A Dish Washing Dilemma

Design Objectives:

The current problem is that hand-washing a load of dishes (after a meal undertaken by four people for example), takes too much time and energy, as well as encouraging waiting until everyone’s dishes are able to go into the sink at the same time. To solve this problem we would like to propose a design brief for a product that can replace the current hand-washing method and compete economically and time-wise with the current dishwasher.

-          The goal of the product it to effectively wash dishes while:

o   Reducing the amount of time necessary to clean the total amount of dishes (Compared to regular hand-washing)

o   Reducing the amount of work necessary to clean each individual dish. (Compared to hand-washing)

-          The product should also be able to clean an individual’s dishes quickly, so that it does not encourage waiting for a full load of dishes before cleaning.

-          The product should also be as economical as possible, something that a low-income family or university student should be able to afford. 

-          The product, if possible, should use as little water as possible in the cleaning process.

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Above is a draft of my Praxis I group's proposed design problem along with the problem's objectives. I personally feel that this part of the project, though it was key to the project as a whole, does not have much relevance in terms of my development as an engineer. It gave myself and my group opportunity to, for the first time get a chance to really go through a brainstorming process, a key element in my current design process. It also introduced us to other elements in the engineering design process such as properly framing a problem into what would later be known as an RFP. It allowed us to practice in these and other areas such as creating objectives, criteria and constraints. It gave us a great way to learn these elements - our group was told that we had "over-constrained" the problem and that it would only result in one possible solution, which was something we were able to grow on for future framing problems.

CIV Bridge Construction

This a assignment sheet from our much bigger bridge design and construction project. Looking back, there was not much change in the way that I approached this problem compared to the previous bridge problem (see here). My group and I approached it with an extremely similar mindset: find the simplest solution and then use that to accomplish the problem. However, in this project we did look slightly different possible designs. Our first choice was a simple I beam, and when I say we looked at other designs, I simply mean that we looked at variations of an I beam. In that aspect, I feel that I had not learned very much between the first CIV project and this one. But in the aspect of prototyping, I learned a lot. Because we had to construct the bridge that we were designing, we had to calculate how much of the mat-board that we should cut and how much we would be able to use to construct it. So from this project, I drew the importance of the time spent before actually building the prototype - the time spent planning the build. My group had to re-do the calculations for the dimensions of each section multiple times. This seemed to be the most important process of the project and took up the most time and effort. 

The Design of a Truss Bridge

This was the first, I think, real design problem that I was faced with in Engineering for that reason alone it is very important. Compared to the way that I now solve design problems, the Truss Bridge design is a complete embarrassment. Every group was given the same problem - to design a truss bridge that would be able to support a certain weight and span a certain width. I met with my group and we put almost no thought into what the shape of the bridge would be, or how many components it would have. We decided it was a truss bridge and so we would build it as the simplest truss bridge that we could. Perhaps there was a bit of laziness involved in that decision as well as naivety. So we drew it out and calculated the load and how much it would be able to stand and we found out that it would be able to solve the problem. We didn't think of any other designs of bridges we could have built at all. It came as a shock during presentation then, when the other groups talked about how they had "calculated the optimal bridge design" and "looked at 10 or 12 different designs before choosing this one" when we had simply stuck to the first design that we had thought of - the most simple and intuitive design. I'm not saying that's wrong, but for my first design experience, it certainly was. This opened my eyes to the possibilities and the amount of work necessary to go into any engineering design process. It made me understand the importance of considering many designs before selecting one that you have determined to solve the problem in the best way possible and the importance of brainstorming creatively and not just choosing the easiest or the most intuitive solution - something that has become very important in my personal engineering design process.

Above is a sketch of our solution for the truss bridge problem. As is easily seen, we simply connected the span with the nearest to equilateral triangles that we could.

Above is a sheet showing the types of HSS bars we eventually chose to design our truss using, as well as some of the force calculations on the side.