In this paper, an electromagnetic actuator having four discrete positions is discussed. The principle, the modeling, and an experimental device of this actuator are presented in this study. This actuator is composed of a mobile permanent magnet, four fixed permanent magnets, which ensure the holding of the discrete positions, and two perpendicular wires to switch independently in two perpendicular directions. The mobile part has four discrete positions, two in each direction. An electromagnetic actuator modeling has been realized to compute the magnetic and electromagnetic forces exerted on the mobile magnet and its displacement. The experimental device was designed using this model and then manufactured. The stroke of the mobile part is 1 mm times 1 mm. The driving current ranges from 3 to 7 A. A comparison between experimental and modeled results is carried out. Good agreement on the displacement curves and on the rise times is observed for all the range of controlling currents.

In this paper, a digital actuators array composed of 25 elementary digital actuators placed in a 5 × 5 matrix configuration is presented. The originality of the elementary digital actuator lies in its ability to reach four discrete positions in a horizontal xy-plane. An analytical model of the array is presented and has been used to design an experimental prototype. A control module is proposed to independently or simultaneously control the elementary actuators along two displacement axes. This module is based on a control strategy and on a dedicated electrical control circuit which reduces the number of channels needed to control the array. The proposed control strategy is based on position and displacement matrices to characterize the desired motion of each elementary actuator. Experimental tests of the actuators array are presented in the paper to validate the control module. Finally, an application of the array as a xy-plane displacement device is shown.