Tag Archives: sensors

Sensing Temperature with NTC Thermistors

Temperature sensors using NTC thermistors are built from sintered semiconducting ceramic material. Such materials contain a mixture comprising several metal oxides. The specialty of these materials is they possess charge particles, which allow current to flow through the thermistor, and display large changes in its resistance value even when the change in temperature is rather small. The manufacturing process allows standard NTC thermistors to operate effectively in the temperature range between Read more [...]

How to Select Current Sensors?

To select an appropriate AC current sensor for an application, you must know the operational frequency range and the current rating the sensor will encounter. Additional considerations that you will need to decide are the type of the sensor, its mounting (through-hole or surface mount), turns ratio, and the overall dimensions. Sensor type refers to a sensor only configuration, where a conductor integral to the application forms the primary. Another type could be a complete current transformer where Read more [...]

Inertial Sensing for Automation

In any type of industry, whether it is automotive, unmanned aerial vehicles, energy, logistics, agriculture, or manufacturing, automation brings increasing promises of great gains in terms of efficient utilization of resources, achieving accuracy, and safety. To achieve these gains it is necessary to identify the appropriate sensing technologies that will enhance the contextual knowledge of the equipment’s condition. As the location or position of an equipment is a valuable input, precision inertial Read more [...]

Specifying Fiber Optic Sensors

The industry prefers fiber optic sensors as they work well in tight spots and in applications that have a high degree of electrical noise. Fiber optic sensors are useful in machines, fixtures, and conveyors for sensing part presence as an important component of industrial automation. The industry often requires controlling sequence and error-proofing assembly based on the presence or absence of a part. In many cases, it is simply impossible to know whether a part is where it should be or the holder Read more [...]

GrovePi Kits for the Raspberry Pi

If you are looking to interface sensors to the Raspberry Pi (RBPi), the popular single board computer, GrovePi+ from Dexter Industries (SEED Studios) makes it very easy with their starter kit. The kit carries a GrovePi+ board, including more than 10 carefully selected sensors along with the necessary interfacing cables. The kit is very easy to use, as the user only has to plug the GrovePi+ board over your RBPi, and connect the necessary sensor to the board. GrovePi provides a powerful platform for Read more [...]

Using Reed Switches as Sensors

Any ordinary electrical switch has two contacts. Push-type switches are spring loaded so that pushing a button brings them together and they spring apart on releasing the button. Rocker switches have mechanical levers that close the contacts when in one position, while in the other position they pull apart. In reed switches, the two contacts are in the shape of metal reeds, each coated with a metal that does not wear easily. The reeds are made from a ferromagnetic material, so they are easy to magnetize. Read more [...]

A Rain Alert for the Raspberry Pi

This Raspberry Pi (RBPi) rain alert will let you know when it starts to rain, so you can reel in the clothes you had let out to dry after washing. Although the kit uses an RBPi3, any model of the RBPi family can easily handle this project. A later extension can make it send tweets as well, but for now, it simply triggers a buzzer. The primary sensor in this project senses falling raindrops. This raindrop sensor is actually a printed circuit board with two traces running across the entire board in Read more [...]

Motion Tracking through the MC3672

This year, the MSEC or MEMS & Sensors Executive Congress had mCube exhibiting their incredibly small and low-power MC3672, an inertial sensor product. This is a three-axis accelerometer, and its size is only 1.1 x 1.3 mm. This tiny WLCSP packaged device is a low parasitic unit, with enormous possibilities of unobtrusive use as low power motion tracking in wearable design, and in a completely new set of applications in future. Recently, mCube acquired Xsens and they were able to couple a sensor Read more [...]

Using Hall-Effect Type Sensors Effectively

We are familiar with appliances such as wine coolers, freezers, and refrigerators. They keep out beverages and food cold, extending their useful life. Most often, these appliances have lights that illuminate the insides when the user opens their doors. Since the lights only need to be on when the user opens the door, usually, the designer of such appliances place a sensor to detect the opening and closing of the door. A sensor of the Hall-effect type can detect the position of the door. In refrigerators, Read more [...]

Sensing Movement in Three Axes

All modern vehicles must sense the position and movement of automotive control functions such as turn signal indicators and gear selectors. However, engineers face challenges here with conventional sensor technologies as the requirement is for sensing movement in the three axes simultaneously. The challenge lies in the physical size of the device, its reliability, power consumption, and its cost. However, 3-D magnetic sensing technology, recently introduced, could be helping engineers to address Read more [...]