Shawyer describes a new EMdrive thruster design that has a single flat superconducting plate on one end, with a uniquely shaped, non-conducting plate on the other.
This is necessary to minimiZe the internal Doppler shift – a change in frequency or wavelength of a wave for an observer moving relative to its source – and also keep manufacturing costs down.
* It enables the drive to be easily manufactured
* It will make a viable superconducting thruster easier. Shawyer believes a superconducting thruster will produce a lot of thrust
Shawyer is working with an unnamed UK aerospace company to develop his second generation EM Drive, which he says will produce thrust many orders of magnitude greater than that observed by NASA’s Eagleworks team or any other laboratory.
Shawyer’s first generation EmDrive device was claiming to produced 200 milliNewtons (20grams) of force.
The most amount thrust that has ever been claimed from EMDrive tests was by Chinese scientists in 2012. They claimed to produce 720 milliNewtons (72g) of thrust in a system built. Researchers working under Juan Yang at the Northwestern Polytechnical University (NWPU) in Xi’an developed their own prototype resonant cavity thruster in 2008, publishing a report in their university’s journal on the theory behind such devices. In 2012-2014 they reported measuring net thrust in a series of preliminary tests, however in 2014 they found that this had been an experimental error introduced by a power cable. In a revised study with an improved model, they found that any actual thrust was too small for their setup to measure (less than 1mN for a 230W power source)
Shawyer claims a race is on and the second-generation EmDrive is being developed by several players privately including himself, and the new version of the device would be able to achieve tonnes of thrust (1T = 1,000kg) rather than just a few grams.
A radio frequency (RF) resonant cavity thruster is a proposed type of electromagnetic thruster in which electromagnetic radiation is confined to a microwave cavity, and provides thrust to the cavity in a particular direction as the radiation reflects within the cavity.
Such a thruster would be a type of reactionless drive, providing thrust from electricity without consuming a propellant.
Peer Reviewed Paper from NASA Eagleworks in December
In early 2015, Paul March from Eagleworks made new results public, claiming positive experimental force measurements with a torsional pendulum in a hard vacuum: about 50 µN with 50 W of input power at 5.0×10−6 torr and new null-thrust tests. The new RF power amplifiers were said to be made for hard vacuum, but still fail rapidly due to internal corona discharges. With not enough funding to replace or upgrade them, measurements are still scarce and need improvement before a new report can be published.
Glenn Research Center offered to replicate the experiment in a hard vacuum if Eagleworks manages to reach 100 µN of thrust, because the GRC thrust stand cannot measure forces lower than 50 µN.
Eagleworks later announced a plan to upgrade their equipment to higher power levels, use vacuum-capable RF amplifiers with power ranges of up to 125 W and to design a new tapered cavity analytically determined to be in the 0.1 N/kW range. The test article will be subjected to independent verification and validation at Glenn Research Center, the Jet Propulsion Laboratory and the Johns Hopkins University Applied Physics Laboratory.[
Theseus is going to be launching a demo cubesat which will use Cannae thruster technology to maintain an orbit below a 150 mile altitude. This cubesat will maintain its extreme LEO altitude for a minimum duration of 6 months. The primary mission objective is to demonstrate our thruster technology on orbit. Secondary objectives for this mission include orbital altitude and inclination changes performed by the Cannae-thruster technology.
Cannae’s thruster technology is capable of generating thrust from a few uN up through several newton thrust levels and higher levels. The Cannae thruster technology is particularly useful for small satellite missions due to low power, mass and volume requirements. Our thruster configuration for the cubesat mission with Theseus is anticipated to require less than 1.5 U volume and will use less than 10 watts of power to perform station keeping thrusting.
Once demonstrated on orbit, Theseus will offer our thruster platforms to the satellite marketplace
SOURCES- UK Patent Office, IB Times UK, Emdrive sute, Cannae site, Wikipedia