Team Vision for Detailed Design Phase
During the detailed design phase, we planned to determine the final processor design and its compatibility with the wireless system for the easiest and most efficient implementation. Additionally it is important to understand how the quadratic measurements can be converted to a form that can be interpreted by that processor. Another priority is to understand how the application will communicate with the hardware. Lastly, in addition to determining a final requirements document, a final housing design should be established that is both sturdy and user-friendly.
Not only were these plans all accomplished but a progress report was drafted and shared to our customer in order to update them on our progress. Old documents were also updated to reflect a more complete state, including the risk assessment and bill of materials. Additionally more feasibility analyses were constructed in parallel with flow charts detailing the process of various subsystems in the project whole.
During the detailed design phase, our team plans to address and complete some of the final key bullets in our plans for our final project. The final steps consist of a few critical design choices and follow up documentation on the project whole. Determining the final processor design and its compatibility with the wireless system is our biggest goal, in which we plan to have successfully sorted out some of the essential set-up of the Pi In addition to more direct operations, our team will also be doing some final research to verify that we understand how quadratic measurements will communicate with the project systems hardware and be converted to a form interpretable by our selected processor design. It will also be important to understand how our application will communicate with our hardware as it will help for smoother implementation and faster debugging during the application construction phase in MSD II.
More on the physical spectrum of things, final details will be sorted out for the housing construction that will protect our final product that will encompass a robust and user-friendly package for protecting the project. After this the primary remaining steps consists of properly documenting the remainder of our project by working towards a detailed list of all the final requirements for our product, and updated risk assessment section, and a finalized Bill of Materials to details the parts needed for our project.
During the detailed design phase, the following tasks are planned to be addressed and completed:
Task - Owner:
- Determine the final processor design and its compatibility with the wireless system - Dylan/Andrew
- Investigate how quadratic measurements can be converted to a form that can be interpreted by the processor - EE Team
- Understand how the application will communicate with the hardware - Anthony/Fernando
- Implement a final housing design that is user-friendly and sturdy - Mathias
- Develop final requirements - Team
- Update risk assessment - Anthony
- Finalize Bill of Materials - Mathias
The final processor design was the teams primary focus for completion before our departure for Thanksgiving break. The final selection is a Raspberry Pi and evidence to its viability was shown through the demo. In addition to our primary focus, a portion of edge page documentation was completed giving general summaries of currently relevant material to our testing phases. Lastly more updated versions, though not finalized, of the Bill of Materials and risk assessment documents have been created.
The following tasks have been accomplished before Thanksgiving departure:
- Determine the final processor and its wireless compatibility
- Edge page documentation
- Updated Preliminary Bill of Materials
- Update risk assessment
All remaining tasks are targeted to be addressed upon reconvening after Thanksgiving break.
The project currently has a number of associated details to it that have already been determined up to this point in time. We have established a standard sampling rate for 9 channels of data to be taken on the hour at a 1kHz frequency for 2 seconds. This sure ensure ample data points for proper accuracy in FFT calculations and PV diagrams. All of this data will be stored and written to an on board SD card which should provide more than enough space for several approximate years’ worth of data requisition. This data will transmit wirelessly using Bluetooth hardware which has been shown to have the best and most reliable transmission rate for our needs.
The device itself will be wrapped up in a sturdy, lightweight, housing of ABS Plastic to give it protection without causing interference like a metal housing would. We will be using the original sensors on the compressor and feeding their data into Mini XLR ports on our final product which will be a contained Raspberry Pi housed in the previously mentioned plastic. In order to display the active, error, or other conditional state of the device, an LED light will be used and capable of being turned on, off, or blinking error codes. A button will be favored over other means such as a switch as it provides multiple input states such as pressed, held, or multiple presses that can outshine the binary states of ‘off’ and ‘on’ that a switch provides. Lastly the device will be fitted with rubber feet for stability and powered via an AC source as the device will most likely be placed on a shelf of sorts, the necessity for a complicated mounting bracket is unneeded and an AC source removes the need to change batteries over time.
All of the data collected by the device will be viewable through and application on a received device, expected to be some sort of tablet. The application will use a base technology of Java Script as it provides easy access to many open source libraries and functionality. This will all be in an Ionic framework using D3 as our graphics library again, for their open source nature.
The decisions that have been made for the project currently are as follows:
- Sampling: 1kHz, 9 Channels, 2 seconds, 1/hour
- Storage: SD Card
- Wireless: Bluetooth
- Encasing: ABS Plastic
- Sensors: Existing sensors
- Accepting: Mini XLR, BNC Connectors
- Processing: Raspberry Pi
- Display: LED
- Mount: Rubber feet
- Power: AC power
- Receiver: Tablet
- Base Tech: Java Script (through HTML 5 or Native)
- Framework: Ionic
- Graphics: D3
Prototyping, Engineering Analysis, Simulation
Drawings, Schematics, Flow Charts, Simulations
The two circuits below are voltage dividers that will scale the inputs from the connectors for acceleration and pressure to an appropriate voltage for the Analog to Digital Converter to make an accurate conversion without frying the chip. The fist circuit is for the acceleration, which takes the -/+10V input form the three sensors and scales them to to 0-3.3V output. The second does the same with the -/+5V input from the pressure sensors to a 0-3.3V output. This allows the ACD to read the inputs on the same scale as the voltage used to power the chip and make an accurate conversion.
Amplifiers/Voltage DividersThe circuit below represents a low pass filter with a 500Hz cut-off frequency.
Bill of Material (BOM)
Design and Flowcharts
Design Review Materials
Plans for next phase
Plans for semester end:
- Upon completion of the phase review, address final concerns
- Prepare final presentation for Gate Review
- Test Plans
Plans for MSD II:
- Verify the completion of all MSD I phases and that they are properly updated
- Properly document all remaining progress to ensure smooth transitioning
- Construct a WBS for next semester