摘要:
A system for isolating a supported structure from transmitting vibrations to a supporting base (10) in a spacecraft provides six degrees of freedom in a kinematic mounting. Six isolator elements (14) in a symmetric arrangement of three skewed isolator pairs provides viscous damping and vibration and shock attenuation during launch and operation in space. The isolators (14) employ two degrees of freedom flexure joints (20) at each mounting point to assure primarily axial deflection and minimize bending moments, and have tuning springs to optimize performance. The system permits deterministic design and allows calculation of all loads from the nominal geometry and the isolator axial stiffness. Limit stops (26) are provided between the supporting structure and the supported structure to limit excursions of the isolator members.
摘要:
An adjustable damper and isolation apparatus includes a damper housing (14) having a channel (18) coaxially positioned about an axis therethrough from a first end of the damper housing to a second end of the damper housing. A first compliant fluid chamber (19) is formed at the first end of the damper housing and a second compliant fluid chamber (21) is formed at the second end of the damper housing (14). A moveable damping adjustment member (16) positioned coaxially within the channel (18) forms a damping path (18) between the moveable damping adjustment member and the damper housing to connect the first and second compliant fluid chambers (19, 21). The position of the moveable damping adjustment member is adjusted within the channel to provide desired resistance to fluid flow through the damping path.
摘要:
A vibration isolation apparatus includes a shaft (16) having a first and second end (18, 20). A piston (30) having an axial bore is coaxially positioned with the shaft to provide a damping passage (32) between the piston and the shaft. A flange (34) extends radially from the piston for coupling the apparatus to a load. A first extension (22) is coupled to and extends radially from the first end of the shaft and a second extension (24) is coupled to and extends radially from the second end of the shaft. Primary bellows (50, 52) extending from and secondary fluid paths (26, 28) extending through the first and second extensions (22, 24) provide a first volumetric stiffness in series with the damper. Secondary bellows (42, 44) connect the flange (34) to the first and second extensions (22, 24) and are coaxial with the shaft to provide a second volumetric stiffness parallel with the damper and the first volumetric stiffness.
摘要:
An apparatus for generating phase modulator angular positional signals in digital form comprises a phase tracking loop receiving a phase modulated signal from the rotor (16) of a resolver (10) whose stator windings (12, 14) are excited in quadrature. The phase output of the resolver is proportional to the angular displacement (Φ) of the rotor. Signals (32, 44) for exciting the stator windings of the resolver are applied in phase quadrature to a phase detector (24) to develop an analog error signal (58) when combined with the rotor output signal (22). The analog phase error signal (58) provides an output indicative of the angular displacement of the rotor. The error signal is applied to a voltage controlled oscillator (64), converted (in 28) to digital form, and combined with the excitation signals in a closed loop to force the error signal to a null, whereupon the indicated digital output angle (at 26) is to coincide with the angular displacement of the rotor shaft.