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Scientists have been experimenting with four-legged robots for years. They want the ability to use robots like animals to carry heavy loads over difficult areas of land. But providing enough power for those kinds of robots has been a problem. Now, that has changed. Engineers at the Massachusetts Institute of Technology, or MIT, have designed a running robot that operates on batteries. Scientists say their robots will soon be able to run like cheetahs, the fastest land animals on Earth. One difficulty in designing these types of robots continues to be providing power to operate them. These complex machines are still relatively heavy. And their motors require a lot of energy to run. The most powerful of these machines must be connected to an external power source. Others run on gasoline placed in a container on the machine itself. But engineers at MIT have designed a cheetah-like robot that is light enough to run on batteries. The robot weighs just 30 kilograms. Sangbae Kim is the director of the MIT Biomimetics Robotic Lab. He says the robot needs only about 700 watts of power to operate. Mr. Kim says it can jump, run and sprint because of the special motor technology they developed. The robot’s limbs and other parts were made in a three dimensional, or 3-D printer. A strong, light-weight plastic material called Kevlar is used to make the robot parts stronger. One problem researchers have is that the robot’s limbs must support a great amount of force, and sometimes they break.
