A brief overview of previously built Electro-Optical Tracking system reveals a trend toward smaller, more agile systems. Steel cable drive technology is an alternative to gearbox, belt and pulleys, chains and sprocket and other currently available transmission for several significant advantages, which includes backlash free, high stiffness, high efficiency, no lubrication etc.. As a new type of drive form, there were several key tradeoffs for the cable drive application, which will be developed and subjected in detail in this paper. Firstly Transmission principle and properties of cable drive is studied. Secondly, related design considerations of cable drive will be implemented and researched in detail, including the cable selection and capstan design, cable-groove matching strategy and cable tensioning design. Finally, actual application example of precise steel cable drive is presented for an Electro-Optical tracking gimbals, and performances tested validate the significant advantages of precise cable drive technology.

A novel method in the solution of the pointing problem for electro-optical pointing system (EOPS) is presented in this paper. Firstly, the error sources are analyzed in detail. And then, a linear model whose parameters have definitely physical meaning is developed to improve pointing accuracy. Extensive experiments have been carried out and the results show that the system errors can be eliminated by the model effectively and the pointing accuracy of the azimuth and elevation axes have been improved from 0.4541º and 0.2959º to 0.038º and 0.031º respectively.

Precise cable drive has been developed as an alternative transmission element to gearbox, belt and pulleys, chains and sprocket in Electro-Optical Tracking system. Precise cable drive has several significant advantages including backlash free, high stiffness, high efficiency, no lubrication etc. This paper develops analytical methods to predict the transverse oscillation frequency of precise cable drive to enable designers to better assess dynamic performance in the design study phase. Theoretical formulation of transverse oscillation equation for precise cable drive is carried out based on Hamiltons principle taking into account flexural rigidity of cable. Furthermore, the transverse oscillation frequency is obtained from the transverse oscillation equation assuming small and linear vibration. Parametric studies are conducted to evaluate the relationship between the oscillation properties and cable drive parameters.

Multistage open association (MSOA) and helical growth (HG) mechanisms describe the linear growth of supramolecular polymer chains and the helical growth of supramolecular chains with the intra-assemble cooperative effect, respectively. Both mechanisms were proposed by Ciferri. Assuming that supramolecular polymerization follows the step-growth and the interaction between repeat units is independent of molecular weight, the kinetics of MSOA and HG can be mathematically analyzed. In this paper the relationships among degree of polymerization (DP), unimer concentration (C0), and equilibrium constant (K) for MSOA and DP , concentration of helical polymer ( h C ), and nucleation factor (σ ) for HG were derived.

Butterfly pivot is a large-travel rotational flexure pivot, which can provide elastic support for the rotational shaft in several ten degrees. Because of the complex structure, stiffness calculation of butterfly pivot is always completed by the method of Finite Element Analysis (FEA), which is not suitable for parameter design and optimization. The serial structure of four-blade isosceles-trapezoid (FBIT)is proposed to simplified the complex structure of the butterfly pivot. The FBIT is analyzed and the theoretical formula of stiffness calculation for rotation stiffness is derived in detail based on the essential theory of Mechanics of Materials. Design and optimization of rotation stiffness for each element can be achieved easily with the obtained the theoretical formula of rotation stiffness. The total rotation stiffness of the whole butterfly pivot is calculated and the rotation stiffness comparison between using the theoretical method and by the method of FEA is performed. The error between the theoretical rotation stiffness and the result of the FEA is less than 10%. It is acceptable and without any influence on the validity of the work and concept presented in this paper.