Our team was set on designing a device to help our client pour tea right from the very beginning. We chose this problem based on our strengths and capabilities regarding the mechanical design process, and we knew that this device would be something that our client would be using almost every day. Our brainstorming was inspired by other tilting devices on the market that tilted objects manually or automatically. During the concept exploration stage, our sketches (Figure 7) were quite similar as majority of them had an axis of rotation and a specifically dimensioned teapot to fit the base it would be rotating on. Other alternative designs consisted of a teapot with an attached nozzle that would dispense the tea as our client pushed down on it and a teapot that was free rotating on a rod-like structure. Unfortunately, these designs were not practical and thus our team developed three other concepts throughout the duration of the following Milestone.
These designs were the spherical design, axial design, and the rotating design. The spherical design was creative yet lacked adaptability and efficiency. The axial design was functional, efficient, and adaptable. The rotating design, when compared to the axial design as seen in the decision matrix (Figure 10), demonstrated creativity. Based on our decision matrix, we decided it would be best to implement the strengths of both approaches to ensure the highest quality product.
With respect to the feedback from IAIs, TA, and Science Students, we were asked to put the safety of the client first (i.e., ensure that there was a safety mechanism and reduce the gripping movement that our client would use if he were to pour tea regularly), to consider making the design adaptable (i.e., consider making our own teapot or kettle), and to ensure that it is easy to maintain. Going forward, in Milestone 4, we combined two of or previous prototypes, a pulley system and a rotating plate on a wooden axle. Additionally, we included a mechanism that stopped the rotating platform from over rotating and cut out a side of the wall so that the tea pot has more room for rotation (Figure 13). Nevertheless, the feedback from our mentors was extremely insightful and granted us to improve our prototype for maximum efficiency.
For our final design, we decided to implement a tipping mechanism that takes the weight of the teapot onto a plate and only requires a slight force to tip the teapot. On the plate, there is a silicon sheet, which creates a high friction surface for any teapot to sit on without slipping. Under the plate, there is a rod that restricts the plate from tipping too much to ensure that James will not harm himself with hot water. This design still requires James to apply some force, but his biggest concern was the weight distribution of the teapot. Our design takes the full weight of the teapot onto the rotating plate, so with a little help from gravity, James is able to pour his tea without enduring that weight distribution on his hands and fingers.
Our 4 objectives were safety, durable, efficient, and portable. As mentioned above, we implemented safety mechanisms, such as the high friction surface and the stoppers, to ensure that our design was safe for James’ use. Since our client is handling hot water, safety was our main priority within this design, so creating a surface with a higher coefficient of friction, m, and restricting the angle q that the plate is allowed to move was important for our design. Our next objective was got our design to be durable, and we decided to use wood as our main material in making our final design. Wood is a very strong and stiff material, with a very low young’s modulus (8.7-15 GPa), meaning our structure will be firm and it will not bend or stretch. Again, since we are dealing with hot water, we needed a strong and durable material, which is why we picked wood. Our next objective was for our design to be portable, so it does not interfere with James’ family members. Our design weighed around 15 pounds, allowing it to be moved around with ease and put away when it is not being used. Our final objective was for our design to be efficient, which was the most difficult one, due to all our constraints. Since we restricted the rotation of the plate, the teapot can only pour a certain amount of liquid before the angle exceeds a certain limit and no more liquid can pour. When the liquid is pouring, it pours swiftly and it easily reaches the cup, however, safety was a bigger concern than the efficiency of our device, so we had to make some compromises.
As mentioned above, we decided to fabricate our final design out of wood. We made a 26x26cm box without a top side, and then drilled 2 holes into the sides to put our wooden dowel through. Nailed to the wooden dowel is a 15x15cm wooden plate and glued onto the plate is a silicon sheet to create a high friction surface for the teapot. Under the plate is another wooden dowel, that acts as the safety mechanism to restrict the rotation of the plate. Wood was ideal for our final design because it is inexpensive and accessible, while being strong and durable. In total, the wood, the screws, the silicon sheet, the spray paint and the wooden dowels costed around $50.
