Fundamentals of Internet of Things for Non-Engineers

Rebecca Lee Hammons, Ronald J. Kovac, Rebecca Lee Hammons, Ronald J. Kovac

• Publisher: Auerbach Publications
• Year: 2019
• Print ISBN:
  9781138610859
• eBook ISBN:
  9781000007176
• Topic: Computer Science
• Subtopic: Computer Networking
• Index: Computer Science

The IoT is the next manifestation of the Internet. The trend started by connecting computers to computers, progressed to connecting people to people, and is now moving to connect everything to everything. The movement started like a race—with a lot of fanfare, excitement, and cheering. We're now into the work phase, and we have to figure out how to make the dream come true.

The IoT will have many faces and involve many fields as it progresses. It will involve technology, design, security, legal policy, business, artificial intelligence, design, Big Data, and forensics; about any field that exists now. This is the reason for this book. There are books in each one of these fields, but the focus was always "an inch wide and a mile deep." There's a need for a book that will introduce the IoT to non-engineers and allow them to dream of the possibilities and explore the work venues in this area. The book had to be "a mile wide and a few inches deep." The editors met this goal by engaging experts from a number of fields and asking them to come together to create an introductory IoT book.

Fundamentals of Internet of Things for Non-Engineers

• Provides a comprehensive view of the current fundamentals and the anticipated future trends in the realm of Internet of Things from a practitioner's point of view
• Brings together a variety of voices with subject matter expertise in these diverse topical areas to provide leaders, students, and lay persons with a fresh worldview of the Internet of Things and the background to succeed in related technology decision-making
• Enhances the reader's experience through a review of actual applications of Internet of Things end points and devices to solve business and civic problems along with notes on lessons learned
• Prepares readers to embrace the Internet of Things era and address complex business, social, operational, educational, and personal systems integration questions and opportunities

IoT ELEMENTS AND ISSUESII

Chapter 5

IoT End Devices

Ronald J. Kovac

Ball State University

Contents

5.1Introduction

5.2Major Sections and Subsections of IoT

5.2.1Sensors—Input

5.2.2Compute/Storage/Networking—The Decision-Making

5.2.3Output—Actuators

5.2.4Services—Logic Underlying All of This

5.3Sensors and Telemetry

5.3.1Criteria for Sensors

5.3.2Management and Control of Telemetry and Telecommand Messaging

5.3.3Sensor Types

5.3.4Smart Sensors

5.3.5Sensor Fusion

5.4Actuators

5.4.1Actuators Overview

5.4.2Actuator Control Signal

5.4.3Energy Sources

5.4.4Actuator Considerations

5.4.5Actuator Types

5.4.6Actuator Examples in the IoT World

5.5Key Criteria for Sensors and Actuators

5.5.1Battery Power

5.5.2Environment

5.5.3Local Processing

5.5.4Connectivity

5.5.5Security

5.5.6Cost

5.5.7Ease of Integration

5.5.8Accuracy

5.6Summary

5.7Case Study

5.8Discussion Questions

References

Additional Sources

5.1 Introduction

Sensors are the start of the Internet of Things (IoT). Actuators are the end of the IoT. Without cost-effective, accurate, reliable, and secure sensors and actuators, S/A, the IoT could not exist. This is similar to our human existence. We see a blockage on the sidewalk with our eyes (sensors), and we adjust our body to walk around it. The IoT takes this beyond our five senses (sight, smell, sound, taste, and tactile) to things we cannot sense (infrared and ultrasonic) and with accuracy that we can only imagine (98.6°F body temperature as measured by a thermometer).

In this chapter, we will explore various types of S/A that are and will be used in the IoT space. We will also look at the various criteria that we must measure and affect and, what is coming down the pike as far as smart sensors go.

We, of course, will close with a case study that looks at the S/A in use in today’s world and then some probing questions to discuss and consider.

5.2 Major Sections and Subsections of IoT

Depending on whom you listen to, IoT can be broken down into numerous parts and sections. For the subject here, we will break IoT into four major sections:

1. Input—The sensors and their telemetry
2. Decision-Making—The compute, storage, and networking that must take place in order for decisions to be made
3. Output—The activators
4. Services—The logic and systems underlying IoT (Figure 5.1)

5.2.1 Sensors—Input

The starting data that permits IoT to exist comes from sensors. These sensors can be standard, they can be smart, or they can be manual. A standard sensor, like your car’s gas gauge, senses one variable. A smart sensor detects multiple variables and makes decisions based on its readings. Finally, a manual sensor is like a light switch—human intervention is necessary. Whatever method, these are the start of the IoT cycle. In this chapter, we will look at various sensors and what they measure in order to create the starting point of IoT. Elements here are often called data sources or IoT things. The data transmitted from sensors is often called telemetry, meaning remote monitoring. Here we create and start the IoT world.

Figure 5.1 Major sections and subsections of IoT.

5.2.2 Compute/Storage/Networking—The Decision-Making

Based on the input from the sensors, decisions get made. The major parts of this decision-making consist of compute, storage, and networking elements. The compute elements do the actual processing of data, similar to your personal computer, and do so with the same architecture as common computers (Intel microprocessors, etc.). The storage elements hold the data before and after processing. For example, we store all the traffic flows for a week and then compute base-predictive scenarios to turn the traffic lights green or red to optimize traffic flow. The networking elements allow all the various devices to talk among themselves within a local system. Included in this decision-making is an area which is coming into prominence, called Big Data analysis. Essentially, this involves analyzing very large data sets to derive patterns and trends. This field is up-and-coming and is nowhere near as simple as it sounds. An in-depth look by the reader is strongly suggested (Figure 5.2).

Figure 5.2 Major sections of the decision-making.

5.2.3 Output—Actuators

Based on the decision made in the previous step, an actuator changes the state of the environment (by turning the heat on, turning a traffic light red, etc.). Be aware, the output of the decision-making could also be in the form of a notification: a note or flag to a human to do something. The human element is often brought into this to assure the proper decisions are being made and to provide a failsafe for the IoT system. Here we act as the end of the IoT system.

5.2.4 Services—Logic Underlying All of This

Services are the software side of IoT that manage the infrastructure; guide the decision-making; and provide scalability, adaptability, portability, and automation. This section also includes the globally interconnected network of the IoT world and any applications that remove the raw processing from the user.

Figure 5.3 is a more complex build out of the IoT world that one would typically see in magazines and books.

5.3 Sensors and Telemetry

Sensors are the start of the IoT world. They measure characteristics for the rest of the IoT systems that think and act upon this data. They detect types of input from the physical environment and are the root of the IoT solution. The signals that the sensors create are often called telemetry. Sensors must comply with the following rules:

• They must be sensitive enough to reliably and accurately measure the noted property (for example—temperature).
• They cannot influence the measured property (such as a temperature sensor that puts out heat).

  

  Figure 5.3 Complex IoT form.

• They must not be sensitive to other properties that can alter the measured property (such as a thermometer that is affected by wind chill).

Most sensors put out a linear function of telemetry, meaning that when temperature changes, they put out a correspondingly lower or higher voltage in a linear fashion (like a line). Sensors adjust the voltage according to the input temperature, or they can change capacitance, resistance or any other electrical property. If a sensor puts out an analog signal, as most natively do, this signal must be digitized in order to be used in digital computers. This function usually happens at or near the sensor itself.

5.3.1 Criteria for Sensors

There are many characteristics of sensors that must be considered before use or application. A few selected characteristics are discussed below:

• Range—Usually a sensor can measure properties only within a predefined and limited range. For example, a thermometer goes up to 110 °F and down to − 10 °F. The selection of the sensor range must be qualified to the use of the sensor.
• Sensitivity—How precisely can the sensor read. Can it read to the 1°F level or to the ¼ °F level? This is often called resolution.
• Nonlinearity—Often sensors measure differently throughout their range of measurement, and some type of correction must be put in to adjust the sensor output. For example, as a thermometer gets hotter, the scale of the output becomes nonlinear. (Refer to Figure 5.4).
• Drift—As the sensor measures its property over time, its characteristics change, and therefore, the measurement characteristics become wrong.
• Reliability—Drift, as discussed above, often happens over time. Reliability is the incorrect nature of a signal that happens during manufacturing of a device or over a period of time. Calibration (comparing the output of the sensor to a known source) can often correct issues with reliability and drift.
• Quantization Error—If the output of the sensor is analog, as it often is, the signal is usually digitized to work in modern digital systems. The translation of analog signals to digital signals is an approximation of the analog signal and therefore prone to errors.

The global market for sensors reached $110.4 and $123.5 billion in 2015 and 2016, respectively. (Rajaram 2017)

The sensor market is expected to increase from nearly $138.8 billion in 2017 to nearly $240.3 billion in 2022 at a compound annual growth rate (CAGR) of 11.8% for 2017–2022. (Rajaram 2017)

Figure 5.4 Linear output of a sensor and digitization.

5.3.2 Management and Control of Telemetry and Telecommand Messaging

To control and manage the stream of information coming from sensors and going to actuators, there are messaging protocols. These messaging protocols control the pace of information flow, the syntax of the flow, and generally manage and provide structure to all the information flow there is for the IoT world. There are many types of messaging protocols for sensors and actuators, and here, we will introduce you to a few of the common ones found these days. These protocols guide the information flow from the sensors.

• MQTT—Message Queuing Telemetry Transport is an ISO Standard. It works on top of the TCP/IP protocol and is often used for remote connections that do not have a lot of information (such as a temperature probe). Therefore, it requires limited network bandwidth which is appreciated. Facebook Messenger used MQTT. https://en.wikipedia.org/wiki/MQTT
  “When I developed MQTT, with my collaborator Arlen Nipper, 17 years ago, I had what I used to call my ‘modest plan for world domination’, which was that one day all devices would connect to TCP/IP, and all of them would talk MQTT.”—Andy Stanford-Clark
  IBM Distinguished Engineer for the Internet of Things (Lewis 2016)
• Advanced Message Queuing Protocol (AmQP)—creates a standard of interoperability between various pieces, parts, and systems. It is open standard based and has a high degree of reliability and security. This is often used to connect servers to servers.
• Extensible Messaging and Presence Protocol (X...

Table of contents

• Cover
• Half Title
• Title Page
• Copyright Page
• Table of Contents
• Preface
• Acknowledgments
• Editors
• Contributors
• SECTION I THE BASICS OF IoT
• SECTION II IoT ELEMENTS AND ISSUES
• SECTION III IoT CASE STUDIES
• Glossary
• Index