The design of exoskeleton lower limbs rehabilitation robot

To achieve human lower limbs rehabilitation training, the exoskeleton lower limbs rehabilitation robot is designed. Through respective motor driving, the retarding mechanism and telescopic adjusting mechanism, the function of human walking is accomplished. After the design of the mechanical structure, the finite element analysis is carried out on the important parts and the control system is achieved by Single Chip Microcomputer.

A Clinical Randomized Controlled Study of Low-Frequency rTMS Therapy on Lower Limb Motor Dysfunction after Stroke

Objective:To investigate the efficacy and safety of low-frequency repetitive transcranial magnetic stimulation(rTMS)for the treatment of lower limb motor dysfunction after stroke.Methods:A total of 96 patients with stroke and lower limb motor dysfunction were enrolled in this study,and were randomly divided into the experimental group and the sham stimulation group using the method of calculator-generated random numbers.Both groups received conventional medication and rehabilitation therapy.The experimental group received 4 weeks of 1 Hz rTMS treatment in the primary cortical motor area(M1)of the healthy side,with the treatment coil tangent to the skull surface;the sham stimulation group underwent the same procedures as the experimental group,but the treatment coil was perpendicular to the skull surface instead.Lower-extremity subscale of the Fugl-Meyer Assessment(FMA-LE),Berg Balance Scale(BBS),gait analysis,and lower-extremity surface electromyography(LESEM)were performed in both groups before and after rTMS treatment.Results:All 96 patients completed the test with no shedding and no adverse reactions.After treatment,the FMA-LE score and BBS score of the 2 groups of patients were significantly improved as compared with the pre-treatment(P<0.05),and the TUG test time was reduced as compared with the pre-treatment(P<0.05).The true stimulation group had greater improvement in all assessment indexes than that of the sham stimulation group(P<0.05).After treatment,the electromyographic activity of the tibialis anterior and rectus femoris muscles in the true simulation group improved significantly.The step length,step speed,and step frequency were also significantly improved in both groups after treatment,and the symmetrical ratio of step length and support time was reduced(P<0.05).Comparison between the groups revealed that the true simulation group significantly improved after rTMS treatment as compared to the sham stimulation group(P<0.05).Conclusion:1Hz rTMS treatment safely and effectively improved motor and balance function in patients with post-stroke lower limb motor dysfunction.

Structure design and analysis of aid walking mechanism for a lower limb rehabilitation robot

In order to improve the rehabilitative effect of users＇ recovery training and reduce the production cost of rehabilitation institution, this paper designs an aid walking mechanism for a lower limb rehabilitation robot which achieves the movement of transmission by use of the interrelationship between hip and knee. Using single chip micyoco （SCM） control technology to achieve the coordinated operation of the entire mechanical institution, this aid walking mechanism simulates the walking gait. Besides, this paper also verifies that materials＇ strength meet the design requirements by Solidworks simulation stress-strain analysis module.

Digital Design of Multi-Functional Rehabilitation Robot

The mechanical structure as well as the schematic organization has been designed to achieve lower limb rehabilitation training function; Solidworks has been used to model the robot. And the robot has been optimized by the means of human-interference engineering. The primary components of the robot have been analyzed by Ansys workbench.

Motion Planning for a Cable-Driven Lower Limb Rehabilitation Robot with Movable Distal Anchor Points

This article introduces a cable-driven lower limb rehabilitation robot with movable distal anchor points(M-CDLR).The traditional cable-driven parallel robots(CDPRs)control the moving platform by changing the length of cables,M-CDLR can also adjust the position of the distal anchor point when the moving platform moves.The M-CDLR this article proposed has gait and single-leg training modes,which correspond to the plane and space motion of the moving platform,respectively.After introducing the system structure configuration,the generalized kinematics and dynamics of M-CDLR are established.The fully constrained CDPRs can provide more stable rehabilitation training than the under-constrained one but requires more cables.Therefore,a motion planning method for the movable distal anchor point of M-CDLR is proposed to realize the theoretically fully constrained with fewer cables.Then the expected trajectory of the moving platform is obtained from the motion capture experiment,and the motion planning of M-CDLR under two training modes is simulated.The simulation results verify the effectiveness of the proposed motion planning method.This study serves as a basic theoretical study of the structure optimization and control strategy of M-CDLR.

Compliant Control of Lower Limb Rehabilitation Exoskeleton Robot Based on Flexible Transmission

To ensure the safety, comfort, and effectiveness of lower limb rehabilitation exoskeleton robots in the rehabilitation training process, compliance is a prerequisite for human–machine interaction safety. First, under the premise of considering the mechanical structure of the lower limb rehabilitation exoskeleton robot (LLRER), when conducting the dynamic transmission of the exoskeleton knee joint, the soft axis is added to ensure that the rotation motion and torque are flexibly transmitted to any position to achieve flexible force transmission. Second, to realize the active compliance control of LLRER, the sliding mode impedance closed-loop controller is developed based on the kinematics and dynamics model of LLRER, and the stability of the designed control system is verified by Lyapunov method. Then the experiment is designed to track the collected bicycle rehabilitation motion data stably, and the algorithm and dynamic model are verified to satisfy the experimental requirements. Finally, aiming at the transmission efficiency and response performance of the soft shaft in the torque transmission process of the knee joint, the soft shaft transmission performance test is carried out to test the soft shaft transmission performance and realize the compliance of the LLRER, so as to ensure that the rehabilitation training can be carried out in a safe and comfortable interactive environment. Through the design of rehabilitation exercise training, it is verified that the LLRER of flexible transmission under sliding mode impedance control has good adaptability in the actual environment, and can achieve accurate and flexible control. During the experiment, the effectiveness of monitoring rehabilitation training is brought through the respiratory belt.

Optimal Predictive Impedance Control in the Presence of Uncertainty for a Lower Limb Rehabilitation Robot

As an innovative concept,an optimal predictive impedance controlle is introduced here to control a lower limb rehabilitation robo in the presence of uncertainty.The desired impedance law is considered to propose a conventional model-based impedance controller for the LLRR.However,external disturbances,model imperfection,and parameters uncertainties reduce the performance of the controller in practice.In order to cope with these uncertainties,an optimal predictive compensator is introduced as a solution for a proposed convex optimization problem,which is performed on a forward finite-length horizon.As a result,the LLRR has the desired behavior even in an uncertain environment.The performance and efficiency of the proposed controller are verified by the simulation results.

Review of human–robot coordination control for rehabilitation based on motor function evaluation

As a wearable and intelligent system, a lower limb exoskeleton rehabilitation robot can provide auxiliary rehabilitation training for patients with lower limb walking impairment/loss and address the existing problem of insufficient medical resources. One of the main elements of such a human–robot coupling system is a control system to ensure human–robot coordination. This review aims to summarise the development of human–robot coordination control and the associated research achievements and provide insight into the research challenges in promoting innovative design in such control systems. The patients’ functional disorders and clinical rehabilitation needs regarding lower limbs are analysed in detail, forming the basis for the human–robot coordination of lower limb rehabilitation robots. Then, human–robot coordination is discussed in terms of three aspects: modelling, perception and control. Based on the reviewed research, the demand for robotic rehabilitation, modelling for human–robot coupling systems with new structures and assessment methods with different etiologies based on multi-mode sensors are discussed in detail, suggesting development directions of human–robot coordination and providing a reference for relevant research.