Project

# Title Team Members TA Documents Sponsor
42 Autonomous Cold Salad Bar
 Siddhaarta Venkatesh
Tejas Alagiri Kannan
Tinhsu Wen
 Aniket Chatterjee design_document1.pdf
final_paper1.pdf
photo1.png
photo2.png
presentation1.pdf
proposal1.jpeg
proposal2.pdf
video
# **Team:**

1. Tejas Alagiri Kannan(tejasa4)
2. Siddhaarta Venkatesh(sv39)

# **Problem:**
In the food industry, a huge number of processes are extremely rote and utilize manpower on monotonic tasks that can be replaced by an autonomous system. One such problem is the usage of manpower in assembly line format restaurants(eg, Chipotle, Forage Kitchen, Qdoba, etc.). Just as in the automation industry, where the assembly line is, in essence, replaced by 6-DoF arms and robot operators, I believe the manpower in restaurants can also be replaced by a robotic system that can provide higher efficiency. We have already seen a large number of processes getting automated in the restaurant industry, such as the automated food bar in sushi restaurants and robotic servers(not widely adapted unfortunately).

# **Solution:**
At the outset, I would like to mention that the solution does not aim to automate the entire pipeline from creating the dish to serving it. To perform highly technical dishes is a different problem in itself. I aim to make the serving process more efficient and reduce wait time. Given the ingredients, such as, chopped chicken, chopped onions, sauces, etc(which i believe is a fair starting point)

Each ingredient will have its own pipe that dispenses one specific type of dish. Once we receive instructions of what food needs to be prepared and the x # of ingredients it needs to dispense and in which order, the bowl on a conveyor belt will move back and forth to fill up with those ingredients. These ingredients are funneled from their own pipes that dispenses the ingredients, one at a time. The final box is then sealed and placed in a shaker which mixes the ingredients and it is served at the end.

# **COMPONENTS:**

# **Subsystem 1: Motion**
The bowl must be moved around the pipes to get filled. This is what we propose:

Conveyor belt: 4 idlers, 2 head pulleys, 1 NEMA 23 motor(or other), 1 gear reducer, 1 motor driver(TB6600)

1 Food storage basket, 5 individual dispensary pipes, 5 servo motors, 1 servo motor PWM controller

The dispensary pipes will be pumping out food using a servo pump filler mechanism where the servo motor will push down on the contents of the pump(in a piston like motion) and squeeze out the food). We will use the ESP32 Microcontroller series

# **Subsystem 2: User Interface**
For initial testing, simple buttons to determine which dish is chosen. The final device will involve a screen, natural interface. The simple buttons will just be regular tactile buttons. and the final screen would be an ST7789 LCD display that will show the user what food has been ordered. It will show the user what options they have chosen for their salad and how to add/remove particular items with a button press

# **Subsystem 3: Food presentation**
We expect to have the final salad, well tossed and provided to the user. So once the bowl is filled which is determined by it passing through the pipes of all its ingredients, the user will close it with a cap. the user will have the choice to have it shaked or not. That feature is an additional button after the food is dispensed. The bowl is then placed in a closed contrapment which simply rotates at high speeds to mix the food. It is a very similar design to regular boba shakers.
Shaker: 1 NEMA 23 motor, 1 gear box, 1 motor driver(TB6600)

# **Subsystem 4: Accuracy checking**
A major part of this project is to ensure efficiency. So we will incorporate a weight sensor(mini load cell), this weight sensor will track the weight of the bowl as items are being dispensed and will serve as a checker to stop the machine from over dispensing.

# **Subsystem 5: Power system**
For demonstration purposes the machine will be hooked up to a benchtop powersupply or another reliable form of powersupply similar to a benchtop like a low-grade DC power supply.

Another main component that we will add is food safe tubing to ensure that the food does not get contaminated

# **Criterions for success:**
1. The conveyor belt is able to move consistently in a way that the bowl is under the right dispenser.
2. Each dispenser is able to dispense food. This would be for both solid and liquid food, such as sauces.
3. Each dispenser is able to dispense the right amount of food or a range of food in a set range.
4. Initial prototype can, on button press, determine exact motor angles to move the components for early demo during semester
5. Final prototype can, on user request, send a signal to the microprocessor to move bowl and dispense mock food into a bowl.

# **Team work requirements:**

1. CAD every individual component in a miniature form to depict the real system (1 week)
2. Use Dev board with motor drivers to demonstrate bread board working of Criterion 1 of success. (1 week)
3. Attach devboard solution to CAD physical model to take into account motor backlash and other physical constraints like power supply issues and overheating ( 1 week)
4. Start PCB design based on the chosen direction. Soldering and debugging (3-4 weeks)
5. Final assembly and testing( 1 week)
This gives us maybe 1 week of extra leeway for any hindrances.

Tesla Coil Guitar Amp

David Mengel, Griffin Rzonca

Featured Project

# Tesla Coil Guitar Amp

Team Members:

* Griffin Rzonca (grzonca2)

* David Mengel (dmengel3)

# Problem:

Musicians are known for their affinity for flashy and creative displays and playing styles, especially during their live performances. One of the best ways to foster this creativity and allow artists to express themselves is a new type of amp that is both visually stunning and sonically interesting.

# Solution:

We propose a guitar amp that uses a Tesla coil to create a unique tone and dazzling visuals to go along with it. The amp will take the input from an electric guitar and use this to change the frequency of a tesla coil's sparks onto a grounding rod, creating a tone that matches that of the guitar.

# Solution Components:

## Audio Input and Frequency Processing -

This will convert the output of the guitar into a square wave to be fed as a driver for the tesla coil. This can be done using a network of op-amps. We will also use an LED and phototransistor to separate the user from the rest of the circuit, so that they have no direct connection to any high voltage circuitry. In order to operate our tesla coil, we need to drive it at its resonant frequency. Initial calculations and research have this value somewhere around 100kHz. The ESP32 microcontroller can create up to 40MHz, so we will use this to drive our circuit. In order to output different notes, we will use pulses of the resonant frequency, with the pulses at the frequency of the desired note.

## Solid-state switching -

We will use semiconductor switching rather than the comparably popular air-gap switching, as this poses less of a safety issue and is more reliable and modifiable. We will use a microcontroller, an ESP 32, to control an IR2110 gate driver IC and two to four IGBTs held high or low in order to complete the circuit as the coil triggers, acting in place of the air gap switch. These can all be included on our PCB.

## Power Supply -

We will use a 120V AC input to power the tesla coil and most likely a neon sign transformer if needed to step up the voltage to power our coil.

## Tesla Coil -

Consists of a few wire loops on the primary side and a 100-turn coil of copper wire in order to step up voltage for spark generation. Will also require a toroidal loop of PVC wrapped in aluminum foil in order to properly shape the electric field for optimal arcing. These pieces can be modular for easy storage and transport.

## Grounding rod -

All sparks will be directed onto a grounded metal rod 3-5cm from the coil. The rest of the circuit will use a separate neutral to further protect against damage. If underground cable concerns exist, we can call an Ameren inspector when we test the coil to mark any buried cables to ensure our grounding rod is placed in a safe location.

## Safety -

Tesla coils have been built for senior design in the past, and as noted by TAs, there are several safety precautions needed for this project to work. We reviewed guidelines from dozens of recorded tesla coil builds and determined the following precautions:

* The tesla coil will never be turned on indoors, it will be tested outside with multiple group members present using an outdoor wall outlet, with cones to create a circle of safety to keep bystanders away.

* We will keep everyone at least 10ft away while the coil is active.

* The voltage can reach up to 100kV (albeit low current) so all sparks will be directed onto a grounding rod 3-5cm away, as a general rule of thumb is each 30kV can bridge a 1cm gap.

* The power supply (120-240V) components will be built and tested in the power electronics lab.

* The coil will have an emergency stop button and a fuse at the power supply.

* The cable from the guitar will use a phototransistor so that the user is not connected to a circuit with any power electronics.

# Criterion for Success:

To consider this project successful, we would like to see:

* No safety violations or injuries.

* A tesla coil that produces small visible and audible 3-5cm sparks to our ground rod.

* The coil can play several different notes and tones.

* The coil can take input from the guitar and will play the corresponding notes.

Project Videos