Project

# Title Team Members TA Documents Sponsor
48 Pitched Project (Prof Manuel Hernandez) Insole for Gait Monitoring and Furthering Research of Fall Risk in Older Adults
Jess Sun
Lily Hyatt
Nasym Kushner
Kaiwen Cao design_document1.pdf
final_paper1.pdf
grading_sheet1.pdf
proposal1.pdf
# Insole for Gait Monitoring and Furthering Research of Fall Risk in Older Adults

Team Members:
- Jessica Sun (jzsun2)
- Nasym Kushner (nasymjk2)
- Lily Hyatt (lhhyatt2)


# Problem

A major cause of injury, especially for the elderly population, is from falls. 8 million adults over the age of 65 are injured each year, and an estimated 3 million require emergency care for injuries. In the US alone, on average 32,000 deaths a year are due to falls, and worldwide, falls are the second most common cause of unintentional death. Currently, early smart home fall detection technology for high risk adults is lacking and fails to incorporate relevant data from monitoring changes in fall risk and frailty.

As a response to the gap in the market, Dr. Manuel Hernandez’s lab created a TENG sensor designed for the insole. Our goal is to integrate the sensor into our device to monitor gait for data collection, and improvement and characterization of sensor. The device should be portable, allowing the user to walk as they would normally. It should be able to accurately convert the signals from the sensor into a digital format and transmit via Bluetooth.

The challenges we face moving forward are: Measuring/dealing with high voltage (up to 40V) and low current (on the order of micro amps). Addressing the portability/wearability of the current sensor as well as its implementation into our design. And implementing and testing its self powering nature.

# Solution

As gait is one of the most important indicators of health, we also plan to improve development for a pressure sensing insole. This insole will have a custom triboelectric pressure sensor to analyze timing of the patient’s steps. An added feature of the triboelectric nanogenerator is its self powering ability. The main feature we plan on improving is usability. This will be accomplished through bluetooth integration with an easy to use mobile application which will store and display the collected data. This will make it easier to monitor patient status and enable further research on the effects of fall risk and fragility through data collection, advancing understanding of behavioral mechanisms related to balance and gait dysfunctions in older adults.

The triboelectric sensor we will be working with is described as high voltage, low current. It detects load by passing current when changes in load are made. We aim to test the current custom triboelectric sensor to benchmark “high”, “medium”, and “low” loads based on factors such as weight, age, and gender and set thresholds to mark this as interpretable data for measuring step timing. We also need to create hardware that is comfortably wearable and compatible with the sensor, and synchronize the sensors from the left and right feet.

As stated, the most important factor we plan to address is ease of usability. We understand that even though technology can unlock great opportunities for patient care, products that are difficult to use or incompatible diminishes these effects. As such, we strive to make our interface as user-friendly and intuitive as possible. Through the creation of a robust app, seamless data collection, and durable hardware, we hope to create a system patients and providers will enjoy using.

# Solution Components

## Measurement Subsystem
This subsystem measures step timing and load and makes the signal suitable for microcontroller.
Pressure sensing insole (this component will be provided by Dr. Manuel Hernandez)
Resistors (step high measurement voltage)
diode (protect microcontroller against voltage spikes)
capacitor (filter noise)
ADS8689 (ADC)

## Data Processing Subsystem
This subsystem process the measurements and exports them via Bluetooth)
ESP-32
Bluetooth Module

## Power Subsystem
This subsystem powers the data processing subsystem
3.3V Battery
Power switch
LED (indicate On/Off and status)

## Housing Subsystem
Hold power and data processing subsystem
Compact 3D printed case with spot for switch, LED, and openable battery compartment
Velcro strap (for nearby attachment)

## Shoe Subsystem
The sensor will be placed inside the sole of a sandal located on the heel.
Orthopedic podiatric friendly sole with cutting to fit sensor
Thin padding over the sensor for comfortability and protection of the sensor while not detracting from the load sensing capabilities

## Mobile Application Subsystem
The app will receive Bluetooth data from the insole and display relevant information.
Functions:
Receive data from ESP-32 over bluetooth
Display status of device
Visualize and export data


# Criterion For Success

- Calibration of each sensor. Custom made sensors will have slight variations, so in order to capture the most standardized data sets between the two sensors worn on both feet, calibrations must be made.

- Sensor accuracy. Data collected should have consistent readings under repeated same loading conditions. This should remain true under high step frequency (up to ~5Hz)

- Voltage safety implementation. The voltage imputed into the microcontroller should always be within the rated voltage (3.3V or 5V depending on pin).

- Ease of Use: The whole system (sole and user interface) should be easy and intuitive to use. The user should not have to worry about the internet settings on their device. The device should be easy to set up/install.

- Durability: The product should be able to work properly and maintain accurate readings through rigorous usage over many cycles with variable loading weight and frequency.

Illini Voyager

Cameron Jones, Christopher Xu

Featured Project

# Illini Voyager

Team Members:

- Christopher Xu (cyx3)

- Cameron Jones (ccj4)

# Problem

Weather balloons are commonly used to collect meteorological data, such as temperature, pressure, humidity, and wind velocity at different layers of the atmosphere. These data are key components of today’s best predictive weather models, and we rely on the constant launch of radiosondes to meet this need. Most weather balloons cannot control their altitude and direction of travel, but if they could, we would be able to collect data from specific regions of the atmosphere, avoid commercial airspaces, increase range and duration of flights by optimizing position relative to weather forecasts, and avoid pollution from constant launches. A long endurance balloon platform also uniquely enables the performance of interesting payloads, such as the detection of high energy particles over the Antarctic, in situ measurements of high-altitude weather phenomena in remote locations, and radiation testing of electronic components. Since nearly all weather balloons flown today lack the control capability to make this possible, we are presented with an interesting engineering challenge with a significant payoff.

# Solution

We aim to solve this problem through the use of an automated venting and ballast system, which can modulate the balloon’s buoyancy to achieve a target altitude. Given accurate GPS positioning and modeling of the jetstream, we can fly at certain altitudes to navigate the winds of the upper atmosphere. The venting will be performed by an actuator fixed to the neck of the balloon, and the ballast drops will consist of small, biodegradable BBs, which pose no threat to anything below the balloon. Similar existing solutions, particularly the Stanford Valbal project, have had significant success with their long endurance launches. We are seeking to improve upon their endurance by increasing longevity from a power consumption and recharging standpoint, implementing a more capable altitude control algorithm which minimizes helium and ballast expenditures, and optimizing mechanisms to increase ballast capacity. With altitude control, the balloon has access to winds going in different directions at different layers in the atmosphere, making it possible to roughly adjust its horizontal trajectory and collect data from multiple regions in one flight.

# Solution Components

## Vent Valve and Cut-down (Mechanical)

A servo actuates a valve that allows helium to exit the balloon, decreasing the lift. The valve must allow enough flow when open to slow the initial ascent of the balloon at the cruising altitude, yet create a tight seal when closed. The same servo will also be able to detach or cut down the balloon in case we need to end the flight early. A parachute will deploy under free fall.

## Ballast Dropper (Mechanical)

A small DC motor spins a wheel to drop [biodegradable BBs](https://www.amazon.com/Force-Premium-Biodegradable-Airsoft-Ammo-20/dp/B08SHJ7LWC/). As the total weight of the system decreases, the balloon will gain altitude. This mechanism must drop BBs at a consistent weight and operate for long durations without jamming or have a method of detecting the jams and running an unjamming sequence.

## Power Subsystem (Electrical)

The entire system will be powered by a few lightweight rechargeable batteries (such as 18650). A battery protection system (such as BQ294x) will have an undervoltage and overvoltage cutoff to ensure safe voltages on the cells during charge and discharge.

## Control Subsystem (Electrical)

An STM32 microcontroller will serve as our flight computer and has the responsibility for commanding actuators, collecting data, and managing communications back to our ground console. We’ll likely use an internal watchdog timer to recover from system faults. On the same board, we’ll have GPS, pressure, temperature, and humidity sensors to determine how to actuate the vent valve or ballast.

## Communication Subsystem (Electrical)

The microcontroller will communicate via serial to the satellite modem (Iridium 9603N), sending small packets back to us on the ground with a minimum frequency of once per hour. There will also be a LED beacon visible up to 5 miles at night to meet regulations. We have read through the FAA part 101 regulations and believe our system meets all requirements to enable a safe, legal, and ethical balloon flight.

## Ground Subsystem (Software)

We will maintain a web server which will receive location reports and other data packets from our balloon while it is in flight. This piece of software will also allow us to schedule commands, respond to error conditions, and adjust the control algorithm while in flight.

# Criterion For Success

We aim to launch the balloon a week before the demo date. At the demo, we will present any data collected from the launch, as well as an identical version of the avionics board showing its functionality. A quantitative goal for the balloon is to survive 24 hours in the air, collect data for that whole period, and report it back via the satellite modem.

![Block diagram](https://i.imgur.com/0yazJTu.png)