Using the finalized morphological chart, four main concepts, Concept #1-4, were initially generated and further explored . Method development and detailed descriptions for each individual concept is as follows:- Concept #1: With the level of knowledge that the team has thus far, Concept #1 seems to be the least ideal concept to solve the problem. For starters, the float switch is an electromechanical device poses a risk of overflowing the system due to the potential for the float switch to get stuck. Based on the benchmarking from Phase 1: Problem Definition, Z-wave kits are very expensive which may cause the team to go over budget. As far as fuel transport goes, the mechanical engineers on the team have suggested against capillary action and using a hand pump due to not meeting the customer requirements of aesthetics and potential problem with transporting enough fuel to the individual torches. To ensure the torches are stabilized and wont leak a combination of burying the base of the torches in the ground and using flex seal was selected. Each of these selections are very likely to cause problems that may miss the customer requirements and break over time.
- Concept #2: The team developed concept #2 with the intention of being realistic and effective. This concept utilizes a differential pressure sensor for fuel level sensing, a WiFi/Bluetooth combination communication system, butterfly valves to direct fuel, and electric pump to pump fuel to different torches. To avoid fuel leaks, O-rings would be used to help seal the fuel lines and the base of the individual torches will be filled with sand, gravel, etc. to prevent any of the torches from falling over. Our team believes this concept meets most if not all of the customer requirements and overcomes several constraints.
- Concept #3: This concept is another realistic selection of solutions. The team selected all different components with the exception of the electric pump from concept #2 in order to consider a variety of components. An Ultrasonic sensor, Zigbee communications, and one way valve were selected for the fuel level sensing, communication, and fuel transportation systems. The team chose to stabilize the individual torches by using yard stakes and prevent leaks in fuel lines by using caulk. Similar to Concept #2 this meets the customer requirements and overcome the majority of design constraints.
- Concept #4: Concept #4 is also a competitive option as it was also approached in the same way as Concept #3. A Laser transmitter, IR communications, pressure sensitive valve, and natural suction are combined together to achieve the main functions of the BugTorch. Magnetizing the base of the torch provided a solution for holding the torch in an upright position although it may not be as effective as we want it to be, but allows for more placement options across a yard. Pipe dope would be used as an adhesive to prevent leaks in fuel lines. Each solution is somewhat reasonable and meets most of the customers requirements and constraints.
Each of the concepts are summarized in the table below and evaluated using a Pugh Chart. The objective of the Pugh chart is to compare how each of the solutions rank amongst each other and further described in Section 7.
After a discussion with team mentors and experts and completing some benchmarking for the system level design, some revisions were made to the Morphological Chart and the team added Concept#5 and #6. One of the experts in attendance to the discussion suggested the team look into capacitive sensors to detect the fuel levels. Due to a signed agreement between one of the team members and another company, cause the team to immediately dismiss of a capacitive solution without any further research, but after some advising from experts and mentors, the team added the capacitive sensor back on the Morphological Chart. Another suggestion made was to eliminate the differential pressure sensor to detect the fuel level. Once the team was asked to further elaborate on our intentions for integrating this type of sensor into the system, the team realized that this solution was no longer feasible for our design and would be ignore in when considering alternative design concepts for the torch. Additionally, during the benchmarking process which will be discussed further in a Section 7, irrigation products were suggested to purchase based on search history and placed on the morphological chart as another feasible design solution.
After the Morphological chart had been updated, the team added two additional concepts that compared to Concept #2. The differential pressure sensor would be replaced by an ultrasonic sensor in Concept #5 and a capacitive sensor in Concept #6. This was done since Concept #2 initially ranked #1 in the Pugh Chart.
Relevant Files
