Rotational rate sensor

A sensing device for measuring angular rates about an axis, said device comprising:

• a housing defining a fluid cavity, said housing comprising at least one excitation electrode, at least two output electrodes, and at least two ground electrodes;
• an electrolytic fluid essentially filling said cavity;
• and
• a measuring circuit wherein said output electrodes are connected to at least one differential amplifier and said differential amplifier is connected to a synchronous demodulator.

A rotational rate sensor comprising:

• a housing defining a fluid cavity;
• at least one excitation electrode disposed within said housing and
• at least one output electrode disposed within said housing;
• at least one ground electrode disposed within said housing;
• and
• an electrolytic fluid sufficiently filling said fluid cavity so that all of said electrodes remain in contact with said fluid during less than about a 330 degree rotation of said housing.

A method for sensing the rotational rate of an object about an axis, said method comprising:

• mounting a rotational sensor to an object having at least one axis of rotation, said sensor comprising at least one excitation electrode, at least one output electrode, at least one ground electrode and an electrolytic fluid sufficiently filled in a fluid cavity to allow all of said electrodes to remain in contact with said fluid during less than about a 330 degree rotation of a housing containing said cavity;
• allowing rotational movement of said object about said axis;
• allowing movement of ions contained in said electrolytic fluid within said cavity in response to said rotational movement of said object;
• and
• measuring said movement of ions from said excitation electrode toward at least one of said output electrodes to create a signal representing at least some degree of rotation of said object.