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发表时间:2018-09-14内容来源:VOA英语学习网

TED设计:Raffaello D'Andrea: Meet the dazzling flying machines of the future

What started as a platform for hobbyistsis poised to becomea multibillion-dollar industry.Inspection, environmental monitoring,photography and film and journalism:these are some of the potentialapplications for commercial drones,and their enablersare the capabilities being developedat research facilities around the world.

For example, before aerialpackage deliveryentered our social consciousness,an autonomous fleet of flying machinesbuilt a six-meter-tall towercomposed of 1,500 bricksin front of a live audienceat the FRAC Centre in France,and several years ago,they started to fly with ropes.By tethering flying machines,they can achieve high speedsand accelerations in very tight spaces.They can also autonomously buildtensile structures.Skills learned include how to carry loads,how to cope with disturbances,and in general, how to interactwith the physical world.

Today we want to show you somenew projects that we've been working on.Their aim is to push the boundaryof what can be achievedwith autonomous flight.

Now, for a system to functionautonomously,it must collectively know the locationof its mobile objects in space.Back at our lab at ETH Zurich,we often use external camerasto locate objects,which then allows us to focus our effortson the rapid developmentof highly dynamic tasks.For the demos you will see today, however,we will use new localization technologydeveloped by Verity Studios,a spin-off from our lab.There are no external cameras.Each flying machine uses onboard sensorsto determine its location in spaceand onboard computationto determine what its actions should be.The only external commandsare high-level onessuch as "take off" and "land."

This is a so-called tail-sitter.It's an aircraft that triesto have its cake and eat it.Like other fixed-wing aircraft,it is efficient in forward flight,much more so than helicoptersand variations thereof.Unlike most otherfixed-wing aircraft, however,it is capable of hovering,which has huge advantagesfor takeoff, landingand general versatility.There is no free lunch, unfortunately.One of the limitations with tail-sittersis that they're susceptibleto disturbances such as wind gusts.We're developing new controlarchitectures and algorithmsthat address this limitation.The idea is for the aircraft to recoverno matter what state it finds itself in,and through practice,improve its performance over time.

(Applause)

OK.

When doing research,we often ask ourselvesfundamental abstract questionsthat try to get at the heart of a matter.For example, one such question would be,what is the minimum number of moving partsneeded for controlled flight?Now, there are practical reasonswhy you may want to knowthe answer to such a question.Helicopters, for example,are affectionately knownas machines with a thousand moving partsall conspiring to do you bodily harm.It turns out that decades ago,skilled pilots were able to flyremote-controlled aircraftthat had only two moving parts:a propeller and a tail rudder.We recently discoveredthat it could be done with just one.

This is the monospinner,the world's mechanically simplestcontrollable flying machine,invented just a few months ago.It has only one moving part, a propeller.It has no flaps, no hinges, no ailerons,no other actuators,no other control surfaces,just a simple propeller.Even though it's mechanically simple,there's a lot going onin its little electronic brainto allow it to fly in a stable fashionand to move anywhere it wants in space.Even so, it doesn't yet havethe sophisticated algorithmsof the tail-sitter,which means that in orderto get it to fly,I have to throw it just right.And because the probabilityof me throwing it just right is very low,given everybody watching me,what we're going to do insteadis show you a videothat we shot last night.

(Laughter)

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If the monospinneris an exercise in frugality,this machine here, the omnicopter,with its eight propellers,is an exercise in excess.What can you do with all this surplus?The thing to noticeis that it is highly symmetric.As a result, it is ambivalentto orientation.This gives it an extraordinary capability.It can move anywhere it wants in spaceirrespective of where it is facingand even of how it is rotating.It has its own complexities,mainly having to dowith the interacting flowsfrom its eight propellers.Some of this can be modeled,while the rest can be learned on the fly.Let's take a look.

(Applause)

If flying machines are goingto enter part of our daily lives,they will need to becomeextremely safe and reliable.This machine over hereis actually two separatetwo-propeller flying machines.This one wants to spin clockwise.This other one wantsto spin counterclockwise.When you put them together,they behave like onehigh-performance quadrocopter.If anything goes wrong, however —a motor fails, a propeller fails,electronics, even a battery pack —the machine can still fly,albeit in a degraded fashion.We're going to demonstrate this to you nowby disabling one of its halves.

(Applause)

This last demonstrationis an exploration of synthetic swarms.The large number of autonomous,coordinated entitiesoffers a new palettefor aesthetic expression.We've taken commercially availablemicro quadcopters,each weighing lessthan a slice of bread, by the way,and outfitted themwith our localization technologyand custom algorithms.Because each unitknows where it is in spaceand is self-controlled,there is really no limit to their number.

(Applause)

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Hopefully, these demonstrationswill motivate you to dream upnew revolutionary rolesfor flying machines.That ultrasafe one over there for examplehas aspirations to becomea flying lampshade on Broadway.

(Laughter)

The reality is that it isdifficult to predictthe impact of nascent technology.And for folks like us, the real rewardis the journey and the act of creation.It's a continual reminderof how wonderful and magicalthe universe we live in is,that it allows creative, clever creaturesto sculpt it in such spectacular ways.The fact that this technologyhas such huge commercialand economic potentialis just icing on the cake.

Thank you.

(Applause)

来自:VOA英语网 文章地址: https://www.veryv.net/html/20180914/Raffaello-DAndrea-Meet-the-dazzling-flying-machines.html