Table of Contents
From this point on to the end of MSD I, our team began working toward our final detailed design. This page contains snapshots of our progress toward a final detailed design, with the live documents and supporting information contained with the rest of our detailed design information.
Please see our Detailed Design Documents directory for all documents associated with this phase
Feasibility: Prototyping, Analysis, Simulation
A very important process behind our detailed design was analyzing the pressure of the working fluid as it moved throughout our system. A generalized "worst case scenario" analysis was conducted utilizing Bernoulli's equation applied to the schematic detailed below:
The maximum values required for output were applied to the main governing equations listed below, which explain how our subsystem components interact with each other. The values obtained from these equations, such as the pressure that needs to be induced on the chamber, Pc, were critical in our preliminary research for flexible membrane design.
To see our entire Pressure Analysis, see the complete PDF located on EDGE
Flexible Membrane Research
A large potion of this project's success hinges on the successful creation of a functioning flexible membrane that meets the demands of our system. The final selection of our membrane will stem from the following requirements:
- Flexible - Compresses or expands under our expected pressure differentials
- Durable - High # of life cycles without failure or deformation
- Strong - Handles large pressures without tearing or deforming
- Can be molded to desired shape
To gain insight on this matter, Dr. Mix of the University of Rochester met with our team. The membrane photographed below was a prototype he built that was donated to our team for research.
Dr. Mix's membrane was designed in a parabolic shape for the sake of imitating the shape of a ventricle in a human heart. Dr. Mix also noted that the model was very strong and durable for the pressures he induced on it (Pressures similar to that of the human heart, as well as others above and beyond that). For this reason, our flexible membrane will most likely be made of silicon, or similar material.
Click on this link to view our entire meeting minutes from the meeting with Dr. Mix.
DAQ & Pasco Sensors
One of the three major parts of our project (DAQ) involved analyzing the supplied PASCO sensors for feasibility. Unfortunately, after meeting with a PASCO rep, and contacting the companies engineers, we reached the conclusion that the PASCO sensors cannot be integrated with LABVIEW software, which is the driving software that we will be using.
This conclusion was reached by obtaining the Pin-in information (see photo below) from PASCO. Their sensors use a digital format (as opposed to analog) which is the reason they are not compatible with a myDAQ and LABVIEW software.
Drawings, Schematics, Flow Charts, etc.
During the subsystem design, the pneumatic controls portion of the project were further developed through research and investigation of Dr. Day's existing model. Special thanks to Dr. Day of RIT for lending us his extra Pneumatic control system from his current heart pump model.
After a detailed analysis of his system, the schematic of the expected pneumatic control subsystem was developed
To get preliminary ideas of system size, setup, and general appearance, a 3D model was constructed. The driving dimensions of this model were from our flexible membrane's required volume, which would dictate sphere radius. All other components of the system were then modeled to fit the sphere's radius.
Creating a 3D model also aided in the generation of a Bill of Materials (BOM), outlined later on this page, as each individual part required for assembly was modeled and added to the system:
|Flexible Membrane (Colored Yellow)||One Way Valve (OWV)|
You can see all snapshots and revisions of our 3D model in our Photo Gallery Page
Updated System Architecture
Based off of new information obtained from the subsystem design cycle, the systems architecture was updated
Bill of Materials (BOM)
See a link to the live excel document here
See the live document here
Design Review Materials
Plans for next phase
At the end of the cycle, the following charts were constructed. The first chart represents an overview of where the group should be by the next cycle, and the second chart represents these goals in more detail, split up based off of the three main subsystems of our project (Controls, DAQ, Mechanics/Hydraulics).