Preliminary Detailed Design
Team Vision for Preliminary Detailed Design Phase
The beginning of this phase began with a slight redesign of our testing fixture. In place of a tachometer, we were informed an encoder would be much more accurate in measuring rotational data. We also needed to incorporate a brake into our design such that the torque could be changed on the load end.
The primary goals of this phase were to create a CAD model of our final manufactured testing fixture, to build a preliminary prototype for our design, and finally to gather and organize more information from subject matter experts moving forward into more detailed design. All of this was accomplished, bringing us further along into detailing our test fixture design.
The live document can be found here
To the left is a screen capture of the final project plan for this phase.
Going into the Preliminary Detailed Design phase of the project, we needed to be able to disassemble the DIS system to see exactly how the subcomponents interacted with each other. From here, we would then be able to even more accurately design our test fixture, and even be able to use some of the parts from the disassembled DIS system. This process detail also provides valuable pictures of the interior layout of the DIS system. The following document contains the detailed disassembly we carried out:
Drawings, Schematics, Flow Charts, Simulations
One of the first things we did after our last gate review was to go back and understand our system. To achieve this, we went and visited the NexPress system here on the campus of RIT to revisit the system.
After revisiting the NEXPress, we went back to the drawing board to improve our design:
A preliminary design was created in SolidWorks to baseline our prototype. Below is the 3D view of the model:
Prototyping, Engineering Analysis, Simulation
Starting to build a conceptual prototype began with breaking down the CAD model and dimensioning parts:
From there, we purchased basic building materials (wood, brackets, screws) to complete the prototype:
This prototype is a proof-of-concept. It shows where components are going to be located, which components move, and which components are fixed. Building this preliminary prototype helped us to visualize what we needed to now optimize for testing. From here, we will be able to decide where we can save material and money, as well as where money needs to go to ensure the integrity of the fixture is upheld.
Feasibility: Prototyping, Analysis, Simulation
We disassembled the DIS and learned about parts and their function inside the DIS. This gave us a better understanding of how to design our prototype. Our current prototype has a stage, and it will be revised in our final design. The current stage causes undesired vibrations in the design. We learned that we need better support for our coupling. We wanted to use the motor used in the DIS, but it is a three-phase motor. We are not completely sure how to use it yet, so we are considering using a different analogous motor. Now that the parts in the DIS are visual, we have an easier time with communicating about the parts. We intended to exchange the coupling in the test setup using the xyz-coordination system, but now we feel that it will be more feasible to have a one-axis sliding output shaft.
Bill of Material (BOM)
A preliminary Bill of Material was drawn up both for specifically the next phase and for the final prototype:
The live copy of the spreadsheet can be found here.
Preliminary requirements were compiled in order to understand what type of power supply we will need. The following pseudo-circuit diagram lays out the requirements below:
Preliminary Test Plans
PurposeDemonstrate objectively the degree to which the Engineering Requirements are satisfied
In order to ensure all engineering requirements are met once the final prototype is complete, test plans are drafted. Preliminary test plans for specific engineering requirements are linked below:
Engineering requirement 7 is as follows:
Testing to ensure the product meets these requirements is simply to measure the maximum protruding dimensions of the fixture (in x, y , & z) and compare them to the above specifications. A passing test occurs if and only if the measurements are less than the specified dimensions.
Design and FlowchartsThe project flow chart was not significantly altered from the flow chart created during the systems level design documentation. The flowchart is displayed below:
A copy of the live document of the Testing Fixture Use Flow Chart can be found here.
A copy of the live document of Risk Management can be found here.
Plans for next phase
In the upcoming weeks as a team, we look forward to further detailing our design and beginning/defining the second portion of our project: Improving the coupling subsystem within the DIS system.