Motion Simulation Services
STL’s six degree of freedom (6DOF) Motion Platform is a variant of the Stewart Table or Hexapod and is similar to those found in flight simulators.
It’s commercially available for hire. Please contact us here if you would like to know more.
- The Motion Platform top frame may be moved in a way that simulates the motion of the deck of a vessel at sea. Equipment intended for marine use may be mounted on the top frame of the platform in order to evaluate it’s performance when subjected to the pitch, roll, yaw, heave surge and sway motions normally experienced at sea.
- The top and bottom frames of the Motion Platform are mechanically connected by six ‘legs’. Each ‘leg’ consists of a hydraulic cylinder with an associated position sensor attached. The position sensors monitor the extension of the cylinder rods.
- Pressurised oil is supplied to the hydraulic cylinders via dedicated Digital Servo-proportional Directional Valves. In this way, the extension of the cylinders may be independently controlled.
The Motion Platform may be controlled using the following methods:
- Digital Hand Control (Open Loop). Digital position demands are provided by ‘extend/retract’ toggle switches mounted on a simple switch panel known as the ‘Digital Hand Controller’ (DHC). The directional valves are operated in an open loop ‘Jog’ mode.
- Analogue Hand Control (Closed Loop). Analogue position demands are provided by an Analogue Hand Controller (AHC). Control is further enhanced using position feedback derived from the position sensors mounted on each hydraulic cylinder. The directional valves are operated in a closed loop ‘Normal’ mode.
- Computer Control (Closed Loop). Analogue position demands are provided by a Digital-to-Analogue Converter (DAC) connected to a PC running STL’s Motion Platform Control software. The directional valves are operated in a closed loop mode.