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With the increase in the elderly population in China and the growing number of individuals who are unable to walk normally, research on lower limb exoskeletons is becoming increasingly important. This study proposes a complete dynamic model parameter identification scheme for the human–machine coupling model of lower limb exoskeletons. Firstly, based on the coupling model, the excitation trajectory is optimized, data collection experiments are conducted, and the dynamic parameter vector of the system is identified using the least squares method. Secondly, this lays the foundation for designing adaptive control based on RBF neural network approximation. Thirdly, the Lyapunov function is used to prove that the RBF neural network adaptive controller can achieve stable tracking of the lower limb exoskeleton. Finally, simulation analysis reveals that increasing the gains of the RBF controllers effectively reduces tracking errors. Furthermore, the tracking errors and control torques show that adaptive control based on the RBF neural network approximation works well. [ABSTRACT FROM AUTHOR]

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In this paper, a new safety control method of the jointed slope under blasting excavation is presented. The spatial distribution of blasting damage and time-history characteristic of dynamic stability around the joint were investigated carefully based on the secondary development of the explicit FE code, LS-DYNA. Results clearly indicated that the evolution law of damage and stability are opposite with the change of joint angle, and the dual-controlled mechanism of damage extension and stability fluctuation exists in the safety control of the high rock slope with joints. Then a new safety control method is proposed by implementing the equivalent Blasting Safety Control Standard (BSCS) which includes coupled effects of damage and stability. Results reveal that a critical joint angle exists, and if the inclination is larger than the threshold value, the BSCS depends on damage extension, otherwise it was determined by stability fluctuation. Finally, site experiments are implemented carefully based on the blasting excavation of the famous Baihetan high rock slope with columnar joint in China to verify the rationality of the new control approach. Sonic wave test, displacement measurement and blasting vibration test are implemented for nearly two years to track the evolution process of damage and stability of the jointed slope. Experimental results demonstrate that the new approach could improve the accuracy rate of control by 40%. [ABSTRACT FROM AUTHOR]

Reports on RASS Society activity in China. [ABSTRACT FROM PUBLISHER]

[Display omitted] An individual's level of lower limb motor function is associated with his or her disability level after stroke, and motor improvement may lead to a better prognosis and quality of life. Data from animal models show that Qizhitongluo (QZTL) capsule facilitates recovery after focal brain injury. We aimed to validate the efficacy and safety of the QZTL capsule for promoting lower limb motor recovery in poststroke patients. In this randomized, multicenter, double-blind, placebo- and active-controlled trial from 13 sites in China, participants with ischemic stroke and Fugl-Meyer motor scale (FMMS) scores of <95 were eligible for inclusion. Patients were randomly assigned in a 2:1:1 ratio to the QZTL group, Naoxintong (NXT) group or placebo group for 12 weeks at 15–28 days after the onset of stroke. The primary outcome was the change in the Lower Limb FMMS (FMMS-LL) score from baseline over the 12-week intervention period. 622 participants were randomly assigned to the QZTL group (309), NXT group (159), or placebo group (154). The FMMS-LL score increased by 4.81 points (95 % CI, 4.27–5.35) in the QZTL group, by 3.77 points (95 % CI, 3.03–4.51) in the NXT group and by 3.00 points (95 % CI, 3.03–4.51) in the placebo group at week 12. The QZTL group showed significantly larger improvements compared with the placebo group at each interview from weeks 4–12 (difference, 0.89 [0.30,1.49] at week 4, P = 0.0032; difference, 1.83[1.01,2.66] at 90 days poststroke, P < 0.0001; difference, 1.81[0.88,2.74] at week 12, P = 0.0001). The QZTL capsule is an effective treatment for lower limb motor impairment. The finding indicates that the QZTL capsule may be used as a potential new strategy for stroke rehabilitation. [ABSTRACT FROM AUTHOR]