Two axis capacitive inclination sensor

A capacitive sensing arrangement comprising:

• a sensor housing;
• first capacitive detecting means disposed within said sensor housing for providing a first capacitance C3 and for changing said first capacitance to (C3+any change in C3) in response to a particular change in the angular orientation of said sensor housing with respect to a certain axis;
• second capacitive detecting means disposed within said sensor housing for providing a second capacitance C4 and for changing said second capacitance to substantially (C3-any change in C4) in response to said particular change in angular orientation of said sensor housing with respect to said certain axis;
• oscillator means for generating a periodically alternating electrical signal;
• and
• switching means connected to said first and second detecting means for alternately coupling said first detecting means and said second detecting means to said oscillator means said switching means including:
• state control means connected to receive said periodically alternating electrical signal for decoupling said first electrode from said oscillator means and for coupling said second electrode to said oscillator means in response to a level transition of said periodically alternating signal.

A roll and pitch axes capacitive sensing arrangement comprising:

• a spherically shaped outer member having an inner concave common electrode surface;
• an inner member disposed within said outer member, said inner member having an outer convex insulating surface and an inner concave electrically conductive surface, said inner concave electrically conductive surface being divided into first, second, third and fourth detecting electrodes;
• means for locating said inner member with respect to said outer member so that a cavity is defined between said inner member outer convex surface and said outer member inner concave surface;
• a quantity of dielectric fluid contained within said cavity, said quantity of dielectric fluid between any one of said detecting electrodes and said common electrode surface varying depending upon the roll and pitch orientation of said sensory, said first and third detecting electrodes are responsive to movement in a roll direction and said second and fourth detecting electrodes responsive to movement in a pitch direction;
• first oscillator means for generating a periodically alternating electrically signal;
• and
• first switching means connected to said first and third detecting electrodes for alternately coupling said first detecting electrode and said third detecting electrode to said oscillator means, said first switching means includes state control means connected to receive said periodically alternating electrical signal for decoupling said first electrode from said oscillator means and for decoupling said third electrode to said oscillator means in response to a level transition of said periodically alternating signal;
• second oscillator means for generating a periodically alternating electrical signal;
• and
• second switching means connected to said second and fourth detecting electrodes for alternately coupling said second detecting electrode and said fourth detecting electrode to said oscillator means, said second switching means includes state control means connected to receive said periodically alternating electrical signal for decoupling said second electrode from said oscillator means and for coupling said fourth electrode to said oscillator means in response to a level transition of said periodically alternately signal.