Abstract: A method for testing the hermetic seal of a packaged device, which includes: a package that delimits a device chamber; and a transducer device, which is arranged within the device chamber and generates an electrical signal indicating at least one physical quantity external to the package. The testing method includes the steps of: imposing a reference pressure in the device chamber; arranging the packaged device in a testing chamber in which a testing pressure is present, different from the reference pressure; and subsequently detecting possible pressure variations within the device chamber.

Abstract: An artificial gravity system and method for a spacecraft including a least one pair of rotatable stages wherein each stage is capable of rotating about at least one structural support in the spacecraft and wherein the rotatable stages in each pair of rotatable stages counter-rotate one another wherein each stage is capable of accommodating a plurality of occupants. The stages may be circular and deployable. The system may also include dynamic balance equipment in each stage consisting of a fluid redistribution design utilizing fluid pumping systems, storage- and reserve-volume tank pairs to redistribute fluid throughout each stage for optimal mass balance, stage- and spacecraft-mounted laser-tracking equipment for redundant speed measurement, drive assembly and a brake motor and wheel assembly, foldable structural support arms capable of reducing the radial space of each stage during takeoff, and an inertial measurement unit capable of detecting overall vehicle rotational rates.

Abstract: The angular velocity sensor includes a container, a sensing element in the container and a viscous fluid between the container and the sensing element. The sensing element is supported by the viscous fluid such as an ER fluid or an MR fluid. The angular velocity sensor detects acceleration of the body in which the angular velocity sensor is installed. The angular velocity sensor controls the viscosity of the viscous fluid depending on the acceleration of a body, by changing a voltage applied to the viscous fluid.

Abstract: A computer input device includes a magnetized fluid and an inertial body within the magnetized fluid. A signal converter provides angular acceleration information based on behavior of the inertial body. The computer input device can be attached to a Virtual Reality Suit, or can be used to control computer-generated graphical objects. The inertial body can be non-magnetic. The body can be solid or hollow. Electromagnets and/or permanent magnets can be used for magnetizing the fluid. Magnetic coils sense the changes in the magnetic flux lines. Signals from the magnetic coils are used by the signal converter to calculate the angular acceleration. A housing encloses the magnetized fluid and the inertial body.

Abstract: A sensor includes a housing and a magnetic fluid within the housing that incompletely fills the housing. An inertial body is in contact with the magnetic fluid. Displacement of the inertial body relative to the magnetic fluid is indicative of acceleration on the housing. The acceleration includes linear and/or angular acceleration. The inertial body can be an air bubble, or a dissimilar liquid. A plurality of magnets are mounted on the housing, wherein the magnetic fluid is positioned in droplets between the magnets and the inertial body. The magnetic fluid can be a single droplet between each magnet and the inertial body, or multiple droplets between each magnet and the inertial body. The remaining volume in the housing can be filled with a non-magnetic fluid.

Abstract: A micro-electromechanical system (MEMS) is described for economical sensing of angular accelerations, especially for use in biomechanical applications. The device design is inspired by that of the semi-circular canals of the inner ear, utilizing a fluid filled channel and differential pressure transducer. Using modem fabrication techniques, very sensitive angular acceleration instruments may be realized. By combining these fast response sensors with other sensors, such as DC response linear accelerometers, allows broader frequencies of human motion to be monitored.