The key to the IoT (Internet of Things) today is sensors that monitor all kinds of parameters, ranging from motion to current to temperature. These sensors are found everywhere, including smartphones, doorbells, thermostats, vehicles, and appliances, capturing important data that can be shared in real time with users and stored for later retrieval and analysis. These sensors can be integrated with equipment/devices, embedded with processing and communication capabilities, or implemented as standalone devices, where processing and key communication capabilities are pushed to the gateway.

According to IoT Analytics, a market research and intelligence firm, IoT sensors represented a third of all sensors shipped in 2022. The average IoT device now comes with four sensors.  The firm pegged the IoT sensor market at $10.9 billion in 2022 and is projected to grow at a compound annual growth rate of 16% over the next five years.

IoT Analytics has identified five IoT sensor technology trends that will transform the IoT sensor landscape in coming years.

IoT sensors will add computing capacity and improve their ability to detect signals from multiple discrete sensing elements. Often referred to as “smart sensors,” these sensors can perform signal processing and analysis on board instead of just transmitting data to another location for processing. These sensors will in effect become “edge” devices in an IoT network. IoT analytics also predicts that advanced smart sensors will gain AI capability, enabling them to make instant decisions instead of sending the data elsewhere and risk data theft.

Because IoT sensors must be able to operate continuously, battery technologies are inappropriate for these devices. Thus, engineers are developing IoT sensors that operate on renewable energy sources such as solar or kinetic energy. This is particularly important where sensors are located in remote or inaccessible locations.  The use of energy harvesting is in turn prompting sensor manufacturers to reduce the sensor’s form factor to reduce energy consumption, and improve the signal-to-noise ratio to filter out noise and interference that could also sap the sensor of needed power.

Because hazardous or remote locations make installation of physical sensors difficult, some IoT installations now use soft or virtual sensors. Soft sensors are computational algorithms that estimate the value of a difficult-to-measure quantity, based on other existing physical sensors and algorithms/computational models that infer the value of the measured quantity. A typical soft sensor creates a predictive model that uses real-time data from instrument and laboratory analyses to estimate process and production conditions. These models act as inferential sensors to predict quality parameters, possibly as an alternative to additional physical sensors. 

A virtual sensor is similar to a soft sensor, but bases its values purely on algorithms and computational models.

Sensor fusion, which involves merging data from several sensor inputs, will continue to become more crucial, particularly in autonomous driving. In those applications, sensor data is coming from LiDAR, radar, and 3D cameras. As these sensor inputs sense different features of the driving environment, it is necessary to take and interpret the data from these sensors to get a more accurate analysis of the driving situation. Implemented correctly, sensor fusion enables the vehicle to take an appropriate course of action that is efficient, reliable, and above all, safe.

Biosensor and disposable sensor technology have matured in recent years and have been adopted in the healthcare industry. Also known as a “biological sensor,” a bio sensor has a bio element interacts with the tested analyte, and a transducer that  converts the biological response into an electrical signal. Depending on their application, biosensors are also known as immunosensors, optrodes, resonant mirrors, chemical canaries, biochips, glucometers, or biocomputers.

Spencer Chin is a Senior Editor for Design News covering the electronics beat. He has many years of experience covering developments in components, semiconductors, subsystems, power, and other facets of electronics from both a business/supply-chain and technology perspective. He can be reached at [email protected].