a platform is mounted by bellows , at least one for each degree of freedom of the platform . the bellows may provide either an active or a passive mounting for the platform . by arranging a suitable number of such bellows in supporting relationship a platform or floater for example six degrees freedom can be provided . using pneumatic bellows in opposed pairs , one pair for each degree of freedom and by controlling the pressure in the bellows selected forces may be applied to the platform to accurately position the platform or to provide feedback for a sensory control e . g . as reflected force applied to the joystick . the position and orientation of the platform , i . e . movement of the platform , may be used to generate signals for example as in a joystick . sensing the pressure in each of the bellows of each of the pairs permits the forces being applied by or to the platform to be monitored .