Small scanning mirror mechanism

The CSEM has developed an optomechanical linear scanner. This scanner has a limited displacement range, performed with high resolution. The resolution is obtained through a very high precision motion guiding of the scanner itself. This paper describes the main features of the scanner system as well as its control system. After a complete description of the system, a state space model derived from the mechanical and electrical equations of the system is introduced. This model will be used for the design of a state space controller based on a pole placement algorithm, to make the system behave as a fourth order Bessel filter. To better track the desired reference trajectory, a feedforward will be added to the controller as well as a disturbance observer. Moreover, at each startup, an auto identification followed by a controller re-calculation is performed.