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Abstract. Motor-driven flexible manipulator systems (MDFMSs) are widely used in industry robot fields. During the dynamic modeling, the separate investigation method which neglects the dynamic behavior of the driving motor will cause an error in the dynamic analysis of the flexible manipulator, especially with high-speed operations. This paper proposes a coupled dynamic model of the MDFMS in which the driving motor and flexible manipulator are considered as an integrated system, which can clearly reflect the influence of the dynamic effect of the driving motor. Based on the proposed dynamic model, the vibration responses of the flexible manipulator under different velocities, accelerations and structure parameters, as well as the effect mechanism of the driving motor on the vibration responses, are investigated. The results obtained in this paper contribute to the structure design, motion optimization and dynamic analysis of flexible manipulators.

This study assesses the displacement of coalbed methane by CO 2 migration along a fault into the coal seam in the Yaojie coalfield. Coal and gas samples were collected continuously at various distances in NO.2 coal seam from F19 fault. Vitrinite reflectance, maceral, and pore distributions and proximate analysis of fourteen coal samples were performed. Gas components, concentrations, carbon isotopes of 28 gas samples were determined. We examined the coal-gas trace characteristics of coalbed methane displaced away from the fault by CO 2 injection after geological ages. From east to west, away from the F19 fault, the CO 2 concentration decreased, whereas the CH 4 concentration increased gradually. The d 13 C values for CO 2 varied between À9.94& and 1.12&, suggesting a metamorphic origin. A wider range of d 13 C CO2 values (from À9.94& to 20&) was associated with the mixing of microbial carbon dioxide, isotopic fractionation during CO 2 migration through the microporous structures of coals, and/or carbon isotope fractionation during gas-water exchange and dissolution of CO 2 . Away from the F19 fault, the volumes of micropores, mesopores and macropores decrease gradually. The Dubinin-Radushkevich (DR) micropore volume decreased from 0.0059 to 0.0037 cm 3 g -1 , and the mesopore and macropore volumes decreased from 0.066 to 0.026 cm 3 g -1 . The CO 2 injection can mobilize aromatic hydrocarbons and mineral matter from coal matrix, resulting in the decrease in the absorption peak intensity for coal samples after supercritical CO 2 treatment, which indicates that chemical reactions occur between coal and CO 2 , not only physical adsorption.

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