The high-speed all-electric railroad locomotive uses a catenary-wire system and pantograph power-transfer arrangement, which appears to violate good engineering practice and should not work. Still, it does, transferring hundreds of amps via a contact point moving at over 100 miles/hour.: There are four ways to power a railroad locomotive: via a steam engine (with a […]
The proving ring – An alternative to dead-weight calibration, Part 2
The proving ring implements a simple principle of physics to provide precise and tangible indication of applied weight ranging up to hundreds of thousands of pounds Part 1 of this article looked at the basic problem of calibrating sensor-based data acquisition and especially the problem of calibration of weight and force. This part looks at […]
LiDAR and Time of Flight, Part 4: Circuitry and advances
LIDAR systems and ToF techniques are critical to providing self-driving cars with a detailed picture of the surrounding and is used in many research applications as well. This is the final part of a four-part series on LIDAR systems and ToF techniques. The high-level block diagram of a LIDAR system inherently glosses over the many […]
LiDAR and Time of Flight, Part 3: Emitters, sensors, and scanners
LIDAR systems and ToF techniques are critical to providing self-driving cars with a detailed picture of the surrounding and is used in many research applications as well. This is part three of a four-part series on LIDAR systems and ToF techniques. At the front end of a LIDAR system is the photon emitter and its […]
LiDAR and Time of Flight, Part 2: Operation
LIDAR systems and ToF techniques are critical to providing self-driving cars with a detailed picture of the surrounding and is used in many research applications as well. This is part two of a four-part series on LIDAR systems and ToF techniques. Just as for radar and sonar, the LIDAR concept is simple but the execution […]
LiDAR and Time of Flight, Part 1: Introduction
LIDAR systems and ToF techniques are critical to providing self-driving cars with a detailed picture of the surrounding and is used in many research applications as well. Many of the major automobile vendors, along with well-known non-auto companies such as Google, are devoting major resources to developing autonomous vehicles (often called “self-driving cars”). These vehicles […]
RCA & Color TV: A dominant company and standard, both now gone – Part 2
Part 1 of this article provided context for the critical role of David Sarnoff, development of color TV, and RCA’s place in modern electronics; this part looks at the solution to the compatible color-TV challenge and the eventual corporate decline. Problems met and solved The first apparently intractable issue RCA had to solve was what […]
RCA & Color TV: A dominant company and standard, both now gone – Part 1
Analog color TV is now obsolete, but the story of its development shows both the power and fragility of market dominance. The ubiquitous presence and dominant positions of Facebook, Amazon, Apple, and Google in our lives – for good and bad – make it logical to think that these companies will be around “forever” and […]
Vacuum tubes we still (have to) use: The photomultiplier tube, Part 2
We live in a world of solid-state active devices that have made most vacuum tubes obsolete, but a few types remain as they are still indispensable. Part 1 of this article explained the basics of the photomultiplier tube. This part looks into other PMT characteristics. Q: Are there solid-state functional equivalents to the PMT? A: […]
Vacuum tubes we still (have to) use: The photomultiplier tube, Part 1
Maybe we can’t live with them, but we can’t live without them, at least not yet: the photomultiplier tube and the traveling wave tube are two vacuum electron-tube devices that are still viable and needed in our solid-state world.) It’s widely accepted conventional wisdom that almost “everything” has gone solid state and that vacuum tubes […]