Team Vision for System-Level Design PhaseDuring this phase, the team used the Filabot as a benchmark in order to get a preliminary idea of what the product's design should be. After a thorough inspection of the Filabot, the team got a solid foundation which enabled the start of brainstorming ideas for a new design. The most important aspect of the design was to decided the system's orientation. Two team members chose a vertical orientation while the other two chose a horizontal orientation. Based on the customer and engineering requirements, the four designs (Vertical A, Vertical B, Horizontal A, Horizontal B) were evaluated and rated against each other. Vertical A was the chosen design due to it being the choice which most effectively complied with the determined requirements.
At the same time, subject-matter experts were consulted in order to determine some aspects in which the team still requires background information. As determined from the previous review's plan, Dr. Ghosh was consulted regarding the mechanics of the nozzle and the lead screw. More advice on other subjects will be sought as the system design becomes more detailed.
A Functional Decomposition of the system was developed in order to determine the key functions of the product. It was determined that the extruder will require six main steps:
- Loading the material onto the hopper
- Moving the material into the barrel
- Heating the material to a melting point
- Shaping the material into a filament
- Cooling the filament
- Spooling the filament
The Filabot belonging to The Construct was used as the main benchmark. Also, a Filastruder was analyzed mainly for its effective spooling system. Some positive aspects found:
- Readout is good, easy to use and follow.
- Filastruder Spooler is simple and works well.
Some areas for improvement are:
- Braided cable is not good for taking apart.
- Wood frame is good but small, the nails used are a poor choice.
- Design is too compact after insulation is added (had to squeeze it back together)
- No heat creep prevention methods
- No spooler system is included
- Heating element takes a long while to heat.
- Filament diameter varies quite drastically.
Feasibility: Prototyping, Analysis, Simulation
A concept model for a roller system was designed and 3-D printed in order to test the feasibility of using this system on the final design.
Inputs and Source
- Engineering Requirements
- Concept Selection
Outputs and Destination
- A list of Design Parameters, Quantified Targets, and acceptable tolerances
- Sensitivity analysis
- Concept Selection
Morphological Chart and Concept Selection
A Morphological Chart was developed based on the different steps the system will need to fulfill. This chart was then used to start building combinations for potential system designs.
Each design included at least one of the options provided on the table. For example, design Vertical A included a Vertical Lead Screw to move the material, Shaping Wheels to shape the filament, Fans to cool the filament, and a moving spool for the spooling system.
Concept Screening Matrix
The selected design will be further detailed as the team gets more information regarding heating and nozzle dynamics.
Designs and Flowcharts
PurposeDefine a high-level view of the elements required to build and operate the entire system
The team identified new risks that would have to be considered for the development of the extruder. One such element that had not been considered before is the risk of equipment malfunction due to thermal expansion. In order to mitigate this risk, the team will have to calculate the possible degree of expansion and compensate for this difference. As the design is refined, more risks will be identified and dealt with.
Design Review MaterialsInclude links to:
- Pre-read: https://edge.rit.edu/edge/P18676/public/Systems%20Level%20Design%20Documents/Pre-read.pdf
- Presentation : https://edge.rit.edu/edge/P18676/public/Systems%20Level%20Design%20Documents/Design%20Review%20II%20Final.pdf
- Notes from review: https://edge.rit.edu/edge/P18676/public/Systems%20Level%20Design%20Documents/Notes_and_Comments.pdf
Plans for next phase
TeamThe System Design Review proved to be a very useful step in our design. We got valuable comments from our guides and customer, and we feel as a team that we are aptly prepared for the upcoming phase of the project.
After the Review, the team got together to begin planning the next steps in the project. We broke down the tasks by team member. It was agreed that we have reached a point in the project where we can all focus on one aspect and delve deeper into its development. We documented this on a Responsibility Matrix, which will hold each owner of the task accountable for their assigned tasks. Once a week, the team will report the status of their tasks. This way, we will be able to meet our goal on time for the next review.
Individual Team Members
Each team member is responsible for the tasks they were assigned. For these next few weeks, we each identified the specific steps required to accomplish these tasks, and documented them in the plan found below.
3 Week Plan documents for all team members: https://edge.rit.edu/edge/P18676/public/Systems%20Level%20Design%20Documents/3Week_Plan_Master_List.pdf