43results about How to "Avoid design complexity" patented technology

A mechanical independent blade control (MIBC) mechanism for controlling the pitch of each of the blades of a rotor blade system or a main rotor of a rotor aircraft independently of the other blades includes a plurality of actuators disposed in the fuselage below the hub of the rotor, each being operable to selectively control the pitch of an associated one of the blades independently of the other blades, and a plurality of mechanical linkages disposed within the annulus of the rotor mast, each coupled between a blade and an actuator and operable to transmit a force output by the actuator to a pitch horn fixed to an inner end of the associated blade. The mechanism enables the direction of pitch of each blade to be changed more than twice during one revolution of the rotor.

A decoding system for eight-to-fourteen modulation or eight-to-sixteen modulation (EFM / ESM), which has an analog to digital converter (ADC), an adaptive equalizer and a Viterbi decoder. The ADC receives an analog signal with an EFM or ESM feature, and converts the analog signal into a digital signal with the EFM or ESM feature. The adaptive equalizer converts the EFM or ESM digital signal into a first signal with a minimum phase feature. The Viterbi decoder receives the first signal and generates a decoding signal in accordance with a Viterbi algorithm and a channel model, and the Viterbi decoder discards nonexistent paths in accordance with the EFM or ESM feature when computing branch metric of a branch or a node.

The invention discloses a method for transmitting a complex message, which comprises the following steps: dynamically allocating memory for a three-dimensional message to be transmitted in a buffer area; and after a data pointer in the three-dimensional message is converted into deviation in the buffer area of the three-dimensional message, transmitting the three-dimensional message. The method not only can realize the transmission of the three-dimensional message, but also has simple message expression, thereby solving a series of problems resulted from heterogeneous structures of the message expression.

The invention relates to a damping method for forced vibration of an inertially stabilized platform. Electric connection is added between a vibration absorber and the inertially stabilized platform by introducing an active feedback link consisting of an angle sensor, an amplifier and a torquer to a passive vibration absorber, therefore, the added active feedback link increases comprehensive rotary inertia of an active part and a passive part of the vibration absorber in an electric manner; when external disturbance acts on the inertially stabilized platform, and under the condition that a control system does not participate in working, the passive part of the vibration absorber and the active feedback link generate the torque for resisting disturbance action simultaneously, so as to damp angle vibration of the inertially stabilized platform caused by external disturbance. By optimization of parameters of the vibration absorber, and under the condition that the specification of the passive vibration absorber is smaller, the purposes of improving the dynamic characteristic of the inertially stabilized platform, expanding damping the bandwidth of vibration of the system and reducing the steady-state error of the system are achieved. The damping method has the characteristics of independence, flexibility, simplicity and convenience and is applicable to an inertial system and a gyro device.

A novel quadrifilar helical antenna comprises a double-frequency helical tape (1), a balun structure (2), a helical supporting medium (3), a cable (4) and an amplitude-and-phase output circuit (5). The novel quadrifilar helical antenna is used for settling a problem of realizing unchanged antenna polarization in wave beam pointing reversing, wherein unchanged antenna polarization cannot be realized by an existing satellite communication terminal antenna. Furthermore the quadrifilar helical antenna can realize continuous receiving and transmission of the same communication signal. The quadrifilar helical antenna can satisfy a requirement for man-machine combination of the satellite communication terminal. The quadrifilar helical antenna settles a problem of no broad wave beam switching capability in a satellite communication terminal environment and furthermore can satisfy a requirement for multi-mode operation capability of the antenna by a system. Furthermore the novel quadrifilar helical antenna has advantages of high reliability and wide application range.