Project

# Title Team Members TA Documents Sponsor
44 Voice-Activated Geographic Reference Globe
Mahathi Jayaraman
Rijul Roy
Varsha Mullangi
Team Members:
Mahathi Jayaraman (mj45)
Rijul Roy (rijulr2)
Varsha Mullangi (varsham3)

Problem
Many kids these days, especially American kids, don’t know their geography that well. In addition, many kids are spending a lot of time on screens and online, which is taking them out of the real world. We want to create a solution where kids can learn geography in a manner that does not need them to be connected to the internet or on a screen. This solution should be able to be used in classrooms for kids to learn from, as well as be able to rotate to accommodate the shorter height of kids.

Solution
Our proposed solution is to build a globe that is screen-free and interactive. Rather than manually rotating a globe and having to search for where a certain country is, kids can now simply push a button to activate a microphone and say a country name out loud. The globe will rotate automatically to a designated front marker of the globe and light up the specified countries with LEDs. This will help kids feel more engaged with learning.

Solution Components

Subsystem 1: Speech Recognition with a Push to Talk Mechanism

This subsystem will implement the speech recognition mechanism of the globe. A simple push button and microphone will be used, connected to the GPIO pins of the ESP32-S3 MCU. While the button is pressed, the microphone will collect audio from the user, capturing the specified country the user wants to find. The MCU uses this audio to run an offline, on-device speech recognition software (ESP-SR) to determine which country the user wants to find, which will be used to handle the motor control logic and LEDs.

Components:
ESP32-S3 MCU and ESP-SR Package
I2S Digital Microphone (INMP441)






Subsystem 2: Software-Driven Motor Control

This subsystem controls how the globe physically rotates to face the input country. A low speed DC gear motor will be driven by the ESP32-S3 through a motor driver, allowing the MCU to control both the direction and speed of rotation on the axis. A separate motor will be used to tilt the globe up and down, with the globe sitting in a ring with a ball bearing track. Based on the target country’s stored position and the current angle of the globe, the software will calculate the direction of rotation and the number of turns needed for the globe to rotate to align the country with the front marker. Feedback from a magnetic angle sensor will be used to track the globe’s position and stop rotation at the correct point. This makes the rotation more reliable and prevents the globe from rotating too far past the target.

Components:
22 RPM 24 Volt DC Globe Inline Gearmotor [500635]


Subsystem 3: LED Outline/Markers

This subsystem is responsible for the physical identification of countries using LEDs. We will use a LED grid placed behind the globe, ensuring that that LEDS line the borders and corners of countries. If its a smaller country, making it harder to border, we will use the center point of the country, lighting up only one LED to indicate the location of that country. Since we will be using addressable LEDs, we will be able to assign LEDS to countries, so that when a country is chosen, the logic can quickly determine which LEDS to turn on. We will also use one LED near the button that captures audio, helping the user know when audio is being recorded.

Components:
LED strips (WS2812B)


Subsystem 4: Front Marker Reference
This subsystem is responsible for rotating the globe to face a designed front marker. This marker will be a point on a ring around the globe. This will designate where the user of this globe will be positioned, so that when the globe rotates to allow the country to face this marker, the country will also be facing the user. The globe will also rotate on multiple axes to face this, which can help accommodate the shorter height of kids by making the globe rotate down to make areas near the north pole (such as Iceland or the North Pole) visible to kids who may not be tall enough to see the top of the globe. Every time a country is detected through the microphone, that country will automatically rotate to this marker. The slip ring will be used to ensure that the internal components do not get caught in each other as the globe rotates, and the limit switches will make sure the globe does not rotate too much in any direction.

Components:
ESP32-S3 MCU (controller)
Adafruit AS5600 Magnetic Angle Sensor - rotation position sensor
Slip Ring (because it is a rotating system)
Optional Limit Switches to prevent overrotation
The Motor System (subsystem 2)


Criteria for Success:
The system can use the microphone to accurately identify spoken words, and check if the word is in the database of country names.
When a country name is spoken, the system can light up the country on the globe.
When a country name is spoken, the globe can rotate to display the lit country in front of the user.
When the word “reset” is provided as an input, the globe moves back to its default position and all LEDs are turned off.
The globe will correctly detect the spoken country name and rotate automatically so the specified country is facing the front marker

Monitor for Dough and Sourdough Starter

Jake Hayes, Abhitya Krishnaraj, Alec Thompson

Monitor for Dough and Sourdough Starter

Featured Project

Team Members:

- Jake Hayes (jhayes)

- Abhitya Krishnaraj (abhitya2)

- Alec Thompson (alect3)

# Problem

Making bread at home, especially sourdough, has become very popular because it is an affordable way to get fresh-baked bread that's free of preservatives and other ingredients that many people are not comfortable with. Sourdough also has other health benefits such as a lower glycemic index and greater bioavailability of nutrients.

However, the bulk fermentation process (letting the dough rise) can be tricky and requires a lot of attention, which leads to many people giving up on making sourdough. Ideally, the dough should be kept at around 80 degrees F, which is warmer than most people keep their homes, so many people try to find a warm place in their home such as in an oven with a light on; but it's hard to know if the dough is kept at a good temperature. Other steps need to be taken when the dough has risen enough, but rise time varies greatly, so you can't just set a timer; and if you wait too long the dough can start to shrink again. In the case of activating dehydrated sourdough starter, this rise and fall is normal and must happen several times; and its peak volume is what tells you when it's ready to use.

# Solution

Our solution is to design a device with a distance sensor (probably ultrasonic) and a temperature sensor that can be attached to the underside of most types of lids, probably with magnets. The sensors would be controlled with a microcontroller; and a display (probably LCD) would show the minimum, current, and maximum heights of the dough along with the temperature. This way the user can see at a glance how much the dough has risen, whether it has already peaked and started to shrink, and whether the temperature is acceptable or not. There is no need to remove it from its warm place and uncover it, introducing cold air; and there is no need to puncture it to measure its height or use some other awkward method.

The device would require a PCB, microcontroller, sensors, display, and maybe some type of wireless communication. Other features could be added, such as an audible alarm or a graph of dough height and/or temperature over time.

# Solution Components

## Height and Temperature Sensors

Sensors would be placed on the part of the device that attaches to the underside of a lid. A temperature sensor would measure the ambient temperature near the dough to ensure the dough is kept at an acceptable temperature. A proximity sensor or sensors would first measure the height of the container, then begin measuring the height of the dough periodically. If we can achieve acceptable accuracy with one distance sensor, that would be ideal; otherwise we could use 2-4 sensors.

Possible temperature sensor: [Texas Instruments LM61BIZ/LFT3](https://www.digikey.com/en/products/detail/texas-instruments/LM61BIZ%252FLFT3/12324753)

Proximity sensors could be ultrasonic, infrared LED, or VCSEL.\

Ultrasonic: [Adafruit ULTRASONIC SENSOR SONAR DISTANCE 3942](https://www.digikey.com/en/products/detail/adafruit-industries-llc/3942/9658069)\

IR LED: [Vishay VCNL3020-GS18](https://www.mouser.com/ProductDetail/Vishay-Semiconductors/VCNL3020-GS18?qs=5csRq1wdUj612SFHAvx1XQ%3D%3D)\

VCSEL: [Vishay VCNL36826S](https://www.mouser.com/ProductDetail/Vishay-Semiconductors/VCNL36826S?qs=d0WKAl%252BL4KbhexPI0ncp8A%3D%3D)

## MCU

An MCU reads data from the sensors and displays it in an easily understandable format on the LCD display. It also reads input from the user interface and adjusts the operation and/or output accordingly. For example, when the user presses the button to reset the minimum dough height, the MCU sends a signal to the proximity sensor to measure the distance, then the MCU reads the data, calculates the height, and makes the display show it as the minimum height.

Possible MCU: [STM32F303K8T6TR](https://www.mouser.com/ProductDetail/STMicroelectronics/STM32F303K8T6TR?qs=sPbYRqrBIVk%252Bs3Q4t9a02w%3D%3D)

## Digital Display

- A [4x16 Character LCD](https://newhavendisplay.com/4x16-character-lcd-stn-blue-display-with-white-side-backlight/) would attach to the top of the lid and display the lowest height, current height, maximum height, and temperature.

## User Interface

The UI would attach to the top of the lid and consist of a number of simple switches and push buttons to control the device. For example, a switch to turn the device on and off, a button to measure the height of the container, a button to reset the minimum dough height, etc.

Possible switch: [E-Switch RA1113112R](https://www.digikey.com/en/products/detail/e-switch/RA1113112R/3778055)\

Possible button: [CUI Devices TS02-66-50-BK-160-LCR-D](https://www.digikey.com/en/products/detail/cui-devices/TS02-66-50-BK-160-LCR-D/15634352)

## Power

- Rechargeable Lithium Ion battery capable of staying on for a few rounds of dough ([2000 mAh](https://www.microcenter.com/product/503621/Lithium_Ion_Battery_-_37v_2000mAh) or more) along with a USB charging port and the necessary circuitry to charge the battery. The two halves of the device (top and underside of lid) would probably be wired together to share power and send and receive data.

## (stretch goal) Wireless Notification System

- Push notifications to a user’s phone whenever the dough has peaked. This would likely be an add-on achieved with a Raspberry Pi Zero, Gotify, and Tailscale.

# Criterion For Success

- Charge the battery and operate on battery power for at least 10 hours, but ideally a few days for wider use cases and convenience.

- Accurately read (within a centimeter) and store distance values, convert distance to dough height, and display the minimum, maximum, and current height values on a display.

- Accurately read and report the temperature to the display.

- (stretch goal) Inform the user when the dough has peaked (visual, audio, or app based).

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