Two dimensional inductive encoder for measuring 2D displacement

Two dimensional measurements are usually performed by two one dimensional encoders. In this paper, the simple method is proposed, which can directly measure the displacements in two dimensions. The measurement is based on inductive method where a flat coil moves adjacent to another one and the induced voltage give the relative position. In this research there are three flat coils with special patterns. One for stationary surface and two for moving surface are designed. When these surfaces move adjacent to each other, one of the moving coils gives the displacement in X direction and the other one gives the displacement in Y direction. The pattern of coils are designed in a way that there is no interference between X and Y data. Experimental results show the effectiveness of the concept.