共查询到19条相似文献,搜索用时 46 毫秒
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机械臂的动力学模型通常包含一定的结构不确定性,并受到外界未知干扰的影响。针对现有模型的不确定性特点,提出了一种基于非线性扰动观测器的自适应反演滑模控制方法,解决机械臂的轨迹跟踪控制问题。对于外界干扰,利用非线性扰动观测器进行观测补偿,无需上界先验知识;对于结构不确定性,引入反演滑模控制,同时设计自适应律,保证闭环系统的稳定性并增强系统的动态适应性。仿真结果证明,所提出的方法可以有效克服系统不确定性,降低控制输入信号的抖振,最终实现期望轨迹的快速精确跟踪。 相似文献
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多机械臂的精准协同控制已成为当前机器人领域的研究难点,为实现双机械臂精准控制,通过建立双机械臂动力学模型,采用时间延时估计简化机械臂动力学模型,在保证控制系统稳定性的前提下,引入自适应模糊滑模控制器实现对估计误差的修正和补偿,设计基于时间延时估计和自适应模糊滑模控制的双机械臂协同阻抗控制器,实现双机械臂协同操作的末端轨迹控制以及接触力精准控制.最后,将该控制器应用于两台六自由度机械臂仿真平台,实现双臂夹取和搬运同一目标物体的操作,通过与其他控制器进行对比实验,表明所设计的控制器具有响应快、无抖震、精度高的特点. 相似文献
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针对机器人系统滑模控制器设计存在的抖振问题,提出了一种新型的具有可变滑模增益的控制器设计方案。在传统滑模控制器设计的基础上,该控制方案的创新之处在于所设计控制器的开关增益可实现动态自适应调整。采用径向基函数神经网络(radialbasis function neural network, RBFNN),使开关增益随关节参数动态改变,以适应系统的未建模动态及未知扰动。通过加入适当的自适应控制算法,有效地抑制逼近误差及外部扰动。并且,通过李雅普诺夫方法证明了系统的轨迹跟踪误差可渐近收敛到0。最后,仿真结果表明,所设计的方案降低了系统抖振,同时可有效地提高跟踪精度。 相似文献
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针对传统滑模和传统干扰观测器在机械臂关节位置跟踪中存在的控制输入抖振、需要测量加速度项、应用模型受限等问题,提出一种改进非线性干扰观测器的机械臂自适应反演滑模控制算法。首先,设计改进的非线性干扰观测器进行在线测试,在滑模控制律中加入干扰估计值对可观测的干扰进行补偿;然后选择合适的设计参数,使观测误差指数型收敛;其次,引入反演自适应控制律,对不可观测的干扰进行估计,进一步改善控制系统的跟踪性能;最后,利用李雅普诺夫函数验证了闭环系统的渐近稳定性,并将其应用于机械臂关节位置跟踪。实验结果表明,与传统滑模算法比较,所提控制算法不但加快了系统的响应速度,而且能有效地削弱系统抖振、避免测量加速度项并扩大应用模型使用范围。 相似文献
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针对机器人跟踪控制问题,设计了一种新型的动态滑模控制器,采用反演(backstepping)方法设计一种新的切换函数,将不连续项转移到了控制的一阶导数中,得到了输入的平滑性的动态滑模控制律。该控制律能保证轨迹跟踪误差的快速收敛性和参数不确定的鲁棒性,仿真实例验证了该控制算法的有效性。 相似文献
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Fuzzy sliding mode control for a robot manipulator 总被引:1,自引:0,他引:1
This work presents the design of a robust control system using a sliding mode controller that incorporates a fuzzy control
scheme. The presented control law superposes a sliding mode controller and a fuzzy logic controller. A fuzzy tuning scheme
is employed to improve the performance of the control system. The proposed fuzzy sliding mode control (FSMC) scheme utilizes
the complementary cooperation of the traditional sliding mode control (SMC) and the fuzzy logic control (FLC). In other words,
the proposed control scheme has the advantages which it can guarantee the stability in the sense of Lyapunov function theory
and can ameliorate the tracking errors, compared with the FLC and SMC, respectively. Simulation results for the trajectory
tracking control of a two-link robot manipulator are presented to show the feasibility and robustness of the proposed control
scheme.
This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January
31–February 2, 2008 相似文献
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This paper presents the design, and validation of a new adaptive control system based on quasi-time delay estimation (Q-TDE) augmented with new integral second-order terminal sliding mode control (ISOTSMC) for a manipulator robot with unknown dynamic uncertainty and disturbances. Contrary to the conventional TDE, the proposed Q-TDE becomes sufficient to invoke a fixed artificial time delay and utilize the past data only of the control input to approximate the unknown system''s dynamic uncertainties. The incorporating of new adaptive reaching law with ISOTSMC augmented with Q-TDE policy ensures the continuous performance tracking of the robot manipulator''s trajectories using output feedback. This combination may achieve high performance with a significant chattering reducing procedure. By utilizing the Lyapunov function theory, it can be demonstrated that the robot system is stable and all signals in closed-loop are converging in finite time. Consequently, Simulation and comparative studies with two degrees of freedom robot manipulator were carried out to validate the effectiveness of the designed control scheme. 相似文献
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In this paper, an adaptive nonsingular fast terminal sliding mode control (ANFTSMC) is proposed for underwater manipulator robotics with asymmetric actuator saturations and unknown time-varying (TV) external disturbances. Firstly, the nonsingular fast terminal sliding mode (NFTSM) control scheme is conducted for the underwater manipulator robotics, which guarantees the boundedness of all the signals in the control system. Secondly, the adaptive method and the smooth hyperbolic tangent (tanh) function are introduced to address the unknown TV external disturbances and the input saturation errors. Thus the prior knowledge about the upper bounds of the system uncertainties is not needed in this paper. To deal with the nonlinear asymmetric input saturation issue, a Gaussian error function is employed in the asymmetric saturation module so that the discontinuous input signals can be transformed into smooth forms. Thirdly, the rigorous mathematical verification is conducted to demonstrate the stability and finite-time convergence of the closed-loop control system via the Lyapunov theory. Finally, numerical simulations are performed on a two-link underwater manipulator robotic system to illustrate the effectiveness of the proposed controller. 相似文献
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A continuous sliding mode control with moving sliding surface for nonlinear systems of arbitrary order is presented in this paper. The sliding surface is moved repetitively toward the target sliding surface in order to ensure that the system trajectory is close to the actual surface during the whole control process. The parameters of sliding mode control are tuned by a fuzzy logic. The proposed procedure reduces the time when the system operates in the approaching phase during which the control performance is deteriorated since the system is more susceptible to external disturbances and model uncertainties. The effectiveness of the presented approach is demonstrated on a control of a flexible robot manipulator arm. 相似文献
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ABSTRACTThis editorial article gives a short introduction to Special Issue of International Journal of Control on Adaptive Sliding Mode Control and Observation. 相似文献
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Gian Paolo Incremona Michele Cucuzzella Antonella Ferrara 《International journal of control》2016,89(9):1849-1867
ABSTRACTThis paper deals with the design of adaptive suboptimal second-order sliding mode (ASSOSM) control laws for grid-connected microgrids. Due to the presence of the inverter, of unpredicted load changes, of switching among different renewable energy sources, and of electrical parameters variations, the microgrid model is usually affected by uncertain terms which are bounded, but with unknown upper bounds. To theoretically frame the control problem, the class of second-order systems in Brunovsky canonical form, characterised by the presence of matched uncertain terms with unknown bounds, is first considered. Four adaptive strategies are designed, analysed and compared to select the most effective ones to be applied to the microgrid case study. In the first two strategies, the control amplitude is continuously adjusted, so as to arrive at dominating the effect of the uncertainty on the controlled system. When a suitable control amplitude is attained, the origin of the state space of the auxiliary system becomes attractive. In the other two strategies, a suitable blend between two components, one mainly working during the reaching phase, the other being the predominant one in a vicinity of the sliding manifold, is generated, so as to reduce the control amplitude in steady state. The microgrid system in a grid-connected operation mode, controlled via the selected ASSOSM control strategies, exhibits appreciable stability properties, as proved theoretically and shown in simulation. 相似文献
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《Engineering Applications of Artificial Intelligence》2005,18(4):451-459
The adaptive fuzzy sliding mode control is applied to the attitude stabilization of flexible satellite. The detailed design procedure of the fuzzy sliding mode control system is presented. The adaptive fuzzy control is utilized to approach the equivalent control of sliding mode control and the adaptive law is derived. The hitting control, which guarantees the stability of the control system, is developed. In order to attenuate the chattering phenomena, fuzzy rules are employed to smooth the hitting control. Simulation results show that precise attitude control is accomplished based on the proposed method. 相似文献