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The lower limbs exoskeleton rehabilitation robot (LLERR) has been used widely in rehabilitation training of human lower limb injury, where the control research of LLERR is still a hot point in robotics. Therefore, in this paper, a trajectory tracking adaptive control based on human gait is proposed. Where, the real gait trajectory of human body mechanism by using NOKOV motion capture system is used in control system design. In the simulation results, the dynamics model uncertainty are also considered, and the real gait trajectory data of human body is used to the control system. According to the simulation results, when there is uncertainty in the LLERR model, the proposed trajectory tracking adaptive control method can improve the accuracy and reliability of the trajectory tracking, which makes it suitable for different patients. By adaptive control, the uncertain part of the LLERR is compensated, and the structure parameters of the robot are obtained.

Lower limb rehabilitation robots have been widely used in medical treatment in recent years. The safety of robot in rehabilitation training should be considered. In this paper, the method to analyze complicated inverse kinematics and forward dynamics of lower limb rehabilitation robot is studied. Because of the mathematical model of lower limb is difficult to establish, the OpenSim software is used to simulate and analyze the human gait data which collected by the NOKOV optical motion capture system. According to the inverse kinematics simulation, the curve of each joint angle changing over time is obtained, and the reaction force acting on the ground is obtained through the forward dynamics simulation.

This study demonstrates an efficient method for the synthesis of thermoreversible cross-linked ethylene/propylene rubbers (EPRs) via two steps; in the first step, a functional olefin monomer containing a furan group (FO) is designed and the ethylene/propylene/FO terpolymerization catalyzed by a traditional Ziegler–Natta catalyst is implemented; in the second step, a cross-linked network is constructed via Diels–Alder (DA) click reaction between the bismaleimide and pendant furan groups in the EPR chains. Via polymerization, the FO content in the copolymers was tailored in relatively wide range from 1.1 mol% to 9.7 mol%; this provided various cross-linking precursory groups for the DA reaction. Moreover, the cross-linking density could be adjusted via not only the amount of the inserted furan group but also the ratio of furan to bismaleimide. These solid thermoreversibile EP rubbers could perform their de-cross-linking above 110 °C and re-form the network below 85 °C in a heating–cooling cycle not only in the static measurement of FTIR, but also in the dynamic test of DMA. The mechanical properties of the resulting products with varied cross-linking densities were compared with that of the non-cross-linked polymer and proved to be of much higher modulus. This thermoreversible cross-linking behavior also provided a new strategy for local-repairing of any crack in rubber products.

Mutations in myosin XV are responsible for congenital profound deafness DFNB3 in humans and deafness and vestibular defects in shaker 2 mice. By combining direct cDNA analyses with a comparison of 95.2 kb of genomic DNA sequence from human chromosome 17p11.2 and 88.4 kb from the homologous region on mouse chromosome 11, we have determined the genomic and mRNA structures of the human (MYO15) and mouse (Myo15) myosin XV genes. Our results indicate that full-length myosin XV transcripts contain 66 exons, are >12 kb in length, and encode 365-kDa proteins that are unique among myosins in possessing very long ∼1200-aa N-terminal extensions preceding their conserved motor domains. The tail regions of the myosin XV proteins contain two MyTH4 domains, two regions with similarity to the membrane attachment FERM domain, and a putative SH3 domain. Northern and dot blot analyses revealed that myosin XV is expressed in the pituitary gland in both humans and mice. Myosin XV transcripts were also observed by in situ hybridization within areas corresponding to the sensory epithelia of the cochlea and vestibular systems in the developing mouse inner ear. Immunostaining of adult mouse organ of Corti revealed that myosin XV protein is concentrated within the cuticular plate and stereocilia of cochlear sensory hair cells. These results indicate a likely role for myosin XV in the formation or maintenance of the unique actin-rich structures of inner ear sensory hair cells.