This brief proposes a disturbance rejection control strategy for attitude tracking of an aircraft with both internal uncertainties and external disturbances. The proposed consists robust observer (DOB) nonlinear feedback controller. Specifically, DOB is to compensate the uncertain rotational dynamics into nominal plant, based on which controller implemented desired performance. We first divide practical part, disturbances, equivalent Then, property disturbances explored stability analysis. A...

This paper proposes a method for designing disturbance observer (DOB) in vibration suppression control of two-inertia system. The key to system is eliminating the effect modes plant. For this purpose, feedback controller designed cancel stable However, cancellation fails due model error from parameter variations. In paper, DOB employed compensate Q-filter with following specifications: optimal performance restricted cutoff frequency; robust stability closed-loop against modeling between...

This brief proposes a method for designing disturbance observer (DOB) to decouple joint interactions in robot dynamics with nonlinearity. The traditional DOB based on filter design theory has limited performance since the cut-off frequency of its Q-filter is only tunable parameter deal suppression and model uncertainty. In this brief, robust optimal developed DOB, which can achieve suppressing by systematically shaping Q-filter. Simulation results application two-link manipulator flexible...

Recent years have witnessed the popularity of integrating Siamese network into RGBT tracking for fast-tracking. However, these trackers mostly utilize feature information last output layer and ignore benefits multi-layer information. In addition, they often adopt feature-level fusion different modalities but fail to explore strength decision-level fusion, which may easily decrease their flexibility independence. this paper, a novel attention aggregation on decision level is proposed robust...

This paper addresses the calibration-free robotic eye-hand coordination in a way other than conventional image Jacobian matrix approach that has been studied extensively literature. A nonlinear mapping rather linear used between space and control is proposed. regarded as system's unmodeled dynamics expressed system state equations. An extended observer designed first to estimate well external disturbance of system. With estimation results compensation, controller based on state-error...

Reinforcement learning (RL) and imitation (IL), especially equipped with deep neural networks, have been widely studied for autonomous robotic skill acquisition control tasks. However, these methods their extensions require extensive environmental interactions during training, which greatly prevents them from being applied to real-world robots. To alleviate this problem, we present an efficient model-free off-policy actor-critic algorithm continuous control, by fusing the task reward a...

A novel disturbance observer (DOB)-based switching control strategy is proposed to achieve fast, smooth, and accurate performance in the presence of both external disturbances internal uncertainties. This methodology consists two DOBs designed with different frequency responses, mechanism meticulously schedule DOBs. To further study DOB-based control, a model transformation introduced alleviate conservatism robust stability closed-loop system. Thus, H <sub...

This paper studies the visual servoing problem with sensory feedback from uncalibrated stereo cameras. The linear image Jacobian matrix is used to describe spatial and temporary approximation of differential movement relation between space robotic workspace. We suggest construct an instrumental dynamic system state variables formed elements matrix. Thus a Kalman-Bucy filter estimate constructed online, which robust noise external disturbances. A 3D tracking task by robot manipulator cameras...

On the basis of classical computed torque control method, a composite nonlinear feedback (CNF) design method for robot manipulators with bounded torques is presented. The resulting controller consists two loops. inner loop full compensation dynamics and outer CNF stabilisation performance enhancement. Stability analysis carried out an estimate domain attraction specified in presence actuator saturation. In addition to guaranteed stability properties, takes advantage varying damping ratio...

Summary The disturbance observer (DOB)‐based controller is widely used to estimate and suppress in motion control system. Because the low‐pass filter (Q‐filter) DOB decides performances of suppression, noise rejection, robust stability against system uncertainties, design Q‐filter principal task construction. This paper presents a systematic scheme for based on H ∞ norm optimization. Cost function optimization proposed by considering performance relative order condition Q‐filter....

This paper proposes a general motion planning and coordination strategy for robot systems. The representation space (RS) of system is constructed to describe the distributions attributes. reachable area in RS, denoting attribute set that can be of, indicates system's ability accomplish tasks. Moreover, it also describes influences internal external constraints on capability. Task realization transformed finding trajectory RS attributes transit along under constraints. Meanwhile, realizable...

A great many efforts have been devoted to reproducing a reference image for Chinese calligraphy with robot. However, there exist modeling errors in mapping from the presentation of brush trajectories. In this paper, closed-loop system is established decrease effects brought by and optimize aesthetics. strategy robotic newly proposed based on aesthetics evaluation, which characterized three indexes. Each stroke planned online achieve best effect whole work. constraint optimization problem...

A telepresence system enables a user in local environment to maneuver remote or virtual space through robotic operator (agent). In order ensure high degree of realism, it is critical that the has ability control agent's movement user's own locomotion. The required motion agent determined according its and specific task perform. usually different from terms shapes dimensions. mapping needed similarity paths two environments. particular, terminal position after segment also an important...

Recently have testified the superior tracking ability of Transformer in RGBT for its global and dynamic modeling property. However, these Transformer-based trackers lack attention to primary feature information are susceptible interference from background information. In addition, they often either focus on shared modality or specific information, but fail adequately explore potential two patterns together. To address issues, a sparse trifurcate aggregation network is proposed this paper...