As NASA's 30-year space shuttle programme draws to a close, engineers at the space agency are focusing on building advanced robots that will delve deeper into space.

Robots have been a part of NASA's entire shuttle programme, being used as various robotic arms onboard most space shuttles, as well as the International Space Station. The robotic arms moved massive payloads, carried astronauts during spacewalks and did the "heavy lifting" during the construction of the space station .

"You see this arm, this delicate looking arm, grabbing these huge payloads and moving them around with great precision," said Brian Roberts, a robotics specialist at Goddard Space Flight Centre. "It really was ground breaking."

And while Roberts said the shuttle program, as well as the build out and operation of the space station, was a great test bed for space robotics, it turned out that robots were a critical ingredient for both programmes.

"I don't think the space shuttle programme could have done a great deal of their missions without robotics," he added. "You just couldn't have maintained the Hubble [Space Telescope] without robotics. There's no way even three or four astronauts floating around could have done that, and there's no way we could have built the space station without robotics. Just impossible."

But now that the shuttle fleet has officially been retired, where do space robotics go from here? Well, they go much deeper into space, said Roberts.

Robotic probes will be sent to asteroids to pluck up material and send it back to scientists on Earth, for instance. Robotic rovers will continue to study the surface of Mars.

And if humans are sent to back to the moon or to Mars for the first time , robots are likely to proceed them, digging for water and setting up an outpost that will keep humans sheltered and safe in a harsh and unfamiliar environment.

"Human-robotic cooperation -- I think it's an area that NASA is studying," Roberts said. "We're looking at roles that robots play, roles that humans play when they're there together with robots, and the roles robots will have after humans leave."

It should be a time of great advancement in robotics. And it will be key to humans moving deeper into outer space, said Roberts.

Actually, the Obama administration's new plan for NASA is for commercial companies to focus on building what essentially will be space taxis, while space engineers focus on things like next-generation heavy-lift engines and robotics.

"There is a lot of work to do in [terms of] how do we [use robots to] maximize the humans' work," said Roberts. "What smarts do you put in a robot to have them work nicely with humans? How do humans and robots work side-by-side. How do they not hurt the humans if a sensor goes bad?"