This alternative to time-of-flight LiDAR has unique complexities and distinct attributes. Modeling and simulation Q: What design analysis is done on an FMCW LiDAR system? A: In a word: lots. Much of the analysis parallels or leverages what has been done for radar, as there are so many similarities in operating principles and the analytical […]
FAQ on the basics of FMCW LiDAR: part 2
This alternative to time-of-flight LiDAR has unique complexities and distinct attributes. Part one begins our look at what FMCW LiDAR is, the architecture and components it uses, and its performance capabilities. Electronic and optical components build a system Q: What hardware components are needed to create a basic FMCW LiDAR system? A: One perspective is […]
FAQ on the basics of FMCW LiDAR: part 1
This alternative to time-of-flight LiDAR has unique complexities and distinct attributes. When engineers hear the phrase LiDAR, an acronym for Light Detection and Ranging, they generally think of time-of-flight (ToF) systems. ToF LiDAR is widely used in automotive and robotic applications to “see” surroundings and obstacles. But there is another, radically different LiDAR approach: frequency […]
Understanding and interfacing with RTDs: part 2
This part transitions from RTD principles to ICs available for interfacing. ICs simplify the RTD interface As with their other resistor-based temperature-sensing components, the RTD looks simple to use. After all, it is a two-terminal resistor with no parasitics of consequence in the relatively slow-moving world of temperature sensing. Nonetheless, as with thermistors and many […]
Understanding and interfacing with RTDs: part 1
This versatile temperature sensor is one of many viable alternatives. Temperature is the most widely sensed real-world parameter, and knowing the temperature with some combination of accuracy, precision, and repeatability is critical in many applications. A widely used choice for the temperature sensor is the resistance temperature detector (RTD), a precision metal element usually made […]
Ultrasonic sensing part 2: dynamic fluid flow
This second part looks at measuring fluid flow rates instead of object presence. Find part one here. Sensing fluid flow Beyond basic object detection, ultrasonic transducers are used for non-invasive, non-contact measurement of liquid and gas flow rates (velocity). For these applications, the transducers operate at higher frequencies, typically above 200 kHz, to provide the […]
Ultrasonic sensing part 1: static presence
Ultrasonic energy is widely used to sense the presence of nearby objects and even determine their distance if needed, as well as to measure fluid flow rates in industrial and scientific applications. The advantages of ultrasound are that it is relatively easy to apply, is accurate, has very minimal safety or risk factors, carries no […]
FAQ on optical proximity sensing: part 2
A light source and photosensor combine for effective, reliable, non-contact proximity detection of nearby objects. Part 1 of this article looked at the principles and three basic approaches to optical proximity sensing, also called photoelectric sensing. This part looks at physical implementations of the system, input/output specifics, and other considerations. Q: Is this a relatively […]
FAQ on optical proximity sensing: part 1
A light source and photosensor combine for effective, reliable, non-contact proximity detection of nearby objects. Non-contact proximity sensors detect the presence or absence of nearby objects (including animals and people) using basic physics phenomena such as capacitive and inductive electromagnetic fields, light, or sound. Many techniques are used for this sensing, each offering different operational […]
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 […]
