The aLife Home System

The aLife Home System

The aLife Home System

Home automation with a different approach

Market flooded They all take the same approach: GUI’s that

wait for user input aLife is event driven based on

Temperatures Security Energy

aLife Example Event

Project Goals And Objectives

#1 goal: Embedded Android Create a smart and customizable system Little to no learning curve Focus on active user interface Easy integration with any home Integrate with 3rd party devices Low cost

Project Block Diagram

ZigBee Base

Base Station

Remote Module

Remote Modules - Communications

Module Communication Network– Wireless ZigBee More reliable, robust than wired Flexibility in module installation location Acceptable data rate (up to 250kbps) Acceptable transmission range (up to 75m) Open source, abundance of cheap

hardware and software available

Remote Modules – Block Diagram

Remote Modules – Schematic pg1



Remote Modules – Power Supply

Power Supply Requirement Specifications 3.3VDC output, <= 20mV peak to peak ripple Source >= 250mA Efficiency >= 80% Work off of both 120VAC and battery

Implementation – National Semi LM2841XMK-ADJL switching buck DC-DC converter 3.3VDC output, 2mV peak to peak ripple

(simulated) 300mA max 83% efficiency (simulated)

Remote Modules – Power Supply

Remote Modules – MCU

MCU Requirement Specifications: Built in ZigBee transceiver Available ZigBee Consumer protocol stack Operate at >= 15MHz >= 32kB built in FLASH, >= 2kB built in

RAM Features: digital I/O, PWM, ADCs, UART,

12C


MCU Design Implementation Freescale MC13213R2

Built in ZigBee transceiver 20 MHz 60kB FLASH, 4kB RAM 8x ADC, 2x UART, 1x I2C, 5x PWM, 22x GPIO

BeeStack Zigbee 2007 compliant protocol stack

Program firmware in C using CodeWarrior IDE


Remote Modules – Base Comms

Communication with Android Base Requirement Specs Must use a standard that is compatible with

both Android base and remote module hardware

Implementation RS232 using TI SN65C3221EPWR

transceiver Up to 1M baud rate 15kV ESD protection No hardware handshaking

Remote Modules – Base Comms

Remote Modules – Type 1 Functions

120VAC Power Sensor Requirement Specifications Measure up to 1800W (max power rating

for a standard wall outlet) Resolution down to 5W at 3% accuracy < 10m Ohms AC impedance >2kV electrical isolation between AC and

digital side Ability to disconnect AC output to save

appliance power


Power Sensor Design: Allegro Micro ACS709LLFTR-20BB-T Hall effect

based AC current sensor – exceeds specs AC peak detector circuit for current sensor

output On Semi MC33072ADR2G instrumentation amplifier Gain controlled via ADI AD5241BRZ1M 1M Ohm, 256

step digital Pot for power ranging from 3W up to 1700W

Theoretical resolution down to 3W at 2% accuracy (still needs to be tested)

In series software controlled relay



Temperature Sensor Requirement Specs: Accurate to within +/- 2 degrees Celsius Range of -30 to +100 degrees Celsius I2C interface Remote temperature sensor loop (type 2

function) Implementation

NXP SA56004ED,118 temperature sensor Meets the above requirements



Type 2 Requirement specifications: 2 DAC and digital outputs – Lighting, motor

control 2 ADC inputs – Remote current sensor input 1 Temperature sensor loop – measure

outdoor temp 1 Software controlled relay – garage door

control Surge and short circuit protection for all I/O


Type 2 Function Implementation Digital and DACs outputs- PWM fed into low

pass op amp circuits using Micron MCP665-E/UN dual op amp chip Can change from gnd to 3.3V in 3ms Output can drive +/- 90mA

2 ADC inputs Surge protection - 400W TVS, clamp at 7.3V Short protection - 70mA hold, 130mA trip PTCs 10A relay



Remote Modules – ZigBee Transceiver

ZigBee Transceiver Requirement Specifications Transmission range of >= 30m ZigBee 2007 compliant protocol

ZigBee Transceiver Design Single port antenna design to minimize

components Transmission range still unknown pending

antenna development Will use Freescale’s BeeStack Zigbee 2007

protocol, specifically designed for this MCU

Remote Modules – ZigBee Transceiver

Remote Modules – PCB

PCB implementation: We will generate a layout from our

schematic in Altium and manufacture our own custom PCBs with the following target specs: 2-4 layer boards 3”x3” or smaller outside dimensions Double sided component placement to

minimize board area

Base Station Hardware

Design decision - Functionality

Need a board to be able to run the android operating system.

Has to be able to handle multiple clients accessing it at the same time (up to 5).

Supports serial communication to interact with the ZigBee devices on the network

Design decision - Practicality

It’s a wall mounted unit, so the overall weight should be less than 5 pounds

Should be able to be wall mounted Needs to be powered off a wall outlet LCD should be bigger than 2 inches to be

considered easy to interact with

Processor

i.MX51processor board

i.MX51 Specifications

Processor – ARM Cortex A8 Runs anywhere from 600 MHz – over 1GHz Meets the minimum android system

requirements of 200 MHz Supports Ethernet Connectivity Contains multiple interfaces that we

needed to interact with our system

Picture of Complete System

Included in this picture:Processor boardLCD ScreenExpansion board

Communication Scheme

Serial Communication is the main way this board talks to the network

Problem – Android OS doesn’t support communication over serial ports!

After some difficulty implementing serial comm., we decided on using some lower level C code as an intermediary

Format for the C code

Base Station Software

Specifications and Requirements

Functional:

Base station must be able to accept up to 5 simultaneous service request on a first come first serve basis

Multiple request to service the same notification must only be serviced once

Must be able to add/remove/update a row in database with 98% reliability

Security:

All user must have unique login; Allowed 5 unsuccessful attempts before lockout

Only registered remote client devices may have service request fulfilled by the base station

Notifications:

All notifications must have a unique notification ID Users shall only receive notifications that they are registered to receive

Design Approach and Implementation

V-Model Proven and well structured Allows for redesign

Android Operation System Supports notifications Supports secure socket communication Database support

Eclipse IDE w/ Android Development Tools (ADT) Plug-in Free Best support for Android Development

V – Model

Design Decision Database Management System

(DBMS)

SQLite Needed the use of a database for our software Had several choices, but implemented SQLite:

Extensive native support provided by Android platform.

Will run on Base Station, no need for additional hardware

No need for purchase server space. Relatively fast compared to other DBMS

Software Block Diagram

Software Block Diagram – Background Services

Fields: PowerNotif (Boolean): Field tells whether a powered device notification is set up SecurityNotif (Boolean): Field tells whether a security device notification is set up ControlNotif (Boolean): Field tells whether a control device notification is set up ActiveDevices(Device [ ]): Array of active devices in the network RequestedService (String): String representation of a request

Methods: BaseStation ():Constructor to create the GUI interface for our system. getActiveDevices(): Takes in no parameters. Returns all active devices in database. addDevice(Device X): Adds specified device to network and database. No return. removeDevice(Device X): Removed specified device from network and database. No

return. setNotifications(): Takes no parameters. Sets all initial notifications booleans. These will

dictate which notifications will be checked for continuously throughout the program. pollDevices(ActiveDevices): Takes in all active devices and updates their information in

the database tables. Returns nothing. socketParser (ByteStream): Takes in a socket byte stream and returns the requested

service in string format. requestService (Device X, RequestService): This method will take in a device and service

request and will fulfill the said service. Returns nothing.

Software Block Diagram – Devices Class

Fields: ID (Int) : Device's ID Name (String): Name provided by user for device Status (Boolean): Provides status of device, on or off

Methods: getID(): Takes in no parameters. Returns an Int, the value of the devices ID. setID(Int ID): Takes in an Int and updates ID field. Does not return anything. getName(): Takes in no parameters. Returns a String, the value of the devices

Name. setName(String name): Take in a String and update Name field. Does not return

anything. getStatus(): Takes in no parameters. Returns Status of device setStatus(Boolean Status): Takes in a boolean and updates Status of device. Does

not return anything.

Software Block Diagram – PowerDevice

Fields: TotalWatts (Int): Provides total watts used by device SetWatts (Int): Provides user defined limit for watt usage CurrentTemp (Int): Provides current temperature information SetTemp (Int): Provides user defined limit for temperature PollTime (Int): Time the information was polled SetTime (Int): Set time for notification purposes Timeframe (Int): Timeframe for power information i.e. 7 days or 30 days

Methods: PowerDevice(): Constructor to create object. Will have generic and specific constructors. turnOn(): Takes in no parameters. Sends message to ZigBee device to turn on turnOff(): Takes in no parameters. Sends message to ZigBee device to turn on getTemp(): Takes no parameters. Polls ZigBee device for temperature. setTemp(Int Temp): Sets ZigBee device with provided temperature. Does not return

anything. getWatt(): Takes no parameters. Polls ZigBee device for wattage. getTimeframe(): Takes in no parameters. Returns the timeframe field. setTimeframe(Int Timeframe): Sets the timeframe field. Does not return anything.

Software Block Diagram – SecurityDevice

Fields: SetTime(Int): Provides set time for any notifications

Methods: SecurityDevice(): Constructor to create object. Will have generic and specific constructors. isOpen(): Takes in no parameters. Returns true if ZigBee device is open. IsLocked(): Takes in no parameters. Returns true if ZigBee device is locked.

Software Block Diagram – ControlDevice

Fields: SetTime(Int): Set time for notification purposes

Methods: ControlDevice(): Constructor to create object. Will have generic and specific

constructors. turnOn(): Takes in no parameters. Sends message to ZigBee device to turn on turnOff(): Takes in no parameters. Sends message to ZigBee device to turn on

Database Structure

The SQLite database will be utilized to store information about current users, devices, power history, notification history, and notification set ups. Each of these elements will be have their own table in our database with their own specified fields.

Remote Client Device (RCD)


Reliability No crashes 90% Notification Rate with connection

Usability Easy to answer notifications

Unobtrusive Notifications only when needed


Android Phone Secure Connection Seamless transition between WiFi and

Cell Network Fast notifications

<10 sec with a connection

Research and Design Decisions

Minimal focus on control Prevent detraction from the standard

practices

Notifications based on events Untapped market Cost savings

Notifications Packet Structure

Type 1 (Power)

Type 2(Power)

Type (Power)

Type 4 (Temperature)

Type 5 (Temperature)

Notification type

Notification type

Notification Type

Notification Type

Notification Type

Notification Level

Notification Level

Notification Level

Notification Level

Notification Level

Notification ID# Notification ID# Notification ID# Notification ID# Notification ID#

Button 1 Text Button 1 Text



Current Temp

Current Set Point

Current HVAC Mode

Page Flip Page Flip Page Flip Page Flip Page Flip

Display State with Control Options

Display History with Notification Options


Display State with Control Options


Class Structures

Android Notification Service

Class Structures

aLife Menu System

Design Approach and Implementation

GUI

Testing – Base Station

Hardware Verified communication serially Could interact with the screen and it be user

friendly Software

Tested the adding of users and devices to the DB. Checked for concurrency issues among multiple

clients Tested that the software would generate a

notification whenever it received a signal to do so

Testing – Remote Client and Wireless Network

Remote Client Showed that we can populate information

from the Base Station’s database Can interact with the Base Station through

notifications Maintain TCP/IP connection with the system

Wireless Network No real testing, unable to get the protocol

stack configured correctly

Budgeting

Base Station Freescale i.MX51: $0.00 (on loan from

Advantor Systems) Remote Client

HTC Dream Android smartphone: $0.00 (owned by a group member)

Samsung Captivate Android smartphone: $0.00 (owned by a group member)

Remote Modules – per module costs on following table

Budgeting – Per Remote Module

Remote Modules Freescale MC13213 – $0.00 (sampled from

Freescale)

Item Type Manufacturer

Part Number Cost/1 Multiple

MCU Freescale MC13213R2 $0.00

Dual op amps Micron MCP665-E/UN $1.46

Temp Sensor NXP SA56004ED,118 $0.85

Relay Tyco PB114006 $1.18 2

Terminal Block Tyco 1-284093-0 $2.21

DC-DC Converter

National LM2841XMK-ADJL

$3.90

Transformer Pulse BV030-7136.0 $3.36

Current Sensor Allegro ACS709LLFTR-20BB-T

$4.46

Instrum Amps On Semi MC33072AD $1.10

Digital Pot ADI AD5241BRZ1M $2.33

Balun Murata LDB212G4005C-001

$0.42

Crystal AVX CX3225SB16000E0FPZ25

$3.30

Misc $5.00

Budgeting – Remote Module Component Costs

Total per module: $100.00 Additional costs for ZigBee base module

RS232 transceiver – TI SN65C3221EPWR, $2.63

DB9 connector - Norcomp 171-009-113R911, $3.00

No terminal block – -$2.21 Bare PCBs (6 sq inch) – $60.00 each Total cost of 4 remote modules: $640.00

Budgeting - Summary

Total budge allowance - $600 Base Station - $0.00 Remote Client - $0.00 Remote Modules - $640

Total = $640 Slightly over budget, but we had a

good estimation from the start

Milestone

Successes/Difficulties

Successes Working high level product from the base

station to user notification Successfully manipulated our embedded

platform to handle the requests that we wanted

Difficulties Zigbee Serial Port Communication

Questions

Any questions or comments?

Documents

The aLife Home System