Lithographic apparatus, positioning system for use in a lithographic apparatus and method

A positioning system for use in a lithographic apparatus having a reference body, the positioning system comprising:

• a main body;
• a reaction body;
• an actuator;
• and
• a controller;
• wherein the main body is moveable relative to the reference body along a path in a first direction and a second direction, wherein the first direction is opposite to the second direction,
• wherein the reaction body is moveable relative to the main body along a further path in the first direction and the second direction,
• wherein the reaction body is moveably connectable to the reference body so as to be moveable relative to the reference body in the first direction and the second direction,
• wherein the controller is arranged to provide a first signal and a second signal to the actuator,
• wherein the actuator is arranged between the main body and the reaction body so as to accelerate the main body in the first direction and to accelerate the reaction body in the second direction under control of the first signal, and
• so as to accelerate the main body in the second direction and to accelerate the reaction body in the first direction under control of the second signal,
• wherein the controller is arranged to determine when the reaction body moves in the second direction, and
• wherein the controller is arranged to provide the second signal after the first signal to the actuator when the reaction body moves in the second direction along the further path.

A method for limiting a magnitude of an excursion of a reaction body in a lithographic apparatus, wherein the lithographic apparatus comprises a reference body, a main body and a reaction body,

• wherein the main body is moveable relative to the reference body along a path in a first direction and a second direction, wherein the first direction is opposite to the second direction,
• wherein the reaction body is moveable relative to the main body along a further path in the first direction and the second direction,
• wherein the reaction body is moveably connected to the reference body so as to be moveable relative to the reference body in the first and second direction, the method comprising:
• accelerating the main body in the first direction and accelerating the reaction body in the second direction under control of a first signal;
• accelerating the main body in the second direction and the reaction body in the first direction under control of a second signal;
• providing the second signal after providing the first signal when the reaction body moves in the second direction along the further path.