If you were not previously aware of the Great Pacific Garbage Patch (GPGP), viewing “Under Paris,” when it streamed on Netflix in the summer of 2024, provided painful awareness of a serious and growing problem — even though the movie was fantasy. “Under Paris” garnered over 69.6 million views in its premiere in June, making […]
Frequently Asked Question (FAQ)
How do fingerprint, finger geometry & vein recognition biometrics work?
Unique traits of fingers and hands are commonly used biometric markers. Those traits include fingerprints, finger vein recognition, hand recognition, and finger geometry. Hybrid identification systems have been developed that combine fingerprints and finger vein recognition. Artificial intelligence (AI) has recently been applied to fingerprint analysis, and it promises to increase its utility. Fingerprint and […]
How do body odor recognition biometrics work?
A body odor recognition system uses an electronic nose (E-nose) with numerous chemical sensors to detect and identify volatile organic compounds (VOCs) in the air. General-purpose E-noses are available to detect and identify complex chemical mixtures that constitute aromas, odors, fragrances, and formulations. Breathalyzers are specialized E-noses used to measure the amount of alcohol in […]
What sensors indicate the weather: part 2
With extreme weather conditions, people directly impacted by the pending situation need to know how severe it will be. For hurricanes, the Saffir-Simpson Hurricane Wind Scale provides a rating from 1 (very dangerous winds that will produce some damage) to 5 (catastrophic damage will occur) based on a hurricane’s maximum sustained wind speed. This approach […]
What are the seven characteristics of biometrics that make it useful for security?
A biometric trait must be reliable to be a useful security tool. This article begins with an overview of the seven characteristics used to compare the reliability of biometric traits. It then looks at how well some common biometric traits satisfy those requirements. It considers how multimodal authentication and sensor fusion can enhance security and […]
What sensors indicate the weather: part 1
Temperature, barometric pressure, humidity, wind speed and direction, and possible rainfall (or snowfall) in specific areas are common indicators of current and future weather conditions. However, other sensor inputs, such as pressure drop, air quality, particulate matter (including dust), and more (storm surge), are frequently required to identify and react to extreme weather conditions. The recent hurricanes […]
What determines the connectivity bandwidth needed in a machine vision system?
This article reviews resolution, definition, frame rate, and bit depth and how they impact connectivity bandwidth requirements. It then looks at a practical example of the requirements for an effective automotive pedestrian imaging system, including the importance of the Johnson criteria for night vision. Pixels, their sizes, numbers, and composition are the bedrock upon which […]
Does TPMS need a pressure sensor?
It seems obvious that a Tire Pressure Monitoring System (TPMS), required by several governments, would need a pressure sensor. But that’s not true. Alternative approaches take advantage of other sensing capabilities in a vehicle, computing, and algorithms to implement a solution for TPMS that meets legislated requirements. The alternative, indirect, approach has been used for […]
What are magnetic rotary encoders?
Part 1 of this FAQ looked at the optical rotary encoder, a low-cost, high-resolution, easy-to-use sensor for indicating incremental shaft position (although it can be “upgraded” to indicate absolute position as well). Q: What is the basic principle of the magnetic encoder? A: The magnetic encoder uses a rotating gear made of ferrous metal, and […]
What are optical rotary encoders?
Accurate measurement of rotary shaft motion, including position, velocity, and acceleration, is crucial in numerous applications. This is typically achieved by incorporating a rotary encoder into the motor or shaft assembly. While “rotary encoder” is often abbreviated to “encoder,” it should not be confused with other electromechanical or electronic encoding devices used for data format […]
