Project :: ECE 445 - Senior Design Laboratory

#	Title	Team Members	TA	Documents	Sponsor
57	Device to track laundry machines and availability	Christopher Song Michael Fong Robert Audino	Dhruv Mathur	design_document1.pdf design_document2.pdf design_document3.pdf design_document5.pdf design_document6.pdf final_paper1.pdf proposal1.pdf proposal2.pdf
	Problem: Not all apartments come with in unit washing machines, so there is usually a communal washing machine that is either within the building or in another building nearby, which would require you to carry your dirty laundry with you to put it in. The problem in this is that tenants would not know if there was an available machine, and there isn’t an easy way to track the availability of a machine other than staying in the room and waiting for the person to come and finish their laundry. This also applies to students in dorms such as our own university. Solution: Our solution to this problem would be an app that is connected to sensors on each machine to show if one is available for use. We would also implement a queue system in which you can put yourself in line for use of the washing machine which would make it so you do not have to wait in the room for the machine. The way the queue works is as follows. People sign up to use a washer or a dryer, but not any specific machine, since we don’t want 5 people in line for washer 1 when washer 2 is completely open. In order to prevent line cutting, only the next person in line is notified when a machine opens. In order to prevent the line getting backed up by someone who isn’t using their laundry privileges, we are implementing two solutions. First, we will add a grace period of 15 minutes so that if you don’t change out your laundry within 15 minutes, the next person in line gains your privileges. Second, if something comes up and you can’t do your laundry right now, we will add an option to leave the queue immediately and allow the next person in line to use the machine. Solution Components: Subsystem #1: Washing machine/Dryer vibration sensor. This subsystem will use a vibration sensor to track the current status of the washing machine or dryer (in use or not in use). We thought about using a heat sensor, but since not all wash and dry cycles are hot, this wouldn’t always work. Subsystem #2: Pressure Sensor: Even if a washing machine or dryer is finished, there still may be clothes inside. To make sure that the machine is truly ready for the next user, we are going to use a pressure sensor to check if the clothes are still present or not. Subsystem #3: Locking mechanism: Once the washing machine is available for the next person to use, there would be a lock on the door which would take in a password or combination that is randomly generated and sent only to the next user to open and use the machine. Subsystem #4: This subsystem will be in charge of relaying information provided by the washing machine status sensors to an app using bluetooth. An arduino with a Bluetooth communication module can be used for this purpose. Subsystem #5: The app that will track washing machine status and allow users to sign up for a queue to use the washing machines. A washing machine/dryer is listed as available only if the following two criteria are met. Firstly, the machine must be totally stopped, which would indicate that the washing or drying is done. The app would receive this information from the vibration sensor. Secondly, the machine has to be empty, meaning that the washed/dried clothes have been removed. Our pressure sensor will communicate this information. Criterion for Success: The system is able to accurately track statuses of washing machines. System is able to provide status information of washing machines to an app. Users of the app are able to sign up for a queue to use the washing machines. The device locks the machine and unlocks once the generated code is entered.

Featured Project

# PROJECT TITLE: Bracelet Aid for deaf people/hard of hearing

# TEAM MEMBERS:

- Aarushi Biswas (abiswas7)

- Anit Kapoor (anityak3)

- Yash Gupta (yashg3)

# PROBLEM

We are constantly hearing sounds around us that notify us of events occurring, such as doorbells, fire alarms, phone calls, alarms, or vehicle horns. These sounds are not enough to catch the attention of a d/Deaf person and sometimes can be serious (emergency/fire alarms) and would require the instant attention of the person. In addition, there are several other small sounds produced by devices in our everyday lives such as washing machines, stoves, microwaves, ovens, etc. that cannot be identified by d/Deaf people unless they are observing these machines constantly.

Many people in the d/Deaf community combat some of these problems such as the doorbell by installing devices that will cause the light in a room to flicker. However, these devices are generally not installed in all rooms and will also obviously not be able to notify people if they are asleep. Another common solution is purchasing devices like smartwatches that can interact with their mobile phones to notify them of their surroundings, however, these smartwatches are usually expensive, do not fulfill all their needs, and require nightly charging cycles that diminish their usefulness in the face of the aforementioned issues.

# SOLUTION

A low-cost bracelet aid with the ability to convert sounds into haptic feedback in the form of vibrations will be able to give d/Deaf people the independence of recognizing notification sounds around them. The bracelet will recognize some of these sounds and create different vibration patterns to catch the attention of the wearer as well as inform them of the cause of the notification. Additionally, there will be a visual component to the bracelet in the form of an OLED display which will provide visual cues in the form of emojis. The bracelet will also have buttons for the purpose of stopping the vibration and showing the battery on the OLED.

For instance, when the doorbell rings, the bracelet will pick up the doorbell sound after filtering out any other unnecessary background noise. On recognizing the doorbell sound, the bracelet will vibrate with the pattern associated with the sound in question which might be something like alternating between strong vibrations and pauses. The OLED display will also additionally show a house emoji to denote that the house doorbell is ringing.

# SOLUTION COMPONENTS

Based on this solution we have identified that we need the following components:

- INMP441 (Microphone Component)

- Brushed ERM (Vibration Motor)

- Powerboost 1000 (Power subsystem)

- 1000 mAh LiPo battery x 2 (hot swappable)

- SSD1306 (OLED display)

## SUBSYSTEM 1 → SOUND DETECTION SUBSYSTEM

This subsystem will consist of a microphone and will be responsible for picking up sounds from the environment and conducting a real-time FFT on them. After this, we will filter out lower frequencies and use a frequency-matching algorithm to infer if a pre-programmed sound was picked up by the microphone. This inference will be outputted to the main control unit in real-time.

## SUBSYSTEM 2 → VIBRATION SUBSYSTEM

This subsystem will be responsible for vibrating the bracelet on the wearer’s wrist. Using the vibration motor mentioned above, we should have a frequency range of 30Hz~500Hz, which should allow for the generation of a variety of distinguishable patterns. This subsystem will be responsible for the generation of the patterns and control of the motor, as well as prompting the Display subsystem to visualize the type of notification detected.

## SUBSYSTEM 3 → DISPLAY SUBSYSTEM

The Display subsystem will act as a set of visual cues in addition to the vibrations, as well as a visual feedback system for user interactions. This system should not draw a lot of power as it will be active only when prompted by user interaction or by a recognized sound. Both of these scenarios are relatively uncommon over the course of a day, which means that the average power draw for our device should still remain low.

## SUBSYSTEM 4 → USER INTERACTION SUBSYSTEM

This subsystem is responsible for the interaction of the user with the bracelet. This subsystem will include a set of buttons for tasks such as checking the charge left on the battery or turning off a notification. Checking the charge will also display the charge on the OLED display thus interacting and controlling the display subsystem as well.

## SUBSYSTEM 5 → POWER SUBSYSTEM

This subsystem is responsible for powering the device. One of our success criteria is that we want long battery life and low downtime. In order to achieve this we will be using a power boost circuit in conjunction with two rechargeable 1000 mAh batteries. While one is charging the other can be used so the user doesn’t have to go without the device for more than a few seconds at a time. We are expecting our device to use anywhere from 20-50mA which would mean we get an effective use time of more than a day. The power boost circuit and LiPo battery’s JST connector allow the user to secure and quick battery swaps as well.

# CRITERION FOR SUCCESS

- The bracelet should accurately identify only the crucial sounds in the wearer’s environment with each type of sound having a fixed unique vibration + LED pattern associated with it

- The vibration patterns should be distinctly recognizable by the wearer

- Should be relatively low cost

- Should have prolonged battery life (so the power should focus on only the use case of converting sound to vibration)

- Should have a small profile and a sleek form factor

Project Videos

Group59_DemoVideo