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Tilt and vibration sensor and method for forming the sensor with a piezoresistive membrane having a weight affixed proximate its center for detecting the tilt and vibration of a body. The membrane may include four piezoresistors placed proximate the edges of the membrane at the points of maximum str

Tilt and vibration sensor and method for forming the sensor with a piezoresistive membrane having a weight affixed proximate its center for detecting the tilt and vibration of a body. The membrane may include four piezoresistors placed proximate the edges of the membrane at the points of maximum stress when the membrane is subject to a uniform applied pressure. The piezoresistors may form a Wheatstone bridge circuit to generate a first and second output voltage in response to changes in resistance of the piezoresistors under the uniform applied pressure. The first output voltage may be indicative of the angle of inclination of a body and the second output voltage may be indicative of the vibration of the body. The membrane may be fabricated from a silicon wafer using known photolithography and etching processes. The membrane may be connected with a voltage source and secured within an appropriate housing to be placed in an operational environment.

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Tilt and vibration sensor and method for forming the sensor with a piezoresistive membrane having a weight affixed proximate its center for detecting the tilt and vibration of a body. The membrane may include four piezoresistors placed proximate the edges of the membrane at the points of maximum str

Tilt and vibration sensor and method for forming the sensor with a piezoresistive membrane having a weight affixed proximate its center for detecting the tilt and vibration of a body. The membrane may include four piezoresistors placed proximate the edges of the membrane at the points of maximum stress when the membrane is subject to a uniform applied pressure. The piezoresistors may form a Wheatstone bridge circuit to generate a first and second output voltage in response to changes in resistance of the piezoresistors under the uniform applied pressure. The first output voltage may be indicative of the angle of inclination of a body and the second output voltage may be indicative of the vibration of the body. The membrane may be fabricated from a silicon wafer using known photolithography and etching processes. The membrane may be connected with a voltage source and secured within an appropriate housing to be placed in an operational environment. g the body in a contact-free manner; immersing the body in the fluid; independently directing electric power to the electric drive for rotating the body and for magnetically supporting the body, respectively; measuring the electric power consumed by the electric drive for rotating the body; and determining the viscosity of the fluid from the electric power consumed by the electric drive for rotating the body. 2. A method according to claim 1 wherein the rotatable body is adapted to induce a flow of the fluid and the electric power consumed by the electric drive is a combination of electric power consumed by the electric drive as a result of the viscosity of the fluid in which the body is immersed and electric power consumed by the electric drive for inducing the flow of the liquid. 3. A method according to claim 2 wherein the electric power consumed by the electric drive as a result of the viscosity of the liquid amounts to at least about 80% of the total electric power consumed by the electric drive. 4. A method according to claim 2 wherein the electric power consumed by the electric drive for overcoming the viscosity of the fluid is at least about 95% of the overall power consumed by the electric drive. 5. A method according to claim 1 wherein the electric drive includes a stator winding for rotating the body and wherein determining the viscosity of the fluid includes varying an electric current directed to the stator winding in accordance with a pre-settable scheme for determining the viscosity of the fluid. 6. A method according to claim 1 including varying a speed of rotation of the rotary drive in accordance with a pre-settable scheme for determining the viscosity of the fluid. 7. A method according to claim 1 wherein the electric drive includes a stator winding, and including regulating a temperature of the fluid in which the rotatable body is immersed by varying a heating current applied to the stator winding. 8. A method according to claim 1 including determining a density of the fluid. 9. A method according to claim 8 wherein at least one of the determining steps is performed as a function of at least one of a location within the fluid and time. 10. Apparatus for determining the viscosity of a fluid comprising a rotatable body for rotation when immersed in the fluid; an electric drive including a stator winding for rotating the body and magnetically rotatably journalling the body in a contact-free manner; a source of electric power for the electric drive for rotating the body; and a processor for determining the viscosity of the fluid from the electric power consumed by the electric drive for rotating the body when the body is immersed and rotates in the fluid. 11. Apparatus according to claim 10 wherein the body includes a fluid flow inducing member that rotates with the rotor and causes at least a portion of the fluid to flow. 12. Apparatus according to claim 11 wherein the body is configured so that at least 95% of the electric power consumed by the electric drive for rotating the body is consumed for overcoming rotational resistance encountered by the body as a result of the viscosity of the fluid. 13. Apparatus according to claim 10 wherein the body and the stator winding define a bearing-free electric motor. 14. Apparatus according to claim 10 including a housing surrounding the rotatable body and separating the body from the stator. 15. Apparatus according to claim 10 wherein the rotatable body has a diameter and a height extending in an axial direction, and wherein the diameter of the body is larger than the height of the body. 16. Apparatus according to claim 10 wherein the electric drive comprises a temple motor and the stator winding is defined by a plurality of L-shaped stator teeth each having first and second transverse limbs connected by a magnetic return yoke, the first stator limb extending parallel to an axis of rotation of the body and the second limb extending radially relative to the axis of rota