Project

# Title Team Members TA Documents Sponsor
21 Modular 3D Holographic Display
 Charles Ekwueme
Pavan Hegde
Taofik Sulaiman
 Stephanie Jaster design_document2.pdf
design_document3.pdf
design_document4.pdf
design_document1.pdf
final_paper1.pdf
proposal2.pdf
proposal1.pdf
RFA
Taofik Sulaiman (tosulai2), Pavan (pavanh2), Charles Ekwueme (cekwue2)

Project Description:
Problem -
Displaying objects in 3D formats has tremendous benefits but is severely limited. Current modes of 3D display are expensive and can be disadvantageous, and at times even harmful to certain users, especially if viewed for extended periods of time (e.g. 3D picture via red/blue anaglyph glasses). Anaglyph glasses are very eye tiring and lead to headaches since they distort images or the user’s eye focus. Further, solutions like VR headsets also require wearables which are heavy, also cause eye fatigue and are limited to one user.
Our main goal is to allow users to better visualize objects in a 3D space without the limitations of a 2D screen and without eye fatigue.

Solution Overview -
General description of idea
Our device would take in 3D model files (e.g. STL/CAD file) via USB or other I/O then display them as a hologram projection by converting the 3D model into 4 different 2D images that are then projected into the hologram display. This solves the problem by allowing users to input their own 3D models (as STL/CAD files) and create an interactive display without the use of a wearable or any of the health implications that come with those.

What makes our project unique?
Our project is novel in that we would be taking the simple home made hologram experiment that is available on phones and building a version that can sit on a table to display bigger scenes and allow user input to modify the scene or interact with the object.
Unlike other solutions, our design will decouple the graphics processing and display logic from the control device (i.e. laptop/computer).

Alternatives/Competitors
Other modes for 3D viewing feature AR/VR devices and 3D images which use glasses.

Technical Overview
* Our project will use a 3D model file as an input file in which it will convert this file into a 2D video/image intended to be used for the Holographic display.
* This project would incorporate and require the design a board that interfaces with the holographic display, and possibly a sensor that tracks user motion. To make the project interesting we could combine input from different sensors to account for error.
* We will allow limited manipulation of the projected scene by allowing the user to move the object around the scene. There will be no need to re-process the 2D image back to 3D as the object itself will not be modified however its position or orientation may be.

Solution Components
* Display
- This unit will render the hologram via a standard 2D screen and shaped glass. Example
- This subsystem will include any required video driver and 2D, LCD screen
* IO Peripherals
- This subsystem will encompass input to the processing unit for 3D model input or control signals.
- Likely this will be implemented via a USB controller that takes in the serial input from a laptop/computer.
* 3D->2D mapping algorithm
- No specific algorithm is currently in mind however with the use of graphics libraries, specifically OpenGL ES, calculating appropriate projections onboard will be simplified significantly.
* Processing Units
- As a result of graphics processing requirements, likely this will include a low power CPU (e.g. ARM based) and a graphics accelerator of some form.
* Power Subsystem
- Used to power components from other systems reliably. This may include AC/DC converters, wall adapters and or voltage regulators.

Criterion for Success
* Final Milestone 1: Successful static rendering of 3D model to holographic display. (3D to 2D mapping)
* Final Milestone 2: Successful dynamic rendering (changing smoothly and requiring real-time scene calculation) of 3D model to holographic display.
* Final Milestone 3: Accurate user control of the holographic object from serial input or from capacitive sensor input with maximum of 2 second delay.
* Final Milestone 4: Displayed image has decent resolution: i.e. image look clear.
* Final Milestone 5: Can operate for extended periods of time without fail (at least 20 seconds).

References:
* Holographic Display:
- https://www.youtube.com/watch?v=7YWTtCsvgvg
* 3D-2D Mapping Algorithm Resources:
- https://www.khronos.org/opengles/

Healthy Chair

Ryan Chen, Alan Tokarsky, Tod Wang

Healthy Chair

Featured Project

Team Members:

- Wang Qiuyu (qiuyuw2)

- Ryan Chen (ryanc6)

- Alan Torkarsky(alanmt2)

## Problem

The majority of the population sits for most of the day, whether it’s students doing homework or

employees working at a desk. In particular, during the Covid era where many people are either

working at home or quarantining for long periods of time, they tend to work out less and sit

longer, making it more likely for people to result in obesity, hemorrhoids, and even heart

diseases. In addition, sitting too long is detrimental to one’s bottom and urinary tract, and can

result in urinary urgency, and poor sitting posture can lead to reduced blood circulation, joint

and muscle pain, and other health-related issues.

## Solution

Our team is proposing a project to develop a healthy chair that aims at addressing the problems

mentioned above by reminding people if they have been sitting for too long, using a fan to cool

off the chair, and making people aware of their unhealthy leaning posture.

1. It uses thin film pressure sensors under the chair’s seat to detect the presence of a user,

and pressure sensors on the chair’s back to detect the leaning posture of the user.

2. It uses a temperature sensor under the chair’s seat, and if the seat’s temperature goes

beyond a set temperature threshold, a fan below will be turned on by the microcontroller.

3. It utilizes an LCD display with programmable user interface. The user is able to input the

duration of time the chair will alert the user.

4. It uses a voice module to remind the user if he or she has been sitting for too long. The

sitting time is inputted by the user and tracked by the microcontroller.

5. Utilize only a voice chip instead of the existing speech module to construct our own

voice module.

6. The "smart" chair is able to analyze the situation that the chair surface temperature

exceeds a certain temperature within 24 hours and warns the user about it.

## Solution Components

## Signal Acquisition Subsystem

The signal acquisition subsystem is composed of multiple pressure sensors and a temperature

sensor. This subsystem provides all the input signals (pressure exerted on the bottom and the

back of the chair, as well as the chair’s temperature) that go into the microcontroller. We will be

using RP-C18.3-ST thin film pressure sensors and MLX90614-DCC non-contact IR temperature

sensor.

## Microcontroller Subsystem

In order to achieve seamless data transfer and have enough IO for all the sensors we will use

two ATMEGA88A-PU microcontrollers. One microcontroller is used to take the inputs and

serves as the master, and the second one controls the outputs and acts as the slave. We will

use I2C communication to let the two microcontrollers talk to each other. The microcontrollers

will also be programmed with the ch340g usb to ttl converter. They will be programmed outside

the board and placed into it to avoid over cluttering the PCB with extra circuits.

The microcontroller will be in charge of processing the data that it receives from all input

sensors: pressure and temperature. Once it determines that there is a person sitting on it we

can use the internal clock to begin tracking how long they have been sitting. The clock will also

be used to determine if the person has stood up for a break. The microcontroller will also use

the readings from the temperature sensor to determine if the chair has been overheating to turn

on the fans if necessary. A speaker will tell the user to get up and stretch for a while when they

have been sitting for too long. We will use the speech module to create speech through the

speaker to inform the user of their lengthy sitting duration.

The microcontroller will also be able to relay data about the posture to the led screen for the

user. When it’s detected that the user is leaning against the chair improperly for too long from

the thin film pressure sensors on the chair back, we will flash the corresponding LEDs to notify

the user of their unhealthy sitting posture.

## Implementation Subsystem

The implementation subsystem can be further broken down into three modules: the fan module,

the speech module, and the LCD module. This subsystem includes all the outputs controlled by

the microcontroller. We will be using a MF40100V2-1000U-A99 fan for the fan module,

ISD4002-240PY voice record chip for the speech module, and Adafruit 1.54" 240x240 Wide

Angle TFT LCD Display with MicroSD - ST7789 LCD display for the OLED.

## Power Subsystem

The power subsystem converts 120V AC voltage to a lower DC voltage. Since most of the input

and output sensors, as well as the ATMEGA88A-PU microcontroller operate under a DC voltage

of around or less than 5V, we will be implementing the power subsystem that can switch

between a battery and normal power from the wall.

## Criteria for Success

-The thin film pressure sensors on the bottom of the chair are able to detect the pressure of a

human sitting on the chair

-The temperature sensor is able to detect an increase in temperature and turns the fan as

temperature goes beyond our set threshold temperature. After the temperature decreases

below the threshold, the fan is able to be turned off by the microcontroller

-The thin film pressure sensors on the back of the chair are able to detect unhealthy sitting

posture

-The outputs of the implementation subsystem including the speech, fan, and LCD modules are

able to function as described above and inform the user correctly

## Envision of Final Demo

Our final demo of the healthy chair project is an office chair with grids. The office chair’s back

holds several other pressure sensors to detect the person’s leaning posture. The pressure and

temperature sensors are located under the office chair. After receiving input time from the user,

the healthy chair is able to warn the user if he has been sitting for too long by alerting him from

the speech module. The fan below the chair’s seat is able to turn on after the chair seat’s

temperature goes beyond a set threshold temperature. The LCD displays which sensors are

activated and it also receives the user’s time input.

Project Videos