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Due to its unique value the existing achievements of robot autonomous control cannot fully meet the requirements of harsh environment. Artificial control system which has full range of operational functions，real-time and good stability，will become the prerequisite for the task being smoothly and safely completed by the robots at the present stage. Based on the preliminary foundation about hardware system of the manned hexapod robot，the paper presents a control mode which is integrated with the principles of situational awareness and man-machine function allocation. Optimal allocation schemes through establishing a multi-objective fuzzy decision model is obtained. Finally a hexapod robot control system whose the core controller is B&R controllers is designed and achieve the real-time condition monitoring of robotic and the accuracy of motion control. at the same time the integration of the proposed human-machine function allocation algorithm and good maneuverability of the system is also verified. We provide manned hexapod robot control system as the reference in the future.

The experiment was conducted to explore the extraction effect of different extraction methods on red beet polysaccharide. In the experiment, red beet was used as raw material, water extraction and alcohol precipitation method and ultrasonic assisted water extraction method were used respectively. Orthogonal design was carried out to optimize the extraction process on the basis of single factor experiment, and the effect of liquid to solid ratio, extraction temperature and extraction time on the extraction rate of red beet polysaccharide were investigated. The crude polysaccharides were purified by Sevag reagent, activated carbon and petroleum ether. The results showed that the optimal extraction conditions of red beet polysaccharide by water extraction and alcohol precipitation were as follows: Liquid to solid ratio of 90 mL/g, extraction temperature of 70 °C, and an extraction time of 1.5 h. Under the conditions, the extraction yield of red beet polysaccharide was the highest, reaching 2.33%. The optimal extraction process of ultrasonic assisted water extraction was as follows: Liquid to solid ratio 40 mL/g, extraction temperature of 40 °C, extraction time of 30 min. Under the conditions, the extraction rate was 6.85%. The removal rates of protein, pigment and fat were 29.73%, 3.88% and 2.76%, respectively. The study indicates that ultrasonic assisted water extraction method is more suitable for the extraction of red beet polysaccharide with less solvent, shorter time, lower temperature and higher extraction rate. [ABSTRACT FROM AUTHOR]

In order to improve the flame retardancy of polyvinyl chloride (PVC) used for wires and cables, zinc borate (ZB) was added to PVC to prepare PVC composites, and its flame retardancy and mechanical properties were studied. The mechanical properties test showed that with the increase of ZB content, the tensile properties of PVC composites decrease dgradually. However, when the ZB content was less than 6%, the tensile properties of PVC composites decreased slightly, which still met the requirements of relevant standards. The flame retardant test showed that the flame retardant of PVC composites increased with the increase of ZB content. When the content of ZB was 6%, the comprehensive properties of PVC composite (4#) were excellent. Compared with the composite without ZB, the flame retardancy of the 4# sample was significantly improved, the oxygen index reached 40.1%, the vertical combustion grade reached FV-0, the smoke density decreased to 72, the HCl release decreased to 41 mg/g, the peak heat release rate (PHRR) was decrease by 19.9%, the total heat release (THR) was decreased by 36.5%, and the total smoke production (TSP600 s) was decreased by 69.7%. The tensile strength of the composite was decreased by 10.8%, and the elongation at break was decreased by 12.7%. [ABSTRACT FROM AUTHOR]

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