Project

# Title Team Members TA Documents Sponsor
16 Smart Assistive Walking Stick for the Visually Impaired
Haoyang Zhou
Sanhe Fu
Yihan Huang
Yucheng Zhang
design_document1.pdf
final_paper1.pdf
final_paper2.pdf
proposal1.pdf
Yushi Cheng
# Problem
More than 250 million people worldwide suffer from varying degrees of visual impairment, which has a profound impact on their physical health, mental well-being, and overall quality of life. Individuals with impaired vision face three key challenges when navigating their surroundings: obstacle avoidance, indoor path planning, and key object localization. Especially in the intersections on the road, the road conditions in this area are complicated, and the blind cannot directly identify the traffic lights and traffic signals. In China, most intersections have no voice prompt system designed for the blind, and there are fast-moving vehicles in this section, which is very dangerous for the blind.
The most commonly used assistive tool for visually impaired individuals is the white cane, which provides users with tactile feedback. However, the standard white cane has a limited detection range, only sensing obstacles within its physical length, and cannot identify distant or elevated obstacles. But these situations are very common in the intersections. Moreover, the white cane provides only basic physical feedback and lacks the capability to convey detailed environmental information, such as road intersections and navigation directions. As a result, in unfamiliar or complex environments, relying solely on a white cane makes precise navigation difficult, forcing users to depend on external assistance or their memory of previously traveled routes.

# Solution overview
Our solution to this problem is the development of an intelligent smart cane. The smart cane can improve walking speed and safety both outdoors and indoors, and we have designed it with a focus on blind people crossing intersections. This advanced cane is equipped with sensors to measure the distance to obstacles, a GPS system for precise outdoor positioning, and computer vision technology to capture detailed environmental information, such as traffic signs and other critical landmarks. Additionally, the smart cane features motor-controlled omnidirectional wheels for directional guidance and provides real-time voice feedback to assist users in navigating their surroundings with greater ease, speed and confidence. In outdoor environments, aid from GPS can not only help the user to walk in strange environments that are not similar but also help them to be more confident in their familiar environments. It will also show a great ability when navigating the users to walk in indoor environments, where the obstacles are usually many and unexpectable. When the user passes through the intersection area, GPS will help give the alert, the camera takes information about the surrounding environment, such as traffic lights and their duration, traffic signs, and whether there are vehicles around. This information is identified by computer vision algorithms and then prompted by voice to the user. And the strong detecting ability provided by the laser sensor of our smart cane can help to avoid crashing into obstacles, especially to avoid crashing into the people and objects that are moving fast speed.

# Solution components
## Main Control Module
-Raspberry Pi serves as the core processor, responsible for receiving and processing data from various modules and controlling other components to provide the corresponding feedback. It will process the information, like the distance measured by the laser sensor, location information from GPS, and the environment signals fron vision system, to determine the direction to go and give feedback to the user by sending signals to the motor and earphones.
-Use Computer Vision algorithms, i.e. YOLO to utilize the images captured by camera and recognize the signals in the environment, and thus gain the information for better guidance.

## Data Collection Module
-Laser sensor is used to measure the distance between the user and obstacles.
-Inertial measurement unit provides orientation estimates.
-GPS is used for precise outdoor positioning.
-Camera captures environmental images.
## Feedback Module
-Motor is used for direction control and guidance.
-Earphone voice prompts provide environmental information to the user.

# Criterion For Success
Our design incorporates advanced sensor-based distance detection to prevent collisions, camera-enabled object recognition for identifying road signs and other key elements in the environment, and GPS-oriented navigation to ensure accurate positioning. Compared to traditional white canes, its success can be measured by several key improvements, including faster walking speeds in both indoor, outdoor settings and intersections, more precise and efficient navigation, more accurate road inforamtion and an overall enhancement in user independence and mobility.

Miniaturized Breath Sensors

Rui Cai, Yiyang Chen, Qiaozhi Huang, Yingzhuo Wang

Featured Project

## Group Member:

- Yiyang Chen[yiyangc5];

- Rui Cai[ruic2] ;

- Yinzhuo Wang[yw28];

- Qiaozhi Huang[qiaozhi2]

## Problem

Flow monitoring is crucial in many applications. We want to build a miniaturized breath sensor system that can monitor asthma.

## Solution Overview

In this wearable respiratory monitoring device, a new fluid measurement device, similar in principle to a traditional hotline, will be used to collect real-time data on a person's breathing rate. In contrast to the traditional hotline, materials such as graphene and carbon nanotubes are used as probes which is much more robust and have lower TCR(temperature coefficient of resistance). This material--graphene fiber (GF) will be welded into Wheatstone bridge and the voltage output of GF will demonstrate the velocity of air flow by controlling the temperature of the GF. Then, we will use filter to eliminate noise of the signal and do Fourier Transform to demonstrate the frequency of respiration. After that, this signal can be sent to smartphone. With previous training data online, we can analyze the signal of respiration and conclude the probability of asthma. We plan to use a mobile app to show users breathing data, summarize the data and make recommendations. We will use Bluetooth for data transmission.

## Solution Components

### Flow Sensor System

The resistance of a specific material changes at different temperatures, and the flow sensor system's control circuit measures the change in resistance to achieve constant temperature control of the sensor probe. In the thermostatically controlled fluid sensor subsystem, the heat carried by the fluid at different speeds through the sensor probe is the same as the heat provided by the compensation circuit, so that the fluid flow rate can be accurately measured. Graphene and carbon nanotubes are widely used in these sensor probes, and sensor probes using pencil and paper have recently been proposed as a new type of sensor probe. The processing of sensor probes is challenging and there are advantages and disadvantages to various methods, including soldering and metal clamping, and we are trying to design a small, low-cost and robust sensor probe.

### Circuit

The circuit of our design consists of three sections: Wheatstone Bridge, Amplifier, and Feedback control. We need to adjust the resistance of the Wheatstone Bridge to construct and balance a working space for GF sensor. As it states in previous, the flow would change the GF material’s resistance, thus create a voltage difference on both sides of the Wheatstone Bride. This difference will be amplified by the operational amplifier, and the voltage regulator will change the excitation voltage on the Wheatstone Bridge in order to keep the temperature of GF stable. The difficulty of our design come from the feedback control design. One possible way is to use transistors. In addition, if we want to eliminate the environmental temperature effect, specific temperature compensation measure should be implemented, such as add a temperature sensor in another Wheatstone Bridge. The circuit should keep the GF temperature stable and output the voltage change, this output signal will transfer to next section and be processed and analysed.

### Signal Processing and Analysis

First, we must use filter to eliminate noise of signal. As we all know, the high frequency noise can have a negative influence on the signal, which does harm to our analysis of asthma. Therefore, we must do FFT on signal we get from circuit and use high frequency filter to eliminate certain noise. Second, to calculate the probability of asthma, we must collect training data of respiration online. These data can be used to do machine learning. With those training data, the signal can be analysed easily.

### Result

Visualization Bluetooth Low Energy (BLE) features Low power consumption and faster transmission speeds. Therefore, we choose BLE to transmit data to mobile phone on this wearable respiratory monitoring device that requires long battery life and only a small amount of data transfer. We're also going to keep the interface simple and add analysis function to the app.

## Criterion of success

- Wearable and Miniaturized In the current study, wearability and miniaturization directly determine the industrialization potential of this new type of sensor. The portability of the product will help to achieve 24/7 patient health monitoring. Therefore, the development of wearable and miniaturized health monitors is considered as one of the criteria to measure the success of the product.

- Comfortable and Flexible Flexible sensors that conform to human science will significantly improve the comfort of wearing the product and determine the user's willingness to wear it. Flexibility and comfort are one of the goals of the product.

- Environment Friendly Environmental protection is becoming an increasingly important issue to be addressed today. The development of environment-friendly sensors is the goal of this research. Conventional biosensors will inevitably use environmentally hazardous materials such as plastic. this study will use degradable materials, such as paper, instead of plastic for product development.

- Low Cost Low-cost respiratory health monitors facilitate product penetration and daily use.

- Reliable and Stable As a medical product, the reliability of the product determines the safety of the life of the target object. A highly reliable and high-performance respiratory monitoring device can effectively guarantee the occurrence of accidents.

## Distribution of Work

Yiyang Chen (ME), Rui Cai (EE) and Qiaozhi Huang (ME) will be responsible for the construction of the fluid sensors, the design of the wearable device, the design and debugging of the circuitry, which are closely linked and we agree that there is no need for an overly clear distribution of work, Rui Cai will lead the development and fabrication of the circuitry. Yingzhuo Wang (ME) will be responsible for the development of the wireless Bluetooth data transmission technology, the visualization of the monitoring results and the implementation of the interactive functions.