Precision tripod motion system with six degrees of freedom

A tripod motion system comprising:

• a bottom plate including three hinges;
• a top plate including three joints, wherein the top plate is configured to receive a workpiece;
• a plurality of linear actuators, wherein each linear actuator is coupled to an associated one of the three hinges of the bottom plate and coupled to an associated one of the
• three joints of the top plate;
• and
• a rotator component configured to rotate the top plate by rotating about a Z-axis of the tripod motion system, wherein the plurality of linear actuators and the rotator components are configured to, in response to being displaced by an external force, return the top plate to a predetermined set position with sub-micron positioning accuracy;
• wherein at least one linear actuator of the plurality of linear actuators comprises:
• a positioning actuator, configured to, in response to the top plate being displaced by the external force, provide an extension force to return the top plate to the predetermined set position with sub-micron positioning accuracy;
• and
• one or more displacing actuators configured to provide an actuation force that adds to the extension force to hold the at least one linear actuator at the predetermined set position, wherein the actuation force is a majority of a displacement force generated by the at least one linear actuator.

A method of operating a tripod motion system with six degrees of freedom, the method comprising:

• in the tripod motion system, changing a length of at least one linear actuator of three linear actuators over a linear actuation span, wherein each linear actuator of the three linear actuators is coupled to an associated one of three hinges of a bottom plate and coupled to an associated one of three joints of a top plate, wherein the top plate is configured to receive a workpiece;
• and
• in the tripod motion system, in response to the top plate being displaced by an external force, returning the top plate to a predetermined set position with sub-micron positioning accuracy by providing an extension force and moving a ball coupled to an associated one of the three joints to a predetermined extension position;
• wherein each linear actuator of the three linear actuators comprises:
• a positioning actuator, configured to, in response to the top plate being displaced by the external force, provide the extension force to return the top plate to the predetermined set position with sub-micron positioning accuracy and move the ball to the predetermined extension position;
• and
• one or more displacing actuators configured to provide an actuation force that adds to the extension force to hold the at least one linear actuator at the predetermined set position, wherein the actuation force is a majority of a displacement force generated by the at least one linear actuator.