ESA's Space Situational Awareness (SSA): Bug Eyed Telescope

The SSA-NEO system is based on syndicating and federating observation and tracking data provided by a large number of European and international sources. 

Credit: ESA - P.Carril

Spotting Earth-threatening asteroids is tough partly because the sky is so big but insects offer an answer, since they figured out long ago how to look in many directions at once.

As part of the global effort to hunt out risky celestial objects such as asteroids and comets, ESA is developing an automated telescope for nightly sky surveys.

This telescope is the first in a future network that would completely scan the sky and automatically identify possible new near-Earth objects, or NEOs, for follow up and later checking by human researchers.

But a web of traditional telescopes would be complex and expensive because of the number required.

Adding to the problem, the system must be able to discover objects many times fainter than the naked eye can perceive.

While no network can spot all potentially hazardous objects, under favourable conditions it should detect everything down to about 40 m in diameter at least three weeks before impact.

The answer is a new, European telescope nicknamed 'fly-eye' that splits the image into 16 smaller subimages to expand the field of view, similar to the technique exploited by a fly's compound eye.

The design is modular, and allows for mass and cheaper production and lower maintenance costs. It will be used to build the prototype, to be fielded by ESA's Space Situational Awareness (SSA) programme early next year.

"This novel technology is key to the future NEO survey network," says Gian Maria Pinna of the SSA office.

A new, European telescope nicknamed ‘fly-eye’ splits the image into 16 smaller subimages to expand the field of view, similar to the technique exploited by a fly’s compound eye. 

Such fly-eyed survey telescopes provide a very large field of view: 6.7° x 6.7° or about 45 square degrees. 6.7° is about 13 times the diameter of the Moon as seen from the Earth (roughly 0.5 degrees). 

Credit: ESA/Compagnia Generale dello Spazio CGS

Performance equivalent to large telescope

These fly-eyed survey telescopes offer performance equivalent to a 1 m-diameter telescope, and provide a very large field of view: 6.7° x 6.7° or about 45 square degrees; 6.7° is about 13 times the diameter of the Moon as seen from the Earth.

"The new telescopes would provide the resolution necessary to determine the orbits of any detected objects," says Gian Maria.

"If the prototype confirms the expected performance, it will pave the way to full procurement and deployment of the operational network of telescopes."


Future telescope in operation. Credit: Compagnia Generale dello Spazio – CGS

This summer, ESA signed a contract for about €1 million with a consortium led by CGS S.p.A (Italy), comprising Creotech Instruments S.A. (Poland), SC EnviroScopY SRL (Romania) and Pro Optica S.A. (Romania) for the detailed design of the advanced telescope.

It is expected that the detailed design will be followed by several additional contracts with European companies valued at up to €10 million for building and deploying the first survey prototype telescope.

"The development of the first optical sensor specific to ESA's NEO search and discovery activities is a fundamental step toward Europe's contribution to safeguarding our planet from possible collisions by dangerous objects," notes Nicolas Bobrinsky, Head of the SSA Programme.

DelFly Explorer: Dutch scientists flap to the future with 'insect' drone - Video

A view of the DelFly Explorer, the world's lightest autonomous flapping drone, during a demonstration at the Delft Technical University, on January 29, 2014 

Dutch scientists have developed the world's smallest autonomous flapping drone, a dragonfly-like beast with 3-D vision that could revolutionise our experience of everything from pop concerts to farming.

"This is the DelFly Explorer, the world's smallest drone with flapping wings that's able to fly around by itself and avoid obstacles," its proud developer Guido De Croon of the Delft Technical University told AFP.

Weighing just 20 grammes (less than an ounce), around the same as four sheets of printer paper, the robot dragonfly could be used in situations where much heavier quadcopters with spinning blades would be hazardous, such as flying over the audience to film a concert or sport event.

The Explorer looks like a large dragonfly or grasshopper as it flitters about the room, using two tiny low-resolution video cameras, reproducing the 3-D vision of human eyes, and an on-board computer to take in its surroundings and avoid crashing into things.

And like an insect, the drone which has a wingspan of 28 centimetres (11 inches), would feel at home flying around plants.

"It can for instance also be used to fly around and detect ripe fruit in greenhouses," De Croon said, with an eye on the Netherlands' vast indoor fruit-growing business.

"Or imagine, for the first time there could be an autonomous flying fairy in a theme park," he said.

'Real small insects'
Unlike other drones that use rotor blades and can weigh hundreds of times as much, the Explorer has two wings on each side that flap rapidly to create lift. "We got our inspiration from real small insects," De Croon said.

Chief Developer Guido de Croon releases the DelFly Explorer, the world's lightest autonomous flapping drone, during a demonstration at the Delft TU, on January 29, 2014

While smaller "flapping" drones exist, such as the RoboBee developed by students at Harvard University in the US, they are tethered for power, control and processing, and thus far from autonomous.

The Explorer has its own small lithium polymer battery that allows it to fly for around nine minutes, while it "sees" with its onboard processor and a specially-developed algorithm to make instant decisions.

RoboBee

It has wireless analogue video, gyroscopes and a barometer to calculate its height.

Different algorithms would allow it to perform different tasks, and because it is autonomous it could be sent into enclosed spaces such as concrete buildings or mine shafts, where radio control would be impossible, to search for casualties or hazards.

"The DelFly Explorer knows precisely where obstacles are located," said De Croon as the aircraft, built from composite materials including carbon fibre, fluttered towards a wall during a demonstration flight before veering elegantly away in search of another route.

But De Croon admits that humans are not quite able to produce swarms of autonomous robotic insects the size of bees or flies, mainly because of restrictions on battery life.

"Still there are some major challenges... and if I have to put a number on it, I think we are still a few decades away," he laughed.

Jellyfish-powered Ornithopter Drone prepares for lift-off - Video

Inspired by nature and by the aviation pioneers of the early 20th century, scientists in the US said Wednesday they had built the world's first jellyfish drone aircraft.

The tiny, ultra-light lab machine, weighing just 2.1 grammes (0.07 ounces), is the first man-made flying object to hover and move with a motion like that of the jellyfish in water, the inventors believe.

Leif Ristroph

"We were interested first of all in making a robotic insect that would be an alternative to the helicopter," said Leif Ristroph, who works alongside Stephen Childress at New York University's Applied Math Lab.

"Our interest ended up being a little bit weird—it was the jellyfish."

The jellyfish has long been admired by engineers for a simple yet efficient motion, sculpted by millions of years of evolution, that requires just a simple muscle and no brain power, just a primitive nervous system.

It has a bell-like translucent skirt that first billows out and then closes tightly, squirting water out from the small opening to provide itself with movement.

In this case, the aircraft uses four petal-shaped wings, each eight centimetres (four inches) long, that when folded together form a downward-facing "cone."

Stephen Childress

A tiny motor, attached to a crankshaft, causes the wings to push outwards and then downwards, 20 times a second, forcing out air through the bottom of the cone.

The result is an "ornithopter," or flying machine that hovers with great stability, without the need for constant, energy-draining correction.

"If it's knocked over, it stabilises by itself," Ristroph said to reporters.

The craft can change direction by making one of the four wings work harder than the others.

Pioneers of flight
The materials to make the machine are all over-the-counter components—light carbon-fibre ribs to hold the motor and provide the frames of the wings, which are covered by transparent Mylar film—bought at ordinary modelling stores.

Ristroph said he and Childress had been intrigued by film footage of aviation pioneers who had tried to mimick insects to build ornithopters, but lacked the knowledge or materials at the time.

More information: Stable hovering of a jellyfish-like flying machine, Journal of the Royal Society Interface, rsif.royalsocietypublishing.org/lookup/doi/10.1098/rsif.2013.0992