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In order to accomplish exploration missions in complex environments, a new type of robot has been designed. By analyzing the characteristics of typical moving systems, a new mobile system which is named wheel-tracked moving system (WTMS) has been presented. Then by virtual prototype simulation, the new system’s ability to adapt complex environments has been verified. As the curve of centroid acceleration changes in large amplitude in this simulation, ride performance of this robot has been studied. Firstly, a simplified dynamic model has been established, and then by affecting factors analysis on ride performance, an optimization model for suspension parameters has been presented. Using NSGA-II method, a set of nondominated solutions for suspension parameters has been gotten, and by weighing the importance of the objective function, an optimal solution has been selected to be applied on suspension design. As the wheel-tracked exploration robot has been designed and manufactured, the property test has been conducted. By testing on physical prototype, the robot’s ability to surmount complex terrain has been verified. Design of the wheel-tracked robot will provide a stable platform for field exploration tasks, and in addition, the certain configuration and suspension parameters optimization method will provide reference to other robot designs.

In this study, the flavor characteristics and volatile compounds of cold-pressed flaxseed oil were analyzed using quantitative descriptive analysis, headspace solid phase microextraction and simultaneous distillation extraction coupled with gas chromatography-mass spectrometry-olfactometry (GC-MS-O) and chemometrics. The results showed that cold-pressed flaxseed oil had a unique flavor, mainly presenting fresh grassy and fishy flavors. Totally 34 characteristic volatile components were detected, including 12 aldehydes, 7 alcohols, 5 acids, 3 terpenes, 3 alkanes, 2 ketones and 2 aromatic compounds. Based on GC-O analysis, detection frequency (DF ≥ 6) and odor activity value (OAV ≥ 1), 2-ethyl hexanol, hexanol, (E)-2-hexenal, hexanal, and (E,E)-2,4-heptadienal were found to be the major contributors to the grassy flavor, and (Z)-4-heptenal the major contributor to fishy flavor. Principal component analysis (PCA) validated the correlation between the characteristic flavor intensity and the sensory flavor attributes of cold-pressed flaxseed oil from different regions. The results of this study can provide a theoretical basis for improving the aroma, processing and quality of cold-pressed flaxseed oil.

Hot deformation characteristic of Ti-5Al-5V-5Mo-3Cr alloy with a starting microstructure of an equiaxed single β microstructure is examined in relation to microstructural evolution and the result according to processing map technique. In testing at 700°C, subgrain formation is dominant at higher strain rate, while superplasticity occurs at lower strain rate. Herein, dynamic α precipitation from supersaturated β phase occurs during deformation and affects the flow behavior. In testing at and above 800°C, dynamic recovery (DRV) is dominant and continuous dynamic recrystallization (CDRX) also occurs especially in the vicinity of boundaries of prior-β-grains. There are three domains having an optimized power dissipation efficiency (ranging from 40% to 50%) in processing map. These three domains are reasonably explained in relation to microstructural conversion of frequent activations of grain boundary sliding, dynamic recovery and simultaneous occurrence of dynamic recovery and continuous dynamic recrystallization. [ABSTRACT FROM AUTHOR]