MEMS Gyroscopes use the Coriolis force to measure angular movement. When a mass moves in a particular direction with a velocity v and an external angular rate is applied (red arrow), the Coriolis effect generates a force, shown here with the yellow arrow, that causes a perpendicular displacement of the mass. The value of this displacement is directly related to the angular rate. This displacement is read by measuring variations in capacitance, a robust and reliable technique successfully used across ST’s MEMS product lines.