Haptics capabilities are embedded in smartphones and game controllers, and their use is expanding into robotic controls, automobile consoles, and more; the physical actuator and its driver are the key hardware elements. Haptics-enhanced devices are all around us, even if we don’t consciously realize it. The smartphone with different vibrations depending on who is calling […]
FAQ
Basics of amplitude distortion
Amplitude distortion is the unintended modification of a signal, typically while undergoing amplification. Amplitude modulation, in contrast, is the intended modification of a carrier wave in response to a varying audio, video or other information-bearing signal. Sources of amplitude distortion include noise and interference, but the main source is non-linear amplification. Amplitude distortion can include […]
The Fresnel lens: An obsolete innovation finds a 21st-century role – Part 4
Part 3 looked at how Fresnel enhanced to the performance of his lens in the lighthouse application; this part looks at how the lens itself has been extended by new materials and manufacturing techniques and found modern applications even though lighthouses are obsolete. Fresnel’s legacy lives on, in unrelated ways There no argument: lighthouses are […]
The Fresnel lens: An obsolete innovation finds a 21st-century role – Part 3
Part 2 looked at the background to Fresnel along with the principle and implementation of his innovative lens. This part extends that investigation by looking at closely related innovations which he developed to maximize the system performance. Improving it further The lens was only part of his solution since the optics needs a near-ideal “point […]
AI-assisted screening for COVID-19 using CT images
Although COVID-19 tests are one means to determine infection, the rapid spread of the disease has created a shortage of test kits and a tight supply of reagents that are used to create test kits. Symptoms are another indication, but some of the infected show very mild or no symptoms. Another method leading to a […]
The Fresnel lens: An obsolete innovation finds a 21st-century role – Part 2
Part 1 examined a major technical problem of the 19th century: improving the efficiency and reach of the lighthouse beam, and why simply going “bigger” would not be possible. A new way of seeing the problem New ideas were needed, and the French government in the early 1800s was aware of the problem, even linking […]
The Fresnel lens: An obsolete innovation finds a 21st-century role – Part 1
Lighthouses may seem like quaint artifacts of a bygone era and now mostly used as tourist attractions, but as marine-based commerce expanded in the 18th and 19th centuries, they were indispensable for ship navigation and guidance to an extent we probably can’t imagine (this was before the gyrocompass, radar, and GPS world, of course). As […]
Overview of electrical measuring instruments, part three
In recent columns, we’ve given a quick review of some basic instrumentation common to most engineering work benches. Here are a few more instruments found in many engineering labs. Signal generator Signal Generator is a generic term describing various instruments, all sharing a single rationale, which is that a device under test (DUT) requires a […]
Comparing magnetic cores for power inductors
It is helpful to know how the material properties and geometries of magnetic cores affect the ability of inductors to store energy or filter current. There can be a mystique surrounding the specs of magnetic cores used in power inductors, due partly to the fact that magnetic materials may not be well characterized for handling […]
Breaking BLE – Vulnerabilities in pairing protocols leave Bluetooth devices open for attack
Despite built-in safe-guards, Bluetooth Low Energy IoT devices are vulnerable to hacks when they communicate over the air. Here are the basics of the problem. Leland Teschler, Executive Editor If you eyeball internet-of-things items ranging from smart ac plugs to motion sensors you typically find connectivity via the Bluetooth Low Energy (BLE) standard. A lot […]