high six the sign language glove

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High SixThe Sign Language Glove

Group 6

Group Members

• Kirk Chan – CpE• Brian Troili – EE• Ali Mizan – CpE• Laura Rubio-Perez – EE & CpE

Project Introduction

Motivation

• Fresh idea to the UCF community• This project has the potential to help the speech impaired• Based on the research, technologies necessary were

interesting– Android development– Bluetooth communication– Personal taste

Goals

We want the following key factors:

HARDWARE SOFTWARE● Low-power ● Android

● Lightweight ● Accurate & fast translations

● Wireless ● Support text & audio translations

Specifications

Component Design Specification

Hand gesture translation Less than 1s

Glove weight Less than 1.5lbs

Battery life (from one charge) Approximately 20hr

Application startup Within 5s

Bluetooth connection range Up to 50m

Default gesture library American 26 letters, 10 numbers

Design Approach

Design Overview

Hardware Components

• Flex Sensors▪ Able to detect changes in bend/flex▪ Changes its resistance at several points

along the device▪ When a current is applied, it creates a

voltage divider

Hardware Components

Hardware Components

• Pressure Sensors▪ Acts as a force sensing resistor▪ When the sensor is unloaded, its

resistance is very high▪ When pressure is applied, its

resistance decreases

Hardware Components

Analog/Digital Converter (ADC)

• Serial communication preferred.• Large number of input channels.• Avoid serial address conflict.

- ADS7828• I2C compatible• 8 Channel ADC• variable I2C address

Hardware Components

Accelerometer and Gyroscope

– Inertial Measurement Unit (IMU)– Speed demand allow for serial buses.

- ITG3200/ADXL345 combo board➔ 3.3V input➔ I2C compatible➔ 3 axis each➔ calibrate to 2, 4, 8, and 16g

Hardware Components

• ADXL345

• 3-axis accelerometer• Low power• Low current use: 40μA in measuring

mode and 0.1μA in stand by • Suited for mobile device applications

Hardware Components

• ITG3200

• 3-axis digital gyroscope• Low-cost motion sensor• Features 16-bit analog-to-digital

converters• Supply voltage range: 2.1V - 3.6V• Current consumption of 6.5mA

Hardware Components

Wireless Communication

Wifi Bluetooth NFCSecure connection Portable connection Low power

Approx. 100m range Approx. 100m range Approx. 7-8in

Hardware Components

HC-06 Bluetooth Module• Bluetooth v3.0• Operating voltage: 3.6V – 6V • Working current of 40mA• Approximately $6• Range: 30ft

Hardware Components• Microcontroller

MSP430g2553 ATmega328p ATmega32u4Operating Voltage 3.3V 5V 5.5V

Digital I/O Pins 12 14 12

Analog Input Pins 12 6 12

Clock Speed 16MHz 16MHz 16MHz

Architecture RISC RISC RISC

Flash Memory 16KB 32KB 32KB

Hardware Components• Development Environment

Arduino IDE Code ComposerFree Free

Open source (Unlimited support ) Limited support

Extensive libraries Direct access to control registers

avr-gcc compiler C/C++ compilers and assembly

Hardware components• Battery

Nickel Cadmium Nickel Metal Hydride Polymer Lithium Ion Rechargeable Rechargeable Rechargeable

Low energy density High energy density Highest energy density

Good performance in low temperature

Can operate in low temperature

Resistant to overcharge

Not environmental friendly Limited service life Require circuit protection

High-self discharge Degradation in performance Age quickly

Hardware components

• LP-063048 Polymer Lithium Ion Battery

• Extremely light weight• Outputs a 3.7V at 1000 mAh.• Features 2C continuous discharge• Robust power source under extreme

conditions• Long-term self-discharge rates• Approximately $9• Bought from: Sparkfun

Hardware components• Power Cell-LiPo Charger/Booster

• Single cell boost converter to 3.3V and 5V and Micro-USB charger all in one

• Boost converter is based on the TPS61200 from Texas Instrument

• Low input voltage synchronous boost converter

• Operating input voltage range from 0.3V to 5.5V

• Fixed and adjustable output voltage from 1.8V to 5.5V

Hardware components• Power Cell-LiPo Charger/Booster

• micro-USB charger uses the MCP73831• It charges 3.7V LiPo cells at 100mA. • Limits the charge current based on the die

temperature during high power• It utilizes a constant- current/ constant-voltage

configuration• The constant-voltage regulation has four options:

4.20V, 4.35V, 4.40V, and 4.50V

Hardware components• LP2985 Regulator

• Low-dropout: • 280 mV at 150-mA load current• 7 mV at 1-mA load

• Low-noise operation with a typical output noise of 30 μVRMS

• Consumption of only 0.01 μA when the ON/OFF pin is pulled low.

• Overcurrent and thermal protection

Software Components

Android vs iPhone

• iPhone– Can only be developed in Mac– Apps written in objective C– Apple development software

only works with other apple development software

• Android– Cross platform capable

integrated development environment

– Familiarity with the Java language

– The most popular mobile platform

Android IDEs

IntelliJ (free version)• Advantages:

– Less buggy– More intuitive– Faster– Better GUI

• Disadvantages:– Java, Groovy, or Scala are only 3

languages supported in free version

Eclipse• Advantages:

– More plug-ins available– More commonly used

• Disadvantages:– Has bugs and crashes a lot

Software Components

• Two main components: – Android Application

• Is the interface between the user and the classification algorithm– Takes in raw data from glove– Displays letter on screen

– Translator• Translates letters just by checking flex sensors and accelerometer to see

if they fit certain boundaries• The application has some default boundaries set, but can be

customized by user

Traditional Bluetooth Setup

Our Bluetooth Setup

Our Android Setup

Threshold – Based Algorithm

• How to recognize gestures? • Compare sensor input from glove to high

and low thresholds.

• Boundaries can be adjusted• Default boundaries we created come with

application• New boundaries stored in local memory

and can be reset back to defaults

Successful Recognition of a letter

Sensor High Threshold

Sensor data

Low Threshold

Within boundaries?

S1 18 15 13 yes

S2 11 11 9 yes

S3 25 21 17 yes

• How to segment data?• Recognition algorithm only called when hand is

still for about .5 seconds

• Which sensors need to be read?• The flex and pressure sensors alone can

differentiate between 32 of the 36 character• For the 4 hand gestures that have same shape,

orientation is used to differentiate them

Threshold – Based Algorithm

Final FinancingDESCRIPTION QTY PRICE

Flex sensors 2.2” 11 $79.50

IMU Digital Combo Board (3-Axis Gyro/Accelerometer) 1 $51.96

Flexiforce Pressure Sensors 4 $79.80

Bluetooth module (Free) 1 $0.00

Microcontroller (Atmega 328P) 1 $37.97

PCB 2 $584.78

Miscellaneous Surface Mounting - $85.00

TOTAL - $919.00

Boeing sponsorship - - $518.00

Total Available from Sponsorship - $0.00

Over budget - $401.00

Total per person - $100.25

Progress

Issues

• No such thing as universal boundaries• Boundaries differ from user to user

• Hard to define boundaries • Even with just one user, it may be difficult to define boundaries that

work well most of the time• BLE and Hidden Markov Model• TPS61200 reference errors

Approaching the issues

• No Universal Boundaries• allow the user to train boundaries for their hand

• Boundaries hard to define• To make letters easier to classify, add a tolerance on top of the boundaries• Ie: if tolerance = 5%, high and low boundaries both multiplied by 1.05

• BLE and Hidden Markov Model• Switched to classic Bluetooth (3.0)• Switched to deterministic algorithm

Questions?

high six the sign language glove

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