Doraemon: Nobita's History of Space Development

Roburu had an accident while transcending time and space, and the door of the spacecraft was connected to the tatami in Nobita's room. From then on, Wilderness Star became Nobita's second playground. Nobita and the Roburus had a great time. But the Kaltai Mining Company continues to threaten the safety of the planet's inhabitants in order to obtain mineral deposits. Finally, with the help of Nobita and his partners, the conspiracy of Kaltai Mining Company was shattered, and the super light exit was restored to its original state, and Nobita returned to Earth.