Two tiny Japanese rovers have already begun to study the surface of a large asteroid Ryugu, but they do not move in the usual sense for us. The MINERVA-II1A and MINERVA-II1B landed on the surface on September 21 after descending from the mother spacecraft Hayabus-2, which arrived at the 900-meter asteroid Ryug.
Robots do not have wheels, as on the Martian rovers Opportunity and Curiosity. And there is a reason for this. The fact is that gravity on an asteroid is incredibly weak, so movement at the expense of wheels or tracks would push the device up at the slightest movement.
The artistic vision of the Japanese robots MINERVA-II1A and MINERVA-II1B on the surface of the asteroid Ryugu. Small robots move by jumping
Therefore, robots, with a size of 18 x 7 cm and a weight of 1.1 kg, bounce instead. To do this, use the torque, based on a disk-shaped rotating platform. The mechanism is designed to precisely control the amount of torque. This allows you to change the speed of the jump, so as not to exceed the speed of departure from the asteroid surface. Scientists added that the MINERVA-II1 rovers control the direction of the jumps by manipulating the orientation of the turntable. These jumps can cover 15 minutes and cover 15 meters of horizontal distance. Moreover, they are programmed for independent research without the need for control from the Earth.
A close look at the MINERVA-II1 rovers, delivered by the Hayabusa-2 spacecraft to Ryugu asteroid in September 2018. Rover 1A is on the left and 1B is on the right.
Such a mobility system was not invented specifically for the Hayabus mission2. It was originally built into the original MINERVA robot, which set off in the first mission of 2005 to the Itokawa asteroid. However, the device failed to land successfully.
If everything goes according to plan, the Hayabusa-2 will launch another MINERVA-II2 rover to the surface, as well as the MASCOT landing gear (10 kg). The latter contains four scientific instruments and should sit on Ryugu on October 3. It will move on the principle of the rest of the Japanese rovers.
The picture was taken by the Minerva-II1A rover during a jump after successfully landing on the surface of the asteroid Ryugu on September 21, 2018
The MASCOT system includes a tungsten pivot arm that is accelerated and slowed down by the engine, causing the entire system to swing. Therefore, the device is also able to move by jumping and maneuvering the location for conducting experiments. MASCOT will be able to move 70 meters between points. MINERVA-II2 seems interesting too. This is a complex small mechanism that combines four mobility systems in its 1 kg of weight. He is considered an optional rover in a mission, so it’s unclear exactly when he will be lowered to the surface. ml
The Hayabusa-2 mission cost $ 150 million and started in December 2014. Its main goals are to shed light on the early history of the solar system and the role that carbon-rich asteroids could play in the dawn of earthly life. In addition, the mission will try to return a sample of the ancient material of the asteroid to Earth. If all goes well, the capsule will land on a parachute in Australia in December 2020.
Recall that NASA also has a planned asteroid mission. The OSIRIS-REx probe must arrive in Bennu’s carbon asteroid orbit on December 31 and deliver the samples to Earth in September 2023.