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When humanoid robots work in human environments, they are prone to falling. However, when there are objects around that can be utilized, humanoid robots can leverage them to achieve balance. To address this issue, this paper established the state equation of a robot using a variable height-inverted pendulum model and implemented online trajectory optimization using model predictive control. For the arms' optimal joint angles during movement, this paper took the distributed polygon method to calculate the arm postures. To ensure that the robot reached the target position smoothly and rapidly during its motion, this paper adopts a whole-body motion control approach, establishing a cost function for multi-objective constraints on the robot's movement. These constraints include whole-body dynamics, center of mass constraints, arm's end effector constraints, friction constraints, and center of pressure constraints. In the simulation, four sets of methods were compared, and the experimental results indicate that compared to free fall motion, adopting the method proposed in this paper reduces the maximum acceleration of the robot when it touches the wall to 69.1 m/s2, effectively reducing the impact force upon landing. Finally, in the actual experiment, we positioned the robot 0.85 m away from the wall and applied a forward pushing force. We observed that the robot could stably land on the wall, and the impact force was within the range acceptable to the robot, confirming the practical effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

A revised reaction mechanism of CF3I synthesis catalyzedby activated carbon is investigated with quantum chemistry methodsusing density functional theory (DFT). The adsorption configurationsof possible intermediates are carefully examined. The reaction pathwayand related transition states are also analyzed. According to ourcalculations, first, the dehydrofluorination of CHF3iscatalyzed by −COOH groups, which possesses the highest barrierand is accordingly identified as the rate-determining step. Second,the difluorocarbene disproportionation over graphite (001) surfaceproceeds instead of dimerization. The next reaction steps involvingthe association of fluoromethine and trifluoromethyl, the fluorineabstractions between intermediates and the iodine abstractions bythe desorbed CF3and CF2CF3frommolecular iodine are also feasible over graphite (001) surfaces. Itis also found that the coke deposition in experiments is due to thefluorine abstraction from fluoromethine. This revised mechanism isin agreement with available experimental data and our theoreticalcomputations. [ABSTRACT FROM AUTHOR]

In this paper, one newly recorded family. Argasidae, and four newly recorded species,A. vespertilionis (Latreille, 1802), Ixodes vespertilionis Koch, I. nuttallianus Schulze, and I. crenulatus Koch, are summarized. The family and species belong to Ixodoidea and are distributed in Hubei Province, China. [ABSTRACT FROM AUTHOR]