A Stewart platform is a type of parallel manipulator that has six prismatic actuators enabling 6-DOF, commonly hydraulic jacks or electric linear actuators, attached in pairs to three positions on the platform's baseplate, crossing over to three mounting points on a top plate.

All 12 connections are made via universal joints.

Devices placed on the top plate can be moved in the six degrees of freedom in which it is possible for a freely-suspended body to move:

three linear movements x, y, z (lateral, longitudinal, and vertical) and the three rotations (pitch, roll, and yaw).
The Stewart platform design is extensively used in motion simulators such as in the full flight simulator which requires all 6 degrees of freedom.

FUM-Stewart is another developed robot in the class of Stewart robots. It has a 450 kg payload capacity with electromechanical linear actuators for high speed and high acceleration applications.
FUM-Stewart is able to move its load in the x, y, z directions and rotate around their axes.