1. technology and computing

SENSORS FOR IOT
ROBERT VAN SCOY
EMBEDDED TECH CON, JUNE 10, 2015
EVOLUTION OF SENSORS
» Early 20th Century – the age of the clipboard and pencil
 Some sensors are very old -- Seebeck observed the thermocouple effect in 1821
 Early sensor readouts use analog meters and gauges
 “Data acquisition” involves reading the meters and writing the numbers down
 Data analysis is done with pencil, paper and slide rule
8-Jun-15
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Photo credit: Jimi Jones
Possibilities start here // 2
EVOLUTION OF SENSORS
» Mid 20th Century – automation arrives
 Electronic amplifiers let sensors output useful levels of voltage or current
 Analog process controllers allow sophisticated automation of control tasks
 “Data acquisition” typically involves reading paper graphs from chart recorders
 Data analysis is still mostly manual
8-Jun-15
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Photo credit: Trojan Nuclear Power Plant
Possibilities start here // 3
EVOLUTION OF SENSORS
» Late 20th Century – computerization and MEMS
 Analog sensor outputs are digitized for processing by computer systems
 IC technology enables direct digital outputs from many sensor types
 Digital data is immediately available for local or remote computer analysis
 MEMS technology revolutionizes the cost and size of many “physical” sensors
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Photo credit: Invensys Process Systems
Possibilities start here // 4
THE IC/MEMS COST REVOLUTION
» IC technology has made some sensors nearly free
 An entire data acquisition chain -- Sensor + amplifier + filter + A/D + signal processing –
can be integrated into a single IC with a digital output
 One example -- digital temperature sensors now cost <$0.10 in quantity, or even come
free as part of other chips
 Sensors for light, sound, magnetic fields, etc. have also become very low cost.
 Precision location sensing is now a “$5 problem” for IC-based GPS receivers.
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Credit : Texas Instruments
Possibilities start here // 5
THE IC/MEMS COST REVOLUTION
» Some “hard” sensing problems have become easy
 MEMS (MicroElectricalMechanicalSystems) are miniature machines with movable
parts that are built with integrated circuit fabrication technology
 MEMS technology has created accelerometers and gyroscopes that cost a few $,
and also lowered the cost of traditional functions such as pressure sensors
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Credits: Institute of Navigation, ST
Possibilities start here // 6
THE IC/MEMS COST REVOLUTION
» Since sensors are so cheap, sensors are spreading everywhere
 There are 12+ sensors in a high-end smartphone, dozens in a car
 There is a constant stream of new sensors and new sensor-enabled devices
 Much of the promise of IOT is the promise of data from “cheap sensors everywhere”
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Credit: IHS
Possibilities start here // 7
WHAT CAN SENSORS SENSE?
» Environmental
 Temperature, humidity, altitude, location, light,
images, magnetic fields, gases
» Physical
 Acceleration, force, vibration, pressure, strain,
sound
» Electrical
 Voltage, current, power, phase, RF
» Physiological
 Heartrate, BP, EKG, Blood O2, etc
8-Jun-15
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Credits: Analog Devices, Intel
Possibilities start here // 8
WHAT DO SENSORS SENSE?
» Baseline data is important
 Often its hard to know what “normal” is unless we do long-term data monitoring
 Example: vibrations as traffic passes over a bridge
 Trend towards 24/7 monitoring, so low power sensors are often important
» Sensors sense more than the obvious
 Obviously webcams need security, but - Room temperature changes can give away comings and goings
 Electrical load changes can reveal what equipment is being used and when
 Even the most “boring” sensor data may raise security and privacy concerns
 IOT acceptance (and company reputations) depend on public confidence that data
is secure and not being misused
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Possibilities start here // 9
SENSORS IN COMPUTING DEVICES
» Mobile devices have lots of sensors
 Cameras!
 RF: GPS, 3G, WiFi, Bluetooth, NFC
 Accelerometer, gyro, magnetometer
 And sensors to make the UI work . . .
» Sensor interfaces are usually simple
 I2C, SPI interfaces are common for low-bandwidth sensors
 Often sensors have low-power modes where they can still generate interrupts
 Some designs have dedicated “sensor hub” processors for low-power monitoring
 Image sensors typically use mobile-centric interfaces such as MIPI CSI-2
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Credit: Smartphoneworld.me
Possibilities start here // 10
SENSORS IN COMPUTING DEVICES
» Embedded computers typically have
“Hardware Monitor” functions that:
 Measure CPU die temperature
 Measure temperatures at other points
 Control system fan or alarms
(with varying amounts of software intervention)
 Monitor important system power supply voltages
 Measure the voltage of the CMOS battery under load (for life prediction)
 Monitor external battery charge state and/or control battery charging
» Kontron and other vendors provide APIs to access internal sensor data
 Data is very useful for system thermal validation
 Many customers don’t take full advantage of operational data for PM, fault monitoring
 Module/carrier board designs allow adding sensors that make sense for application
 It’s likely more sensors will be added as usefulness is understood – e.g. logging of
shock handling history when the computer controls delicate equipment
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Credit: Kontron
Possibilities start here // 11
EXTERNAL SENSOR INTERFACES
» Historically sensor interfaces were analog
 Many different analog “standards”: raw transducer outputs, 0-10V, 4-20mA, etc
 Sensors had point to point wiring to the host system
 Long cables needed in industrial settings, subject to noise pickup & other issues
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Credit: Emerson Global Users Exchange
Possibilities start here // 12
EXTERNAL SENSOR INTERFACES
» Digital interfaces have proliferated in recent decades
 Serial “busses” like RS-422, RS-485, CAN, MODBUS, Fieldbus are commonly used
for connecting sensors to host computers
 Typically these busses are multidrop and addressable – allow connection of many
sensors to one bus and so eliminate a lot of wiring
 Ethernet variants such as PROFINET and EtherCAT are gaining popularity
 Digital sensors are often “smart” (e.g. run own self-calibration routines)
 Many vendors provide “transmitters” that interface analog sensors to busses
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Credit: Kontron, wut.de
Possibilities start here // 13
EXTERNAL SENSOR INTERFACES
» RF links gaining traction now
 Sensors can connect to hosts or each other via WiFi, Bluetooth, ZigBee, etc
 Mesh topologies have reliability advantages in large sensor networks
 Sensor and radio power consumption is sometimes critical – some applications
need to run for years from a small battery
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Credit: Kontron, EMWhiz Technologies
Possibilities start here // 14
SOME EXAMPLES
» Many industrial PC customers already implement some form of “IOT”
 System controller often also provides a gateway for sensor data
 Remote monitoring, PM, problem diagnosis, customer support all have high value
 Hardware and software support from system vendors makes “industrial IOT” easier
8-Jun-15
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Credit: Kontron
Possibilities start here // 15
SOME EXAMPLES
» New applications are based on ubiquitous / dispersed / mobile sensors
 Often there’s value in 24/7 baseline monitoring – but this generates lots of data
 Wired network uplinks often not available, need to use 3G or other radios.
 Power consumption is critical when line power is not available
 Gateways often needed to aggregate data onto a single uplink. Local data preprocessing can save communications costs, bandwidth, power
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Credit: Decentlab
Possibilities start here // 16
SOME EXAMPLES
» Rugged mobile computers interface with truck sensors via CAN
 Wealth of data is available on system performance for PM
 “IOT is integrated with other functionality for e.g. scheduling, maps, driver logs
 Typically 3G or satellite uplink transmits data for real-time remote monitoring
 Some benefits are indirect (theft prevention, driver compliance with rules and laws)
 Economic value well proven – major Kontron customer has 250K+ units on road
8-Jun-15
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Credit: Decentlab
Possibilities start here // 17
PRECISION AGRICULTURE
Joint partnership with Mimos, and UPM, funded by Malaysian
Government
Purpose: Increase crop yield
Results: 3 yields in 1 year (normally only 1)
Details
 3 greenhouses, semi and fully controlled in west and east Malaysia
 Used sensors to monitor growing variables
 Data collected through Kontron gateway and tracked with Mimos software
8-Jun-15
Possibilities start here // 18
WIRELESS SENSING NETWORK (WSN) FOR PRECISION
AGRICULTURE
Sensor Node
Temperature
Sensor Node
pH
CLOUD
COMPUTING
AGRICULTURAL
CORPORATION
ANALYST
Sensor Node
Humidity
Router
Sensor Node
Moisture
Sensor Node
Soil Conductivity
8-Jun-15
Gateway
In Greenhouse
/ IP Rated Housing
FRONTEND
INTERFACE
Possibilities start here // 19
WSN OVERALL SYSTEM ARCHITECTURE
Sensor Node
pH & EC
Water & fertilizer
Water tank
Mixing & dosing
tanks
Valves
Embedded Controller
CAN Network
Sensor Node
Moisture
Sensor Node
Humidity
Sensor Node
pH & EC
Sensor Node
Temperature
Zigbee Network
SYSTEM OFF
ON
WSN Gateway
Harvest!!!
THANK YOU
FOR YOUR ATTENTION
www.kontron.com
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