Have you ever been wrapping up after a long shower and you throw your towel onto the hook just for it to fall right back down onto the floor? Have you ever returned two hours later and your towel is still wet and starting to smell? Well this issue is precisely the reason we started to develop the Extendo Hook.
The very first Idea that came into development was a simple hook with a two inch bar mounted on the top. The idea was to give the towel as much contact area to create as much friction as possible. To make the towel catch onto the bar even more, we decided to make the edges of the bar sharp so that the towel would catch on the corners if it were to start to slip. But this prototype had some major problems. The bar we had made was not large enough to hold the towel apart and keep it from overlapping on itself. Because it wasn't able to seperate the towel, the towel wouldn’t dry and would eventually start to smell and potentially become moldy.
The solution that we came up with was something similar but it replaced the two inch bar. The two inch rectangular bar was replaced with what was more of a circular chip with jagged edges. When the towel would land on the top of the hook it would immediately spread apart because of the larger circle. The reason it spread so well was that the circle expanded in every direction, unlike the bar which expanded more in one way than the other. The jagged edges served their purpose extremely well. They always caught the towel, meaning every time the towel came into contact with them it would hook on. But after testing it multiple times, a problem arose. The jagged edges that caught the towel so well also started leading to fraying of the towel. As a possible fix to this we tried to dull down the edges, but after doing that we found the towel didn't catch nearly as well.
After reevaluating and circling back to the brainstorming process, we came up with something new. We decided to start on a spring loaded hook that would fold up into a hook but when weight was applied it would fold down and become more of a bar. This idea tackled a few of our main problems. First, it kept the hook small and not too obtrusive. Second, it spread the towel apart meaning it would dry and prevent mold. And finally, because of the ability to expand and increase the contact area with the towel, it held the towel better. It did this all by being able to fold into itself as the entire hook could move. But this created yet another dilemma. How would we mount it? If the whole thing moved we had to be careful in mounting it not to limit its movement range but also, not to allow too much movement range. I solved this problem by making a guiding rail system that led into a block from which the hook could be mounted. The guide rail essentially took a bolt going through the top of the hook and connected it to the end of a cylinder which ran down into the block but could only go so far down or up. This solution also solved the issue of the hook wobbling side to side as it restricted this kind of movement.
The next step to improve this project would be to find a spring with the right resistance so that it gives in to the towel, but will push the hook back into position. The best place to mount this spring would then be over the cylinder as it will prevent the spring from pushing too far up. This way the entire process would be automated and would be of little concern to the user.