Project

# Title Team Members TA Documents Sponsor
9 Ant Weight 3-D Printed BattleBot
John Tian
Mig Umnakkittikul
Yanhao Yang
 Gayatri Chandran design_document1.pdf
proposal1.pdf
# Ant Weight 3D Printed BattleBot Competition
Team Members

Yanhao Yang (yanhaoy2)

Yunhan Tian (yunhant2)

Mig Umnakkittikul (sirapop3)

# Problem

We will design a 3-D printed BattleBot to attend the competition instructed by Professor Gruev. To attend the competition, we will need to meet the following requirements:

- BattleBot must be under 2 lbs.
- BattleBot must be made only of these materials: PET, PETG, ABS, or PLA/PLA+.
- BattleBot must be controlled by PC via Bluetooth or Wi-Fi.
- BattleBot must have a custom PCB that will hold a microprocessor, Bluetooth or Wi-Fi receiver, and H-bridge for motor control.
- BattleBot must have a fighting tool activated by a motor.
- BattleBot must have an easy manual shutdown and automatic shutdown with no RF link.
- BattleBot will adhere to the rules on the NRC website.

Our overall goal is to design, code, and build a war robot capable of thriving in the robot battle competition.

# Solution

We will build a 2-lb, 3-D printed BattleBot with a front-hinged lifting wedge (shovel) as the weapon to flip and destabilize other robots. The main structure will be ABS for toughness, PLA for non-critical connectors, and PETG around the power system and microcontroller for heat resistance. Control is via PC over Wi-Fi or Bluetooth using an ESP32 microcontroller.The bot will have at least three motors:Two DC-powered motors to control the robot's wheels for mobility. One geared lifter motor for the shovel, controlled through H-bridge drivers.

# Solution Components

## Microprocessor

We will use the ESP32-S3-WROOM-1-N16 for our BattleBot because it combines built-in Wi-Fi and Bluetooth, eliminating the need for separate modules. Its dual-core processor and ample RAM/flash provide sufficient power to handle motor control, PWM generation, weapon actuation, and sensor processing simultaneously. Its weight (6.5 g) is ideal for a 2-lb bot, and it supports many peripherals.

## Attack Mechanism

To attack, destabilize, and flip opponent bots, we will use a front-hinged lifting wedge (“shovel”) as our primary weapon. The wedge will be 3-D printed with PETG for impact resistance, reinforced at hinge and linkage points to withstand stress. It will span about 50–70% of the bot’s width and feature a low, angled tip to slide under opponents effectively. A small, geared lifter motor will actuate the wedge through a lever linkage, which amplifies the torque from the motor to lift a 2-lb target.

## Mobility System

We will use four small wheels (2.25’’), with the two rear wheels powered by high-torque 600 RPM, 12V DC motors. The smaller wheels lower the ride height of the bot, giving it a lower center of gravity, which improves stability during combat and reduces the chance of being flipped, while still providing solid ground traction. The motors strike a good balance between speed and torque, offering sufficient pushing power to maneuver our heavily armored bot effectively.

## Power System

We will use Lithium Polymer (LiPo) batteries, 4S 14.8V 750 mAh, as the higher voltage may be required for the weaponry. LiPo batteries are significantly lighter than NiCd, provide more power, and save space.

Additionally, we will integrate a motor current sensor (e.g., INA219 or ACS712) into the motor driver circuits to monitor current draw. The ESP32 will read these values in real-time, allowing us to detect stalling conditions and activate manual/automatic shutdown to protect motors and electronics.

## Bot Structure Materials

We will use ABS for the main bot structure, as it offers sufficient strength and a good balance between durability and printability. PLA will be used for general-purpose parts, such as inner connection pieces, where high strength is not required. Finally, PETG will be used around the power system and microprocessor to provide additional heat resistance.

# Criterion for Success

The project will be considered successful if:

- The BattleBot can be fully controlled remotely by PC, including movement and wedge activation.
- The wedge lifter and drive motors operate reliably, capable of destabilizing or flipping a 2-lb opponent.
- Manual and automatic shutdowns function correctly, independent of wireless communication.

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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