Static objects are quickly becoming a thing of the past. Connected devices are now a way of life: wearable technology that detects an oncoming seizure, street lamps that measure traffic patterns to improve energy efficiency and homes that creates the perfect environment of temperature, lighting, music, etc. before the owner arrives home. Common objects are now required to sense, capture and communicate data. IDC estimates that by 2020 there will be 30 billion internet-connected, sensor-enabled objects and another 182 billion that could easily be enabled. When the term “Internet of Things” was coined a few years ago, it seems like a rather abstract, “out there” kind of notion. Now it is our everyday reality. As “things” become increasingly connected to the Internet, other objects and even people, there is an essential electronic component driving all of these new technologies: sensors. If the microprocessor is the brain of the device, then the sensor is the spinal cord.
Whether you’re creating a highly responsive device or simply want to optimize energy efficiency in your product, sensors increasingly drive the design of the board. Beyond pure function, there are a number of things to consider when selecting the right sensor for your long-term needs. And, selecting the right sensor early in the design process will not only impact your overall design, but will help make sure you are meeting your long-term strategy and supply chain goals.
It’s probably obvious, but the first consideration when selecting a sensor is the basic function you need the device to perform. Typically, sensors have three primary functions: monitoring, feedback and control, and adding intelligence. Next, decide if any “bonus” functionality could add value or extend the life of your product. Increasingly, devices are designed with multiple sensors offering a full range of functionality. Temperature and humidity combination sensors will have a more precise output compared to each sensor on its own. Power consumption is often a consideration in creating longer product lifecycles, so sensors that create a way to measure and increase energy efficiencies are increasingly being built into devices of all sorts. Sensor fusion is also a growing trend – these multifunction sensors improve accuracy, save cost and consume less power than traditional discrete sensors.
FIT and FORM
Does your sensor need to be a specific size and weight for your application? Space limitations will dictate both the size and shape of sensor you need. Packaging of the sensors should be considered early in the design process. Sensor size and packaging is often determined by the environment of the sensor. If the conditions are highly humid or high temperature, a stainless steel housing may be required to protect the inside of the sensor. Likewise, if the device needs to be cleaned, washed down or is likely to be exposed to elements such as rain, a stainless steel package is also needed. Other special considerations include the need for the sensor to withstand strong winds or physical impact. Sometimes the desired accuracy or sensing range may affect the overall size since most longer-range sensors also have a larger footprint. If size is a concern, there are many "combination" sensors on the market that will reduce the size of the component as well.
The degree to which a device needs to deliver accurate results varies widely. In many medical devices, accuracy is likely a mission-critical consideration. The more flexible you are in the level of accuracy you need, the more likely you are to find multiple sensors that meet your requirements. The more accuracy required and the more specific your requirements are, the fewer options you will have in sensor technology. Typically, sensors providing the most basic functions can deliver a high degree of accuracy for a reasonable cost.
Prices can range widely in a fragmented sensor market. MEMS components have become highly commoditized due to the rise of IoT. For many sensors applications, no duplicate form, fit or function exists. So, choosing the right sensor at the very beginning of your design is even more critical. If the intention is to create a price-competitive or price-conscious product, you’ll need to carefully consider the degree of accuracy and specific functionality you really need in your sensor technology. If you select a high-functioning and accurate sensor for your prototype, but then are challenged with finding a more economical solution, typically it means going back to the literal drawing board.
Fortunately, most sensor manufacturers offer evaluation boards, which allow for quick and impressive demos of the sensor technology. These tools make it easy to test hardware and create prototypes. The demos are produced on boards so you can simply plug them into your application. These boards are modular and can often times be used with many open-source hardware platforms. This is an easy and cost-effective way to determine which sensors are best for your product.
DISTRIBUTION RESOURCES ADD LONG-TERM VALUE
Distributors such as TTI are an excellent resource to tap into at the beginning of a design project. With access to all major manufacturers and deep knowledge in the spectrum of available sensors, distributors can help you find the right solution, faster. TTI also offers many supply chain tools and resources that help OEMs optimize their supply chain throughout the product’s lifecycle.