Devices that help people walk were once thought to be difficult, if not impossible, to design. Until recently, such a device required electricity from an external power supply. Now, American scientists have built a small, wearable addition to normal shoes. Their new invention eases the load on muscles in the leg and makes walking easier.
人们曾经认为设计出帮助人类行走的设备非常难，甚至不可能。截至目前这类设备都需要外部电源提供电力。而现在，美国科学家制造了一种适合普通鞋的小型可穿戴附加设备。他们的新发明可以减轻腿部肌肉的负荷，让行走变得更加容易。
Steven Collins and Greg Sawicki are biomedical engineers. They both studied how human beings walk. They found that our ankles and calves perform motions similar to a spring joined to a clutch. In an automobile, a clutch is used to connect and disconnect a driving or driven part of an engine or other piece of equipment. The researchers found that the human body parts are able to both store and release energy, just like a spring.
史蒂芬·柯林斯（Steven Collins）和格雷格·萨维奇（Greg Sawicki）都是生物医学工程师。他们都在研究人类如何行走。他们发现，我们的脚踝和小腿进行运动的原理与离合器上的弹簧类似。在汽车上，离合器被用于连接或断开发动机或其它设备的驱动部分。研究人员发现，人体的这些部分（指脚踝和小腿）能够像弹簧一样储存和释放能量。
Steven Collins works with Carnegie Mellon University in Pennsylvania. Greg Sawicki is with North Carolina State University. He spoke to VOA on Skype.
柯林斯就职于宾夕法尼亚州的卡内基·梅隆大学。萨维奇就职于北卡罗来纳州立大学。他通过Skype对美国之音表示。
"We found in basic science experiments that that system, your calf and Achilles tendon, works a lot like a catapult. So, the muscle holds on to the tendon and your body actually stretches your Achilles tendon quite a bit and then stores the energy in the tissue and then it's given back to propel you forward in the world."
他说，“我们发现在基础科学实验中，小腿和跟腱这一系统就像弹射器一样工作。肌肉附在跟腱上，当身体伸展开跟腱时，就把能量储存到人体组织中，之后再释放出来推动人们向前行进。”
Mr. Sawicki says he and Mr. Collins designed a mechanical device that performs the same kind of energy ‘give-and-take' outside the body. Their new ankle exoskeleton is made of carbon fiber and metal. It connects to ordinary shoes and takes over part of the work of walking. Mr. Sawicki says the device reduces the amount of energy required for walking by as much as seven percent.
萨维奇表示，他和柯林斯设计出一种机械装置，能够在体外进行同样的能量储存与释放。他们这种新的外骨脚踝是用碳纤维和金属制成，可以附加到普通鞋子上并承担部分行走工作。萨维奇先生表示，这种装置可以让行走所需能量降低7%。
The unpowered ankle exoskeleton can help people walk farther with the same amount of energy. It also can restore normal movement for individuals who have trouble walking.
这种无动力外骨脚踝可以帮助人们用相同能量走得更远。它还能让走路困难的人恢复正常运动。
Mr. Sawicki says it takes only a few minutes for someone to get used to the ankle exoskeleton. He says the wearer quickly learns to use less muscle energy, letting the device do much of the work.
萨维奇先生表示，人们只需要几分钟就能适应这种外骨脚踝。他说，佩戴者很快能学会使用更少肌肉能量，而让设备承担很多工作。
"You really don't notice it until when you take it off. And when you take it off you realize that it was there and giving you the boost."
他说：“你根本意识不到，直到把它脱下来，你才会感觉到它在给予你帮助。”
Mr. Sawicki says the device is mainly meant for people recovering from a surgery operation or a stroke. He adds that anyone who spends a lot of time walking, like hospital workers and policemen, could use the device.
萨维奇先生表示，这种设备主要用来帮助人们从外科手术或中风中康复。他补充说，医院工作人员和警察等长时间行走的人群也可以使用这种设备。
There are no plans to make the ankle exoskeleton available to the general public. But the inventors say some manufacturers have expressed interest in the device.
目前这种外骨脚踝还没有计划面向公众销售。但是开发者表示，一些厂商已经对此表示了兴趣。
I'm Jonathan Evans.
我是乔纳森·埃文斯。(51VOA.COM对本文翻译保留全部权利，未经授权请勿转载，违者必究！)