The problem was for us to design a safe and efficient kitchen accessory our client, James, to relieve strain on his hands without causing subluxations and dislocation so he can perform a task with ease at home given his disability (EDS). For our final prototype we decided to do incorporate a rotating plate on a wooden axle. We thought that this would be the most efficient way of rotating the teapot without putting strain on James’ hands and fingers. We also made our platform from a high friction material, so our platform is covered with silicon sheet. Since we are working with hot water, which can be extremely dangerous, included a safety mechanism so that the teapot does not overpour. Our mechanism stops the platform from over rotating, so the teapot will not overpour as the angle of rotation is limited. Given more time and resources, this device can be improved in several ways. Firstly, we can implement electronics into our design to make it automated. A linear actuator can be used in addition with a touch sensor or a button to rotate the platform automatically and slowly to a certain angle and start pouring from the pot into a container or cup. Secondly, we can use much better materials such as metals and ceramics to make our design more efficient and compact. These materials allow us to make the design more compact as they have easily formed into the required shape as compared to wood which is used currently.
Our final design
Our client James was diagnosed with Ehlers-Danlos syndrome, which has made completing his daily tasks very painful. According to the Ehlers-Danlos Society, "the Ehlers-Danlos syndromes are a group of hereditary disorders of connective tissue that are varied in the ways they affect the body and in their genetic causes.". This means that not every two people that are facing this syndrome will be experiencing the same symptoms since this can depend on the type of their Ehlers-Danlos. This can cause some design challenges for us as engineers since this means that we must learn more about our client's daily life and special circumstances, however, since our design is targeted specifically for James, we can make it more specialized to suit his needs. By going through his Q&As and interviews we were able to get a better understanding of his specific situation. He claims that he can hold anything, however, it's very easy for his fingers to pop out, and as a result, micro scarring has built up and due to the numbness of nerve damage, his hands don't function very well which has been limiting his control and dexterity. This brought us to our problem statement which was to design a safe and efficient kitchen accessory for our client, James, to relieve strain on his hands without causing subluxations and dislocation so he can perform a task with ease at home given his disability (EDS).
As objectives, we aimed to design a safe, durable, efficient, and durable device. However, we needed to make sure that we meet our constraints which included no use of hazardous materials and having no sharp edges in our design since safety was our main priority. After long discussions and research, we aimed to design a teapot that would remove the stress and strain on his hands when pouring tea, especially since it was an issue that had been bothering him. After analyzing existing products, we noticed that since most ergonomic teapots were not aimed at people with disabilities, they did not have any safety mechanism for the tea overflowing and were quite expensive since they were mainly targeting the aesthetics, and that was what made our approach more viable for our client James. By designing this teapot, we did not only hope to help James with his physical state, but we are also hoping that it can reduce the mental stress of thinking about dropping the teapot or overflowing the tea for him.
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.
In conclusion, we enjoyed this project and learned a lot about design process on the way. If we had more time, we think we could have taken a couple different steps along the way. Firstly, we could have created a fully automated design that tipped the teapot with the push of a button or with a sensor. This could have completely taken all strain away from James since he does not have to apply any force whatsoever. We still could have used our exact design, but we could have created a computational component that tipped the plate on its own, instead of James applying a slight force to tip it. Something else we could have done if given more time would be to use other materials that are more aesthetically pleasing and durable for long term use. Some materials that come to mind are ceramic and metal because these materials are nicer looking and are more commonly used in designs like these, however, they are more expensive and less accessible than wood. We also talked about adding some “finishing touches” to our design if given more time, such as something that holds a cup in the exact spot where the tea would be poured, and some type of crate under the cup that catches spillage for easy clean up.
With respect to team dynamics, we learned that listening to our teammates ideas as well as combining our ideas is very important when it comes to producing the best possible outcome. We also learned that it is best that everyone contributes equally and that everyone has their own set of strengths and capabilities. Additionally, our team had the willingness to correct each other's mistakes appropriately, to be accountable in certain situations, and to trust each other. If we were to work together again, we would probably assign different administrative roles as some of us are more proficient when it comes to organization, communication, and time management. For our design process next time, we would allocate time better, possibly build upon our pre-existing technical and non-technical skills and put in a bit more effort.
