3. Gyroscopes with two degrees of freedom

3.1 Definition and structure

We call a two-degrees-of-freedom gyroscope or a free gyroscope a device with (figure 7 ):

• a housing B, always associated with a pick-off system defining the zero axis Z of the device, linked to B; by definition, Z is the direction of the spindle moulder axis Δ when the pick-off system signals are cancelled;

• a spinner suspension designed to constrain the spinner to rotate about a fixed point O linked to the housing (the spinner's center of rotation), while allowing it...