Team Vision for System-Level Design Phase
- Goals of this phase:
- Break down the overall process of a Keg Washer into
all individual functions
- Determine all inputs and output of the system and functions
- Develop a list of all possible design concepts
- Select one design to move forward with based on a set of criteria important to the project itself
- All above tasks were accomplished and the team's work can be located in the below sections
Below is the visual breakdown of an Automated Keg Washer. This chart decomposes the overarching purpose of the product into individual sub-components and functions.
Many projects encounter obstacles that were unforeseen from the beginning. In order to avoid detrimental outcomes when these occur, teams must develop a risk management plan. This requires outlining as many possible risks as could possibly be anticipated and developing action items for how to handle or manage them before they occur. This will help mitigate the severity of later obstacles.
Possible risks to be encountered in developing the Keg Washer have been recorded and can be accessed here.
BenchmarkingThe following document is a breakdown of existing commercial keg washers and their differentiating features compared to our desired specifications.
Concept Development: Morph Chart, Block Diagrams
The live document can be accessed here
Concept Selection: Selection Criteria, Mechanical Drawings, Analysis
Selection CriteriaIn order to compare and contrast variations of designs developed using the Morphological chart, a list of selection criteria was developed. The implementation of these through a Pugh Matrix format can be seen below using design J2 as the datum for comparison. From the morphological chart, 9 different combinations of designs were created. These concepts can be accessed here.
Mechanical DrawingsDesign 1 The following concept was developed by Brian Bradford. This concept was started using the extent of the customer’s desired footprint of 4.5’ by 3 ft. Taking that into consideration, calculations were done to find optimal dimensions for the storage containers that will contain the sanitation and cleaning solutions. In order to save workable surface area on the base of the device, storage container specs of 0.8’ L x 0.7’ W x 2.5’ H were obtained. This left 12.94 ft2 of free space to incorporate tubing, a CO2 tank, and essential electrical wiring and equipment. Using the maximum available footprint allowed for the possibility of incorporating a second keg into the device as illustrated. Furthermore, this added space allows for implementing the pumps and compressors into the confines of the base, making the device more maneuverable and mobile. This concept is to be considered as ambitious.
Design 2 This concept was developed by John Rueckel. This schematic illustrates a concept drawing of a keg washer size 4.5’ by 3 feet. As shown, it contains a pump, solenoids for fluid control and two containers for solution and sanitizer. The keg stand is placed on the outside of the concept to allow for a convenient loading position, as well as avoid interaction with any equipment contained within the device. A pro of this concept is that it has two separate sections, the front where the keg is located, and the back where all the parts of the washer are located. This concept was further developed using ideas from other conceptualizations, and finalized into the final concept.
From these concept drawings, the team composed one final mechanical drawing to represent the final design that will be used throughout the project.
The final concept incorporated what were considered the best ideas from each team member’s concept. The concept has a grated metal base and two open sides (one for UI placement and another for the keg stand and inlet solenoid valves). On the grated metal base, two used kegs are utilized for sanitizer and solution containment. The pump is placed next to these containers. The minimal amount of equipment located on the base of the concept gives significant leeway in how large the device has to be, and can be adjusted adequately to add or remove components. The keg stand is placed over the containers, both to minimize footprint and to allow for easy chemical return to the storage containers by gravity.
As seen in the tubing diagram for the final concept, several solenoid valves will be required in order to regulate the flow of water, air, carbon dioxide, sanitizer, and fluid through the system. The tubing system was designed around the idea of one pump, and thus uses more solenoid valves than may be required if two or more pumps are used. The placement of these valves seeks to prevent cross-contamination between fluids, and also allow for easy purging of the system.
Feasibility: Prototyping, Analysis, Simulation
- Questions to be answered:
- What will work?
- How will it work?
- Will other options work better?
The following questions are a guide for designing an initial keg washer. All of these were addressed between the benchmarking phase and the concept selection. Since a keg washer is an already existing product with many variations of concepts, the physical prototyping and simulation was not necessary for this phase. Comparisons of existing models and concepts along with research was enough to justify the feasibility until the testing phase.
As the final design is approached, testing will need to be performed. This will occur before moving forward with certain subsystems as well as the system as a whole. Subsystems include the UI and/or interface, control testing and I/O testing. The whole system will need to be tested to ensure proper fluid flow (tubing capacity, pump capability) to determine the keg-cleaning ability.
All testing should take about two to three weeks total, but not necessarily consecutively. Some amount of the budget will be set aside specifically for the testing phase. This will be determined by Brian Bradford, Team Purchaser. Materials that will need to be purchased include the cleaning/sanitizing fluids, pump(s), and tubing. Other materials that will be utilized (at no cost to the team) will include, but are not limited to water/drainage, flow meter/pressure gauge/multimeter, and a sufficient electrical source (120V, 30A). The team anticipates being able to perform tests on campus in the machine shop, material science lab, and the mechatronics lab.
Design Review Materials
To prepare for the Systems Level Design Review our team used the following materials:
- All information gained through the Project Definition
- This information can be accessed at the bottom of the page
- Research material through online sources and
- Information from an interview with Swiftwater Brewery can be accessed here
The pre-read developed for this phase can be accessed here
Plans for next phase
Over the past four weeks, timing of deliverables have changed and more tasks have been added to the Project Plan. The original plan can be found on the Project Definition page. The new plan is as follows with the same cautious optimism that we will finish before week 15 of the second term.