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移动机器人在复杂地形条件下面临环境和模型不确定性的挑战, 例如草地、陡坡等环境会对移动机器人的高精度控制造成影响. 本文提出了一种基于高斯过程建模的移动机器人学习预测控制方法, 能够对环境和模型不确定性进行实时的建模和预测, 并将该模型用于最优控制策略的学习中, 完成在模型和环境不确定下的机器人运动控制. 该方法利用高斯过程回归对环境和模型不确定性进行建模, 并结合系统运动学方程得到误差状态模型, 并将该模型用于滚动时域强化学习中, 通过迭代优化学习最优控制策略. 最后, 针对移动机器人在椭圆和8字形轨迹上的横向跟踪控制问题, 进行了仿真实验, 并与非线性模型预测控制进行比较. 结果表明, 本文提出的方法能够有效提升复杂地形条件下控制器的控制性能, 在性能指标上相比未采用高斯过程建模的滚动时域强化学习方法提高20%, 比非线性模型预测控制方法提高36%, 验证了所提方法的有效性和优越性 相似文献
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受侧风影响,高速行驶的车辆易偏离预定行驶轨迹,增加驾驶员“误操作”的风险,存在较大安全隐患,为此,该文开展了车辆侧风稳定性主动控制研究。该研究通过建立附加气动力作用的三自由度整车动力学模型,设计主动前轮转向的车辆侧风稳定性模型预测控制器,并搭建 Simulink-CarSim 联合仿真平台进行验证分析。结果表明,在单向侧风工况和交变侧风工况下,带侧风稳定控制的车辆最大侧向偏移量为 0.01 m,远低于无控制时的偏移量;横摆角速度平台值保持在“0”左右,横摆角速度峰值最高降低了 80%,极大地提高了车辆的侧风稳定性。 相似文献
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为了提升不同运行工况下的路面状态识别精度及主动悬架平顺性控制性能,提出一种基于ResNeSt网络路面状态识别的主动悬架模型预测控制(MPC)方法.首先,搭建基于多路径分散注意力思想的ResNeSt网络架构,建立面向主动悬架实时控制的路面状态识别算法,采用交叉熵目标损失函数和AdamW梯度下降算法进行网络训练以及测试实验验证;然后,在此基础上设计基于路面状态识别的主动悬架MPC控制算法,根据离散状态空间方程推导悬架系统预测模型,以悬架预测输出和控制力输入为性能指标建立目标函数,并考虑不同路面的控制策略确定加权矩阵取值,在系统约束条件下,将MPC目标函数转化为二次最优规划问题的求解;最后,将所提出控制算法与被动悬架、LQG控制进行对比仿真分析,结果表明:ResNeSt网络可以快速准确地识别多种路面状态,所提出控制算法能够根据路面状态对悬架进行实时瞬态主动控制,簧载质量加速度、悬架动挠度和轮胎动载荷的均方根值平均值相比LQG控制分别降低36.56%、32.99%和36.28%. 相似文献
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控制系统中存在的不确定性为其性能优化带来诸多问题.自适应控制和鲁棒控制是针对系统存在的不确定性而采取的不同设计策略;前者没有充分考虑系统的未建模动态,而后者往往是针对不确定的最大界而设计,具有较强的保守性.本文试图将自适应控制和鲁棒控制的策略相结合,提出了一种在模型预测控制中利用未来不确定信息的对偶自适应模型预测控制策略.该策略将系统中由未建模动态引起的不确定性参数化表达,并为其设定边界约束,作为优化问题中新的约束,在优化控制目标的同时减小系统不确定性对控制的影响.仿真结果表明,本文提出的算法较传统自适应模型预测控制算法,对于系统存在的不确定性由于在迭代过程中采用参数化描述,得到了更好的系统性能,且具有更好的收敛性. 相似文献
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基于不变集理论, 拓展了Chiscil等人提出的约束不变预测控制方法(ICPC), 提出了一种适用于带约束多面体不确定线性系统的预测控制的框架. 其关键在于为针对标称系统设计的在线优化问题附加适当的额外的鲁棒可行约束. 若优化问题在初始阶段可行, 则此约束可保证在线优化问题始终可行, 从而保证了实际系统中约束条件的始终满足. 同时提出了闭环系统鲁棒稳定的一个充分条件, 可为成本函数的选择提供指导以保证预测控制器的鲁棒镇定. 相似文献
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徐晓冰;孙伟;赵龙;李宾宾;陈艺;王鑫 《自动化技术与应用》2024,(10):22-25+34
以需求响应为核心进行配电网负荷控制优化时,节能百分比较低。因此,提出基于高斯过程回归的主动配电网负荷控制优化方法。依托于随机森林算法,判断所有输入变量的重要性,明确主动配电网负荷影响变量。运用高斯过程回归原理,应用负荷预测算法,准确得出主动配电网需求侧未来一段时间内的负荷要求。在此基础上,以直接负荷控制为核心,建立负荷控制协调优化模型,再应用遗传算法求解最优负荷控制优化方案。算例分析结果表明:所提优化方法的节能百分比达到6.23%,说明该方法达到了节能的目的。 相似文献
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分布式模型预测控制(Distributed model predictive control, DMPC)是一类用于多输入多输出的大规模系统的控制方式.每个智能体通过相互协作完成整个系统的控制. 已有的分布式预测控制算法可以划分为迭代式算法和非迭代算法:迭代算法在迭代到收敛情况下,具有集中式预测控制(Centralized model predictive control, CMPC)算法的性能,但迭 代次数过多,子系统间通信量大;非迭代算法不需要迭代,但性能有一定损失.本文提出了一种基于串联结构的非迭代分布式预测控 制算法.本文算法在串联结构系统中可以有效减少计算量,并结合氧化铝碳分解(Alumina continuous carbonation decomposition process, ACCDP)这一串联过程,通过仿真验证了算 法的有效性;同时分析了算法运用在串联结构下的性能并证明了其稳定性. 相似文献
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A latent variable iterative learning model predictive control (LV-ILMPC) method is presented for trajectory tracking in batch processes. Different from the iterative learning model predictive control (ILMPC) model built from the original variable space, LV-ILMPC develops a latent variable model based on dynamic partial least squares (DyPLS) to capture the dominant features of each batch. In each latent variable space, we use a state–space model to describe the dynamic characteristics of the internal model, and an LV-ILMPC controller is designed. Each LV-ILMPC controller tracks the set points of the current batch projection in the corresponding latent variable space, and the optimal control law is determined and the persistent process disturbances is rejected along both time and batch horizons. The proposed LV-ILMPC formulation is based on general LV-MPC and incorporates an iterative learning function into LV-MPC. In addition, the real physical input that drives the process can be reconstructed from the latent variable space. Therefore, this algorithm is particularly suitable for multiple-input, multiple-output (MIMO) systems with strong coupling and serious collinearity. Three studies are used to illustrate the effectiveness of the proposed LV-ILMPC . 相似文献
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This paper proposes a hybrid Gaussian process (GP) approach to robust economic model predictive control under unknown future disturbances in order to reduce the conservatism of the controller. The proposed hybrid GP is a combination of two well-known methods, namely, kernel composition and nonlinear auto-regressive. A switching mechanism is employed to select one of these methods for disturbance prediction after analyzing the prediction outcomes. The hybrid GP is intended to detect not only patterns but also unexpected behaviors in the unknown disturbances by using past disturbance measurements. A novel forgetting factor concept is also utilized in the hybrid GP, giving less weight to older measurements, in order to increase prediction accuracy based on recent disturbances values. The detected disturbance information is used to reduce prediction uncertainty in economic model predictive controllers systematically. The simulation results show that the proposed method can improve the overall performance of an economic model predictive controller compared to other GP-based methods in cases when disturbances have discernible patterns. 相似文献
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A dual closed‐loop tracking control is proposed for a wheeled mobile robot based on active disturbance rejection control (ADRC) and model predictive control (MPC). In the inner loop system, the ADRC scheme with an extended state observer (ESO) is proposed to estimate and compensate external disturbances. In the outer loop system, the MPC strategy is developed to generate a desired velocity for the inner loop dynamic system subject to a diamond‐shaped input constraint. Both effectiveness and stability analysis are given for the ESO and the dual closed‐loop system, respectively. Simulation results demonstrate the performances of the proposed control scheme. 相似文献
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为了降低群体动画中生成大量自然而又相似的人体运动的难度和复杂性,研究了一种基于学习的群体动画生成技术。该技术首先通过建立基于高斯过程隐变量模型和隐空间动态模型的运动姿势学习模型,将高维运动姿势映射到低维隐空间中,并在低维隐空间对相邻姿势的动态演化进行建模;然后通过对已有运动数据的学习来获得组成该运动的姿势的概率分布,再通过隐空间中的动态预测和Hybrid Monte Carlo采样来得到符合给定概率分布的隐轨迹;最后通过姿势重构来得到与原运动非常相似但又不同的一系列自然的运动,以产生群体动画,从而避开了传统的基于几何和物理约束的逆运动方法固有的困难和复杂性。 相似文献
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针对影响台风最大风速的输入变量较多以及输入变量与输出变量之间的非线性变化特点,首先计算各个输入变量与输出变量间的互信息,这些互信息间接地反映了各个输入变量与输出变量间的相关性;然后根据t检验法确定一个阈值,对于互信息小于阈值的输入变量作不相关变量处理,筛选出最佳的模型输入变量;最后采用高斯过程回归模型对筛选后的样本集进行拟合,在贝叶斯非参数建模的框架下,确定高斯过程回归模型的协方差函数.仿真结果表明,所得高斯过程模型能够满足绝对误差的预定要求,且具有较大的实用价值. 相似文献
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Pneumatic muscle actuators (PMAs) are compliant and suitable for robotic devices that have been shown to be effective in assisting patients with neurologic injuries, such as strokes, spinal cord injuries, etc., to accomplish rehabilitation tasks. However, because PMAs have nonlinearities, hysteresis, and uncertainties, etc., complex mechanisms are rarely involved in the study of PMA-driven robotic systems. In this paper, we use nonlinear model predictive control (NMPC) and an extension of the echo state network called an echo state Gaussian process (ESGP) to design a tracking controller for a PMA-driven lower limb exoskeleton. The dynamics of the system include the PMA actuation and mechanism of the leg orthoses; thus, the system is represented by two nonlinear uncertain subsystems. To facilitate the design of the controller, joint angles of leg orthoses are forecasted based on the universal approximation ability of the ESGP. A gradient descent algorithm is employed to solve the optimization problem and generate the control signal. The stability of the closed-loop system is guaranteed when the ESGP is capable of approximating system dynamics. Simulations and experiments are conducted to verify the approximation ability of the ESGP and achieve gait pattern training with four healthy subjects. 相似文献
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Importance of batch processes has grown recently with the increasing economic competition that has pushed the manufacturing industries to pursue small quantity production of diverse high value-added products. Accordingly, systems engineering research on advanced control and optimization of batch processes has proliferated. In this paper, we examine the potentials of ‘iterative learning control (ILC)’ as a framework for industrial batch process control and optimization. First, various ILC rules are reviewed to provide a historical perspective. Next it is shown how the concept of ILC can be fused with model predictive control (MPC) to build an integrated end product and transient profile control technique for industrial chemical batch processes. Possible extensions and modifications of the technique are also presented along with some numerical illustrations. Finally, other related techniques are introduced to note the similarities and contemplate the opportunities for synergistic integration with the current ILC framework. 相似文献
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在烟草行业的烘丝过程中,烟丝的出口水分作为被控对象常常具有大滞后与强非线性的特性,且在工艺流程中通常存在干扰因素;当前,这一过程中大多仍采用传统PID控制器,存在响应稳态误差大、响应时间长等问题,进而影响烟丝的最终品质;针对这一情况,引入组合积分控制器替代传统PID控制器在烘丝过程中的作用;同时引入双重控制,并与组合积分控制器相结合;针对控制对象进行的仿真实验结果表明,这一新型控制策略在烘丝过程出口水分的控制效果上明显优于传统PID控制器,稳态误差较小且响应迅速,证明了组合积分控制器运用在双重控制系统中时具有优异的动态性能与鲁棒性;最后,这一新型双重控制算法已成功应用到烟草行业烘丝过程的水分控制上。 相似文献