IOTLondon 22nd May '12

Quest for alow-power home hub

@paul_tanner

Scenario

● Many devices● Many services● Many protocols● Standards? DHYB● Crazy mess of

visualisations● Exploding routers!● It can only get worse

Hub

● Handle diverse sensors/ actuators

● Interact with various cloud services

● Single connection to home router

● Modularity/ Openness

HUB

sensors/ actuators

devices

sensors/ actuators

cloud services

Requirements

● Modular protocols● Downloadable config.● Buffer storage● Rule support● Open source● Durably packaged● Affordable● Low power

Local Devices

● 433 Mhz (prop)● 868 Mhz (prop)● Zigbee (profiles)● One-wire● 6LowPAN● RS232 Serial● UDP on LAN

Cloud Services● Cosm/ pachube

● Incl. SSL

● Thingiverse● Nimbits● AMEE● Wunderground● Proprietary APIs

● AlertMe● etc ...

Available Tech

● Nanode (Atmel)

● OpenKontrol

● SK Pang (MBED)

● BeagleBone (ARM)

● Raspberry Pi

● FriendlyARM

● Digi ConnectPort

● NSLU2 (Slug)

● Hacked routers etc.

c

SWOT – SKP Gateway

● MBED● Performance● Memory● Libraries

● Slot for 2nd RFM12● Robust packaging● Only one slot for

Xbee/ XRF

SWOT - OpenKontrol

● Two radio slots in addition to RFM12

● Lower cost processor● Restricted memory● Daughterboard

(Ethernet port)● Promise of lower

power● Indicators

Others

● Nanode

● used by OEM● BeagleBone (ARM)

✔ linux stack + node.js✔ “capes”

● FriendlyARM

● Pi (unobtainable any time soon)

✔ linux stack✗ hardware ecosystem

Example App

● Monitors emit UDP multicast

● Temperature from XRF-based sensors

● Additional data from AMEE and wundergr.

● Energy and temperature to pachube

● Feedback in graphs, twitter alerts etc.

Tests So Far

● Building kits with minimal doc?

● Some things feasible with each platform

● e.g. TCP sockets● Current library issues

● No UDP multicast for Arduino

● linux with node.js version discrepancies www.nodejs.org

Issues

● Concurrency● O/S or not?

● Support in libraries● e.g. multicast

● Memory requirements● Packaging● IDE, languages

● nodejs/ python vs. c++ www.asmithillustration.com

Conclusions

● Today: jury is still out● Initially O/S and

libraries will decide● Packaging is soluble● Memory could

therefore be a killer● Finally, power use

Questions?

www.slideshare.net/paul_tanner

@paul_tannerwww.e-ssociation.com/blog

Comparative Factors

Platform O/S On (W) S/Save (W)

Sleep multicast enclosure

OK Gateway

* 0.7 Y

MBED * 1.7 Y

Beaglebone linux 2.5 Y

NSLU2 linux

iMac OS/X 75 50 2 Y

PC Win7 100 52 1 Y

* could use qp, FreeRTOS, Contiki etc.