Part 1 – Sensing and power

The internet starts or ends with an event: a simple motion, a temperature change, perhaps an actuator moving on a lock. Unlike many IT devices in existence, IoT in a large part is about a physical action or event. It responds to affect a real-world attribute. Sometimes this involves considerable data being generated from a single sensor, such as auditory sensing for preventative maintenance of machinery. Other times, it's a single bit of data indicating vital health data from a patient. Whatever the case may be, sensing systems have evolved and made use of Moore's law in scaling to sub-nanometer sizes and significantly reduced costs. When one talks about the billions of devices in IoT, this is what they are referring to and why there will be billions of devices in reality. This chapter explores the depths of MEMs, sensing, and other forms of low-cost edge devices from a physical and electrical point of view. The chapter also details the necessary power and energy systems to drive these edge machines. We can't take power for granted at the edge. Collections of billions of small sensors will still require a massive amount of energy in whole to power. We will revisit power throughout this book, and how innocuous changes in the cloud can severely impact the overall power architecture of a system.