Project

# Title Team Members TA Documents Sponsor
25 Electronic Martial Arts Paddles
Alexander Lee
Liam McBride
Jason Jung design_document1.pdf
final_paper1.pdf
grading_sheet1.pdf
proposal1.pdf
video1.mov
# Title: Electronic Martial Arts Paddles

Team Members:
- Liam McBride (liamjm2)
- Alexander Lee (asl9)

# Problem

Currently there is no good way to accurately quantify performance in Taekwondo training for drills such as speed and power drills. There exists electronic gear for automatic scoring by tracking the power and the location of the martial artists’ kicks, but that gear is only used in competition and is prohibitively expensive.

# Solution

We are proposing electronic target paddles with pressure sensors at different locations of the paddle and LED’s to measure power and speed for kicking during training. We will also facilitate reaction speed/timing drills via sound or blinking of the LEDs. Example paddle here:

[https://www.ctitkd.com/product-page/vision-kicking-target](url)

We would have our main system (pcb) be a separate box that would handle the inputs from the paddles, and connect to a display to show scores and statistics.

# Background


Both Liam and Alex are executives for the university’s RSO Competitive Taekwondo Club, and have practiced Taekwondo for 10+ years, competing at local to international levels.

# Solution Components

## Subsystem 1: Control Box and Display

Explain what the subsystem does. Explicitly list what sensors/components you will use in this subsystem. Include part numbers.

Custom PCB




Bluetooth receiver for connecting with the paddle and sending/receiving data and instructions:
The target paddles will be difficult to maintain if there were wires coming out of it to the PCB, so we will utilize bluetooth connection for the LED and sensors

HDMI Out to regular display or LCD screen:
Have an HDMI connection to a monitor or LCD screen directly from the PCB to display our scores using a health bar mechanism as commonly seen in video games.
We will also display statistics for our drills


Wall power/power supply:
We would need a constant source of power, which we would use a power supply. The power supply will be connected to a wall outlet.

Sound system/speaker (optional):
We will use speakers that play a sound when the target paddle is hit, along with the LED.
We will also use the speakers to give a sound cue for reaction drills
different sounds for different kicks or choosing right or left leg

## Subsystem 2: Electronic Paddle

Pressure/force sensor:
three of these sensors each placed at the front, middle, and rear side of the paddle to distinguish the location of the hits. Each of these sensors will measure how strong the hits were, and crossing a certain force threshold will indicate a valid hit. Since force sensors that handle high forces can be fairly expensive, we would need to come up with a way to dampen the impact or distribute the force, and then scale the measurement so we can use cheaper, lower threshold sensors. We are also considering the use of an accelerometer for a potentially more affordable option.

LEDs or LED strip:
These led strips will be an indicator for a valid hit,
or for reaction drills,
or each led with different colors will indicate which part of the paddle was hit.
Different colors for different kicks or choosing right or left leg

Bluetooth transmitter for connecting with control box


Battery power:
Since the components on the target paddles will be physically separate from the PCB box, we will need battery power to keep the LED and sensors operating without a direct power supply from the wall.



# Criterion For Success

- System is able to accurately track response times
- System is able to accurately measure force of strikes
- Bluetooth is working so we don’t resort to using wires
- Paddle and auxiliary machinery is able to withstand repeated strong blows without breaking. (> 10 strikes min)
- LED, speaker, and sensors are working in cohesion
- Display is accurately reflecting desired results.

CHARM: CHeap Accessible Resilient Mesh for Remote Locations and Disaster Relief

Martin Michalski, Melissa Pai, Trevor Wong

Featured Project

# CHARM: CHeap Accessible Resilient Mesh for Remote Locations and Disaster Relief

Team Members:

- Martin Michalski (martinm6)

- Trevor Wong (txwong2)

- Melissa Pai (mepai2)

# Problem

There are many situations in which it is difficult to access communicative networks. In disaster areas, internet connectivity is critical for communication and organization of rescue efforts. In remote areas, a single internet connection point often does not cover an area large enough to be of practical use for institutions such as schools and large businesses.

# Solution

To solve these problems, we would like to create a set of meshing, cheap, lightweight, and self-contained wireless access points, deployable via drone. After being placed by drone or administrator, these access points form a WiFi network, usable by rescuers, survivors, and civilians. Our network will have QoS features to prioritize network traffic originating from rescuers. Having nodes/access points deployable by drone ensures we are able to establish timely connectivity in areas where search and rescue operations are still unable to reach.

Over the course of the semester, we will produce a couple of prototypes of these network nodes, with built in power management and environmental sensing. We aim to demonstrate our limited network’s mesh capabilities by setting up a mock network on one of the campus quads, and connecting at various locations.

# Solution Components

## Router and Wireless Access Point

Wireless Access for users and traffic routing will be the responsibility of an Omega2 board, with onboard Mediatek MT7688 CPU. For increased signal strength, the board will connect to a RP-SMA antenna via U.FL connector.

The Omega2 will be running OpenWRT, an Linux-based OS for routing devices. We will develop processes for the Omega2 to support our desired QoS features.

## Battery Management System

This module is responsible for charging the lithium-ion battery and ensuring battery health. Specifically, we will ensure the battery management system has the following features:

- Short circuit and overcurrent protection

- Over- and under-voltage protection

- An ADC to provide battery status data to the microcontroller

- 3.3v voltage regulation for the microcontroller and other sensors

In addition to miscellaneous capacitors and resistors, we intend to use the following components to implement the battery management system:

- The MT2492 step-down converter will be used to step down the output voltage of the battery to 3.3 volts. Between the GPS and extra power the microcontroller might consume with an upgraded Wifi antenna, low-dropout regulators would not provide sufficient power in an efficient manner. Instead, we will implement a 2 amp buck converter to improve efficiency and ensure there are no current bottlenecks.

- We will utilize two button-top protected 18650 3400 mAh lithium ion batteries in series to power each node. Placing two of these batteries in series will ensure their combined voltage never falls below the minimum voltage input of the buck converter, and accounting for the buck converter’s inefficiency these batteries should give us about 21 Wh of capacity. The cells we plan on using include a Ricoh R5478N101CD protection IC that provides over-voltage, under-voltage, and over-current protection. Using a standard battery form factor will make them easy to replace in the future as needed.

- A USB-C port with two pulldown resistors will provide 5 volt charging input with up to 3 amps of current, depending on the charger.

- The MT3608 step-up converter will boost the input voltage from the usb-c port and feed it into the charging controller.

- The MCP73844 Charge Management Controller will be used to charge the batteries. This controller supports CC/CV charging and a configurable current limit for safe and effective battery charging.

- The TI ADS1115 ADC will be used for battery voltage monitoring. This chip is used in the official Omega2 expansion board, so it should be easy to integrate in software. We will use a voltage divider to reduce the battery voltage to a range this chip can measure, and this chip will communicate over an I2C bus.

## Sensor Suite

Each node will have a battery voltage sensor and GPS sensor, providing the system with health information for each node. On top of the Wifi-connectivity, each module would have a series of sensors to detect the status of the physical node and helpful environment variables. This sensor suit will have the following features and components to implement it

- Ultimate GPS Module PA1616D will be used for positioning information. This chip utilizes 3.3V which is supplied through our battery management system.

Battery Voltage Monitor

- The TI ADS1115 ADC (mentioned in the BMS section) is for battery voltage monitoring. It interfaces via I2C to the Omega2.

## System Monitor

A system monitor which provides visibility of the overall system status for deployed network nodes. Information that we will show includes: last known location, battery health, and network statistics (e.g. packets per second) from the physical devices.

We plan on using React to provide an intuitive UI, using google-map-react and other React packages to create an interactive map showing the last known location and status of each node.

The backend will be hosted on a server in the cloud. Nodes will continually update the server with their status via POST requests.

# Criterion For Success

We aim to achieve the following performance metrics:

- 1.5 kg maximum mass

- Cover 7500 m^2 (North Quad) with 4 nodes

- Display the last known location, time connected, and battery voltage for all nodes via our system monitor

- 3 hour battery life

- 5 Mb/s WiFi available to laptops and smartphones in the coverage area

[*Link*](https://courses.engr.illinois.edu/ece445/pace/view-topic.asp?id=71252) *to assciated WebBoard discussion*