Design World/EE Network - IoT Handbook

of THINGSINTERNET

HANDBOOK

September 2015

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What will the IIoT mean to manufacturers? Page 50Big future for cyber-physical manufacturing systems. Page 36

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2 DESIGN WORLD EE Network 9 2015 designworldonline.com

Cover image courtesy of: Mentor Graphics

1608 Would the IoT make for a boring movie?

10 Low-power wireless links let the IoT proliferate Through beacon technology, smartphones will passively pick up information about activities nearby, extending the IoT to a whole new range of applications.

16 The circuit protection connection for wearables and the IoT Circuit protection technologies and board layout strategies help promote safety, reliability and connectivity.

22 The IoT and connected highways Dedicated short-range communication techniques could usher in connected cars and safer driving.

27 Industrial power for the Internet of Things

Many devices on the Industrial IoT will need rugged primary and rechargeable lithium batteries to provide reliable, long-term power.

30 Real-time operating systems for wearable devices in the IoT Operating systems and the way they handle

tasks can make or break applications such as activity trackers and

fashion electronics.

34 SoMs speed the move to the Industrial Internet of Things Systems-on-modules and platform approaches can help keep IIoT efforts from getting lost in the weeds of interfacing and hardware development.

36 Big future for cyber-physical manufacturing systems The real value of the IoT for manufacturers will be in

the analytics arising from cyber-physical models of

machines and systems.

42 A case of IoT fatigue? Market studies show consumers are less enthusiastic about connected products these days. But electronic suppliers are still designing components and software aimed at quickly implementing the Internet of Things.

46 Building IoT gateways to the cloud Test instruments ensure connections to the cloud

coexist peacefully with IoT communication schemes.

48 Data, data everywhere, but no insights in sight

50 What will the Industrial Internet of Things mean to manufacturers? How will the IIoT affect manufacturing operations and processes? Experts weigh in.

54 IIoTthe technological changes coming to automation equipment and systems Experts discuss the changes in technology that will enable greater connectivity and data gathering, and how it will affect your designs.

60 Whos investing in IIoT and why Medical, automation, automotive, food and beverage, material handlingso many industries plan to take advantage of IIoT. Experts explain why.

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50

CONTENTS

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Would the IoT make for a boring movie?

LELAND TESCHLERExecutive Editor@DW_LeeTeschler

T heres a new movie coming out about the life of Apples Steve Jobs. Despite what you might conclude from movies like this one, the birth of new technologies seldom involves much drama. At least thats the conclusion Ive come to after reflecting on a talk I attended in 1988 during the International Solid State Circuits Conference (ISSCC).

The ISSCC is considered one of the premier technical conferences for IC design. Papers accepted for presentation there are generally considered either

important or interesting. Twenty-seven years ago, I was among those listening to a paper that Im pretty sure organizers lumped into the interesting category. The main author was a kid from the Massachusetts Institute of Technology who, judging by his demeanor at the podium, was pretty happy to be there. He should have been: The work he described was his masters thesis. Though it wasnt even doctorial work, it got selected for ISSCC. That must have been quite a plum.

The kids project demonstrated a way of letting ICs communicate with each other wirelesslysingle chips couldnt do that back then. He was thinking about RFID-like applications such as chips embedded

in animals (cattle, for example) that could be scanned and identified as they passed through a gate.

The kid went on to describe an IC containing transmission and receive coils.

Rather than drive current through the coils, which would consume a lot of power, the chip switched

its coil impedance high and low to change, thereby inducing an amplitude modulation in an external magnetic field. The amplitude modulation resulted in a data rate of around 50 kBd.

The research was part of an array of early investigations into wireless topics. Though it was not the basis for future work in the area, a decade or so later the same ideas would gel into both RFID concepts and into a discipline known as near field communication (NFC). NFC is the technology that lets two cell phones exchange information simply by touching each other. The first NFC patents came in the late 1990s when a couple of Brits worked out the details for use in Star Wars toys. Now, of course, NFC is found in mobile payment schemes, such as Apples Apple Pay, as well as in more prosaic uses, such as swapping selfies on smartphones. Both RFID and NFC are expected to have big roles in IoT scenarios.

It would have been hard to see that in those pre-world-wide-web days. Back then, there were a lot of refinements necessary before wireless technologies were ready for prime time. For example, NFC schemes now use a frequency shift modulation rather than the AM described in the ISSCC paper. Nevertheless, that early work demonstrated the concept. So you might wonder whether people in that ISSCC audience

realized they were seeing the first glimmers of ideas that would eventually become significant communication technologies.

Well, if anybody had those feelings, I certainly couldnt detect them. The room where the

presentation took place was only half full. As I recall, the author got polite applause and fielded a couple of straightforward technical questions after his talk. There were no dramatic moments.

The kid who gave that ISSCC paper, by the way, was Adam Malamy, an engineer who has gone on to work in video compression and decompression. Safe to say, if moviemakers ever decide to put the beginnings of IoT technologies up on the big screen, theyd have a tough time making Adams small part melodramatic.

NFC is found in mobile payment schemes such as Apples Apple Pay as well as in more prosaic uses

such as swapping selfies on smart phones.

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Low-power wireless links let the IoT proliferate

JASON TOLLEFSONMicrochip Technology

Through beacon technology,

smartphones will passively

pick up information about

activities nearby, extending

the IoT to a whole new range

of applications.

A typical blood pressure cuff as handled by a Bluetooth Smart app. Profiles in Bluetooth are specifications for how a device works in a particular applicationfor low energy devices.

A nalysts project there will be tens of billions of things making up the IoT, and each of these things will require power. The IoT will necessitate innovation in energy-conservation techniques, particularly because many of the ideas envisioned involve remote nodes residing far away from power lines. Extremely low-power microcontrollers (MCUs) and Bluetooth Smart radios can help solve power problems.

There is a lot of debate about just what constitutes the Internet of Things. Is it connected car keys? Is it the connected refrigerator? Despite the debate, a few key aspects have emerged. For one thing, IoT objects are uniquely identifiable. They also connect to the existing Internet infrastructure and offer services that go beyond machine-to-machine techniques.

One particular type of IoT connection that has gotten a lot of attention is that of locale-based services. Examples include getting an instant update on ski conditions as you board the lift, or an instant coupon as you walk in the grocery store. The same capabilities could deliver customized status updates of activities that are close to home, such as your childs tooth-brushing habits.


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It looks as though locale-based services will mainly be delivered by smartphones communicating with low-power MCUs and Bluetooth Smart radio. The Bluetooth Smart spec (also called Bluetooth LE) is basically a low-power version of Bluetooth. It offers designers a simple way to add IoT capabilities. Smartphones now ship with integrated Bluetooth Smart protocol. A smartphone app can control the user experience and manage the data transfer to and from the edge device. Here, an edge device is a mechanism that provides entry into an enterprise or service provider network. Routers and network switches are both examples of edge devices.

Bluetooth Smart can work like whats called a beacon, vastly simplifying the pairing process (that is, establishing a connection between two devices). Beacons can advertise their presence to the smartphone when the two are in close proximity. In contrast, the pairing of two WiFi devices can only take place when a user pushes a WiFi Direct button on the router, which often resides in another room.

When low-power MCUs mate to a Bluetooth Smart radio, the MCUs typically collect sensor data. Typical data might include location or hours

of use. The MCU then stores the data it collects in a usable format. When a smartphone connects with the device, the data uploads and either gets transmitted or displayed.

It is useful to cover Bluetooth beacon capabilities in some detail. Bluetooth beacons are typically

small transmitters (usually battery powered) that beam out information that a smartphone or tablet picks up. Beacons are not new. The Apple iBeacon standard has been out for two years. But it is proprietary and only works with Apple equipment.

The Bluetooth Smart standard is relatively new and of most interest for IoT devices. This new standard enables low-power operation, a benefit for IoT applications. The original Bluetooth spec, now called Bluetooth Classic, offers a longer range and throughput of 2.1 Mbps. But low-data-rate applications like IoT temperature sensors dont need rates this high. Bluetooth Smarts advantage is that it connects quickly, has throughput matching IoT needs and consumes less power.

One recent development in beacon technology is the release by Google of Eddystone, an open-source, cross-platform Bluetooth Smart beacon format. Eddystone supports multiple types of frames, basically data bursts performing various functions.

Bluetooth beacons communicate just one way. For beacons working with smartphones, the usual goal is to send a notification that the phone user can tap. Tapping launches another application that takes some actionaccepting a store coupon, say.

The beacon spec defines something called a Universally Unique Identifier (UUID). This is a 128-bit value that uniquely identifies every specific beacon in the world. A typical use for a UUID might be to find smartphones near a store having a specific UUID, then send the phone users a coupon.

Eddystone also defines a URL frame. A specific location can send out a URL frame instead of a UUID. Doing so would open a Web browser. The typical use example is that of buying a drink from a soda machine

The typical use example is that of buying a drink from a soda machine with a smartphone. For this one-time data transaction, sending out a URL lets the phone user get a drink without having to install an app.


13DESIGN WORLD EE Network designworldonline.com 9 2015

LOW-POWER WIRELESS

with a smartphone. For this one-time data transaction, sending out a URL lets the phone user get a drink without having to install an app.

Ephemeral Identifiers (EIDs) are frames defined with security in mind. There seem to be few details published about this type of frame. Finally, a frame for Telemetry Data is meant for sending diagnostic information about the beacon, such as its remaining battery power.

Readers might wonder why Bluetooth beacons are necessary for locale-based services when GPS is already available. The answer is that GPS transceivers consume a lot of power and arent particularly accurate in densely populated areas. They also dont work well indoors. For example, in a scenario where two bus stops are across the street from each other, GPS might get confused about which was closer to the phone user. Beacons wouldnt have this problem.

LOWERING ENERGY DISSIPATIONThe Bluetooth SIG defines several profilesspecifications for how a device works in a particular applicationfor low-energy devices. Among them is a profile for heart rate. A blood pressure cuff employing Bluetooth communication, for example, might make use of the heart rate profile.

The profile might handle services such as device and blood pressure measurements. The profile would also include a UUIDin this example, probably specifying the manufacturer.

Profiles are spelled out in a section of the Bluetooth spec called the Bluetooth Smart GATT or Generic Attribute Profiles. The profiles are typically supported in the Bluetooth device directly, and all current low-energy application profiles are based on the GATT.

Bluetooth Smart employs several measures to keep energy use low. For example, it uses GFSK, or Gaussian Frequency Shift Keying, while transmitting. This method is simpler and requires less power than classic

One example of a Bluetooth Smart controller is the RN4020 Bluetooth Version 4.1 low energy module. On board is a complete Bluetooth stack. It is controlled via ASCII commands over a UART interface. The RN4020 also includes all Bluetooth SIG profiles, as well as MLDP (Microchip Low-energy Data Profile) for custom data. A built-in PCB antenna is tuned for long range, typically over 100 m.

Bluetooth, which uses non-Gaussian FSK. GFSK isnt compatible with FSK and has a preamble that is different than in Bluetooth Classic. Some Bluetooth radios will work in either of these modes, but must be configured for one mode or the other to do so.

Another benefit of Bluetooth Smart is its packet size. Bluetooth Smart packets are smaller than those of classic Bluetooth by as much as 60%. This means the Bluetooth Smart radio consumes energy for one-third as long as the older standard.

The Bluetooth Smart radio reduces energy use as well by minimizing its connection time. The radio can stay paired with a smartphone without requiring a constant connection. A constant connection consumes constant power, so removing this requirement saves energy. The Bluetooth Smart radio features a Connect Interval and

Slave Latency, which make pairing this way possible.

The connection parameters for Bluetooth Smart were set up with energy efficiency in mind. These parameters determine when and how a peripheral exchanges information with a central unit.



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All in all, connection parameters let peripherals transmit data as frequently as every 7.5 msec, or as infrequently as every 33 min, thus optimizing energy use.

Slave latency lets a peripheral stay asleep (and thus save energy) if it doesnt have data to send, but still send data fast if necessary. The classic example is that of wireless keyboards and mice. They can sleep when there is no data to send, but still have a low latency (and a low connection interval for the mouse).

The central unit sets the connection parameters, but the peripheral can send a so-called Connection Parameter Update Request to change them.

There are basically three different connection parameters. One called the connection interval determines how often the central unit asks the peripheral

for data. Here, the peripheral can set whats called the slave latency period. This factor sets how long the peripheral can ignore the central units request for data. By setting slave latency to some non-zero number, the peripheral can choose how long it can wait when the central unit asks for data. (However, the peripheral can send data any time it needs to.)

Slave latency lets a peripheral stay asleep (and thus save energy) if it doesnt have data to send, but still send data fast if necessary. The classic example is that of wireless keyboards and mice. They can sleep when there is no data to send, but still have a low latency (and a low connection interval for the mouse).

To make sure the peripheral hasnt died somehow, there is another parameter called the connection supervision timeout. This period determines the time from the last data exchange until a link is considered lost. A central unit wont try to reconnect until the timeout has passed. The timeout feature is useful for handling devices

that go in and out of range, where the central unit needs to notice when this happens.

All in all, connection parameters let peripherals transmit data as frequently as every 7.5 msec, or as infrequently as every 33 min, thus optimizing energy use.

LOW-POWER MCU FEATURESOf course, the MCU figures in the power equation. MCU power consumption is largely determined by the power-mode state and clock speed.

Many new MCUs include low-power modes and can change operating modes under software control. Typical operating modes include run, doze, idle, low-voltage sleep and deep sleep. Each of these modes reduces power consumption under specific operating conditions. For example, the PIC MCU has doze and low-voltage sleep modes. In doze, the MCU can run code more slowly than its on-chip peripherals. This reduces current


LOW-POWER WIRELESS

15DESIGN WORLD EE Network 9 2015 designworldonline.com

consumption but still allows peripherals, such as UARTs, to communicate at the proper baud rate. Low-voltage sleep mode switches out the high-performance, on-chip regulator for a low-current regulator. This allows full MCU state retention using a current of only a few hundred nanoamps. A transition from run to low-voltage-sleep reduces current consumption by 99.9%.

Low-power MCUs also offer on-the-fly clock switching. This is the ability to change clock frequency depending on the task. For example, the MCU might run at full clock speed when computing math-intensive filter algorithms on sensor data. If the MCU is in a simple loop and awaiting an interrupt, it might dial back clock speed to reduce power. These methods can reduce current consumption from 5 mA to 26 Aa savings of 99%.

Similarly, many low-power MCUs have smart peripherals that can operate independent of the program execution. They are independent of the MCU core in that, once they are configured, they complete the work without intervention.

For example, the PIC MCU has an integrated analog-to-digital converter (ADC) able to run in sleep mode. It accomplishes this feat by using its own clock and dedicated logic called threshold detect. Threshold detect is the ability to sample a signal, as from a temperature sensor, and wake the CPU only when a specific target is reached. Features like this one can cut ADC current in half.

All in all, use of low-power modes for core-independent peripherals, MCUs and Bluetooth Smart radios make it possible to connect a wide variety of applications to the IoT. Smartphones provide an instant gateway to get online wirelessly. This connectivity will likely let people simplify their lives. REFERENCES

Bluetooth Smart specs developer.bluetooth.org/ TechnologyOverview/Pages/BLE.aspx

Bluetooth module ww1.microchip.com/downloads/en/

DeviceDoc/70005191A%20(1).pdf

Comparing Bluetooth Classic and Bluetooth Smart



The circuit protection connection for wearables and the IoT

JAMES COLBYLittelfuse

Circuit protection technologies and board layout strategies

help promote safety, reliability and connectivity.

T heres one down-side to wearable technology that is unlikely to show up in headlines about the IoT: Human bodies generate static electricity as they move. That static electricity can potentially harm the sensitive electronics that power IoT applications.

To understand the problem, consider the human-body model (HBM), a model used for characterizing the susceptibility of integrated circuits to damage from electrostatic discharge (ESD). The most widely used HBM definition is the test model defined in the military standard MIL-STD-883, Method 3015.8,

Electrostatic Discharge Sensitivity Classification. A similar international HBM standard is JEDEC JS-001. In both JS-001-2012 and MIL-STD-883H, the charged human body is modeled by a 100-pF capacitor and a 1.5-k discharging resistor. During testing, the capacitor is fully charged in a range between 250 V and 8 kV, then discharged through the 1.5-k resistor in series to the device under test.

Because wearables are designed to be worn next to the skin, they are constantly bombarded by static electricity generated by close interaction with the user. Without proper protection, the devices sensor circuits, battery-charging interfaces, buttons or data I/Os could be damaged by ESD levels similar to those generated in the HBM tests. If the wearable device fails, the functions and reliability of the overall network can degrade.

Advanced circuit protection technologies and board layout strategies can safeguard wearable devices and their users. Applying these recommendations early in the design process will help circuit designers improve the performance, safety and reliability of their wearable technology designs and help build a more reliable IoT.

I/O I/O I/O I/O

Unidirectionaldiode configuration

Back-to-back (bidirectional)diode configuration

TVS diodes come in unidirectional or bidirectional (back-to-back) configurations. Unidirectional diodes are typically used for dc circuits as well as digital circuits. Bidirectional diodes are used in ac circuits or any that may include a signal with a negative component exceeding -0.7 V.

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Despite their small outline, todays TVS diode devices perform well without compromising ESD protection.

One example of TVS diodes small enough for use in wearables: the Littelfuse SP3022 Series. These are 0.35-pF, 20-kV bidirectional (back-to-back) discrete diodes able to absorb repetitive ESD strikes over the maximum level specified in the IEC61000-4-2 international standard. The back-to-back configuration provides symmetrical ESD protection for data lines in the pretense of ac signals. Their 0.35-pF loading capacitance makes them practical for protecting high-speed data lines. The device comes in a 0402 footprint and a 0201 flip chip.

BIG ESD PROTECTION, SMALL PACKAGEOne problem with designing protection for wearable circuits is that wearable electronics are small and getting smaller. In the past, it took large diode structures in large packages (for example, 0603 [with a footprint of about 1.6 0.81 mm] and 0402 [about 1.0 0.8601-mm footprint]) to protect against ESD and realize low clamping voltages. But there have been steady improvements in wafer fabrication processes and back-end assemblies that now make it possible to get serious ESD protection in a small form factor. For example, consider the general-purpose 01005 transient voltage suppression (TVS) diode from Littelfuse. It sits in a package having an outline measuring 0.45 0.24 mm and can withstand 30 kV contact discharge (IEC 61000-4-2). It also has a dynamic resistance value of less than 1 .

To see why robust ESD protection is important, again consider the HBM. It specifies test levels beginning at 250 V, but most

application designers ensure their equipment meets at least Level 4 of the IEC 61000-4-2 test standard (8 kV contact, 15 kV air discharge). In many portable devices and wearables, the contact discharge design level is being raised to 15 or 20 kV, with some companies setting it as high as 30 kV. Compact ESD devices are robust enough to meet these demanding conditions.

Use of modern ESD technologies can save a lot of circuit board space. For example, the most common discrete form factor for TVS diodes is the SOD882 package, which has an outline of 1.0 0.6 mm. Moving to a device having a 0201 form factor (0.6 0.3 mm) takes up only 30% of the board area. Furthermore, a device having a 01005 outline (0.4 0.2 mm) brings an 85% space savings compared to the SOD882 package.

Despite their small outline, todays TVS diode devices perform well without compromising ESD protection. In fact, discrete semiconductors with a small form factor can have the same level of ESD protection (30 kV contact

CIRCUIT PROTECTION CONNECTION

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Multi-diode arrays are increasingly housed in super-small packages. An example is the Littelfuse five-channel, bidirectional (back-to-back) SP1012 Series TVS diode array. It houses five ESD diodes in a 0402-size flip-chip package that normally holds just one. Its dynamic resistance is a low 0.48 , and it permits a back-to-back 6-V standoff.

discharge) and clamping performance (dynamic resistance < 1 ) as their larger counterparts (for example, SOD323 and SOD123). However, the small size of the component may present manufacturing challenges. At 0.4 0.2 mm, the 01005 package will need well-designed board treatments, such as solder pads and thick stencils, to ensure the component does not slide or tombstone during the reflow solder process.

SELECTION AND CONFIGURATIONA few key points about the selection and configuration of TVS diode technologies will help design engineers optimize their wearable designs.

Know when to choose unidirectional versus bidirectional diodes. TVS diodes come in unidirectional or bidirectional (back-to-back) configurations. Unidirectional diodes are typically used for dc circuits, including pushbuttons and switches, as well as digital circuits (low-voltage differential signaling). Bidirectional diodes are used in ac circuits, which may include any signal with a negative component greater than -0.7 V. These circuits include audio, analog video, legacy data ports and RF interfaces.

Whenever possible, design engineers should choose unidirectional diode configurations because they perform better during negative-voltage ESD events. During these discharges, the clamping voltage will be based on the forward bias voltage of the diode, which is typically less than 1.0 V. In contrast, a bidirectional diode configuration provides a clamping voltage during a negative strike that is based on the reverse breakdown voltage, which is higher than the forward bias of the unidirectional diode. Thus, the unidirectional configuration can dramatically reduce the stress on the system

during negative strikes.Position diodes judiciously. Most

wearable designs do not need TVS diodes on the PCB at each integrated circuit pin. Instead, the designer should determine which pins have exposure to the outside of the application where user-generated ESD events are likely. If the user can touch a communication/control line, it could become a path for ESD to enter the integrated circuit. Typical circuits prone to compromise this way include USB, audio, button/switch control and other signal lines. Adding these discrete protection devices will take up board space, so it is important to get devices that fit in small 0201 or 01005 outlines. For some wearable applications, space-saving multi-channel arrays are available. Regardless of package style, the ESD suppressor should sit as close as possible to the ESD source. For example, protection for a USB port should sit close to the USB connector.

Keep traces short. Trace routing is important in the design of TVS diode protection for integrated circuit pins. Unlike lightning transients, ESD does

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CIRCUIT PROTECTION CONNECTION

TVS diodes now come in small packages compatible with the cramped quarters that typically define space available for electronics in wearable devices.

not unleash a large amount of current for long durations. To handle ESD, it is important to move the charge from the protected circuit to the ESD reference as quickly as possible.

The length of the tracefrom the signal line to the ESD component and from the ESD component to groundis the overriding factor, not the width of the trace to ground. The trace length should be as short as possible to limit parasitic inductance. This inductance will result in inductive overshoot, which is a brief voltage spike that can reach hundreds of volts if the stub trace is long enough. Recent package developments include DFN outlines that fit directly over the data lanes to eliminate the need for stub traces.

Understand HBM, Machine Model (MM) and Charged Device Model (CDM) definitions. In addition to HBM, MM and CDM are test models for characterizing how well ICs running the portable device or wearable withstand ESD. Many semiconductor makers consider MM to be obsolete. It tends to track HBM in terms of robustness and in failure modes produced, though some producers still employ it. CDM is another alternative to the HBM. Instead of simulating the interaction between a human and an IC, the CDM simulates an IC sliding down a track or tube, then touching a grounded surface. Devices classified according to CDM are exposed to a charge at a given voltage level, then tested for survival. If the device still functions, it is tested at the next level and so on, until failure. CDM is standardized by JEDEC in JESD22-C101E.

Chips that include the processor, memory and ASIC would all be characterized with one or more of these models. Semiconductor suppliers use the models to ensure the robustness of the circuits during manufacturing. The current trend is for suppliers to reduce the voltage test levels because doing so saves die space and because most suppliers adhere to excellent in-house ESD policies.

Strict ESD policies benefit the supplier by allowing for lower on-chip ESD protection, but circuit designers end up with a chip that is sensitive to application-level ESD and which must be prevented from failing due to field-level or user-induced ESD. Designers must select a protective device able to protect against intensifying electrical stresses while clamping voltages low enough to protect the highly sensitive integrated circuitry.

WHEN EVALUATING ESD PROTECTION DEVICES, CONSIDER THE FOLLOWING PARAMETERS:1. Dynamic resistance: This value is a measure of how

well the diode will clamp and divert the ESD transient to ground. It helps determine how low the resistance of the diode will be after it switches on. The lower the dynamic resistance, the better.

2. IEC 61000-4-2 rating: The TVS diode supplier determines this value by increasing the ESD voltage until the diode fails. The failure point characterizes the robustness of the diode. For this parameter, the higher the value, the better. A growing number of Littelfuse TVS diodes can reach as high as 20 and 30 kV contact discharge, which far exceeds the highest level of the IEC 61000-4-2 (Level 4 = 8 kV contact discharge).

As the wearable market continues to grow, so too does the need for circuit protection. In fact, it is more important than ever to consider ESD protection and proper board layout practices early in the design process. Circuit protection devices, such as TVS diodes, can help protect the sensitive integrated circuitry inside wearable devices to maintain the value proposition of the IoT ecosystem. REFERENCES

Littelfuse littelfuse.com


1 mm

1 mm

Littlefuse_EE_IoT_Vs3.indd 21 9/14/15 10:32 AM

The IoT and connected highways

MATT VAN DAM Laird Telematics & M2M Business Unit

Dedicated short-range

communication techniques

could usher in connected

cars and safer driving.

C ars are getting more intelligent technology every year. Soon, that technology will let vehicles communicate interactively and share critical information. One result: fewer fender-benders. When the traffic in front of you slows dramatically, the vehicles ahead will signal to yours and alert you to the dramatic change in speed.

But this is only the beginning. Your vehicle may soon alert you to approaching fire trucks, traffic congestion or even potholes. Through smartphones, IoT-connected vehicles may communicate maintenance issues like tire pressure, fuel level or the need for new antifreeze, before these become serious problems.

Vehicles in the IoT wont just connect to other vehicles. Traffic lights, cross walks and even the road itself could provide real-time information to make your trip safer and more efficient. This kind of connectivity also enables Internet browsing; passengers can start shopping before they hit the store or entertain themselves during a longer ride.

Automotive manufacturers and technology companies are now testing this type of connectivity. In fact, the noted industry analyst firm Gartner is predicting more than a quarter-billion connected carsabout one in five vehicles worldwidewill be on the road by 2020. And the cellular phone company Verizon shows an 83% growth year-over-year for the IoT market in transportation and distribution.

A CRITICAL ELECTION CYCLE In about 18 months, the U.S. will have a new president. He or she will have an opportunity to help convert the information superhighway into a real American connected superhighway, where cars, trucks, pavement, infrastructure and related traffic systems will talk with each other to enhance auto safety and efficiency.

Thats because the next president will likely appoint a new chair and five commissioners of the Federal Communications Commission when their five-year terms expire in 2017 and 2018. Ditto for the U.S. Secretary of Transportation, a presidential appointee and member of the presidents cabinet, who oversees the Federal Highway Administration and the National Highway Traffic Safety Administration.

Together with the president and Congress, theyll play a crucial role in shaping the future of Americas smart highway system. One challenge

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Allegros solutions are extremely robust, handling wide ambient temperature ranges and input/output operating conditions. Design focus is applied to faultmode survival and recovery. It produces industry-leading packaging for enhanced thermal performance.

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theyll face is the fact that network-connected cars and highways will operate in complex radio frequency (RF) environments. Robust end-to-end infrastructure that enables immediate processing of life-critical, actionable data and greater data security will be a necessity.

This infrastructure will also require sophisticated antenna technology, high-performance radios, robust software, bandwidth and excellent coverage, ensuring vehicles stay connected with no blips or outages.

One network technology that can provide this kind of performance and coverage is called dedicated short range communication (DSRC). DSRC is based on the IEEE 802.11 standards used for WiFi, but its specifically focused on meeting the requirements for highway safety. (Its physical layer is defined by the IEEE standard 802.11p, an extension to 802.11 wireless LAN medium access layer [MAC] and physical layer [PHY] specification.) Its a good candidate for the highway environment because it enables direct communication with other systems on the roadvehicle-to-vehicle (V2V), vehicle-to-infrastructure (V2I), and vehicle-to-everything (V2X)thus requiring no cellular networks.

It is useful to review some of the technical aspects of these communication systems. DSRC uses 75 MHz of spectrum in the 5.9-GHz

Vehicles in the IoT wont just connect to other vehicles. Traffic lights, cross walks and even the road itself could provide real-time information to make trips safer and more efficient.

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CONNECTED HIGHWAYS

Street lights could adjust their brightness automatically for optimal lighting on a cloudy afternoon or during a rain storm.


band that the FCC allocated for intelligent transportation systems. DSRC messages and messaging schemes are defined in the SAE J2735 standard. This SAE Standard specifies a message set and its data frames and data elements. The most fundamental message is the basic safety message (BSM). All vehicles send it periodically. It contains parameters defining a vehicles dynamic state, which are critical for safety applications, such as speed, heading and location.

DSRC operates over the Wireless Access in Vehicular Environments (WAVE) communication system. This standard is an amended version of the IEEE 802.11 standard (the common WiFi standard). The Federal Communications Commission (FCC) allocated a frequency band for DSRC from 5.85 to 5.925 GHz. DSRC divides this range into seven 10-MHz channels and a 5-MHz guard band. It uses orthogonal frequency-division multiplexing (OFDM) with four pilot and 48 data sub-carriers for each channel.

Of the seven channels, one is a control channel (CCH) used for safety applications. The other six channels, called service channels (SCHs), will be used for infotainment or commercial applications to get the cost of this technology down. Vehicles will synchronize the switching between the CCH and one or more of the SCHs in a way that prevents the loss of safety-related messages. A synchronization interval (SI) contains a CCH interval (CCI), followed by a SCH interval.

V2V is a communication scheme designed to let automobiles talk to each other. The systems also use the 5.9-GHz band. V2V is also known as VANET (Vehicular ad hoc network) and is currently in active development by major automakers. It is a variation of MANET (Mobile ad hoc network), a continuously self-configuring, infrastructure-less network of mobile devices where the nodes are vehicular.

In V2V, vehicles exchange information about location, speed, acceleration and braking. Because V2V allows this data

exchange ten times per second, vehicles will be able to calculate a hazard risk within about 300 m and alert the driver or even execute collision-avoidance actions. Drivers will be able to see, hear and even feel the hazard signals through vibration of the seat.

DSRC also includes complex circuitry and software enabling it to create a unique identity for each vehicle to protect

the operators privacy and the systems data security. In addition, DSRC schemes will build in security measures as defined by a family of standards called IEEE 1609. They also provide for a resource manager that manages communication between remote applications and vehicles and communications through multiple channels. This standard also allows for both vehicular onboard units (OBU) and roadside units (RSU). RSUs act like wireless LAN access points and can provide communications with infrastructure. Finally, a third type of communicating node called a Public Safety OBU (PSOBU) is a vehicle able to provide services normally coming from an RSU. PSOBUs are mainly police cars, fire trucks and ambulances in emergency situations.

In outlying or rural areas, DSRC-equipped vehicles also would act as their own hotspots, relaying signals to each other, so there would be no dead-zones as long as vehicles are on the road.

Unlike WiFi, DSRC is designed to work with moving vehicles and to adjust for environmental challenges related to RF signal reflection, temperature variations, and high vibration. The technology is currently being tested and developed with the U.S. Dept. of Transportations Test Bed Program on roads in Michigan and other states.



DSRC is based on the IEEE 802.11 standards used for WiFi. Its physical layer is defined by the IEEE standard 802.11p, an extension to 802.11 wireless LAN medium access layer (MAC) and physical layer (PHY) specification. It enables direct communication with other systems on the roadvehicle-to-vehicle (V2V), vehicle-to-infrastructure (V2I), and vehicle-to-everything (V2X)thus requiring no cellular networks.

DSRC in action

IoT ADVANTAGESWith the resources of the IoT, the environment around the road can also play a role in managing the safety of motorists. DSRC antennas and devices can provide real-time data, letting vehicles detect motorcycles, cyclists and even pedestrians blocked from the drivers view. The same technology could let traffic command centers monitor and re-route traffic around potential dangers. Street lights could adjust their brightness automatically for optimal lighting on a cloudy afternoon or during a rain storm. And the process of merging into traffic from a blind turn becomes less of a guessing game when the connected parking garage alerts you to approaching traffic around the corner.

There are benefits besides safety. With the IoT in place, in-vehicle navigation data would be more accurate with near real-time updates. Connected vehicles could share fuel efficiency data so drivers could get more miles per gallon by selecting the right routes.

A connected highway could also keep in touch with local governments. Maintenance crews could be alerted to potholes or icy patches when a connected car detects

them. And circling for a parking spot may eventually be a thing of the past. Parking lots could provide near real-time data about the number of open parking spaces and directions to their location.

A standardized and regulated IoT environment, however, will only come after a great deal of innovation and collaboration among the automotive and networking industries. It also will require the cooperation and commitment of the new FCC and USDOT appointees, and the support of the next U.S. President.

REFERENCES

Laird Tech, The Connected Highway lairdtech.com/solutions/white-papers/connected-highway

CONNECTED HIGHWAYS

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Industrial power for the Internet of Things

SOL JACOBSTadiran Batteries

Many devices on the Industrial IoT will need rugged

primary and rechargeable lithium batteries to provide

reliable, long-term power.

N o question there will be a lot of remote wireless devices on the IoT. Many of them will be powered either by primary lithium batteries or energy harvesting devices combined with rechargeable batteries or supercapacitors. Here are a few ideas about battery chemistries that make sense for power scenarios likely to arise in industrial IoT applications.

A wireless device intended for long-term deployment and drawing a low average daily current could be a candidate for primary bobbin-type lithium thionyl chloride (LiSOCL2) batteries. LiSOCL2 chemistry is the predominant choice for remote wireless applications because of its exceptionally high energy density (1,420 Wh/l volumetric densities are widely available, compared to about 100 Wh/l for lead acid), high capacity, wide temperature range, and low annual self-discharge rate.

Certain bobbin-type LiSOCL2 batteries can deliver a self-discharge rate of less than 1% per year; batteries can operate for up to 40 years in situations where the annual self-discharge of the battery exceeds the annual power consumption of the device. The smart grid is a prime example of where bobbin-type LiSOCL2 batteries have been deployed in an industrial IoT environment. For nearly 30 years these batteries have powered endpoint terminals of metering devices that communicate to central databases. Power meters are increasingly becoming smart meters. They now interface with

DESIGNWO

RLDONLINE

.CO

MInternet of Things

In the CattleWatch system, smart collars placed on cattle all communicate with hub collars placed on a select few of the herd. The hub collars communicate with Iridium satellites serving as a link to the cloud. All the devices carry industrial grade lithium batteries for power. Ranchers typically get aggregated data on their smartphones.

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the IoT to provide real-time information and alerts about consumption patterns. To conserve energy, these wireless devices operate mainly in a dormant state, drawing little or no energy. They periodically take data, but only awaken if they note certain data parameters. Careful control of energy consumption lets these wireless devices operate maintenance-free for decades.

The main limitation of standard LiSOCL2 chemistry is high passivation arising from a low-rate design. In LiSOCL2 cells, thionyl chloride is a liquid. Metal lithium touches the thionyl chloride and will slowly oxidize out lithium chloride. The lithium chloride layer produced on the surface of the metal lithium tends to prevent lithium from reacting with thionyl chloride. This phenomenon is passivation. The passivation takes place slowly, but the speed of passivation is higher at higher temperatures and is more pronounced over longer time periods.

The passivation prohibits these cells from delivering high current pulses. This issue can be addressed by combining a standard LiSOCL2 cell with a patented hybrid layer capacitor (HLC). The standard LiSOCL2 cell delivers low background current to power the device in its standby mode, while the HLC stores and delivers the high pulses required when the device is in its active mode of data interrogation and transmission.

An alternative involves the use of supercapacitors, also known as ultracapacitors or electric double layer capacitors (EDLCs), which store energy in an electrostatic field rather than in a chemical state. Supercapacitors are primarily used to provide memory back-up power for mobile phones, laptops and digital cameras. This technology has certain inherent drawbacks, including short-duration power, linear discharge characteristics that do not allow for use of all the available energy, low capacity, low energy density, high self-discharge (up to 60% per year), and the need for cell balancing when supercapacitors link in series. Supercapacitors also have crimped seals that may leak and have not been proven to deliver long life.

CONSUMER GRADE VERSUS INDUSTRIAL GRADE Some industrial IoT applications may be well suited for energy harvesting. Energy harvesting (also called energy scavenging) refers to the process of deriving energy from external sources (such as solar power, thermal energy, wind energy, salinity gradients and kinetic energy). Harvested energy is usually used to power wireless autonomous devices. The decision to use an energy harvesting device depends on factors that include the reliability of the device and its energy source; the expected operating life of the device; environmental requirements; size and weight considerations; and total cost of ownership.

An energy harvesting device generally contains five basic components: sensor, transducer, energy processor, microcontroller and optional radio link. The sensor detects and measures environmental parameters such as motion, proximity, temperature, humidity, pressure, light, strain vibration and pH. The transducer and energy processor work in tandem to convert, collect and store the electrical energy in either a rechargeable lithium battery or a supercapacitor. The microcontroller collects and processes the data. The radio link communicates with a host receiver or data collection point. The energy harvested is often relatively small, especially for devices that draw only a few microamps of current daily.

Energy harvesting devices are typically paired with rechargeable lithium-ion (Li-ion) batteries that store harvested energy. Consumer grade Li-ion cells are reasonably inexpensive and widely available, but have a life expectancy of less than five years and 500 recharge cycles. They also only work over a moderate temperature range of -10 to 60 C, so they dont work well for long-term deployment in extreme environments.

Industrial grade Li-ion batteries are a better choice if the wireless device is intended for use in remote, inaccessible locations. Industrial Li-ion cells can operate for up to 20 years and handle 5,000 full recharge cycles. They also work over a temperature range of -40 to 85 C and can deliver high current pulses (5 A for an AA-size cell). These industrial grade Li-ion cells also feature glass-to-metal hermetic seals, whereas consumer rechargeable batteries use crimped seals more prone to leak.

As a general rule, industrial grade Li-ion batteries make sense where the expense of battery replacement far exceeds the cost of the battery itself. This can be confirmed by calculating the total lifetime cost of the industrial grade Li-ion battery versus a consumer grade Li-ion battery.

For an example application, consider wireless solar-powered parking meters. Made by the IPS Group, they incorporate state-of-the-art features that include multiple payment system options, access to real-time data, integration to vehicle detection sensors, user guidance and enforcement modules, and connections to a comprehensive web-based management system.

PV panels in the meter gather solar energy, which then gets stored in an industrial grade rechargeable Li-ion battery. The rechargeable battery can deliver the high pulses required to initiate two-way wireless communications.

Another example of an industrial IoT application is CattleWatch, which places solar-powered hub collars and solar-powered collar units on cattle. All collars communicate with the hub collars through a wireless

Tadiran_EE_IoT_Vs3.indd 28 9/14/15 11:03 AM

INDUSTRIAL POWER


The M5 single-space parking meter developed by the IPS Group uses an industrial grade rechargeable Li-ion battery to store energy harvested by built-in solar cells. The meter mechanism is wirelessly networked to a management system in the cloud.

mesh network. Hub collars communicate to the cloud through Iridium satellites. Ranchers get real-time updates on daily animal behavior, including herd location, walking time, grazing time, resting time, water consumption, in-heat condition and other health events. Ranchers also receive instant notification if potential threats arise from predatory animals or poachers.

Energy harvested by PV panels in CattleWatch units gets stored in industrial grade Li-ion rechargeable batteries. The batteries were chosen over supercapacitors because they were

significantly lighter and smaller, and thus more comfortable for the animals to wear.

Every application is special and specific requirements dictate the best power supply. When long-term reliability is essential, an industrial grade battery generally makes more economic sense than a consumer gradeone.

REFERENCES

Tadiran Batteries tadiranbat.com

Tadiran_EE_IoT_Vs3.indd 29 9/11/15 6:11 PM


Real-time operating systems for wearable devices in the IoT

WARREN KURISU Mentor Graphics

Operating systems and the way they handle tasks can

make or break applications such as activity trackers and

fashion electronics.

T he wearables industry is still in its early stages of development. The financial firm Morgan Stanley estimates that the wearables market could become a $1.6 trillion business in the next few years. But a lot of software work will have to go into realizing these trends. A full-featured, real-time operating system (RTOS) can help get smart wearable products up and running quickly.

The physical form factor of most wearable

devices leaves little room for the electronics. A

wearable device can pack an amazing array of peripherals

for its size, but memory capacity is the one area where geometry cant be out-maneuvered. An RTOS can help minimize memory demands in wearables. The RTOS itself can have a small footprint

Breakthroughs in optimizing power efficiency let the Omate Smartwatch operate up to five days (standby mode) on a single battery charge.

and provide a deterministic behavior that helps keep code compact. But it must also scale down to a minimal size in both code and data requirements to survive at the lowest end of the device spectrum. This same RTOS must also be able to scale up to the most full-featured range of services.

Wearables, for the most part, are extremely small. They often use an 8-bit MCU clocked at less than 25 MHz, with only 8 K of memory. Low-power ARM-based processors are good candidates for wearable devices because of their small form factor and minimal power requirements. Recent products taking the ARM approach include the Pebble watch and the Omate Racer Smartwatch.

Omate is a hardware and software design company. Its Racer Smartwatch is a stand-alone telecom mobile device that works with numerous iOS and Android applications using Bluetooth connectivity to a smartphone. Users can send and receive incoming calls, social media updates, messages and reminders, among other notifications.

The Racer Smartwatch carries an ARM7 MediaTek Aster SoC, the industrys smallest wearable SoC. The MediaTek chipset relies on the Nucleus RTOS from Mentor Graphics for power management and wireless programming. Nucleus can scale voltage and frequency for reduced power consumption of a single or multiple operating system platform, maximizing cycles-per-watt to conserve power.

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Industry average

Vin=24V,Vout=24V,Iout=0.833A

[email protected]

TEL: 978-567-9610

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Bluetooth/BLE and WiFi, up to huge mobile cellular networks. This is an area where technology, protocols and options change rapidly. Similarly, solutions currently deemed to be too expensive today can easily become the economical standard tomorrow.

Communication technologies can change over the lifetime of a wearable device, or even during the development cycle. The operating system environment can help handle these changes to minimize the impact on applications.

RTOSs have been around for years, and countless embedded devices have employed them. The typical RTOS incorporates basic capabilities such as a kernel, scheduler, file system, connectivity and graphics support. An RTOS for wearable devices also has stringent requirements in three other critical areas: scalability, space partitioning and comprehensive power management.

One advantage of an RTOS environment is the ability to treat the RTOS application programming interface (API) as the target machine. This lets software personnel develop applications to that specification. Beneath the RTOS, middleware and device drivers handle the hardware directly. So an application can adapt to the particular details of the a specific product version by working with the API. This can happen through dynamic evaluation of the features at runtime, or through selective build options during compilation and linking.

The Nucleus RTOS lets applications work with a wide variety of peripheral combinations. It also lets developers transport applications and use them in different processor variations, families, and architectures. Moreover, it lets a reduced feature version of an application work on a single-chip MCU and behave much the same way as a full-featured version on a high-performance MPU platform.

SPACE DOMAIN PARTITIONING Space domain partitioning created through the use of light-weight processes can make systems more reliable and prevent one subsystem from bringing down another. The idea is to let limited memory resources be re-used by loading and unloading memory modules based on the application needs. These features are normally found only in high-end or general-purpose OSs that use cores containing memory management units (MMUs) for partitioning and virtualizing memory. The Nucleus RTOS brings these functions to Cortex M devices that do not incorporate an MMU. In other words, it can handle space

Hardware Platform

Nucleus OS

Static Application

Kerner-modeProcess 1

Kerner-modeProcess 2

Kerner-modeProcess m

User-modeProcess 1(e.g. Qt)

User-modeProcess 2

User-modeProcess n

The Nucleus real-time operating system employs a light-weight approach to a process model. The MPU in the ARM Cortex-M3/M4-based SoCs on which it runs can be used for spatial domain partitioning without the need (or overhead) to virtualize memory. Processes can load directly from ROM or Flash into memory. And with pre-linked embedding, processes can execute in situ in Flash, a feature commonly necessary in MCUs with limited RAM.

With built-in power management and connectivity capabilities, the RTOS helps with power-sensitive wireless communications applications. Nucleus also applies a system power state for each of the peripherals in the SoC. This lets the SoC independently control the power to different blocks, modules or peripherals, allowing various applications to run simultaneously.

More complex designs often include feature-rich SoCs clocked in the hundreds of megahertz and megabytes of memory. These hybrid systems may include special-purpose processors and multiple application and/or microcontroller cores. The more complex SoCs often require a graphical user interface (GUI) and wireless connectivity to the Internet or cloud. It takes a full-featured RTOS to power these more complex designs.

The compelling difference between wearables today and devices from a few years ago is the greater availability of wireless connectivity options. Wireless connectivity spans the range from Near Field Communication,


REAL-TIME OS


domain partitioning without the overhead of virtualizing memory. Processes can load from a file system to memory or run directly in RAM or Flash (XIP).

RTOSs that are equipped to handle spatial partitioning can configure the MPU at run time to establish memory regions in both kernel and user space. APIs can be used to load processes at runtime or based on the use-case during execution.

Battery life is obviously critical for wearables. Modern processors contain numerous power saving capabilities. Examples include idle modes, sleep modes, dynamic voltage frequency scaling (DVFS) and hibernation modes. If the underlying operating system does not have a framework to take advantage of the low-power features in the silicon, the developers must generate the code to do so. The amount of code required creates more complexity and can add to code bloat.

Power saving features are built into the silicon. However, their use becomes complicated in the absence of an operating system designed to handle them. For instance, consider the process of implementing a simple power-saving feature such as lowering the frequency. Before the processor can shift frequency, software must know the state of each peripheral device. Additionally, it must know if each peripheral device can operate at the new lower frequencysome may not. Software must also know how long each active device can be taken offline to effectuate the frequency shift without losing any data. Some devices can only go offline for a short period, so they must be taken offline last and brought back online first. And after the frequency shift, devices like the UART will need their baud rate reset.

A view of the Nucleus RTOS functional makeup shows the Device Manager at the center of a power management framework. The Device Manager coordinates the transition of all devices during a change to a low-power state.

Obviously, the management of all these details takes a significant coding effort in the absence of an RTOS with an API for power management. But with an API available, a frequency shift can happen with a single API call. All in all, a power management framework provides a way for API calls to control all system devices.

The power management framework approaches the conservation of power use from four directions: 1) system states are used to control peripheral power; 2) dynamic voltage scalingbasically, reducing the operating voltagefocuses on the entire system; 3) idle power management prevents expending energy without a specific goal; and 4) hibernate/sleep modes that let the system go off-line during long periods of inactivity.

A power management framework lets software developers write code to conserve power without creating code bloat or increasing the footprint. A power management framework also lets software developers plan for power specifications early in the design cycle. The resulting code can be tested throughout the development

process to ensure power consumption remains at targeted levels.

Finally, wireless connectivity is important for any IoT application. RTOSs, such as Nucleus, include facilities for handling wireless standards such as WiFi, Bluetooth/BLE, and 802.15.4. Additionally, adaptation layers like 6LoWPAN (IPv6 over Low power Wireless Personal Area Networks)provide routeable addressing to IoT devices based on IPv6, the most recent version of the Internet protocol. In short, RTOSs will need to support numerous wireless schemes and IoT protocols, as well as methods of integrating wireless devices into the cloud.

REFERENCES

Mentor Graphics, Nucleus RTOS mentor.com/embedded-software/nucleus/

Wikipedia page for real-time operating systems en.wikipedia.org/wiki/Real-time_operating_system

Wikipedia page for Nucleus RTOS, en.wikipedia.org/wiki/Nucleus_RTOS


SoMs speed the move to the Industrial Internet of Things

ERIC MYERSNational Instruments

Systems-on-modules and platform approaches can

help keep IIoT efforts from getting lost in the weeds of

interfacing and hardware development.

E ngineers who design equipment for the Industrial Internet of Things (IIoT) will likely face a number of technical challenges. One of the most significant is in developing systems that are adaptable and that can scale with the IIoT.

To get a feel for the problem, consider the aircraft maker Airbus and its experiences developing a Factory of the Future. This is a long-term research and technology project that employs emerging computing and communications technologies to build aircraft faster, more flexibly and with higher quality. Airbus plans to develop many systemssuch as smart tools, inspection devices and roboticsthat will connect and work in harmony to improve the overall manufacturing process.

Like most traditional design firms, Airbus began by designing its concepts from the ground up. It eventually recognized that connecting all of these systems in a smart way is not trivial due to the many communication mechanisms and protocols involved in an IIoT network.

As Airbus learned, the task of building a complete system from the ground up takes a substantial amount of time. During the initial design, teams spend most of their time making

An example of a system on module (SoM) device. This one, from National Instruments, employs a real-time version of Linux and a programmable SoC.


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SOMs SPEED THE MOVE

components work together. Only a small amount of time is spent developing the special functions of individual nodes.

Another challenge lies in scaling these systems to grow with the expanding IIoT. When such a system is first deployed, it generally works well. But nodes in the network must be able to change and adapt and new devices are constantly added. Its not unusual for new devices or functions to force a redesign of the network from the ground up. For example, were Airbus to add a new robotic system on its factory floor, the move would force a redesign of other systems to support the proprietary protocol involved.

Its also not uncommon to see teams developing systems using multiple off-the-shelf subsystems, sometimes developing parts themselves, then using off-the-shelf devices where appropriate. In machine control, for example, many systems today add health monitoring capabilities using off-the-shelf subsystems.

This approach speeds development, but off-the-shelf subsystems are typically closed and fixed. Closed architectures tend to have a limited ability to expand. If they can expand at all, it is generally though one or two expansion ports that use a proprietary design, perhaps requiring a license fee from the manufacturer. And it may take technicians with specialized tools or training to install any enhancements. The proprietary nature of closed designs tends to limit the amount of information they can share over the network. Moreover, data that cant be communicated through an open standard interface cant be analyzed by other devices, eliminating one of the benefits of the IIoT.

The way around this difficulty in the IIoT is by deploying a network of things flexible enough to evolve and adapt. Teams need an evolved approach that focuses on the innovation within the application itself, not on hardware or software. This is known as a platform-based approach, one emphasizing systematic reuse of software and compatible hardware, intended to reduce development risks, costs and time to market.

One example of a platform technology that is becoming widely used is system on module (SoM) and computer on module (CoM). For hardware developers, an SoM provides the processing, memory, peripherals and I/O elements needed in any IIoT system. For software developers, an SoM comes with anything from a board support package (BSP) to a complete software suite fully supporting the hardware and connectivity to other systems.

In the case of Airbus and its Factory of the Future, the firm decided to adopt NI SoM, providing

core hardware components along with a software suite to support the board. Airbus estimates that switching to this approach cut its development effort by a factor of ten.

Among the entities developed for the Airbus Factory of the Future are smart tools. A given airplane subassembly has about 400,000 fastening points that must be tightened. Human assemblers handle the task using over 1,100 different tightening tools. The operator must follow a list of steps and verify the proper torque law settings for each

location. To eliminate possibilities for error, a smart tightening tool uses machine vision to understand the tightening task at hand and automatically set the torque. The outcome of the task gets recorded in a central database. This lets production managers review procedures and processes during quality control and certification.

With a platform-based approach and growing technology though, these teams will be able to efficiently develop the IIoT, such as Airbus with the NI SoM.

REFERENCES

Airbus Factory of the Future case history sine.ni.com/cs/app/doc/p/id/cs-16246

LabVIEW overview www.ni.com/labview

Systems on Modules sine.ni.com/nips/cds/view/p/lang/en/nid/212787

Its also not uncommon to see teams developing systems using multiple off-the-shelf subsystems,

sometimes developing parts themselves, then using

off-the-shelf devices where appropriate.

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Big future for cyber-physical manufacturing systems.

JAY LEEUniversity of Cincinnati

BEHRAD BAGHERI NSF I/UCRC for Intelligent Maintenance Systems (IMS)

The real value of the

IoT for manufacturers

will be in the analytics

arising from cyber-

physical models of

machines and systems.

A couple decades ago, smart appliances only belonged to sci-fi movies. But rapid advances in technology made it practical to connect sensors and physical assets to networks. We have now progressed to the Internet of Things (IoT) where embedded sensors are in charge of collecting data from ever more physical assets. This process is generating a massive amount of data.

Unfortunately, the technology for storing such a gigantic amount of data

is inadequate to cover all the data being generated daily. Similarly, the analytical approaches in wide use are not mature enough to intelligently and efficiently process all the generated data. This problem has been known as the Big Data challenge. To understand its magnitude, consider the 2014 annual report on Big Data by EMC and IDC, which found in 2013 that the digital universe generated 4.4 zettabytes (1 ZB = 1 billion TB) of data. In that same year, only 7% of 187

A cyber-physical system is characterized by a physical asset, such as a machine, and its digital twin; basically a software model that mimics the behavior of the physical asset. In contrast, the IoT in common parlance is generally limited to the physical assets, not their digital models.

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Documents

Design World/EE Network - IoT Handbook