Project

# Title Team Members TA Documents Sponsor
4 Instant Nitro Cold Brew Machine
Most Commercially Promising Project
Danis Heto
Mihir Vardhan
design_document1.pdf
final_paper1.pdf
other1.zip
photo1.png
photo2.png
presentation1.pdf
proposal1.pdf
video
# Instant Nitro Cold Brew Machine

Team Members:
- Mihir Vardhan (mihirv2)
- Danis Heto (dheto3)

# Problem
Cold brew is made by steeping coffee grounds in cold water for 12-18 hours. This low-temperature steeping extracts fewer bitter compounds than traditional hot brewing, leading to a more balanced and sweeter flavor. While cold brew can be prepared in big batches ahead of time and stored for consumption throughout the week, this would make it impossible for someone to choose the specific coffee beans they desire for that very morning. The proposed machine will be able to brew coffee in cold water in minutes by leveraging air pressure. The machine will also bring the fine-tuning and control of brewing parameters currently seen in hot brewing to cold brewing.

# Solution
The brew will take place in an airtight aluminum chamber with a removable lid. The user can drop a tea-bag like pouch of coffee grounds into the chamber along with cold water. By pulling a vacuum in this chamber, the boiling point of water will reach room temperature and allow the coffee extraction to happen at the same rate as hot brewing, but at room temperature. Next, instead of bringing the chamber pressure back to atmospheric with ambient air, nitrogen can be introduced from an attached tank, allowing the gas to dissolve in the coffee rapidly. The introduction of nitrogen will prevent the coffee from oxidizing, and allow it to remain fresh indefinitely. When the user is ready to dispense, the nitrogen pressure will be raised to 30 PSI and the instant nitro cold brew can now be poured from a spout at the bottom of the chamber.

The coffee bag prevents the coffee grounds from making it into the drink and allows the user to remove and replace it with a bag full of different grounds for the next round of brewing, just like a Keurig for hot coffee.

To keep this project feasible and achievable in one semester, the nitrogenation process is a reach goal that we will only implement if time allows. Since the vacuum and nitrogenation phases are independent, they can both take place through the same port in the brewing chamber. The only hardware change would be an extra solenoid control MOSFET on the PCB.

We have spoken to Gregg in the machine shop and he believes this vacuum chamber design is feasible.

# Solution Components
## Brewing Chamber
A roughly 160mm tall and 170mm wide aluminum chamber with 7mm thick walls. This chamber will contain the brew water and coffee grounds and will reach the user-set vacuum level and nitrogenation pressure if time allows. There will be a manually operated ball valve spout at the bottom of this chamber to dispense the cold brew once it is ready. The fittings for the vacuum hose and pressure sensor will be attached to the screw top lid of this chamber, allowing the chamber to be removed to add the water and coffee grounds. This also allows the chamber to be cleaned thoroughly.

## Temperature and Pressure Sensors
A pressure sensor will be threaded into the lid of the brewing chamber. Monitoring the readings from this pressure sensor will allow us to turn off the vacuum pump once the chamber reaches the user-set vacuum level. A temperature thermocouple will be attached to the side of the brewing chamber. The temperature measured will be displayed on the LCD display. This thermocouple will be attached using removable JST connectors so that the chamber can be removed entirely from the machine for cleaning.

## Vacuum Pump and Solenoid Valve
An oilless vacuum pump will be used to pull the vacuum in the brewing chamber. A solenoid valve will close off the connection to this vacuum pump once the user-set vacuum pressure is reached and the pump is turned off. To stay within the $100 budget for this project, we have been given a 2-Stage 50L/m Oil Free Lab Vacuum Pump on loan for this semester. The pump will connect to the chamber through standard PTFE tubing and push-fit connectors

If time allows and we are able to borrow a nitrogen tank, an additional solenoid and a PTFE Y-connector would allow the nitrogen tank to connect to the vacuum chamber through the same port as the vacuum pump.

## LCD Display and Rotary Encoder
The LCD display allows the user to interact with the temperature and pressure components of the brewing chamber. This display will be controlled using a rotary encoder with a push button. The menu style interface will allow you to control the vacuum level and brew time in the chamber, along with the nitrogenation pressure if time allows. The display will also monitor the temperature of the chamber and display it along with the time remaining and the current vacuum level.


# Criterion For Success

- A successful cold brew machine would be able to make cold brew coffee at or below room temperature in ten minutes at most.
- The machine must also allow the user to manually control the brew time and vacuum level as well as display the brew temperature.
- The machine must detect and report faults. If it is unable to reach the desired vacuum pressure or is inexplicably losing pressure, the machine must enter a safe ‘stop state’ and display a human readable error code.
- The reach goal for this project, not a criterion for success, would be the successful nitrogenation of the cold brew.

BusPlan

Aashish Kapur, Connor Lake, Scott Liu

BusPlan

Featured Project

# People

Scott Liu - sliu125

Connor Lake - crlake2

Aashish Kapur - askapur2

# Problem

Buses are scheduled inefficiently. Traditionally buses are scheduled in 10-30 minute intervals with no regard the the actual load of people at any given stop at a given time. This results in some buses being packed, and others empty.

# Solution Overview

Introducing the _BusPlan_: A network of smart detectors that actively survey the amount of people waiting at a bus stop to determine the ideal amount of buses at any given time and location.

To technically achieve this, the device will use a wifi chip to listen for probe requests from nearby wifi-devices (we assume to be closely correlated with the number of people). It will use a radio chip to mesh network with other nearby devices at other bus stops. For power the device will use a solar cell and Li-Ion battery.

With the existing mesh network, we also are considering hosting wifi at each deployed location. This might include media, advertisements, localized wifi (restricted to bus stops), weather forecasts, and much more.

# Solution Components

## Wifi Chip

- esp8266 to wake periodically and listen for wifi probe requests.

## Radio chip

- NRF24L01 chip to connect to nearby devices and send/receive data.

## Microcontroller

- Microcontroller (Atmel atmega328) to control the RF chip and the wifi chip. It also manages the caching and sending of data. After further research we may not need this microcontroller. We will attempt to use just the ens86606 chip and if we cannot successfully use the SPI interface, we will use the atmega as a middleman.

## Power Subsystem

- Solar panel that will convert solar power to electrical power

- Power regulator chip in charge of taking the power from the solar panel and charging a small battery with it

- Small Li-Ion battery to act as a buffer for shady moments and rainy days

## Software and Server

- Backend api to receive and store data in mongodb or mysql database

- Data visualization frontend

- Machine learning predictions (using LSTM model)

# Criteria for Success

- Successfully collect an accurate measurement of number of people at bus stops

- Use data to determine optimized bus deployment schedules.

- Use data to provide useful visualizations.

# Ethics and Safety

It is important to take into consideration the privacy aspect of users when collecting unique device tokens. We will make sure to follow the existing ethics guidelines established by IEEE and ACM.

There are several potential issues that might arise under very specific conditions: High temperature and harsh environment factors may make the Li-Ion batteries explode. Rainy or moist environments may lead to short-circuiting of the device.

We plan to address all these issues upon our project proposal.

# Competitors

https://www.accuware.com/products/locate-wifi-devices/

Accuware currently has a device that helps locate wifi devices. However our devices will be tailored for bus stops and the data will be formatted in a the most productive ways from the perspective of bus companies.