The extended optima straints of miss distance and Schwartz inequality. To reduce guidance law with terminal conmpact angle is derived by the terminal acceleration and eliminate gravity disturbance absolutely, the obje...The extended optima straints of miss distance and Schwartz inequality. To reduce guidance law with terminal conmpact angle is derived by the terminal acceleration and eliminate gravity disturbance absolutely, the object function, which designs the weight of control command to be the power function of time-to-go＇s reciprocal, is given. And the gravity is considered when building the state equation. Based on the parsing express of the guidance command change with varying time and adjoint system analysis method, the command characteristics and the non-dimensional miss distance of the guidance law are analyzed, a design principle of guidance order coefficients is discussed. Finally, based on the requirement of engineering, the method to calculate the guidance condition and maximal required acceleration of the guidance law is given. The simulation demonstrates that not only the guidance law can satisfy the terminal position and impact angle constraints, but also the terminal acceleration can be converged toward zero, which will support a good situation for the terminal angle of attacking control.展开更多
背景:卓越的下肢移动能力被视作是赢得比赛的先决条件之一,可穿戴式阻力训练能够有效克服传统力量训练在提高下肢移动能力时所面临的能力转化效率不足的问题。考虑到基于不同身体部位的可穿戴式阻力训练对下肢移动能力的影响可能存在显...背景:卓越的下肢移动能力被视作是赢得比赛的先决条件之一,可穿戴式阻力训练能够有效克服传统力量训练在提高下肢移动能力时所面临的能力转化效率不足的问题。考虑到基于不同身体部位的可穿戴式阻力训练对下肢移动能力的影响可能存在显著的差异化特征,深入回顾并总结其具体应用策略以及急性与慢性干预效果则显得尤为重要。目的:旨在通过梳理与分析基于不同身体部位的可穿戴式阻力训练在下肢移动能力方面的急性和慢性干预效果,从而为优化下肢运动能力的应用策略提供思路借鉴和方法参考。方法:检索各大数据库建库至2023年10月发表的文献,在中国知网、万方、维普、Web of Science、Medline、SPORTDiscus和PubMed数据库进行文献检索,以“手臂,前臂,肢体,腿,下肢,背,躯干,阻力,重量,负重,冲刺,灵敏,变向”为中文检索词,以“arm,forearm,limb,leg,lower extremity,vest,trunk,resist,weight,load,sprint,agility,change of direction”为英文检索词,筛选检索结果后最终纳入文献60篇进行综述分析。结果与结论:①6%-20%BM的躯干负重适用于优化加速跑,≤6%BM的躯干负重适用于优化高速跑,5%BM的躯干负重适用于优化变向移动;前臂、小腿或大腿负重多采用1%BM或2%BM。②躯干负重通过增加垂直负重来优化下肢拉伸-缩短循环的功能表现、提升地面反作用力的利用效率和增强全身肌群的协调稳定控制;前臂负重可有效增强上肢摆臂驱动力、提升下肢冲刺推进力和优化肢体间的协同配合效率;小腿负重可对髋关节的功能执行形成限制,进而导致膝或踝关节产生局部性的负荷刺激加重和代偿性的运动功能增强;大腿负重会部分限制膝关节的伸展峰值角度和伸展速度,针对髋关节部位形成特定的负荷刺激,显著提高其旋转动能输出。③在进行更大角度的变向移动时,小腿负重比大腿负重所产生的影响更为显著,大腿负重刺激有助于增强动力输出,小腿负重刺激有助于提升稳定控制与方向变换。④目前,可穿戴式阻力训练已被证明是改善冲刺和变向移动能力的有效途径,旨在提升冲刺表现的方法学策略已较为成熟,而旨在提升变向表现的最佳应用方案仍有待进一步的细化与优化,建议后续研究对此领域予以补充。展开更多
基金supported by the National Natural Science Foundation of China(50875024)
文摘The extended optima straints of miss distance and Schwartz inequality. To reduce guidance law with terminal conmpact angle is derived by the terminal acceleration and eliminate gravity disturbance absolutely, the object function, which designs the weight of control command to be the power function of time-to-go＇s reciprocal, is given. And the gravity is considered when building the state equation. Based on the parsing express of the guidance command change with varying time and adjoint system analysis method, the command characteristics and the non-dimensional miss distance of the guidance law are analyzed, a design principle of guidance order coefficients is discussed. Finally, based on the requirement of engineering, the method to calculate the guidance condition and maximal required acceleration of the guidance law is given. The simulation demonstrates that not only the guidance law can satisfy the terminal position and impact angle constraints, but also the terminal acceleration can be converged toward zero, which will support a good situation for the terminal angle of attacking control.
文摘背景:卓越的下肢移动能力被视作是赢得比赛的先决条件之一,可穿戴式阻力训练能够有效克服传统力量训练在提高下肢移动能力时所面临的能力转化效率不足的问题。考虑到基于不同身体部位的可穿戴式阻力训练对下肢移动能力的影响可能存在显著的差异化特征,深入回顾并总结其具体应用策略以及急性与慢性干预效果则显得尤为重要。目的:旨在通过梳理与分析基于不同身体部位的可穿戴式阻力训练在下肢移动能力方面的急性和慢性干预效果,从而为优化下肢运动能力的应用策略提供思路借鉴和方法参考。方法:检索各大数据库建库至2023年10月发表的文献,在中国知网、万方、维普、Web of Science、Medline、SPORTDiscus和PubMed数据库进行文献检索,以“手臂,前臂,肢体,腿,下肢,背,躯干,阻力,重量,负重,冲刺,灵敏,变向”为中文检索词,以“arm,forearm,limb,leg,lower extremity,vest,trunk,resist,weight,load,sprint,agility,change of direction”为英文检索词,筛选检索结果后最终纳入文献60篇进行综述分析。结果与结论:①6%-20%BM的躯干负重适用于优化加速跑,≤6%BM的躯干负重适用于优化高速跑,5%BM的躯干负重适用于优化变向移动;前臂、小腿或大腿负重多采用1%BM或2%BM。②躯干负重通过增加垂直负重来优化下肢拉伸-缩短循环的功能表现、提升地面反作用力的利用效率和增强全身肌群的协调稳定控制;前臂负重可有效增强上肢摆臂驱动力、提升下肢冲刺推进力和优化肢体间的协同配合效率;小腿负重可对髋关节的功能执行形成限制,进而导致膝或踝关节产生局部性的负荷刺激加重和代偿性的运动功能增强;大腿负重会部分限制膝关节的伸展峰值角度和伸展速度,针对髋关节部位形成特定的负荷刺激,显著提高其旋转动能输出。③在进行更大角度的变向移动时,小腿负重比大腿负重所产生的影响更为显著,大腿负重刺激有助于增强动力输出,小腿负重刺激有助于提升稳定控制与方向变换。④目前,可穿戴式阻力训练已被证明是改善冲刺和变向移动能力的有效途径,旨在提升冲刺表现的方法学策略已较为成熟,而旨在提升变向表现的最佳应用方案仍有待进一步的细化与优化,建议后续研究对此领域予以补充。
