The cutting-edge models can lumber around a room without falling over. A few can play the trumpet or serve tea. The truly sophisticated ones can just about manage the washing-up.

But by 2020, Japan predicts, humanoid robots will be ready to colonise the Moon. Other metallic brethren of these mechanical pioneers, said scientists in Tokyo, will be engaged in the bigger, more prosaic mission of cleaning Earth’s orbit of junk.

The first draft of the ambitious plan emerged yesterday from a Japanese task force on space and lunar exploration – a team of experts from various fields answering directly to Taro Aso, the country’s cartoon-loving Prime Minister, and charged with beefing up Japan’s space programme.

The group’s remit was to draft a five-year plan on the development and exploitation of space – a programme for action that was initially to have included the goal of putting a human Japanese astronaut on the Moon within the next 20 years. In the latest plans, though, robots have inherited the prime position in Japan’s first – and still unconstructed – lunar lander.Experts have been arguing for years that the country’s aim should be to develop humanoid robots to the point where they are capable of everything people can do, and more.

For fans of Japanese manga comics it also makes perfect sense: space colonisation by robots is depicted in dozens of titles every week. And yet Japan’s leading robotics experts are painfully aware of how immature the science really is. The Honda engineer Masato Hirose endured 20 years of frustration before making the Asimo robot walk upright on two legs.

Tomomasa Sato, the head of Tokyo University’s faculty of mechano-informatics and the current chairman of the Japan Robotics Association, was equally realistic about how far robots can go with current technology.

“The next stage is to be able to tell a robot to go and fetch something from somewhere in the house and bring it back without breaking it,” he said. “It is at the limit of our science.”

The panel will continue to work on the proposals until later this month, with the final recommendations likely to be formalised next month. The eye-catching plans to land robots on the Moon, though, are likely to be joined by a series of more pragmatic proposals relating to the use of space for defence. The panel has already mooted building a space-based sensor system to detect the launch of a ballistic missile, and has suggested that satellites be used to help to track natural disasters in Asia.

Japan’s renewed fascination with space has generated a rich flow of ideas. The Japan Aerospace Exploration Agency said recently that it was working on a satellite-based robot that could start work on cleaning up some of the 10,000 pieces of man-made space debris circling in orbit and threatening the wellbeing of passing satellites. The proposed robot janitor would extend conductive cable several kilometres in length into the void and fish it back for burning.