Lab Notebook

Video, Slides

Keeping a professional record of your design work is a requirement of the course. If maintained properly, lab notebooks serve as an official and legal record of the development of the intellectual property related to your project. It also serves as a way to document and track changes to your design, results of all tests performed, and the effort you have put into your project. A well-kept notebook will simplify writing of all required documentation for this course (design review, final paper, etc) as all of the information in those documents should already exist in your notebook. Finally, keeping a notebook is simply good engineering practice and likely will be required by future employers, so it is a good idea to get in the habit of maintaining one now.

The Book

Any notebook with permanent bindings designed for laboratory record keeping is acceptable. Notebooks should have pre-numbered pages and square grids on their pages. We will not accept normal spiral-bound notebooks, as these are not permissible in court since pages can be easily replaced. While most of you probably won't be taking your design to court, we want to teach you to get into the habit of keeping legally acceptable records. Some of you may decide you do want to patent your project, so it will be very beneficial to have given yourself the legal advantage from the start.

Electronic Notebook

Alternatively, lab notebooks may be kept digitally as Markdown documents in a Git repo on Github or Gitlab, as in the example below. See a complete example of a 445 Git repo here.

notebooks/
├── alex/
│   ├── README.md
│   └── an_image.png
├── pouya/
│   └── README.md
└── nick/
    ├── README.md
    └── another_image.png
	

Notebook entries:

Each complete entry should include:

  1. Date
  2. Brief statement of objectives for that session
  3. Record of what was done

The record will include equations, diagrams, and figures. These should be numbered for reference in the narrative portion of the book. Written entries and equations should appear on the right-hand page of each pair. Drawn figures, diagrams, and photocopies extracted from published sources should be placed on the left-hand side, which is graph-ruled. All separate documents should be permanently attached to the notebook. All hand-written entries must be made in pen.

Overall, the book should contain a record that is clear and complete, so that someone else can follow progress, understand problems, and understand decisions that were made in designing and executing the project.

What to include:

There is always something to record:

Suppose you are only "kicking around" design ideas for the project with someone, or scanning library sources. Your objective is what you're hoping to find. The record shows what you found or what you decided and why, even if it isn't final.

One of the most common errors is to fail to record these seemingly "unimportant" activities. Down the road, they may prove crucial in understanding when and where a particular idea came from.

Submission and Deadlines

Lab notebooks must be submitted at lab checkout on Reading Day. If you are unable to attend lab checkout, please make arrangements with your TA ahead of time.

Musical Hand

Ramsey Foote, Thomas MacDonald, Michelle Zhang

Musical Hand

Featured Project

# Musical Hand

Team Members:

- Ramesey Foote (rgfoote2)

- Michelle Zhang (mz32)

- Thomas MacDonald (tcm5)

# Problem

Musical instruments come in all shapes and sizes; however, transporting instruments often involves bulky and heavy cases. Not only can transporting instruments be a hassle, but the initial purchase and maintenance of an instrument can be very expensive. We would like to solve this problem by creating an instrument that is lightweight, compact, and low maintenance.

# Solution

Our project involves a wearable system on the chest and both hands. The left hand will be used to dictate the pitches of three “strings” using relative angles between the palm and fingers. For example, from a flat horizontal hand a small dip in one finger is associated with a low frequency. A greater dip corresponds to a higher frequency pitch. The right hand will modulate the generated sound by adding effects such as vibrato through lateral motion. Finally, the brains of the project will be the central unit, a wearable, chest-mounted subsystem responsible for the audio synthesis and output.

Our solution would provide an instrument that is lightweight and easy to transport. We will be utilizing accelerometers instead of flex sensors to limit wear and tear, which would solve the issue of expensive maintenance typical of more physical synthesis methods.

# Solution Components

The overall solution has three subsystems; a right hand, left hand, and a central unit.

## Subsystem 1 - Left Hand

The left hand subsystem will use four digital accelerometers total: three on the fingers and one on the back of the hand. These sensors will be used to determine the angle between the back of the hand and each of the three fingers (ring, middle, and index) being used for synthesis. Each angle will correspond to an analog signal for pitch with a low frequency corresponding to a completely straight finger and a high frequency corresponding to a completely bent finger. To filter out AC noise, bypass capacitors and possibly resistors will be used when sending the accelerometer signals to the central unit.

## Subsystem 2 - Right Hand

The right subsystem will use one accelerometer to determine the broad movement of the hand. This information will be used to determine how much of a vibrato there is in the output sound. This system will need the accelerometer, bypass capacitors (.1uF), and possibly some resistors if they are needed for the communication scheme used (SPI or I2C).

## Subsystem 3 - Central Unit

The central subsystem utilizes data from the gloves to determine and generate the correct audio. To do this, two microcontrollers from the STM32F3 series will be used. The left and right hand subunits will be connected to the central unit through cabling. One of the microcontrollers will receive information from the sensors on both gloves and use it to calculate the correct frequencies. The other microcontroller uses these frequencies to generate the actual audio. The use of two separate microcontrollers allows for the logic to take longer, accounting for slower human response time, while meeting needs for quicker audio updates. At the output, there will be a second order multiple feedback filter. This will get rid of any switching noise while also allowing us to set a gain. This will be done using an LM358 Op amp along with the necessary resistors and capacitors to generate the filter and gain. This output will then go to an audio jack that will go to a speaker. In addition, bypass capacitors, pull up resistors, pull down resistors, and the necessary programming circuits will be implemented on this board.

# Criterion For Success

The minimum viable product will consist of two wearable gloves and a central unit that will be connected together via cords. The user will be able to adjust three separate notes that will be played simultaneously using the left hand, and will be able to apply a sound effect using the right hand. The output audio should be able to be heard audibly from a speaker.

Project Videos