Adaptive Robust Control for a Lower Limbs Rehabilitation Robot Running Under Passive Training Mode

This paper focuses on the problem of the adaptive robust control of a lower limbs rehabilitation robot(LLRR) that is a nonlinear system running under passive training mode. In reality, uncertainties including modeling error, initial condition deviation, friction force and other unknown external disturbances always exist in a LLRR system. So, it is necessary to consider the uncertainties in the unilateral man-machine dynamical model of the LLRR we described. In the dynamical model, uncertainties are(possibly fast) time-varying and bounded. However, the bounds are unknown. Based on the dynamical model, we design an adaptive robust control with an adaptive law that is leakagetype based and on the framework of Udwadia-Kalaba theory to compensate for the uncertainties and to realize tracking control of the LLRR. Furthermore, the effectiveness of designed control is shown with numerical simulations.

Auditory P300 as an Indicator in Effectiveness of Robot-Assisted Lower Limb Rehabilitation Training among Hemiplegic Patients after Ischemic Stroke

Background: Robot-assisted lower limb rehabilitation training in early stage could improve the limb function among hemiplegic patients caused by ischemic stroke. P300 potential changes have importantly clinical value for evaluating the improvement in nerve function during the training as one of the objective targets. Methods: Sixty hemiplegic patients after stroke were randomly divided into a Lokomat group (30 cases) and a control group (30 cases). The Lokomat group received Lokomat rehabilitation while the control group only received traditional rehabilitation. The gait parameters and the balance ability were evaluated by the K421GAITRite analysis system and the Berg Balance Scale (BBS);ERP components including N100, N200, P200 and P300 potential were evaluated by a muscle electric inducing potentiometer. Results: There were no significant differences in BBS and gait parameters (P > 0.05), as well as in amplitude and incubation periods (IP) (P > 0.05) between the two groups before training. After 8 weeks treatment, the total (48.88 ± 3.68), static (26.40 ± 3.14) and dynamic (22.64 ± 3.68) balance scores improved significantly;the pace (59.22 ± 4.67), stride length (19.04 ± 2.24), feet wide (98.02 ± 7.97) and walking velocity (84.86 ± 9.88) and IP of N200 and P300 shortened obviously and P300 amplitude increased significantly in robot group (P < 0.05). Conclusion: This demonstrated that robot-assisted lower limb rehabilitation training in early stage could improve the limb function among hemiplegic patients caused by ischemic stroke. P300 may be considered as an indicator of neurological function improvement and effective robot-assisted lower limb rehabilitation training.

A Review on Lower Limb Rehabilitation Exoskeleton Robots

Lower limb rehabilitation exoskeleton robots integrate sensing, control, and other technologies and exhibit the characteristics of bionics, robotics, information and control science, medicine, and other interdisciplinary areas. In this review, the typical products and prototypes of lower limb exoskeleton rehabilitation robots are introduced and stateof-the-art techniques are analyzed and summarized. Because the goal of rehabilitation training is to recover patients’ sporting ability to the normal level, studying the human gait is the foundation of lower limb exoskeleton rehabilitation robot research. Therefore, this review critically evaluates research progress in human gait analysis and systematically summarizes developments in the mechanical design and control of lower limb rehabilitation exoskeleton robots. From the performance of typical prototypes, it can be deduced that these robots can be connected to human limbs as wearable forms;further, it is possible to control robot movement at each joint to simulate normal gait and drive the patient’s limb to realize robot-assisted rehabilitation training. Therefore human–robot integration is one of the most important research directions, and in this context, rigid-flexible-soft hybrid structure design, customized personalized gait generation, and multimodal information fusion are three key technologies.

Research Progress of Lower Limb Rehabilitation Robots in China's Mainland

The number of people with lower limb disabilities caused by stroke, traffic accidents and work-related injuries is increasing sharply every year in China's Mainland, and the corresponding number of rehabilitation therapists is obviously insufficient. To solve this problem, domestic large hospitals have introduced advanced lower limb rehabilitation robots from abroad. However, such robots are expensive and the number of them cannot meet the needs of patients. As a result, many universities and colleges in China's Mainland have launched research on this issue. This paper collects and collates the research literature, gives the mature and typical structure and control system design scheme in China's Mainland, and lists some representative research results. Finally, the rehabilitation effect of these lower limb rehabilitation robots is evaluated.

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.

Adaptive patient-cooperative compliant control of lower limb rehabilitation robot

With the increase in the number of stroke patients,there is a growing demand for rehabilitation training.Robot-assisted training is expected to play a crucial role in meeting this demand.To ensure the safety and comfort of patients during rehabilitation training,it is important to have a patient-cooperative compliant control system for rehabilitation robots.In order to enhance the motion compliance of patients during rehabilitation training,a hierarchical adaptive patient-cooperative compliant control strategy that includes patient-passive exercise and patient-cooperative exercise is proposed.A low-level adaptive backstepping position controller is selected to ensure accurate tracking of the desired trajectory.At the high-level,an adaptive admittance controller is employed to plan the desired trajectory based on the interaction force between the patient and the robot.The results of the patient-robot cooperation experiment on a rehabilitation robot show a significant improvement in tracking trajectory,with a decrease of 76.45%in the dimensionless squared jerk(DSJ)and a decrease of 15.38%in the normalized root mean square deviation(NRMSD)when using the adaptive admittance controller.The proposed adaptive patient-cooperative control strategy effectively enhances the compliance of robot movements,thereby ensuring the safety and comfort of patients during rehabilitation training.

Different frequencies of repetitive transcranial magnetic stimulation combined with local injection of botulinum toxin type A for post-stroke lower limb spasticity:study protocol for a prospective,single-center,non-randomized,controlled clinical trial

No definite consensus has currently been reached regarding the safety and efficacy of low-or high-frequency repetitive transcranial magnetic stimulation in the treatment of post-stroke muscle spasticity.The latest research indicates that when combined with local injections of botulinum toxin type A,it is more effective on post-stroke muscle spasticity than local injections of botulinum toxin type A alone.We designed a prospective,single-center,non-randomized,controlled clinical trial to investigate the safety and effica cy of different frequencies of repetitive transcranial magnetic stimulation combined with local injections of botulinum toxin type A in treating post-stroke lower limb muscle spasticity to determine an optimal therapeutic regimen.This trial will enroll 150 patients with post-stroke muscle spasticity admitted to the Department of Rehabilitation Medicine at the First Affiliated Hos pital of China Medical Unive rsity.All enrolled patients will undergo ro utine rehabilitation training and will be divided into five groups in-30 per group) according to the particular area of cerebral infa rction and treatment methods.G roup A:Patients with massive cerebral infarction will be given local injections of botulinum toxin type A and low-frequency(1 Hz)repetitive transcranial magnetic stimulation on the contralate ral side;G roup B:Patients with non-massive cerebral infarction will be given local injections of botulinum toxin type A and high-frequency(10-20 Hz) re petitive transcranial magnetic stimulation on the affected side;G roup C:Patients with massive/non-massive cerebral infarction will be given local injections of botulinum toxin type A;G roup D:Patients with massive cerebral infarction will be given low-frequency(1 Hz) repetitive transcranial magnetic stimulation on the contralate ral side;and G roup E:Patients with non-massive cerebral infa rction will be given high-frequency(10-20 Hz) repetitive transcranial magnetic stimulation on the affected side.The primary outcome measure of this trial is a modified Ashwo rth scale score from 1 day before treatment to 12 months after treatment.Secondary outcome measures include Fugl-M eyer Assessment of Lower Extremity,Visual Analogue Scale,modified Barthel index,and Berg Balance Scale scores for the same time as specified for primary outcome measures.The safety indicator is the incidence of adverse events at 3-12 months after treatment.We hope to draw a definite conclusion on whether there are diffe rences in the safety and efficacy of low-or high-frequency repetitive transcranial magnetic stimulation combined with botulinum toxin type A injections in the treatment of patients with post-stroke lower limb spasticity under strict grouping and standardized operation,thereby screening out the optimal therapeutic regimen.The study protocol was approved by the Medical Ethics Committee of the First Affiliated Hospital of China Medical University(approval No.[2021] 2021-333-3) on August 19,2021.The trial was registe red with the Chinese Clinical Trial Registry(Registration No.ChiCTR2100052180) on October 21,2021.The protocol version is 1.1.

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.

基于模糊控制的上肢康复机器人变导纳控制

传统固定参数的导纳模型无法对上肢康复机器人的柔顺性实时调节,而现有变参数导纳模型需要结合实际康复需求进行改善。为此,以自主研发的串并混联的末端牵引式上肢康复机器人为研究对象,结合模糊控制与导纳控制,提出了一种面向实际康复需求的新型变导纳控制策略,制定了4条有利于康复效率与安全的模糊规则。该策略利用交互力误差及其变化率作为模糊控制输入,实时改变导纳模型的参数,实现柔顺性自主调节。仿真和实验结果验证了所提出的变导纳模型控制策略可行性和所制定的4条模糊规则的有效性。在患者可适应训练强度的场景中,相较于固定导纳模型,变导纳模型追踪给定路径时产生的冗余路径最多可降低56.13%,提高了康复训练效率;当康复运动超出患者可承受范围时,变导纳模型可提前0.5 s改变追踪路径,提高了康复的安全性。

下肢康复机器人整合运动想象在Pusher综合征中的应用

目的:探讨下肢康复机器人整合运动想象在Pusher综合征中的应用效果。方法:选取卒中后Pusher综合征患者63例,随机分为运动想象组、机器人训练组、整合训练组,每组21例,三组分别实施运动想象训练、机器人训练、机器人整合运动想象训练。比较三组倾斜程度(BLS)、平衡能力(BBS)、步行能力(TUGT、DGI)、日常生活能力(MBI)、康复信心(CaSM)、神经营养因子水平。结果:整合训练组康复治疗后BLS、BBS、TUGT、DGI、MBI、CaSM评分与神经营养因子水平优于运动想象组、机器人训练组(P<0.05)。结论:下肢康复机器人训练整合运动想象能促进Pusher综合征患者的功能康复。

一种新型足底驱动式康复机器人的设计与分析

针对当前下肢运动障碍患者较多,不同康复阶段的患者,康复训练需求存在差异性的现状,设计了一种运动轨迹和幅度都可以调节的足底驱动式下肢康复机器人。该机器人包括一个靠背角度、椅面高度可调的座椅和一组运动轨迹、幅度可设定的五杆运动机构,能够适用于不同身高和不同康复期的患者。首先,依据患者的下肢训练需求完成了康复机器人的结构设计;然后,建立了足底驱动式康复机器人和人体联合运动的模型,并对该模型进行了运动学正分析,从而证明所设计的足底驱动式康复机器人有实现个性化下肢康复训练的可能性;最后,分析了下肢运动轨迹,结果表明该机器人可以实现正常的步态运动。

下肢康复训练机器人联合等速肌力训练对老年脑卒中偏瘫患者神经功能、步行能力、Lovett肌力分级及平衡能力的影响

目的分析下肢康复训练机器人联合等速肌力训练对老年脑卒中偏瘫患者神经功能、步行能力、Lovett肌力分级及平衡能力的影响。方法回顾性分析2022年1月至12月于中国中医科学院西苑医院康复医学科接受康复治疗至少8周的86例老年脑卒中偏瘫患者的临床资料,依据训练方法不同分为联合组(n=43)和对照组(n=43)。对照组行常规康复训练联合等速肌力训练,联合组在对照组基础上行下肢康复训练机器人训练。观察分析两组训练前及训练8周后神经功能、步行能力、Lovett肌力分级、平衡能力、不良反应。结果训练后,两组NIHSS评分、Rankin评分均较训练前降低,且联合组NIHSS评分、Rankin评分分别为(10.96±1.32)、(2.12±0.24)分,均低于对照组[(15.93±1.79)、(2.65±0.29)分],差异均有统计学意义(P<0.05)。训练后,两组FAC高分级均较训练前增加,且联合组FAC及Lovett肌力高分级比例均大于对照组,差异均有统计学意义(P<0.05)。训练后,两组BBS评分均较训练前升高,且联合组BBS评分(45.19±4.83)分,高于对照组[(38.76±4.18)分],差异均有统计学意义(P<0.05)。两组均无显著不良反应。结论下肢康复训练机器人联合等速肌力训练可改善老年脑卒中偏瘫患者神经功能,提高其步行能力、Lovett肌力分级及平衡能力,安全性高。

早期悬吊保护下智能助行训练对脑卒中后运动和行走功能的效果

目的探讨脑卒中偏瘫患者早期应用悬吊保护下智能助力步行对下肢运动功能的康复效果。方法2020年10月至2023年3月,北京博爱医院脑卒中偏瘫早期住院患者42例,随机分为对照组(n=21)和试验组(n=21)。两组均接受常规康复,对照组在天轨悬吊保护下行常规步行训练,试验组在天轨悬吊保护下穿戴智能助力步行器进行训练,共4周。治疗前后,采用Fugl-Meyer评定量表(FMA)、FMA-平衡功能(FMA-B)和无线传感三维步态分析进行评定。结果训练后,两组患侧肢体FMA和FMA-B评分,步频、步速、患侧步长、患侧单支撑相、髋关节屈曲最大角度、膝关节屈曲最大角度均改善(|t|>2.230,P<0.05),且试验组优于对照组(|t|>2.140,P<0.05)。结论早期介入智能助力步行训练能更好提高脑卒中偏瘫患者运动、平衡和行走功能。

绳索驱动下肢训练机器人系统运动稳定性分析

针对绳索驱动下肢训练机器人的稳定性问题,本文建立了绳索驱动下肢训练机器人的运动学和动力学模型,给出了绳索拉力优化解的计算表达式,并推导获得了机器人的系统刚度解析表达式。考虑不同训练对象承受运动强度的能力不同,定义了速度影响函数。综合考虑绳索拉力、系统刚度和速度影响函数等因素定义了机器人系统的运动稳定性评价指标,并通过稳定工作空间、抗干扰稳定工作空间和不同训练轨迹的实例计算明确了机器人工作空间内中上部区域的运动稳定性能更好,为运动支链中的过轮运动规划和训练任务规划提供了理论依据。

下肢康复机器人联合头针治疗对老年缺血性卒中患者步行效率和协调功能影响调查

目的分析下肢康复机器人联合头针治疗对老年缺血性卒中患者步行效率和协调功能的影响。方法本研究为前瞻性研究,连续纳入2022年12月—2023年6月在商丘市中医院治疗的老年缺血性卒中患者为研究对象,按照随机数表将其分为对照组和观察组。对照组患者在常规治疗的基础上增加平地行走式下肢康复机器人康复训练(30 min/次,每周3次);观察组患者在常规治疗的基础上增加平地行走式下肢康复机器人康复训练联合头针治疗(留针30 min,1次/d,每周5 d),两组均治疗4周。在治疗前及治疗4周后采用日常生活活动量表(activity of daily living scale,ADL)评估患者日常生活能力;采用Fugl-Meyer评估(Fugl-Meyer assessment,FMA)量表评估下肢运动功能;采用Berg平衡量表评估平衡功能;采用功能性步行(functional ambulation category,FAC)量表、6 min步行距离和起立行走计时(timed up and go,TUG)评估步行功能;采用徒手肌力检测(manual muscle testing,MMT)评估患者股四头肌、腘绳肌肌力;采用Prokin系统记录平均轨迹误差(absolute trajectory error,ATE)及完成时间,评估患者的本体感觉功能。另外,采用表面肌电分析系统分析患者股直肌、腘绳肌、胫骨前肌、腓肠肌内侧头的肌电均方根(root mean square,RMS)值。结果治疗后两组患者的ADL评分均高于本组治疗前,且治疗后观察组的ADL评分高于对照组[(85.21±7.55)分vs.(73.51±6.90)分,P<0.001]。治疗后两组的FMA量表评分和Berg平衡量表评分均高于本组治疗前,且治疗后观察组的FMA量表评分[(28.74±3.14)分vs.(22.31±2.77)分,P<0.001]和Berg平衡量表评分[(41.82±3.21)分vs.(30.49±2.78)分,P<0.001]均高于对照组。治疗后两组患者的FAC量表评分、6 min步行距离均优于治疗前,TUG短于治疗前;治疗后观察组的上述指标均优于对照组[FAC量表评分:(3.89±0.41)分vs.(2.87±0.34)分,P<0.001;6 mi n步行距离:(314.38±18.93)m vs.(269.05±20.31)m,P<0.001;TUG:(24.93±4.24)s vs.(29.84±4.85)s,P<0.001]。治疗后两组患者股四头肌、腘绳肌的MMT分级均高于治疗前,且治疗后观察组的上述指标均高于对照组(均P<0.05)。治疗后两组患者的ATE及完成时间均低于治疗前,且治疗后观察组的上述指标均低于对照组[ATE:(47.57±5.12)%vs.(55.43±5.49)%,P<0.001;完成时间:(80.43±6.78)s vs.(91.27±8.01)s,P<0.001]。治疗后两组患者股直肌、腘绳肌、胫骨前肌、腓肠肌内侧头的RMS值均高于治疗前,且治疗后观察组高于对照组,差异有统计学意义。结论采用下肢康复机器人联合头针治疗可显著改善老年缺血性卒中患者的步行效率和协调功能,提高患者的日常生活能力、本体感觉功能及肌电水平。

穿戴式外骨骼康复机器人结合Bobath技术对脑卒中偏瘫患者的影响

目的探讨穿戴式外骨骼康复机器人结合Bobath技术对脑卒中偏瘫患者步态、平衡能力、下肢运动Fugl-Meyer功能量表(FMA)评分的影响。方法纳入2020年11月—2022年11月我院收治的78例脑卒中偏瘫患者,按照数字列表法随机分为观察组与对照组,每组39例,对照组予以Bobath技术训练,观察组在对照组基础上予以穿戴式外骨骼康复机器人训练,干预8周。比较两组干预前后的步态参数(步频、步速、跨步长比率)、平衡能力[Berg平衡量表(BBS)]、下肢运动功能FMA评分、日常生活活动能力[改良Barthel指数(MBI)]、下肢肌力恢复情况(屈髋肌力、伸膝肌力)。结果干预前,两组各指标差异无统计学意义(P>0.05);干预后,两组步频、步速、跨步长比率、BBS评分、下肢FMA评分、MBI评分、屈髋肌力、伸膝肌力较干预前显著升高(均P<0.05),观察组步频、步速、跨步长比率、BBS评分、下肢FMA评分、MBI评分、屈髋肌力、伸膝肌力高于对照组(均P<0.05)。结论穿戴式外骨骼康复机器人结合Bobath技术可改善脑卒中偏瘫患者步态和平衡能力,促进下肢运动功能恢复,提高日常生活活动能力,增强患者下肢肌力。

下肢康复机器人联合IPC对脑损伤后肢体运动功能障碍患者下肢深静脉血栓预防效果

目的探讨下肢康复机器人联合间歇充气加压装置(IPC)对脑损伤后肢体运动功能障碍患者下肢深静脉血栓形成(DVT)的预防效果。方法通过便利抽样法选取本院2020年12月—2021年12月住院的脑损伤后肢体运动功能障碍患者90例,根据治疗方法的不同将其分为对照组和观察组,每组45例。对照组给予常规康复训练及IPC治疗,观察组在对照组基础上给予下肢康复机器人治疗,两组均在治疗3月后进行效果评价,比较两组临床疗效、美国国立卫生研究院卒中量表(NIHSS)评分、改良Barthel指数(MBI)评分、凝血-纤溶系统指标、下肢深静脉血流动力学参数、DVT发生率。结果观察组临床总有效率高于对照组(P<0.05)。观察组治疗后NIHSS评分低于对照组(P<0.05),观察组治疗后MBI评分高于对照组(P<0.05)。观察组治疗后D-二聚体(D-D)、纤维蛋白降解产物(FDP)均低于对照组,观察组治疗后凝血活酶时间(APTT)、凝血酶原时间(PT)均高于对照组(P<0.05)。观察组治疗后下肢腘静脉、股静脉、髂外静脉平均血流速度(Vm)均高于对照组(P<0.05)。观察组DVT发生率低于对照组(P<0.05)。结论下肢康复机器人联合IPC可有效改善脑损伤后肢体运动功能障碍患者神经功能及下肢血液流动速度,提高日常生活能力,纠正血液高凝状态,降低DVT发生率,值得借鉴。

适应人体重心起伏的悬吊减重康复系统设计

减重系统对下肢疾病患者的行走康复训练有重要影响。现有的下肢康复外骨骼减重装置大多只考虑如何减去患者体重的百分比,而忽略了患者身体重心的起伏。由于外骨骼的骨盆支架在竖直方向运动轨迹固定,患者步态的微小变化就会导致重心高度与骨盆支架运动轨迹不符,这一差异会作用到患者的骨盆位置,影响下肢关节的活动,并产生额外的风险。针对这一问题,提出通过采集足底压力来预测重心位置变化,并利用获得的重心轨迹解算出应施加的减重力方法,为患者训练提供安全有效的减重系统。所提方法的可行性已获仿真证实,并在研发的外骨骼减重系统上获得实际验证,模糊控制器跟踪重心轨迹的误差相比PID控制减少了21.2%,稳态误差维持在±1 mm范围内,髋膝关节的活动范围相比常规减重分别增加了14.36%和13.77%。

下肢康复外骨骼机器人设计与性能分析

为了更好地辅助偏瘫患者的康复训练,设计了一种基于盘式电机驱动的下肢康复外骨骼机器人,并通过助力效果可视化研究与性能分析来验证其不同康复训练模式的有效性。首先,对下肢康复外骨骼机器人的结构进行了详细设计,并利用OpenSim软件进行了人机耦合的生物力学分析。然后,开展了基于位置跟踪控制的被动康复训练实验以及抗阻康复训练实验并采集表面肌电信号,验证了所设计下肢康复外骨骼机器人在不同模式下辅助患者康复训练的有效性。结果表明,穿戴下肢康复外骨骼机器人能使人体膝关节的力矩减小50%左右;在被动康复训练实验中,跟随误差为-4°~8°,且人体下肢目标肌群的肌肉激活度呈明显的周期性变化;在抗阻康复训练实验中,人体下肢目标肌群的肌肉激活度随负重的增加而提高。所设计的下肢康复外骨骼机器人具有良好的灵敏性和跟随性,其被动及抗阻康复训练模式均有助于偏瘫患者下肢的康复,具有广阔的应用前景。