into the idea of ladder boots.  How cool would it be to be able to walk around at a height of your choosing.  This could help you clean the gutters, paint tall parts of your walls, change ceiling light bulbs, etc.  

 During our planning phase of the project, we had a lot to consider. There are so many ways to make extendable and retractable heights, but no matter how many designs we tried we kept landing back on the scissor lift idea. We made a rough prototype out of popsicle sticks, drilled holes in ends and connected with nails. That was hard to make accurate and it was quite flimsy, so we decided to use legos, and quickly made a multi-layered scissor design.  This convinced us that the approach was quite doable.

It allowed us to see in more detail how the mechanism its self would work, better than any of the simulations or videos online ever could. It was after that we began to brainstorm what our product should be made out of. We considered a lot of materials -- angle-iron, aluminum, wood, rods.  Our criteria were that we wanted to maximize strength and stability while minimizing weight and cost. It wasn't just the material it was the shape or kind of material that matter as well, for example, while flat iron bars are strong for horizontal loads, at a vertical angle they are quite flimsy so we had to make or design carefully. Of course, we also had to be sure it had to be able to move up and down.

Then we had to focus on how we were going to raise and lower the system. At first, we considered a threaded bold design that pulled the scissor together thus pushing the shoes up. However, it takes a lot of turns of the bolt to fully extend the screw. Our solution to this was we thought the lifting of the foot might cause the screw to spin and the scissor to expand, but we found that that was not the case.  We briefly considered abandoning the idea of a screw in the lift in favor of a hydraulic mechanism that we saw in commercial scissor lifts.  But that seemed too expensive.  So we decided that we needed a motor on our screw. Because of the poor transfer of a vertical to a horizontal force the motor would not need to work very hard, just very fast.