Smart Sensor vs Base Sensor - What's the Difference? | Symmetry Blog
About Tyler Wojciechowicz
With the introduction of new Internet of Things technology comes the need for newer innovations in sensor technology. One of the most impactful advancements in sensor technology is the advent of the “smart sensor.”
Continue reading to find out more about the smart sensor and how it differs from traditional “base” sensors.
What is a smart sensor?
A smart sensor is a sensor that contain an embedded Digital Motion Processor (DMP). The advantage of this is that it can take input from the physical environment and uses built-in compute resources to perform predefined functions upon detection of specific input and then process data before passing it on. As you may already guess, processing of the data captured by the sensor is done on the sensor’s IC with the embedded DMP. The processed data is then shared to the rest of the device through a serial interface.
At a minimum, a smart sensor is made of a sensor, a microprocessor and communication technology of some kind. Computation resources are provided by the low-power mobile microprocessor. The compute resources must be an integral part of the physical design -- a sensor that just sends its data along for remote processing is not considered a smart sensor.
A smart sensor may also include a number of other components besides the primary sensor. These components can include transducers, amplifiers, excitation control, analog filters and compensation. A smart sensor also incorporates software-defined elements that provide functions such as data conversion, digital processing and communication to external devices.
For example, the ICM-20648 from InvenSense is their flagship "smart sensor" meaning is DOES have an embedded DMP.
https://www.symmetryelectronics.com/products/invensense/icm-20648/
What about “non-smart” base sensors?
A base sensor is a sensor that does not include an embedded Digital Motion Processor, or DMP. This typically contains just the sensor itself, while all processing and calculation work is done by the manufacturer. By using a base sensor, a manufacturer takes advantage of a lower price point with the component and enables full control of the design process.
For example, the ICM-20602 from InvenSense is their flagship "base sensor" meaning it does NOT have an embedded DMP.
https://www.symmetryelectronics.com/products/invensense/icm-20602/
Why use a smart sensor?
Saves space - Because smart sensors are built with an embedded DMP, calculations are done on the sensor, saving space usually reserved for routing from sensor to MCU for processing.
Saves power - Because the embedded DMP computes the sensor input into usable data, the device’s MCU does not have to expend energy to process sensor data, saving power that would normally be reserved for base sensors.
By using a smart sensor, a manufacturer speeds up the design cycle, avoids errors that may occur during routing between a traditional sensor and MCU, and saves design costs, while also receiving a highly efficient product that is harder to achieve on a base sensor.
Smart sensors enable more accurate and automated collection of environmental data with less erroneous noise amongst the accurately recorded information. These devices are used for monitoring and control mechanisms in a wide variety of environments including smart grids, battlefield reconnaissance, exploration and a great number of science applications.
The smart sensor is also a crucial and integral element in the Internet of Things (IoT), the increasingly prevalent environment in which almost anything imaginable can be outfitted with a unique identifier (UID) and the ability to transmit data over the Internet or a similar network. One implementation of smart sensors is as components of a wireless sensor and actuator network (WSAN) whose nodes can number in the thousands, each of which is connected with one or more other sensors and sensor hubs as well as individual actuators.
Why use a base sensor?
With the release of smart sensors in the market, base sensors may seem obsolete in IoT. However, some manufacturers may opt to use base sensors in their designs if they plan on developing highly specified products, where complete control of the design is necessary. Additionally, in cases where the application being built will be sold in mass quantities world-wide, using a base sensor over a smart sensor may save component costs, although the quantity must be high enough to offset the costs of custom design, implementation, testing while finding a set up that can match the efficiency of a smart sensor. For most applications, this will not be the case, and a smart sensor will usually offer a better solution at lower overall cost.
Which one should you use?
Whether you choose a base sensor or a smart sensor depends on your design needs.
Customers that want to do their own calculations on a host MCU would use a "base sensor" e.g. Amazon Alexa. Customers that would like all these calculations done on the IC (with the DMP) and results spit out via serial interface would use a "smart sensor" e.g. Startups/ companies without a lot of design resources.
If you have questions about your specific application, Symmetry’s Application Engineers are available to help you find the perfect sensor for your needs.
InvenSense offers smart sensors and base sensors for all your sensing needs.
Symmetry Electronics stocks InvenSense products to help your IoT applications capture environmental data of all kinds. InvenSense offers both smart sensors and base sensors in a variety of different axis configurations.