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Aug 5, 2019

Polyphase reaction synchronous motors

Posted by in category: sustainability

THE reaction synchronous motor in its present form (salient-pole rotor without field coils) is one of the oldest types of electric motors, antedating the i.

Aug 5, 2019

Application filed by Klaus L Hansen

Posted by in category: futurism

Dec. 23, 1952 K. L. HANSEN 2,623,201

SYNCHRONOUS MOTOR Filed Aug. 5, 1950 s Sheets-Sheet 1 1 A0/d577i645 l i A? AZ v fl/Z INVEN TOR. M 13 Z. 351151 1? 2 m WWW; filth/way Dec. 23, 1952 K. L. HANSEN 2,623,201.

Aug 5, 2019

Polyphase system

Posted by in category: energy

A polyphase system is a means of distributing alternating-current electrical power where the power transfer is constant during each electrical cycle. Polyphase systems have three or more energized electrical conductors carrying alternating currents with a defined phase angle between the voltage waves in each conductor; for three-phase voltage, the phase angle is 120° or ~2.09 radians. Polyphase systems are particularly useful for transmitting power to electric motors which rely on alternating current to rotate. The most common example is the three-phase power system used for industrial applications and for power transmission. Compared to a single-phase, two-wire system, a three-phase three-wire system transmits three times as much power for the same conductor size and voltage.

Systems with more than three phases are often used for rectifier and power conversion systems, and have been studied for power transmission.

Aug 5, 2019

Tesla Polyphase Induction Motors

Posted by in category: futurism

Most AC motors are induction motors. Induction motors are favored due to their ruggedness and simplicity. In fact, 90% of industrial motors are induction motors.

Nikola Tesla conceived the basic principles of the polyphase induction motor in 1883 and had a half horsepower (400 watts) model by 1888. Tesla sold the manufacturing rights to George Westinghouse for $65,000.

Most large ( 1 hp or 1 kW) industrial motors are polyphase induction motors. By polyphase, we mean that the stator contains multiple distinct windings per motor pole, driven by corresponding time-shifted sine waves. In practice, this is two or three phases. Large industrial motors are 3-phase. While we include numerous illustrations of two-phase motors for simplicity, we must emphasize that nearly all polyphase motors are three-phase. By induction motor, we mean that the stator windings induce a current flow in the rotor conductors, like a transformer, unlike a brushed DC commutator motor.

Aug 5, 2019

Could Rat Brains Hold the Secret to Robots with Better Navigational Skills?

Posted by in category: robotics/AI

BU researchers have discovered specialized brain cells that provide rats—and most likely, humans— with personalized maps of their surroundings, helping them navigate through obstacles. The findings could lead to improved autonomous vehicles that can navigate unpredictable and dynamic terrain.

Aug 5, 2019

SpaceX’s Florida Starship hits growth spurt as Texas Starship begins bulkhead installation

Posted by in categories: Elon Musk, space travel

In the last week alone, SpaceX’s twin orbital Starship prototypes have made some truly jaw-dropping progress. Onlookers have witnessed Florida’s Starship push through a rapid growth spurt, while the company’s Texas team has begun to install propellant tank bulkheads and work on a triple-Raptor thrust structure.

Meanwhile, SpaceX CEO Elon Musk has suggested that one or both of the orbital-class Starship prototypes could be “almost ready to fly” by August 24th, the date of the CEO’s next official update on Starship (formerly BFR and ITS). Although the actual challenge of building a massive, orbital-class launch vehicle is far subtler than the visible steelwork needed to build its primary structure and pressure vessels, the veritable leaps forward made in both Texas and Florida in the last 7–10 days are extremely encouraging signs.

Starting off in Boca Chica, Texas, SpaceX’s team of engineers and technicians have been simultaneously handling Starhopper’s first untethered flight test (completed on July 25th) and building the facility’s orbital-class Starship prototype. Most significantly, after a few days of preparation, what is likely the Texas Starship’s first bulkhead was lowered inside its ~25m-tall (80 ft) barrel section, composed of the spacecraft’s propulsion section and propellant tanks.

Aug 5, 2019

Robotics team from the Flathead wins regional competition

Posted by in category: robotics/AI

KALISPELL, Mont. — Two middle schoolers in the Flathead are making a name for themselves in the robotics world. Katie Eberhardy and Jessie Chadwick recently won the regional, NASA-sponsored Apollo Next Great Leap Student Challenge.

Eberhardy and Chadwick’s team—the Lunar Loonies—was the only all-girl team in the competition, and one of the smallest of the about 20 other teams.

“Some teams had six to eight people,” Chadwick said. “We’re just a team of two.”

Aug 5, 2019

3D bioprinting breakthrough leads to full-scale, functioning heart parts

Posted by in categories: 3D printing, bioprinting, biotech/medical

While in its early stages, bioprinting of human tissue is an emerging technology that is opening up some exciting possibilities, including the potential to one day 3D print entire human organs. This scientific objective has now grown a little bit closer, with researchers at Carnegie Mellon University reporting a breakthrough that enabled the printing of full-scale heart components that in some cases functioned similarly to the real thing.

Aug 5, 2019

Humans will be immortal in just 20 years when ‘only religious people will die’

Posted by in category: life extension

When actual immortality is available, will anybody continue to pay religion for unprovable, highly doubtful supernatural immortality?


HUMANS will have the option to stay young forever in just a few decades, according to a leading…

Aug 5, 2019

France Is Making Space-Based Anti-Satellite Laser Weapons

Posted by in categories: economics, military, satellites

France will develop satellites armed with laser weapons, and will use the weapons against enemy satellites that threaten the country’s space forces. The announcement is just part of a gradual shift in acceptance of space-based weaponry as countries reliant on space for military operations in the air, on land, and at sea—as well as for economic purposes, bow to reality and accept space as a future battleground.