Tag: 上海水磨是怎么个流程

Replacing hard parts in soft robotsReplacing hard parts in soft robots

first_imgIn recent years, an entirely new class of robot — inspired by natural forms and built using soft, flexible elastomers — has taken the field by storm, with designs capable of gripping objects, walking, and even jumping.Yet despite those innovations, so-called “soft” robots still carried some “hard” parts.In particular, said Philipp Rothemund, a doctoral student working in the lab of Woodford L. and Ann A. Flowers University Professor George Whitesides, the inflation and deflation of the robots was typically controlled by off-the-shelf pneumatic valves — until now.Rothemund and postdoctoral fellow Daniel Preston have created a soft valve that could replace such hard components, and could lead to the creation of entirely soft robots. The valve’s structure can also be used to produce unique, oscillatory behavior and could even be used to build soft logic circuits. The valve is described in a recently published paper in Science Robotics.In addition to Rothemund and Preston, the study is co-authored by Alar Ainla, Lee Belding, and Sarah Kurihara from the Department of Chemistry and Chemical Biology, Zhigang Suo from the Kavli Institute for Bionano Science & Technology, and Whitesides. Related A new grasp on robotic glove Soft robotic arm acts as extension of human hand New device gives deep-sea researchers better dexterity for embracing delicate sea life Soft, lightweight robotic glove assists with grasping objects independently “People have built many different types of soft robots … and all of them in the end are controlled by hard valves,” Rothemund said. “Our idea was to build these control functions into the robot itself, so we wouldn’t need these hard, external parts anymore. This valve combines two simple ideas — first, the membrane is similar to ‘popper’ toys, and the second is that when you kink these tubes, it’s like when you kink a garden hose to block the water flow.”The valve demonstrated by Preston and Rothemund is built into a cylinder that is separated by a silicone membrane, creating an upper and lower chamber.Pressurizing the lower chamber forces the membrane to pop up, and releasing the pressure causes it to pop back down to its “resting” state. Each chamber also contains a tube that can be kinked when the membrane switches orientations, effectively turning the valve on or off.“Whichever direction it’s in, it’s kinking a tube above or below,” Preston said. “So when it’s popped down, the bottom tube is kinked, and there’s no air flow through the bottom tube. When the membrane pops up, the top tube is kinked, the bottom tube will unkink, and air can flow through the bottom tube. We can switch back and forth between these two states … to switch the output.”,In some ways, Preston and Rothemund said, the valve represents a new approach to soft robotics.While most work in the field thus far has focused on function — building robots that can grip or act as soft surgical retractors — Rothemund and Preston see the valve as a key component that could be used in any number of devices.“The idea is that this works with any soft actuator,” Rothemund said. “This doesn’t answer the question of how do you make a gripper, but it takes a step back and says many soft robots work on the same principle of inflation and deflation, so all those robots could use this valve.”Preston and Rothemund were able to adapt the valve to perform some actions, such as gripping an object, autonomously.In one demonstration, Rothemund explained, the valve was built into a multifingered gripper, but a small vent was added to allow air pressure to escape the valve’s bottom chamber. When the gripper was lowered onto a tennis ball, however, the vent was closed, causing the bottom chamber to become pressurized, activating the valve, and putting the gripper into action.“So this integrates the function into the robot,” he said. “People have made grippers before, but there was always someone standing there to see that the gripper was close enough to activate. This does that automatically.”The team was also able to build a “feedback” system that, when fed by a single, steady pressure, caused the valve to rapidly oscillate between states.Essentially, Preston said, the system fed air pressure through the top chamber and into the bottom. When the valve popped into the raised position, it cut off the pressure, allowing the bottom chamber to vent, releasing the pressure and causing the membrane to return to the down position, starting the cycle again.“We took advantage of the fact that the pressure that causes the membrane to flip up is different than the pressure that’s required for it to flip back down,” he explained. “So when we feed the output back into the valve itself, we get this oscillatory behavior.”Using that behavior, the team was able to build a simple “inchworm” robot capable of locomotion based on a single valve receiving a single input pressure.“So with one constant pressure, we were able to get this walking motion,” Preston said. “We don’t control this walking at all — we just input a single pressure and it walks by itself.”Going forward, Rothemund said, more work needs to be done to further refine the valve so it can be optimized for various uses and various geometries.“This was just a demonstration with the membrane,” he said. “There are many different geometries that show this type of bistable behavior … so now we can actually think about designing this so it fits in a robot, depending on what application you have in mind.”Preston also hopes to explore whether the valve — because it is always in one of two states — could be used as a type of transistor to form logic circuits.“It’s kind of like a transistor in a way,” he said. “You can have an input pressure come in and switch what the output is going to be … in that sense we could think about this almost like a building block for a completely soft computer.”This research was supported with funding from the Department of Energy, Office of Basic Energy Sciences, Division of Materials Science and Engineering, the Harvard Materials Research Science and Engineering Center, the National Science Foundation, the Swedish Research Council, and the Natural Sciences and Engineering Research Council of Canada Postdoctoral Fellowship.last_img read more

Penultimate week sees just three race wins at CheltenhamPenultimate week sees just three race wins at Cheltenham

first_imgRankTipsterRace WinsPoints 1Sarah Shannon – AppBet313.69 2Alan Alger – Betway311.41 3Jacob Johns – Easyodds37.72 4Phillip Anderson – Before The Off36.17 5Ciaran O’Brien – William Hill35.29 6bettingexpert1.624.53 7Ben Cleminson – Square in the Air14.50 8John Hill – Coral24.25 9Alex Donohue – Ladbrokes24.11 10Michael Shinners – Sky Bet24.00 11Stuart Tilly – Argyll Entertainment14.00 12Darren Moore – Betting Gods23.66 13Conor White – BetBright33.62 14Trevor Keane – Sportego23.50 15Harry Lang – Pinnacle13.50 16Matthew Hulmes – Betfred23.25 17Timeform1.853.20 18Paddy Power13.00 19Russell Yershon11.88 20Edward Rycroft – LeoVegas21.82 21Charlie McCann – BetVictor11.75 22Stephen Power – @racingblogger21.69 23John Cruces – Dafabet11.25 24Michael Whittle – Team FA10.91 25Ed Nicholson – Unibet10.73 26Gerry Murray – 32Red10.44 27Bradley Gibbs – Bookmaker Ratings10.20 28Ged Colleypriest – Ball Street00.00 After proving to be an unhappy hunting ground for our experts at the Festival five weeks ago, Cheltenham threw up just a trio of winners across seven races in yesterday’s Tipster Challenge.In the penultimate week of the 2016/17 challenge, sponsored by Betting Gods, Ball Street Partnerships Director Ged Colleypriest failed to find a winner, while bettingexpert’s Stephen Harris returned an untimely low score of 1.63 points to harm his chances of finishing in the top five.Timeform did at least record a pair of victories, including a 3/1 win for Doing Fine, for a week-high total of 3.53 points. They will be looking to overtake the likes of Betfred and Pinnacle in next week’s finale.Race Winners at Cheltenham:William Henry – 8/15Henryville – 7/1Political Quiz – 9/1Doing Fine – 3/1Iora Glas – 8/1Mick Thonic – 13/8Silverhow – 7/2Tipster Challenge 2016/17 Leaderboard Better Collective moves fast to mitigate COVID-19 as esports journey begins May 15, 2020 Share ‘Better for Bettors’: Better Collective’s formalised approach to sustainable development June 15, 2020 Sharecenter_img bettingexpert, Timeform and a rotation of guests will be providing expert tips for a specific Wednesday race meet.We will keep record of points won each week and the number of race wins for each.The guests will compete individually, with their points going up against the average totals for bettingexpert and Timeform.The new tips will be published on Wednesday ahead of the race meet, and the results will be available on Thursday.For the competition, we will assume that all selections are backed with 1 point.Lost tips will count as 0 and won bets will be added to the leaderboard at SP value.For example, if bettingexpert backs a winning horse at 8/1, they will get 8 points. Better Collective secures esports vision by acquiring HLTV.org for €35m February 28, 2020 Related Articles StumbleUpon Submitlast_img read more

‘You’ll see the best of Hazard later’‘You’ll see the best of Hazard later’

first_imgWorld Cup ‘You’ll see the best of Hazard later’ – Eden predicts strong World Cup Sacha Pisani 03:52 6/19/18 FacebookTwitterRedditcopy Comments(0) Hazard-cropped Getty Images World Cup Belgium v Panama Panama Belgium Eden Hazard Thibaut Courtois praised Eden Hazard during the pre-match build-up and the Belgium superstar replied following the team’s Group G victory. Eden Hazard joked his best will come later in the World Cup after his important role in Belgium’s 3-0 win over Panama on Monday.Hazard combined with Kevin De Bruyne to set up Romelu Lukaku’s first goal and teed up the Manchester United striker for his second, as title contenders Belgium opened their Group G campaign in tough but victorious fashion at Fisht Stadium in Sochi.A lot of the pre-match build-up centred on Hazard and his form, with Belgium and Chelsea team-mate Thibaut Courtois saying the reported Real Madrid target was in the best shape of his career. Article continues below Editors’ Picks Out of his depth! Emery on borrowed time after another abysmal Arsenal display Diving, tactical fouls & the emerging war of words between Guardiola & Klopp Sorry, Cristiano! Pjanic is Juventus’ most important player right now Arsenal would be selling their soul with Mourinho move Asked about Courtois’ comments afterwards, a smiling Hazard said: “He wants to give me confidence!”No, I do feel in a good moment. The pre-World Cup was good and I had some good games in the friendlies. I was good today but I can do better. I think you will see the best of Eden Hazard later.He added: “I can do better. [I got a] nice assist, but usually when I pass to Romelu, he scores, so it’s not that difficult to get an assist sometimes. It was a good performance by the team, but we can all do better.”Hazard walked through the mixed zone with his left leg strapped after receiving some physical treatment from debutants Panama.The 27-year-old attacker was targeted by Panama throughout the first half, the Belgian superstar noticeably hobbling after a robust challenge.Hazard, unperturbed, emerged from the interval and helped inspire Belgium following a frustrating and scoreless opening period, Panama’s stubborn resistance broken by Dries Mertens’ stunning volley at the start of the second half.”We knew it would be physical. People were saying that Belgium would win every game easily but it’s not like this. They have good players, strong players, they play to their strengths, and that’s why we had some little problems in the first half. But at the end of the game, we won 3-0, so we have to be happy,” Hazard continued.”I think they gave everything. When the ball was between a Panama and Belgium player, the Panama player won the duel. In this type of game, you need to be stronger than the team in front of you and we were in the second half.”We spoke at half-time and said that we need to keep playing. The pitch was a little bit slow, so it wasn’t easy to find other players or play the ball quickly. But we kept trying and we scored some goals in the end.”last_img read more