Walking with robots
与机器人同行
2020.9

 

A new generation of ambulatory machines is striding to market
新一代能行走的机器正大步迈向市场 

 

经济学人


THEY MIGHT appear cutesy, but a pair of robots that turned up recently at the Ford Motor Company’s Van Dyke Transmission Plant, in Detroit, are practical working machines. They may, indeed, point to the future of automation. Putting robots into factories is hardly a new idea—some 2.4m of them are already at work in plants around the world. But most of these are little more than giant arms, bolted firmly to the ground, that weld and paint things. Those few that have the mobility to manage tasks like delivering components do so by scooting along on wheels. The new devices at Van Dyke are rather different sorts of beasts. They can walk.
虽然可能看上去很蠢萌,最近出现在福特汽车位于底特律的范戴克变速箱工厂(Van Dyke Transmission Plant)的这对机器人可是真正干活的机器。实际上,它们可能显现了自动化的未来。在工厂部署机器人并不是什么新主意,世界各地的工厂中已有约240万台投入使用。但它们大多数都只是牢牢固定在地面上、专事焊接和刷油漆的巨大机械臂。少数能够四下移动来完成传送零件等任务的机器人不过是被放到了轮子上。范戴克工厂的新设备却是截然不同的家伙。它们能行走。
This pair of bright-yellow quadrupeds look a bit like dogs, prompting one to be nicknamed Fluffy and the other Spot (which latter moniker is also the official name given to this model of robot by the firm that manufactures them, Boston Dynamics, a subsidiary of SoftBank). The pair are not there to amuse the factory’s human workers, though, but rather to perform an important task that Ford hopes will save it a ton of money. With laser scanners mounted on their backs, Fluffy and Spot can scamper around the 200,000 square-metre plant collecting data. Those data will be employed to build a detailed computer model of the entire manufacturing operation. This sort of model is called a digital twin, and Ford’s engineers will use it to work out how to rearrange the production line to produce a new gearbox.
这对亮黄色的四足机器人看上去有点像狗,因此一个被昵称为毛球(Fluffy),另一个叫点点(Spot,它们的制造商、软银子公司波士顿动力[Boston Dynamics]也用这个昵称正式命名了这款机器人)。它们可不是去工厂逗工人一乐的,而是执行一项重要任务,福特希望能借此省一大笔钱。毛球和点点的背上扛着激光扫描仪,可以在大约20万平方米大的工厂里到处奔走收集数据。这些数据将用于构建反映整个生产运营过程的详细的计算机模型。利用这种人们称之为数字孪生体的模型,福特的工程师将研判如何重新布置生产线来生产一种新的变速箱。
Over the years, factory plans get out of date as things are moved around and new equipment is brought in. Surveying the transmission plant by hand would take weeks and cost some $300,000. Ford reckons that Fluffy and Spot, which can both climb stairs and crawl into hard-to-reach areas, will cut the time required by half and complete the job for “a fraction of the cost”. Although Ford is leasing the robots, Boston Dynamics has now put them on sale for $75,000 a pop. At that price they would soon pay for themselves doing tasks like the one being undertaken in Van Dyke.
经年累月,工厂里的设备会改变位置,也会引入新设备,因此工厂的布局会过时。对变速箱工厂做人工测绘需要花费数周,耗资约30万美元。毛球和点点能爬楼梯,也能进入人员难以抵达的区域,福特认为使用它们可以将所需时间减半,而且“费用只是原来的一个零头”。尽管福特是租用了这两台机器人,但现在波士顿动力已为它们标出每台7.5万美元的售价。以这个价格,买家能通过让它们完成像范戴克工厂里那样的任务很快收回成本。
The Spot range is the first of Boston Dynamics’s walking robots to be commercialised. More such machines are starting to appear from other firms and research groups. Some are also quadrupeds. Others are bipedal. The two-legged sort can be more agile and, if equipped with arms as well, are better suited to tasks like picking things up or operating controls. What all of these machines have in common is that they represent—forgive the pun—a huge step forward in robot locomotion.
点点系列是波士顿动力研发的步行机器人中第一款商业化的产品。其他公司和研究团队也开始推出更多此类机器。其中一些也是四足的。还有一些是两足的。两足军团会更敏捷,并且如果再装上手臂,就更适合捡拾东西或操作控制之类的任务。所有这些机器的共同点是,它们代表着机器人移动技术向前迈出了一大步(别介意这里还是用了这个双关语)。
Four legs good, two legs better 四条腿好,两条腿更好 If robots are to go where people go, they need to be able to move in the way that people move. Wheels are useless for navigating much of the world—just ask anyone who uses a wheelchair, says Aaron Ames, a robotics expert at the California Institute of Technology (Caltech). “We can make robots walk really well now,” he says. Such robots can, though, look a little odd. When a torso with two legs attached strolls out of Dr Ames’s laboratory it causes a bit of a sensation on Caltech’s campus. But this is something people are going to have to get used to, because many more are coming.
如果机器人要去人去的地方,它们得要能像人那样移动。靠轮子是去不了太多地方的,问问坐轮椅的人就知道了,加州理工学院(Caltech)的机器人专家亚伦·埃姆斯(Aaron Ames)说。“我们现在可以让机器人走得很好。”他说。不过这种机器人看起来有点怪。当一个带着两条腿的躯干从埃姆斯的实验室慢悠悠地走出来时,在加州理工学院的校园里引发了些许轰动。但人们将来不得不要习惯它们,因为有更多正在纷至沓来。
Problems remain, and improvements are needed. “But once we get there, we are going to have millions of walking robots in human environments,” says Jonathan Hurst, co-founder of Agility Robotics, a firm based in Albany, Oregon. It has just launched Digit, a bipedal, two-armed robot which has the look of an ostrich about it. At present, Digit costs $250,000. But it is early days. As more walking robots are put to work their development will accelerate and their production volumes increase, bringing the cost of a machine like Digit down to the tens of thousands of dollars.
问题仍然存在,还需要继续改进它们。“但等问题解决了,我们将在各种人类环境中使用成百上千万台行走机器人。”乔纳森·赫斯特(Jonathan Hurst)说。他是总部位于俄勒冈州奥尔巴尼(Albany)的敏捷机器人公司(Agility Robotics)的联合创始人。这家公司刚刚推出了两足、两臂、看上去像鸵鸟的机器人Digit。目前,Digit售价25万美元。但现在还只是这类产品的初期阶段。随着越来越多的行走机器人投入使用,研发速度将加快,产量将增加,Digit这类机器人的成本会降至几万美元。
This process is similar to the emergence of flying drones. They once cost millions, and had limited uses, until researchers worked out how to make small aircraft hover using multiple co-ordinated rotors. These devices could fly easily and autonomously. Prices fell to $500 or less, and multi-rotor drones are now employed for all manner of jobs, from cinematography to aerial surveying to delivering packages. Some in the field of robotics think walking robots have started down a similar path.
这个过程类似于无人机的兴起。一架无人机的售价曾经高达几百万美元,而且用途有限,直到研究人员找到用多个协同的旋翼让小型飞行器悬停的方法后,情况才发生变化。这样的无人机可以便捷地自主飞行。其价格跌至500美元或更低。如今多旋翼无人机已被用于摄影摄像、航空测量和递送包裹等各种各样的工作任务。机器人行业的一些人士认为行走机器人已经走上了一条类似的道路。
What changed? “We now understand the mathematics of locomotion to a much greater degree,” explains Dr Ames. Old-school walking robots, such as Asimo, a famously cheesy android unveiled in 2000 by Honda, a Japanese carmaker, have stilted gaits. They shuffle along, placing one foot forward, checking their balance, moving the other foot, rechecking their balance, and so on. “When you are walking, you don’t do that,” he says. “Your feet are just coming down and catching yourself.”
那么是什么改变了? “我们对行走动作的数学原理的理解大幅提高了。”埃姆斯解释说。老式的行走机器人走路就像踩高跷,例如日本汽车制造商本田在2000年推出的机器人Asimo就出了名的笨拙。它们前进的时候先迈一只脚,然后检查平衡状态,接着再迈另一只脚,然后再次检查平衡,就这么一步一步地慢慢挪。“人走路的时候不这样,” 他说,“人脚自然落地就能稳住身体。”
Stroll on! 信步前行!
The way that humans walk is sometimes described by biomechanists as controlled falling. Making a stride involves swinging a leg out and placing it down with small subconscious corrections to maintain stability as the mass of the body above it shifts forward. Each leg works like a spring. These movements are predictable, and in recent years researchers have found out how to model them mathematically. Together with better actuators to operate a robot’s limbs, and sensors which can measure things more accurately, these models have made it possible to recreate this style of walking in robots. It does not require any fancy machine learning or artificial intelligence to do so, just good old-fashioned computation, adds Dr Ames.
生物力学家有时将人的行走方式描述为受控的跌落。跨步走时先迈出一条腿,随着上身重量向前移动,通过微弱的潜意识在脚落地时做出矫正以保持稳定。每条腿动起来都像一根弹簧。这些运动是可预测的,并且近年来研究人员找到了对它们进行数学建模的方法。再加上能更好地操纵机器人肢体的致动器,以及能更精确地测量运动的传感器,在机器人身上重现这种行走方式就成为了可能。它不需要任何花哨的机器学习或人工智能,只需做高质量的老式运算就行了,埃姆斯补充说。
The difference between Asimo’s gait and that of the new breed of bot is striking. Whereas Asimo’s chunky legs look leaden, Digit strides confidently along on a lean pair of limbs, happily swinging its arms as it goes. Atlas (pictured), an experimental humanoid made by Boston Dynamics, is more capable still. It can walk, run, jump and even perform backflips. Asimo did a lot of celebrity photo-opps, but it never went into production. Honda quietly stopped work on the project in 2018, to concentrate on more “practical” forms of robotics, such as mobility devices for the elderly. Asimo
与新型机器人在步态上的差异很惊人。Asimo的粗腿看上去很沉重,而Digit用一对纤细的大长腿自信地跨步,边走边协调地摆动双臂。由波士顿动力研发的试验人形机器人Atlas(如图)的功能更加强大。它能行走、奔跑、跳跃甚至后空翻。尽管做了很多高调的宣传,但Asimo从未投产。本田在2018年悄悄地停止了该项目,转而专注于更“实用”的机器人技术,例如老年人出行辅助设备。 
It is easy to conclude, as many do, that these new walking robots simply mimic nature. But that is not quite the case. A quadruped, being a stable platform, is a good starting point from which to design a walking robot. After co-ordinating the four limbs, getting a good balance and fitting a system of vision that lets the robot work out where to put its feet, Spot’s designers ended up with a dog-oid. Michael Perry, head of business development for Boston Dynamics, says that is not surprising because nature has been developing efficient designs for a long time.
很容易就此得出这些新型的行走机器人只是在模仿自然的结论,很多人也正是这么想的。但事实并非完全如此。四足是一种稳定的平台,是设计行走机器人一个合适的出发点。点点的设计师们在协调了机器人的四肢、取到了良好平衡,并安装了能让机器人确定往哪落脚的视觉系统后,最终创造出了一款狗形机器人。波士顿动力的业务发展主管迈克尔·佩里(Michael Perry)说这并不奇怪,因为大自然一直都在发展有效的设计。
Another example of art evolving to imitate nature occurred during the design of Digit. This inherited its ostrich looks from Cassie, a two-legged torso which Agility sold to a number of research groups. Cassie’s developers had to find a way to stop some of the robot’s actuator motors from working against each other. Their solution turned out to look like a pair of bird’s legs.
工艺设计不断演变去模仿自然的另一个例子可以在Digit的设计过程中找到。Digit那鸵鸟式的外观传承自机器人Cassie,这款由敏捷机器人公司设计的双足加躯干机器人卖给了许多研究团队。Cassie的开发人员必须找到一种方法来阻止机器人的一些致动器马达相互对抗。他们拿出的解决方案看上去像是鸟的两条腿。
Cassie subsequently acquired arms and evolved into Digit as the result of the engineers’ attempts to solve another problem. When it swung a leg forward Cassie’s body twisted a little, which sometimes caused the robot to fall over if it was walking quickly. In nature, some animals use tails to improve their balance when manoeuvring at speed. Borrowing this idea, Agility’s researchers attached a pair of tail-like appendages, one on each side of the robot’s torso, to improve its mobility. That worked. Then they turned the appendages into a pair of arms. These can catch the robot should it fall, and help it get up again.
后来,Cassie因为工程师要解决另一个问题而获得了双臂,演变成了Digit。Cassie向前迈腿时,身体会轻微扭转,有时会导致它在快速行走时跌倒。在自然界中,有些动物在快速运动时会利用尾巴来改善平衡。敏捷机器人公司的研究人员借鉴了这一点,在Cassie躯干的两侧各加了一个尾状附件,以提高其行动稳定性。这个设计挺管用。后来他们把这对附件变成了两条手臂。如果机器人摔倒了,它能用它们撑住身体并站起来。
The arms can perform other useful tasks, too, such as moving boxes in a warehouse. Digit can carry up to 20kg. Distributing and delivering goods is likely to be an important application for walking robots, reckons Dr Hurst, especially now that e-commerce has boomed as a result of restrictions imposed in the wake of covid-19. Some automated distribution centres are set up for conventional fixed and wheeled robotic systems, but these have usually been built this way from scratch. Most warehouses are designed around people. Robots with legs, which move in a similar way to human workers, would fit right in.
手臂也可以执行其他有用的任务,比如在仓库中搬箱子。Digit最大承重20公斤。赫斯特认为,配送货物很可能会是行走机器人的一个重要应用,尤其是新冠肺炎爆发后实施的限制措施推动了电子商务蓬勃发展。一些自动化配送中心围绕常规的固定式和轮式机器人系统而建,但它们通常从一开始就是这么设计的。大多数仓库都是围绕人设计的。有腿的机器人能像人类工人那样移动,因此可以直接参与进去。
With further development, walking robots will undertake more complex tasks, such as home deliveries. Ford is working on this with a Digit robot that rides in the back of a van. Though robots with wheels already make some deliveries, reaching many homes is tricky, and may involve climbing steps or stairs. “Legs are how you would want to get up to most front doors to deliver a package,” observes Dr Hurst.
随着进一步的改进,行走机器人将承担起送货上门等更复杂的任务。福特正在做这方面的探索,在它的货车车厢里带上一台Digit机器人。尽管轮式机器人已经承担了一些送货的工作,但很多地方要送货上门还有困难,而且还可能需要上下台阶或楼梯。“要把包裹送到大多数人的家门口都得用腿。”赫斯特说。
Exactly how this might be done remains to be seen. Unless they are on a preprogrammed mission, most mobile robots require an operator to provide basic instructions to, say, proceed to a certain point. The robot then walks there by itself, avoiding obstacles and climbing or descending steps and stairs along the way. This means a walking robot making door-to-door deliveries might need some kind of digital map of the neighbourhood, to know in advance the paths it can traverse and the flower beds it should avoid. That might involve a big data-acquisition effort, much like those used to build digital maps for driverless cars. Similarly, in a factory or a warehouse, a walking robot would need to be shown the ropes by a human being before it was let loose to work on its own.
具体如何实现还要拭目以待。除非是在执行预先编程的任务,否则大多数行走机器人都需要操作员提供基本指令,比如前往某个特定地点。然后,机器人自己走去那里,在沿途避开障碍物,上下台阶和楼梯。这意味着送货上门的行走机器人可能需要某种社区数字地图,以便提前知道可以穿越的道路和需要绕开的花坛。这可能需要大量的数据采集工作,就像为无人驾驶汽车制作数字地图一样。同样,在工厂或仓库中,行走机器人将需要先接受人类的指导才能开始自行工作。
Self determination 自主自决
A fully autonomous robot that could walk into an unknown environment and decide for itself what it needed to do remains a long way off. One of the hardest tasks for such a device would be caring autonomously for someone at home. The robot would have to be able to make numerous complex decisions, such as administering the correct medicine, deciding whether or not to let strangers into the house or knowing when to take the dog for a walk. Yet many roboticists think they will get there, or at least close to it, one day.
要研发出完全自主、能走进未知环境并自己决定该做什么的机器人,还有很长一段路要走。对于这种机器来说,最艰巨的任务之一将是在家中自主照顾人。机器人将必须能够做出大量复杂的决定,比如正确用药,决定是否让陌生人进屋,或者知晓何时该去遛狗了。不过,许多机器人专家都认为机器人有朝一日将能做到这些,或者至少接近于做到。
In the meantime, the new generation of robots now being developed will keep building up the machines’ capabilities. At Boston Dynamics Mr Perry reckons that, besides surveying, Spot will find many roles in inspection and maintenance. Such robots can, for instance, enter hazardous environments like electrical substations without them having to be taken off the grid, as is necessary whenever a human engineer goes inside.
与此同时,正在开发的新一代机器人将继续加强功能。波士顿动力的佩里认为,除测绘外,点点还将在检查和维护工作中发挥多种作用。例如,可以让这样的机器人进入变电站这类危险的环境,就不必像人类工程师进入变电站时那样必须先切断设施电源。
Instead of just looking for problems, Spot’s next trick will be to take action to resolve them, such as throwing a switch or turning a valve. It will do this with a single manipulator arm which makes it look less like a dog and more like a long-necked Brachiosaurus. A prototype of this configuration is already running around the company’s offices, opening and shutting doors. 除了要找出问题,点点的下一个本领将是采取行动解决问题,例如扳动开关或转动阀门。它将用单条机械臂来完成这样的操作,这会让它看起来不大像狗了,而更像脖子长长的腕龙。这种构造的一个原型已经在波士顿动力的办公区使用,负责开门关门。 This version of Spot should go on sale next year. As for Atlas, Boston Dynamics’s humanoid, that is currently too expensive to spawn a commercial version. But the lessons being learnt from it will help provide the engineering needed for other robots to come, says Mr Perry.
这个版本的点点应该会在明年上市。至于波士顿动力的人形机器人Atlas,它的价格目前还过于昂贵,不能量产商用版。但从它身上吸取的经验教训将有助于提供研发其他机器人所需的工程技术,佩里说。
Some of these walking robots of the future may not be deployed on this world. At Caltech, Dr Ames thinks robots with legs will have advantages in planetary exploration—negotiating difficult terrain and entering caves, for example. Meanwhile, back on Earth, he and some colleagues at other institutions are using the new knowledge of robotic locomotion to develop lightweight prosthetic devices for those unable to walk easily, and powered exoskeletons for those who cannot walk at all. In a world not made for wheels, this raises the tantalising prospect that walking robots will one day help rid the world of wheelchairs.
有些未来的行走机器人可能不会用在地球上。加州理工学院的埃姆斯认为带腿的机器人在行星探索中会具有优势,比如它们可以穿越困难的地形、深入洞穴。与此同时,在地球上,埃姆斯和其他机构的一些同事正在利用机器人运动的新知识为行走不便的人开发轻巧的假肢设备,为完全无法行走的人开发动力外骨骼。在一个不能靠轮子通行无阻的世界里,这展现了诱人的前景:有朝一日,行走机器人将让这个世界不再需要轮椅。