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Strategic minerals are the cornerstone of national security and stable development. China’s strategic mineral imports are highly dependent on maritime transport, and ensuring smooth maritime routes is crucial for safeguarding the security of strategic mineral imports. This study analyzes the overall pattern of China’s strategic mineral imports and maritime routes. Taking the iron ore maritime import network as an example, the study evaluates the importance and failure impacts of key maritime routes, summarizes the risk sources of important maritime routes, and proposes corresponding security strategies. The research finds that China’s strategic mineral imports are highly dependent on maritime routes. Based on the case study of iron ore maritime transport, the importance and failure impacts of maritime routes are identified. It is suggested to build differentiated and refined response strategies, focus on the protection of the Cape of Good Hope and the Lombok Strait transport corridor network, and pay attention to the safe navigation of large vessels. The risks of maritime routes for China’s strategic minerals mainly come from three aspects: navigational passages, international disputes and war threats, and non-traditional security issues. In response, multi-domain response strategies can be implemented, including building multiple strategic pivot nodes, constructing a multidimensional early warning system and an alternative route response mechanism, strengthening the construction of cross-border rail – sea intermodal transport corridors, conducting preventive diplomatic work, improving the maritime security system, and implementing hierarchical and differentiated risk-response measures.

The capability to predict catastrophic failures and anticipate challenges relating to trafficability enables quadruped robots to adjust their planned trajectory in time to prevent any damages. In this paper, an estimation‐based method is proposed to describe the validity of the trajectory from the viewpoint of the traction performance of the terrain. The main contribution of this study lies in equipping quadruped robots with the ability to comprehend the strength characteristics of the terrain and assess the validity of trajectory planning by anticipating potential catastrophic motion failures. To this end, a novel perception method of the foot terrain interface based on proprioception is proposed to estimate terrain strength parameters. The vehicle–terrain traction model is extended to a legged locomotion pattern to estimate the traction limits of the terrain. The trafficability anticipation is driven by combining the traction limits of the terrain and the expected ground reaction force, as obtained by the model‐based predictive methods. The validity of this method is verified using a quadruped robot test platform. Results highlight the potential of the presented approach, in which the anticipation of trafficability, grounded in the understanding of the terrain strength, serves as the explicit foundation for altering trajectories to avert motion failure. [ABSTRACT FROM AUTHOR]

Reindeer (Rangifer tarandus) have lengthy seasonal migrations on land and their feet possess excellent locomotor characteristics that can adapt to complex terrains. In this study, the kinematics and vertical ground reaction force (GRF) of reindeer forelimb joints (interphalangeal joint b, metacarpophalangeal joint c, and wrist joint d) under walk, trot 1, and trot 2 were measured using a motion tracking system and Footscan pressure plates. Significant differences among different locomotor activities were observed in the joint angles, but not in changes of the joint angles (αb, αc, αd) during the stance phase. Peak vertical GRF increased as locomotor speed increased. Net joint moment, power, and work at the forelimb joints were calculated via inverse dynamics. The peak joint moment and net joint power related to the vertical GRF increased as locomotor speed increased. The feet absorbed and generated more energy at the joints. During different locomotor activities, the contribution of work of the forelimbs changed with both gait and speed. In the stance phase, the metacarpophalangeal joint absorbed more energy than the other two joints while trotting and thus performed better in elastic energy storage. The joint angles changed very little (∼5°) from 0 to 75% of the stance phase, which reflected the stability of reindeer wrist joints. Compared to typical ungulates, reindeer toe joints are more stable and the stability and energy storage of forelimb joints contribute to locomotor performance in reindeer.