The Internet of the

LandSteve Dawes

July 2014

The pre-cursors

• In 2006 installed a 1-Wire weather station and a network of sensors

(temperature, humidity and lightning) in my house, conservatory and

greenhouse. Monitored with OWW (One Wire Weather) and own s/w

using a small LINUX system.

• Used X10 (signals over mains) for significant home automation

(scripts running under LINUX)

• In 2013 I did some experiments monitoring data-centre temperature

using 1-Wire networks with both LINUX and Arduino based hosts.

• Produced some very useful results

• Showed that we could do significant extra monitoring cheaply

The 1st Watering System

• In 2010 decided to manage water and

automatically water my small greenhouse at home.

• Built an Arduino based system to pump water

between 3 tubs … to optimise rainwater

management and to feed drippers in the

greenhouse.

• The watering system worked, but not well. I learnt

some lessons!

The lessons

• It required too much wiring!

• The s/w was cumbersome.

• The resistance based depth sensing (measured

full, half full and empty), was prone to error.

• The system was stand alone, hard to track status

and troubleshoot.

Unexpected Problems

• Problems are not always the ones you expect!

• My anti-syphoning device whistled at a frequency

above my hearing threshold, unfortunately my

neighbours are slightly younger!

• In 2012 a drunk driver crashed into our house… (in

spite of it being in a quiet cul-de-sac)…… I haven’t

yet reinstated the weather and watering

systems…..

The Land

• In 2011 we bought 1 acre of derelict land on May Hill in

Gloucestershire

• Besides being a lovely location intent was to grow

vegetables, both outdoors and under glass

• The location is10 miles from home. We did not want to

visit every day, indeed we wanted to be able to take

significant holidays.

• Solution:- monitoring and automation.... The Internet of

Things in action.

2012 & 2013

• Cleared the land and improved the fencing

• Put in raised beds and planted fruit trees

• In 2013 constructed a 20.5 * 10.5ft and a 6 * 8ft

greenhouse

• Also a cabin with views!

2014

• Built the 1st version of an IOT based watering

and monitoring system

• Powered by 12V battery and solar panels

• Has so far coped with two 3 week absences

• My intent is to develop it significantly further……

The Tub Hardware

Processor

(Digispark)

CISECO ERF

(wireless)

Ultrasonic

Distance Sensor

Relay to drive

the Pump

Sensor Network

CISECO XINORF

(= Arduino UNO + ERF)1-Wire

Temperature

DS1820B

Humidity

Sensor

DS9490RData Logging Shield

RTC + SD Card * Planning to add Soil Moisture Sensor(s)

* Initially based on the Data Centre work

* Under test in home greenhouse

* May separate logger in due course

Monitor

UNO

GPRS Shield

4 * 20

LCD Display

Currently under development

CISECO ERF

Issues to date

• Inconsistency of the depth sensor (echoes etc.)

• 1st Relay board and wireless interference

• Program memory in Digispark (6k)

• Plumbing and cases

• Slugs, rabbits, squirrels and mice

• It always takes longer than anticipated!!!!!!!

IOT Thoughts

• Although what I have accomplished so far is

simple, some useful ideas and principles are

evolving.

• The next slides share some generic thoughts.

Principles

• IOT devices should have a default behaviour and

not be dependent on a master controller

• Peer to Peer communication should be allowed

• Devices should be as simple as possible

A Generic IOT Device

Wireless

Processor Sensor

Control

Optional

Generic IOT Software

Protocol Engine

Rules Engine

Common Actions

Device Specific Actions

Monitors the wireless and

and actions any relevant

messages

Acts on rules stored in

non-volatile memory

Generic actions for the

rules to use

Device specific actions

for the rules to use

The Rules

• Mean that a device can be repurposed without

having to change the code

• Rules loaded from a master controller

• After rules loaded master need not be present

• Needs to support complex conditional statements

Example Rule

• IF [Device,Sensor] < 25 THEN {PUMP ON; DELAY

60;PUMP OFF};

• IF = Common Action

• [Device,Sensor] = Common Action, does and RQI to

get the info from the relevant device… in this case

soil moisture.

• PUMP ON/OFF = Device Specific Actions

• DELAY = Common Action

My Next Steps

• Finish the current version of the monitor and deploy (by 1/9/14)

• Improve wireless range

• Select a soil moisture sensor and add to the Sensor Network (may not be 1-Wire) (by 1/10/14)

• Build a sensor network for each greenhouse (for 2015)

• May use SODAQ and combine sensor network functionality with the monitor

• Build an IOT fan controller (= water without the depth sensor), (for 2015)

• Change processor … (CISECO RFu 328?)… need more memory

• Use a water system with valve to let gravity top-up the greenhouse tubs (from 1000L tanks at

top of hill), (for 2015 if landslip problem sorted!)

• Finish 1st version of the rules engine

• Define/Adopt a protocol and implement it

QUESTIONS?