The collision avoidance constraints are prominent as non-convex, non-differentiable, and challenging when defined in optimization-based motion planning problems. To overcome these issues, this paper presents a novel non-conservative collision avoidance technique using the notion of convex optimization to establish the distance between robotic spacecraft and space structures for autonomous on-orbit assembly operations. The proposed technique defines each ellipsoidal- and polyhedral-shaped object as the union of convex compact sets, each represented non-conservatively by a real-valued convex function. Then, the functions are introduced as a set of constraints to a convex optimization problem to produce a new set of differentiable constraints resulting from the optimality conditions. These new constraints are later fed into an optimal control problem to enforce collision avoidance where the motion planning for the autonomous on-orbit assembly takes place. Numerical experiments for two assembly scenarios in tight environments are presented to demonstrate the capability and effectiveness of the proposed technique. The results show that this framework leads to optimal non-conservative trajectories for robotic spacecraft in tight environments. Although developed for autonomous on-orbit assembly, this technique could be used for any generic motion planning problem where collision avoidance is crucial.

By Martin Quin Pollard5 Min ReadWENCHANG, China (Reuters) – China on Tuesday launched a robotic spacecraft to bring back rocks from the moon in the first bid by any country to retrieve samples from the lunar surface since the 1970s, a mission that underscores Chinese ambitions in space.The Long March-5 Y5 rocket, carrying the Chang'e-5 lunar probe, takes off from Wenchang Space Launch Center, in Wenchang, Hainan province, China November 24, 2020. REUTERS/Tingshu WangThe Long March-5, China's largest carrier rocket, blasted off at 4:30 a.m. Beijing time (2030 GMT on Monday) in a pre-dawn launch from Wenchang Space Launch Center on the southern Chinese island of Hainan carrying the Chang'e-5 spacecraft.The Chang'e-5 mission, named after the ancient Chinese goddess of the moon, will seek to collect lunar material to help scientists understand more about the moon's origins and formation. The mission will test China's ability to remotely acquire samples from space, ahead of more complex missions.State broadcaster CCTV, which ran live coverage of the launch, showed images of China National Space Administration staff in blue uniforms applauding and cheering as they watched the spacecraft climbing through the atmosphere, lighting up the night sky.If …

Video Friday is your weekly selection of awesome robotics videos, collected by your Automaton bloggers. We'll also be posting a weekly calendar of upcoming robotics events for the next few months; here's what we have so far (send us your events!): Let us know if you have suggestions for next week, and enjoy today's videos. Built by Engineered Arts, 2 Mesmer Heads perform a synchronised sequence. One is complete with lifelike skin and hair, the other is showing it's mechanical workings.

Artificial intelligence could soon help scientists determine whether other planets harbour alien life. Researchers from Plymouth University's Centre for Robotics and Neural Systems used artificial neural networks (ANNs), which use similar learning techniques to the human brain, in order to estimate the probability of extraterrestrial life on other worlds. They hope that the technology will be used aboard robotic spacecraft on alien-hunting space missions. "We're currently interested in these ANNs for prioritising exploration for a hypothetical, intelligent, interstellar spacecraft scanning an exoplanet system at range," said Christopher Bishop, a PhD student at Plymouth University who led the study. "We're also looking at the use of large area, deployable, planar Fresnel antennas to get data back to Earth from an interstellar probe at large distances. This would be needed if the technology us used in robotic spacecraft in the future."

A privately owned company plans to use robotic spacecraft to launch a series of commercial missions to the moon, some 45 years after NASA s last lunar landing, officials said on Wednesday. Cape Canaveral, Florida-based Moon Express is developing a fleet of low-cost robotic spacecraft that can be assembled like Legos to handle increasingly complex missions, founder and Chief Executive Officer Bob Richards said in an interview. Ultimately the company plans to establish a lunar outpost in 2020 and set up commercial operations on the Moon, mining material and returning it to Earth to sell. The initial spacecraft, known as MX-1E,is a similar size and shape to the R2D2 droid from Star Wars, and is slated to fly before the end of the year aboard a Rocket Lab Electron booster, which launches from New Zealand. Google is offering a top prize of $20 million for the first privately funded team to land a spacecraft on the moon; have it fly, drive or hop at least 1,640 feet (500 meters) and relay pictures and video back to Earth.

How do you get a robot to recognize a surprise? That's a question artificial intelligence researchers are mulling, especially as A.I. begins to change space research. A new article in the journal Science: Robotics offers an overview of how A.I. has been used to make discoveries on space missions. The article, co-authored by Steve Chien and Kiri Wagstaff of NASA's Jet Propulsion Laboratory, Pasadena, California, suggests that autonomy will be a key technology for the future exploration of our solar system, where robotic spacecraft will often be out of communication with their human controllers. In a sense, space scientists are doing field research virtually, with the help of robotic spacecraft.

Two free-flying satellites performed the first autonomous separation and docking for the US on 5 and 6 May. The test was done without any human intervention as the craft flew nearly 500 kilometres above the planet, and could one day lead to robotic spacecraft that are able to repair damaged satellites. The ASTRO (Autonomous Space Transport Robotic Operations) and NextSat satellites together make up the Orbital Express mission. ASTRO waited for 90 minutes, then navigated back to NextSat and docked. Watch a video comprised of still shots from the encounter (.wmv file, 18 MB).

Nasa is planning an ambitious mission that will see a robotic spaceship visit an asteroid to create an orbiting base for astronauts. The robot shipwill pluck a large boulder off the space rock and sling it aroundthe moon, becoming a destination to prepare for futurehuman missions to Mars. Nasa also plans to study the asteroid and test deflection techniques that one day may be necessary to save Earth from a potentially catastrophic collision. Now the space agency has created a mock-up of its robot arm and tested it using a mock asteroid boulder. The robot ship will pluck a large boulder off an asteroid and sling it around the moon, becoming a destination to prepare for future human missions to Mars.

Asteroid mining is coming soon to a planet near you: this planet, and in 2021, to be specific. But NASA's Asteroid Redirect Mission has lots of work to do before that point. Today the space-faring organization issued an official "request for proposal" from four partners on how they would go about creating the robotic spacecraft that would perform the actual asteroid redirection in question. This mission is a bit different from OSIRIS-REx, which recently got underway. The idea there is to go to an asteroid, grab a piece and return it to Earth -- difficult enough, but it wouldn't be the first collection of "live" asteroid matter -- that was already achieved by the Japanese probe Hayabusa a few years ago (an astonishing achievement, by the way).

An ambitious mission that will visit a comet and pluck a boulder from its surface to create an orbiting base for astronauts has been given the final go-ahead. A robot shipwill pluck a large boulder off an asteroid and sling it aroundthe moon, becoming a destination to prepare for futurehuman missions to Mars, the U.S. space agency has revealed. The so-called Asteroid Redirect Mission is estimated to costabout 1.4 billion not including launch costs and is targetedfor liftoff in December 2021. In the Spacecraft Structures Lab at NASA's Langley Research Center, the Asteroid Redirect Mission robotic contact and restraint system is prototyped and tested. A robot ship will pluck a large boulder off an asteroid and drag it into orbit around the moon, becoming a'testbed' for future human missions to Mars, the U.S. space agency has revealed.