Robots Compilation Dr. Thomas Lairson
MIT uses 4D maps to help robot teams navigate moving obstacles
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MIT uses 4D maps to help robot teams navigate moving obstacles
Audi drives repairs with telepresence robots' help 
A new, decentralized planning algorithm for teams of robots factors in moving obstacles. Credit: Christine Daniloff/MIT
By Katherine Noyes IDG News Service | Apr 21, 2016 4:35 PM PT It's one thing to keep robots from crashing into fixed obstacles like walls or furniture, but preventing collisions with other moving things is a much tougher challenge. Targeting teams of robots working together, MIT on Thursday announced a new algorithm that helps robots avoid moving objects. Planning algorithms for robot teams can be centralized, in which a single computer makes decisions for the whole team, or decentralized, in which each robot makes its own decisions. The latter approach is much better in terms of incorporating local observations, but it's also much trickier, since each robot must essentially guess what the others are going to do. MIT's new algorithm takes a decentralized approach and factors in not just stationary obstacles but also moving ones. Each robot uses its own observations to map out an obstacle-free region in its immediate environment. It then passes that map to its nearest neighbors. When a robot receives a map from a neighbor, it calculates the intersection of that map with its own and passes that on to other neighbors. Because each robot communicates only with its close neighbors, the bandwidth required for communications is greatly reduced, particularly when there are a lot of robots. And each robot ends up with a map that reflects all of the obstacles detected by the whole team. The algorithm accounts for obstacles in motion by including time as a fourth mapping dimension. With that dimension included, it describes how a three-dimensional map would have to change to accommodate the obstacle’s change of location over a span of a few seconds. In simulations involving squadrons of mini helicopters, the algorithm came up with the same flight plans that a centralized version did but allowed for small variations as conditions required. “It’s a really exciting result, because it combines so many challenging goals,” said Daniela Rus, a professor in MIT’s Department of Electrical Engineering and Computer Science and director of the Computer Science and Artificial Intelligence Laboratory. “Your group of robots has a local goal, which is to stay in formation, and a global goal, which is where they want to go or the trajectory along which you want them to move," Rus explained. "You allow them to operate in a world with static obstacles but also unexpected dynamic obstacles, and you have a guarantee that they are going to retain their local and global objectives.” Each robot updates its map several times per second, calculating the trajectory that will maximize both local and global objectives. To simulate environments in which humans and robots work together, the researchers are also testing a version of their algorithm on wheeled robots whose goal is to collectively carry an object across a room where humans are also moving. They'll present their algorithm next month at the International Conference on Robotics and Automation. The Economist Robotic surgeryWho wields the knife?A machine carries out an operation almost unaidedMay 7th 2016 | From the print edition 
THEY don’t drink, they don’t get tired and they don’t go on strike. To hospital managers, the idea of robots operating on patients without human intervention is an attractive one. To patients, though, the crucial question is, “are they better than human surgeons?” Surgery is messy and complicated. A routine operation can become life-threatening in minutes. Such considerations have meant that the role of robots in operating theatres has been limited until now to being little more than motorised, precision tools for surgeons to deploy—a far cry from the smart surgical pods and “med-bays” of science fiction. But a paper published this week in Science Translational Medicine, by Peter Kim of the Children’s National Health System in Washington, DC, and his colleagues, brings the idea of real robot surgeons, operating under only the lightest of human supervision, a step closer. Though not yet let loose on people, it has successfully stitched up the intestines of piglets. To build their robodoc, dubbed the Smart Tissue Autonomous Robot (STAR), Dr Kim and his team fitted a robotic arm with an articulated suturing tool and a force sensor to detect the tension in the surgical thread during the operation. They equipped the arm with cameras that could create a three-dimensional image, to guide it as it deployed the tool, and also a thermal-imaging device to help distinguish between similar-looking tissues. A computer program written by the team controlled the arm. This had a repertoire of stitches, knots and manoeuvres that permitted it to plan and carry out a procedure, known as anastomosis, which involves sewing together two parts of a bodily tube.
No pig in a poke Before each of the trial operations, the team anaesthetised a piglet and opened its abdomen to expose part of its small intestine. They then severed this and highlighted pertinent areas with fluorescent dye, to help guide the arm. Under a surgeon’s supervision, STAR sewed the piglet’s gut together again. In the four operations reported in the paper it carried out about 60% of the procedure without human intervention, and the rest with only minor adjustments to its stitches. Since the team submitted their results for publication, however, they say STAR has successfully completed the entire process unaided. Comparing STAR’s work with that of experienced surgeons operating both with and without the assistance of existing robotic tools, Dr Kim and his colleagues reckoned STAR’s stitches were more evenly spaced and the sutured gut less leaky. None of the pigs suffered complications. STAR did, it is true, take much longer than a human surgeon would to create the suture. It averaged 50 minutes for the operation, whereas a person would take about eight. But that will surely get faster. And even if STAR never quite matches a human being at work for speed, the better final product it seems to deliver would, if translated into regular clinical practice, reduce readmission rates. For now, STAR remains a tool rather than a truly autonomous agent. But such autonomy is probably not far away. Dr Kim hopes, for example, that a souped-up version will soon be able to remove an appendix without any assistance from doctors. STAR’s existence does, though, highlight two questions being raised more and more in what is an increasingly robotised society. These are: “will people trust robots with their lives?” and, “who is liable if something goes wrong?” The answer to the first will probably depend on the level of supervision the machines are subject to. It would not take much, for example, to turn airliners into drones, but passengers are reassured by the presence of a flight crew, so this is unlikely to happen soon. The same will probably be true of surgical robots, however good they become. In answer to the second, the lawyers are already circling. Intuitive Surgical, a maker of surgical robots based in Sunnyvale, California, has been on the receiving end of lawsuits alleging (which the firm denies) that surgeons were inadequately trained to use its machines or that the robots were defective. Machines may get the better of humans in the operating theatre, but the courtroom will also determine how fast they spread. MIT Technology Review Directory: tlairson -> ibtech tlairson -> The South China Sea Is the Future of Conflict tlairson -> Nyt amid Tension, China Blocks Crucial Exports to Japan By keith bradsher published: September 22, 2010 tlairson -> China Alters Its Strategy in Diplomatic Crisis With Japan By jane perlez tlairson -> The Asia-Pacific Journal, Vol 11, Issue 21, No. 3, May 27, 2013. Much Ado over Small Islands: The Sino-Japanese Confrontation over Senkaku/Diaoyu tlairson -> Chapter 5 The Political Economy of Global Production and Exchange tlairson -> Chapter IX power, Wealth and Interdependence in an Era of Advanced Globalization tlairson -> Nyt india's Future Rests With the Markets By manu joseph published: March 27, 2013 tlairson -> Developmental State tlairson -> The Economist Singapore The Singapore exception To continue to flourish in its second half-century, South-East Asia’s miracle city-state will need to change its ways, argues Simon Long ibtech -> History of the Microprocessor and the Personal Computer, Part 2 Download 5.27 Mb. Share with your friends:
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