摘要:
An inertial reference system for a spacecraft includes an attitude control assembly and a plurality of force sensors. The attitude control assembly is coupled to a spacecraft body at a plurality of attachment points and at least one of the plurality of force sensors is integrated at each of the attachment points. In one embodiment, the force sensors are piezoelectric transducers. In another embodiment, the control assembly is coupled to the spacecraft body at four attachment points. In yet another embodiment, each of the force sensors is preloaded by a bolt that attaches the attitude control assembly to the spacecraft body.
摘要:
A reaction wheel system is provided that includes at least two rotors. The first rotor is the primary rotor that provides the large output torques to the vehicle. The second rotor is a vernier control rotor. The primary rotor and vernier control rotor each rotate about a common axis. The vernier control rotor has an inertial mass that is less than the inertial mass of the primary rotor, and rotates independently of the primary rotor. Because the vernier control rotor can be rotated independently from the primary rotor, it can be used to significantly improve the performance of the reaction wheel system. Specifically, the vernier control rotor is used to provide relatively small output torques. These relatively small output torques can be used to reduce the disturbances created by motor ripple, provide precise torque output control and/or reduce the disturbances created by static friction.
摘要:
A spacecraft payload, suspended by an isolator, is locked down during launch by using a compliant member to pull on a pin, clamping the payload against the launch lock. The payload is unlocked, after launch, by heating a shape memory alloy to move the pin to overcome the compliant member, releasing the payload from launch lock. The payload may be re-locked for reentry by heating another shape memory alloy to push the pin against the other shaped memory alloy.
摘要:
A gear drive having a third order damper operating with the antibacklash gear so as to lower the impact of the antibacklash gear at high torques to reduce gear wear while maintaining good contact with the antibacklash gear at lower torques to maintain high accuracy and bandwidth.
摘要:
A connector tow for providing external electrical access to an electrical device embedded within a composite structure. The connector comprises a plurality of tubes disposed between a pair of opposed film layers. The film layers are adhered to opposite sides of the plurality of tubes and can be comprised of an insulating material so as to electrically isolate the plurality of tubes. By extending through the edge surface of the composite structure, the electrical ports can be accessed during the fabrication of the a composite structure such that the operations of the embedded electrical device can be monitored.
摘要:
A composite structure and related fabrication method is provided which has a plurality of composite material layers and at least one embedded shape memory alloy component for providing controlled structural deformation. The shape memory alloy component includes a shape memory alloy tendon having a relaxed shape at temperatures below a predetermined transition temperature and a contracted shape at temperatures above the predetermined transition temperature. The shape memory alloy component also comprises a pair of electrically insulating opposing face sheets adhered to opposite sides of the shape memory alloy tendon to electrically isolate the shape memory alloy tendon from the surrounding composite material layers. The shape memory alloy component is embedded within the plurality of composite material layers such that raising the temperature of the shape memory alloy tendon above the transition temperature creates a controlled structural deformation of both the shape memory alloy component and the surrounding composite material layers.
摘要:
A composite structure and related fabrication method is provided which has a plurality of composite material layers and at least one embedded shape memory alloy component for providing controlled structural deformation. The shape memory alloy component includes a shape memory alloy tendon having a relaxed shape at temperatures below a predetermined transition temperature and a contracted shape at temperatures above the predetermined transition temperature. The shape memory alloy component also comprises a pair of electrically insulating opposing face sheets adhered to opposite sides of the shape memory alloy tendon to electrically isolate the shape memory alloy tendon from the surrounding composite material layers. The shape memory alloy component is embedded within the plurality of composite material layers such that raising the temperature of the shape memory alloy tendon above the transition temperature creates a controlled structural deformation of both the shape memory alloy component and the surrounding composite material layers.
摘要:
The present invention relates to a reaction wheel assembly and fiber optic gyro device. The device includes a reaction wheel assembly having a reaction wheel assembly housing, a fiber optic gyro coil integrated with the reaction wheel assembly housing, and a fiber optic gyro electronics integrated with the reaction wheel assembly housing. The fiber optic gyro coil may be wound around the reaction wheel assembly housing. The gyro coil may also be located within the reaction wheel assembly housing.
摘要:
A remote Information Management Network routing system located either at an independent hosting facility or at a central station monitoring facility that receives event and alert information from a security or premise monitoring system and sequentially transmits interactive notifications about the event and alert information to wired and wireless devices specified in a user profile within the Information Management Network.
摘要:
A method is provided for fabricating a composite structure having an externally accessible electrical device embedded therein. At least one supporting ply is initially provided that has first and second depressions. An electrical device having at least one electrical lead is disposed in the first depression and a connector tow having at least one tube with opposed first and second ends is disposed in the second depression. The first end of the tube of the connector tow is electrically connected to the electrical lead. Thereafter, at least one additional ply is stacked on the supporting ply such that the electrical device and the connector tow are embedded. The stacked plies can then be consolidated to form an integral laminate structure. Following the consolidation, the second end of the tube of the connector tow can be accessed through the edge surface of the laminate structure to thereby define an externally accessible electrical port for receiving a corresponding connector. As such, electrical contact can be established with the embedded electrical device via the tube and the electrical lead. By establishing electrical contact with the electrical device during the fabrication process, the operation and therefore the health of the embedded electrical device can thereafter be monitored.