共查询到19条相似文献,搜索用时 62 毫秒
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为探讨康复机器人辅助步行训练(Robot-assisted gait training,RAGT)对不完全性脊髓损伤(Incomplete spinal cord injury,ISCI)患者步行能力的影响,将16例ISCI患者随机分配至对照组(常规康复治疗+地面步行训练)及试验组(常规康复治疗+RAGT).治疗前及治疗4周、8周、12周后,分别进行下肢运动功能评分(Low extremity motor score,LEMS)及脊髓损伤步行指数II(Walking index for spinal cord injury II,WISCI II)评定.治疗后,两组患者LEMS均有提高(P < 0.05),但试验组LEMS与对照组比较差异无统计学意义(P>0.05).对照组治疗后各时间点WISCI II均较治疗前改善(P < 0.05),试验组在治疗8周及12周后WISCI II较治疗前改善(P < 0.05),但试验组WISCI II在训练12周后较对照组有明显提高(P < 0.05).RAGT与地面步行训练在提高肌力上比较无明显差异,但在改善步行能力上RAGT优于地面步行训练. 相似文献
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为了提高康复步行训练机器人的跟踪精度及安全性,提出了一种带有运动速度约束和部分记忆信息的自适应迭代学习控制方法,目的是抑制人机不确定性及速度突变对系统跟踪性能的影响.在考虑人机不确定性的基础上,建立了康复步行训练机器人的动力学模型.提出了基于模型预测的速度约束方法,通过限制每个轮子的运动速度,约束了机器人的实际运动速度.进一步,利用受约束的运动速度建立了动力学跟踪误差系统,提出了具有部分记忆信息的自适应迭代学习控制器设计方法,并验证了跟踪误差系统的稳定性.仿真对比分析和实验研究结果表明,文中提出的控制方法能抑制人机不确定性并使康复者在安全速度下完成步行训练. 相似文献
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为了提高康复步行训练器人的智能性和安全性,提出一种运动速度决策的康复训练机器人限时学习迭代控制方法,目的是抑制训练者位姿不确定性和人机速度不协调对系统安全性能的影响.建立具有系统不确定偏移量的康复步行训练机器人动力学模型,通过比较康复训练机器人当前的运动速度和训练者的实际步行速度,提出机器人运动速度的决策方法,从而使康复者在主动训练模式下实现人机速度协调运动;进一步,利用机器人决策的运动速度和动力学模型建立跟踪误差系统,提出有限学习时间的迭代控制方法,并基于Lyapunov理论验证跟踪误差系统的有限时间稳定性.仿真对比分析和实验结果表明,所提出的速度决策方法和跟踪控制方法能使人机系统协调地进行主动模式的康复训练. 相似文献
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输入力矩受限的机器人鲁棒自适应跟踪控制 总被引:2,自引:0,他引:2
在输入力矩受限的情况下, 提出一种全新的简单鲁棒自适应跟踪控制算法, 当参数的估计范围包含其真实值时, 证明了闭环系统的渐近稳定跟踪;当有干扰存在, 常规参数估计自适应控制算法不能实现稳定控制时, 本算法仍然使系统稳定, 在本算法中, 所估计的参数在跟踪控制律前馈项中表现为非线性, 这是区别于常规参数估计自适应算法的一个最重要特征. 因此本算法控制器的设计更有灵活性, 另一方面获得更好的控制品质和鲁棒性, 特别是对参数域估计误差即参数范围估计错误的强鲁棒性, 均为仿真算例所验证. 相似文献
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针对双足机器人的稳定行走,提出了一种预观控制的零力距点(ZMP)补偿步行模式在线生成方法。利用实际ZMP与目标ZMP之间的未来误差信息,基于预观控制计算机器人行走过程中质心的补偿量,事先调整质心轨迹来改变步态。最终使实际ZMP更好地跟踪目标值。12自由度的双足机器人动力学仿真验证了所提出方法的有效性,而且机器人能在一定程度不平整地面上实现稳定行走。 相似文献
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终端受限机器人系统轨道跟踪的新控制算法 总被引:1,自引:1,他引:0
研究一类终端受限机器人系统的控制问题,针对系统的轨道跟踪控制给出了一种新的学习控制算法.该算法克服了已有结果所存在的弱点,其跟踪学习控制的收敛过程既不依赖理想运动控制和理想力控制,也不依赖于相应的初始控制数据,大大改善了控制效果. 相似文献
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针对未开放力矩控制接口的一类封闭机器人系统, 提出一种基于外环速度补偿的确定学习控制方案. 该控制方案考虑机器人受到未知动力学影响, 且具有未知内环比例积分(Proportional-integral, PI)速度控制器. 首先, 利用宽度径向基函数(Radial basis function, RBF)神经网络对封闭机器人的内部未知动态进行逼近, 设计外环自适应神经网络速度控制指令. 在实现封闭机器人稳定控制的基础上, 结合确定学习理论证明了宽度RBF神经网络的学习能力, 提出基于确定学习的高精度速度控制指令. 该控制方案能够保证被控封闭机器人系统的所有信号最终一致有界且跟踪误差收敛于零的小邻域内. 在所提控制方案中, 通过引入外环补偿控制思想和宽度神经网络动态增量节点方式, 减小了设备计算负荷, 提高了速度控制下机器人的运动性能, 解决了市场上封闭机器人系统难以设计力矩控制的难题, 实现了不同工作任务下的高精度控制. 最后数值系统仿真结果和UR5机器人实验结果验证了该方案的有效性. 相似文献
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Redundant Input Safety Tracking for Omnidirectional Rehabilitative Training Walker with Control Constraints
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This study proposes a nonlinear safety tracking method based on redundant degrees of freedom with control constraints to protect against actuator faults that may occur in robotic rehabilitative walkers. A redundant input model with uniform actuator faults is constructed by separating the corresponding columns of the control matrix, and an adaptive robust control method is presented to deal with the separated term that is considered in relation to the extrinsic bounded interference that occurs on robotic walker systems. Based on the backstepping technique, an adjustable control law can be designed to maintain stability in terms of solving linear matrix inequality. The trajectory tracking error performance and the velocity tracking error performance are derived simultaneously. As an application, simulation results confirm the effectiveness of the proposed method and verify that the walker can provide safe sequential motions even when one wheel actuator fails. 相似文献
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针对一类二阶非线性不确定系统提出了一种新的控制方法,即带有灰色补偿的Backstepping控制,该方法分为两个阶段进行.第一阶段采用Backstepping控制方法进行控制,对不确定部分的模型参数进行估计.第二阶段经过N步参数估计之后,在上述控制律基础上,按估计参数加上补偿控制,构成带有灰色补偿的Baekstepping控制.该方法解决了非线性不确定系统的Backstepping控制问题.该方法不仅能精确估计出系统的不确定参数,而且经过补偿的控制器使系统的性能大为改善,并增强了系统的鲁棒性.仿真结果表明了该方法的有效性. 相似文献
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Jiajun Wang 《IEEE/CAA Journal of Automatica Sinica》2018,5(6):1128-1135
A novel speed-assigned method is applied to the position tracking control of switched reluctance motor (SRM). A speed control freedom can be drawn into the position control through speed assignment. Adaptive backstepping control is used to design the position controller for the SRM. The accuracy of position tracking of the SRM can be enhanced with speed assignment. A disturbance observer is further designed to enhance the estimation accuracy of the unknown load torque. Simulation results certify that the design scheme is right and effective. 相似文献
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上下肢康复训练器对偏瘫和肢体残障患者的治疗和康复有明显效果,所以研发上下肢康复训练器就显得尤为重要和急迫。康复训练器对患者治疗的功能实现主要由控制系统来完成,控制系统是康复训练器的核心。本文围绕控制系统的设计,对控制系统的搭建、人机交互界面设计、患者安全训练控制等方面进行阐述,为康复训练器整体设计奠定基础。 相似文献
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The present paper investigates stochastic modelling and a new nonlinear reliable tracking control method for a rehabilitative training walker. The stochastic model is constructed by considering random parameters. A new nonlinear tracking method against actuator fault is proposed based on redundant degree of freedom and a state feedback controller is designed by exploiting an adaptive control technique. It is proved that the mean square of the trajectory tracking error can be made arbitrarily small by choosing appropriate design parameters. As an application, simulation results confirm the effectiveness of the proposed method and verify that the walker with random parameters can provide safe sequential motion when one wheel actuator is at fault. 相似文献
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In this study, we propose a model and an output feedback tracking control for an omnidirectional rehabilitative training walker (ODW) with unmeasurable speed, incomplete measurements of position output, and random structural parameters. A stochastic model and an incomplete measurement model were proposed to describe the motion of an ODW subject to random structural parameters and to account for any incomplete data transmission phenomenon caused by possible sensor ageing or failures. A speed observer and a state observer were designed to estimate the unmeasurable speed and the incomplete measurements of position output. Moreover, a dynamic output feedback controller was constructed to ensure the exponential stability in mean square of the tracking error system. Furthermore, the results verify that the choice of appropriate design parameters can result in the mean square of the tracking error becoming arbitrarily small. A simulation example was provided to illustrate the effectiveness of the proposed design procedures. 相似文献
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This paper addresses the robust and accurate trajectory tracking problem for unmanned helicopters in the presence of model uncertainties and external disturbances. First, the helicopter's model is simplified to a six‐degrees‐of‐freedom rigid body augmented with a simplified rotor dynamic model, with the model uncertainties and the external disturbances being treated as lumped unknown disturbances. Second, a nonlinear disturbance observer is designed to estimate this lumped disturbance. Then, a backstepping controller with disturbance compensation is designed to ensure robust and highly trajectory tracking. After that, the theoretical analysis of the efficiency of the designed disturbance observer‐based backstepping controller (Backstepping+DO) is shown by the Lyapunov theory. Finally, simulation results and conclusions are presented and discussed. 相似文献