MOSCOW (AP) — A Russian space capsule carrying a humanoid robot has failed to dock as planned with the International Space Station.

A statement from the Russian space agency Roscosmos said the failure on Saturday was because of problems in the docking system. It said the space station itself and the six-person crew are safe.

Roscosmos head Dmitry Rogozin said on Twitter that a new docking attempt would be made on Tuesday.

The capsule was launched Thursday as part of tests of a new rocket that is expected to replace the Soyuz-FG next year.

It is carrying a robot called Fedor, which will perform two weeks of tests aboard the space station. Vladimir Solovyev, flight director for the Russian segment of the ISS, said the robot had not been taught how to manually conduct a docking.