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Chaitanya’s Status Report for March 8

This week, I focused on getting the PCB layout off the ground. My first obstacle was finding the proper layout footprint in a PCB design tool. My familiarity with Autodesk Fusion360 led me to look into finding a footprint in the Fusion360 library. After conducting extensive research in the Fusion360 library and looking for download options online, I concluded there were no options to proceed with Fusion360. I looked into alternatives and settled with using KiCad for my layout tool as the Daisy footprint was uploaded to the open source library in KiCad. I have attached a screenshot of the print below.

I then looked into the standard sizing of guitar pedal casing to determine the size of the board. After conducting brief research, I decided to size my board with a width of 2.85” and a height of 5”. I have defined the board outlines in my layout. In addition, I contributed to the design requirements and system implementation portions of the design report, amongst other minor formatting contributions. As part of the report, we finalized an initial draft of the bill of materials. While further discussion is needed to determine if any more components are required for our product, this initial list allowed me to begin my search for layout footprints of materials in the KiCad library and online. My next goal is to use the pinout of the Daisy Seed to begin connecting the I/O pins and power pins to the appropriate components.

I am still on schedule as the barebones of the PCB are coming together. I hope to have a board layout next week. I also want to begin prototyping my components on a breadboard. However, this might temporarily be on hold until I can determine basic tests to prototype as waiting for full functionality of our desired features will take too long and limit the duration of time for which I can prototype.

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Chaitanya’s Status Report for February 22

This week, I focused on ironing out exactly which models of components we need for our user interface. I researched switches, buttons, 7-segment displays, etc. and made a list for ordering. I also finalized the overall implementation plan involving the daisy seed and its interaction with i/o devices. I presented our design on Wednesday in class and answered questions as well. I began working on the PCB schematic/layout, finding the exact model of the Daisy Seed Microcontroller and other hardware components of our pedal interface. I have began to wire periphery based on pinout and desired function. I have not started prototyping, but I will do that once a PCB layout is somewhat finalized to make efficient use of time.

While I have made some progress, I am slowly starting to fall behind. I have been dedicating a lot of time to documentation (design presentation). However, in doing so, I have lost track of the actual project progress. My plan to get back on track involves dedicating some time over break to get a preliminary draft of the PCB done to show to group members, professor, and TA for feedback. Then, the following week or so can be allotted to finalizing the layout and sending for manufacturing.

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Chaitanya’s Status Report for February 15

Professor Sullivan and Gordan (TA) noted that our MVP lacked some details. Hence, my first priority was to iron out our MVP. I did this early in the week after meeting with my group, noting the following details in a Google Doc:

Input:

  • Sequence of notes played
  • Time shift (delay) specified by knob
  • Amplitude Modulation specified by knob 
  • Specify beat – 1, 2, 3, 4 

Output:

  • Sequence of notes delayed by specified time shift + indefinite amplitude modulation
  • Notes will be played based on beat specified 

Stretch Goals

  • Pitch Shifting – user specifies number of octaves 
  • Tap Tempo – specify delay based on how user taps guitar pedal
  • LED Buttons

This provided some clarity for the basic and additional functionality of our pedal that will be crucial when answering questions about the design next week. In addition, Nick and I began the brainstorming process for additional hardware functions. Being hardware-focused individuals we want to ensure that our contributions are meaningful and show in the functions of our pedal. We plan to have a list by coming Monday to present to Professor Sullivan during our meeting. The middle of the week involved drawing the diagram for our design, making notes of interface functionality, and specifying a clear user interface to promote maximum usability. The hand-drawn diagram below that I created from our group meeting early in the week will be used next week when explaining design details. I also drew the graph (originally created by Josie) in a clear and easy-to-understand manner to provide a presentable visual for next week’s presentation.

The late parts of this week were dedicated to ironing out further design details, particularly with our PCB. I contributed to our design review presentation that I will be presenting next week.

My progress seems to be on schedule at this point. It was noted that getting our pcb back in a timely manner is not a guarantee. My hope is that our slack provides me ample time to get the board back. However, we will be prototyping using a breadboard and/or a PCB dev board, which will serve as our backup. While this is not ideal as the circuitry will go inside our pedal that is moving up and down when pressed, it will ensure that we can deliver our MVP in the case that we cannot rely in a timely fabrication of our board.

In the next week, I would like to get a jump on the PCB design and finalize the schematic and specific use of the board by next week so that I can get the board to tapeout in a timely manner. I would also like to begin prototyping our board using the daisy seed to get a feel of how our circuitry will look. This will involve further study of the pinout of the daisy seed and relating that to the various design details that we will be finalizing prior to our presentation next week.

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Team Status Report on February 8

Our team worked on finalizing our proposal (slides) and ironing out the schedule for the upcoming weeks. In doing so, we saw that some of the significant risks for our timeline include delays in getting our PCB back from fabrication. In addition, delays in getting our microcontroller and other hardware components could significantly impact our progress. From a design perspective, the PCB, 3D printing, and user interface don’t pose immediate risks. However, our choice of microcontroller (Daisy Seed) could prove to be a risk as none of us have previously used it (in contrast to other microcontrollers like STM32 or Raspberry PI). Our preliminary research indicates that this risk should be minimal, but our contingency plans involve using an FPGA or microcontroller from the school inventory that meets the specs that we desire.

Our decision to go with the Daisy was the only design “change” that we made over the past 1-2 weeks. This “change” was more of a narrowing of our options to a singular implementation. No changes in cost are to be accounted for as purchases have not been made.

The initial schedule was finalized this week. The schedule will be updated as needed in future status reports.

Our group looks to wrap up the research phase of our project and begin making order requests in the next few weeks.

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Chaitanya’s Status Report for February 8

This week, I focused on identifying technical challenges and quantitative and qualitative metrics for testing and verification to incorporate in the project proposal slides. In particular, I identified 4 primary technical challenges: the need for effective analog-to-digital and digital-to-analog converters, picking a microcontroller with sufficient memory storage corresponding to our desired sampling rate and effects, sizing our pedal appropriately, and creating an easy-to-use user interface. I also identified the need for testing equipment such as an oscilloscope and simulation software to measure quantitative aspects of our input and output signals to verify functionality and the usage of qualitative feedback from experienced musicians to ensure that our pedal satisfies potential users of our product. In addition to detailing the above parts of our proposal presentation, I began researching ADC and DAC options online and within the Autodesk Fusion360 libraries, keeping the context of our project in mind.  I am taking on hardware/PCB responsibilities for our project, so I looked into the PCB design process, namely the tapeout process and the rough timeline for the fabrication process. This was then incorporated into our Gantt chart. Finally, I looked into the specs of the Daisy microcontroller and conducted a preliminary inspection of its features to ensure that it meets the needs of our project (at least for now).

Most of my work for this past week was planning-related and there were not any tangible deliverables. Hence, my progress is on schedule.

Over the next week, I hope to be able to finalize all hardware components needed for our project. This includes any user interface LCD screens, knobs on the pedal, and PCB details. I would also like to begin working on the PCB schematics. I will continue to look into the Daisy microcontroller functionality, though that will primarily be handled by Josie.