Hysteresis has posed significant challenges to the modeling and control of flexible endoscopic robots, which impedes the advancement of automated endoscopic operation. Despite numerous hysteresis modeling approaches a...
详细信息
ISBN:
(纸本)9798350377712;9798350377705
Hysteresis has posed significant challenges to the modeling and control of flexible endoscopic robots, which impedes the advancement of automated endoscopic operation. Despite numerous hysteresis modeling approaches aimed at improving accuracy, there are still several unresolved issues, such as inappropriate model selection and non-ideal assumption of noise. Focusing on these challenges, a novel reinforcement active modeling (RAM) scheme is proposed in this paper. By incorporating reinforcement learning, this method augments an Extended Kalman Filter (EKF)-based active modeling strategy, which improves the insensitivity and generalization ability to non-Gaussian noise that is not introduced in training. Finally, a series of comparative experiments are conducted on the self-built flexible endoscopic robot to validate the improvement achieved by the proposed scheme. Compared with some widely-applied methods, the proposed scheme achieved at least 63.8% improvement in the root mean square error (RMSE) in modeling accuracy under Gaussian noise conditions, and at least 36.5% improvement in RMSE under Poisson noise conditions.
This paper considers a differential game approach to the predecessor-following vehicle platoon control problem without and with collision avoidance. In this approach, each vehicle tries to minimize the performance ind...
详细信息
ISBN:
(纸本)9798350399462
This paper considers a differential game approach to the predecessor-following vehicle platoon control problem without and with collision avoidance. In this approach, each vehicle tries to minimize the performance index (PI) of its control objective, which is reaching consensual velocity with the predecessor vehicle while maintaining a small inter-vehicle distance from it. Two differential games were formulated. The differential game problem for platoon control without collision avoidance is solved for the open-loop Nash equilibrium and its associated state trajectories. The second differential game problem for platoon control with collision avoidance has a non-quadratic PI, which poses a greater challenge to obtaining its open-loop Nash equilibrium. Since the exact solution is unavailable, we propose an estimated Nash strategy approach that is greatly simplified for implementation. An illustrative example of a vehicle platoon control problem was solved under both the without and with collision avoidance scenarios. The results showed the effectiveness of the models and their solutions for both scenarios.
Cybersecurity-enabled smart renewable energy system security requires a multifaceted strategy that includes proactive risk assessment, strong defenses, stakeholder cooperation, and the combination of cutting-edge tech...
详细信息
ISBN:
(纸本)9798350361261;9798350361278
Cybersecurity-enabled smart renewable energy system security requires a multifaceted strategy that includes proactive risk assessment, strong defenses, stakeholder cooperation, and the combination of cutting-edge technology such as Artificial Intelligence (AI) and blockchain. To safeguard vital infrastructure and guarantee a continuous supply of energy, defense-in-depth strategies such as encryption protocols, and access controls can be put into place in conjunction with cybersecurity awareness campaigns and regular security audits. In the face of changing cyber threats, these initiatives are crucial to protect data privacy and system resilience for the development of sustainable energy. This study aims to provide important insights into current practices, identify areas for improvement, and provide insight for further studies and regulations intended to improve the energy infrastructure's security and resilience in the digital era.
In this work, a novel online model-free controller for an underactuated dirigible is developed based on reinforcement learning and optimal control theory. A reinforcement learning structure is used while overcoming th...
详细信息
ISBN:
(纸本)9781665491907
In this work, a novel online model-free controller for an underactuated dirigible is developed based on reinforcement learning and optimal control theory. A reinforcement learning structure is used while overcoming the dependence of the value function on future values by introducing a neural network that is adapted using input-output data. The suboptimal critic neural network is structured such that optimality is guaranteed over the interval from which the data is valid. The system performance is validated using a highly realistic physics engine, Gazebo, with the robot operating system (ROS) interface and the results are compared to the performance of a model-based controller specifically designed to control the airship model. It is emphasized that the proposed formulation does not leverage any knowledge of vehicle dynamics and thus is considered a vehicle agnostic control strategy.
The traditional construction management model has been unable to meet the high requirements of safety, quality, efficiency, etc., coupled with the development of information technology such as BIM, GIS, IoT, etc., the...
详细信息
Assembly processes involving humans and robots are challenging scenarios because the individual activities and access to shared workspace have to be coordinated. Fixed robot programs leave no room to diverge from a fi...
详细信息
ISBN:
(纸本)9798350377712;9798350377705
Assembly processes involving humans and robots are challenging scenarios because the individual activities and access to shared workspace have to be coordinated. Fixed robot programs leave no room to diverge from a fixed protocol. Working on such a process can be stressful for the user and lead to ineffective behavior or failure. We propose a novel approach of online constraint-based scheduling in a reactive execution control framework facilitating behavior trees called CoBOS. This allows the robot to adapt to uncertain events such as delayed activity completions and activity selection (by the human). The user will experience less stress as the robotic coworkers adapt their behavior to best complement the humanselected activities to complete the common task. In addition to the improved working conditions, our algorithm leads to increased efficiency, even in highly uncertain scenarios. We evaluate our algorithm using a probabilistic simulation study with 56000 experiments. We outperform all other compared methods by a margin of 4- 10%. Initial real robot experiments using a Franka Emika Panda robot and human tracking based on HTC Vive VR gloves look promising.
Most land-air amphibious UAVs feature a four-wheel design that limits their adaptability in narrow and uneven spaces. This study proposes the rotor flywheel as a new land-air design that integrates a one-wheel structu...
详细信息
ISBN:
(纸本)9781665491907
Most land-air amphibious UAVs feature a four-wheel design that limits their adaptability in narrow and uneven spaces. This study proposes the rotor flywheel as a new land-air design that integrates a one-wheel structure and eight-rotor wings for more flexible motion. The dynamics model is then conducted with the Kane method, finding two power-saving self-balance state while rolling. Its controller design highlights the multi-input decoupling approach utilizing feedback, along with the dynamic model-based component to enable efficient control of its intricate operations. Results of simulations and experimental tests have validated the stability and adaptability of the mode-switching and rolling of the robot in ground motion.
Time-series data prediction aims to predict future data according to previous data. Following the temporal correlation of data, the data can be forecasted via recurrent network, considering the neighboring data. By le...
详细信息
This paper investigates the performance of an intelligent reflecting surface (IRS)-assisted underwater optical wireless communication (UOWC) system in considering oceanic propagation loss, oceanic turbulence, and poin...
详细信息
ISBN:
(纸本)9798350336672
This paper investigates the performance of an intelligent reflecting surface (IRS)-assisted underwater optical wireless communication (UOWC) system in considering oceanic propagation loss, oceanic turbulence, and pointing errors. Pointing errors induced by IRS vibration is the main factor that causes the performance degradation of IRS-assisted UOWC systems. Unlike previous works that employed zero boresight pointing error model for the performance analysis of UOWC systems, in this study, we develop a nonzero boresight pointing error model. In addition, we derive the approximation formula for the comprehensive channel model that combines three separate models including the propagation loss model, log-normal oceanic turbulence model, and the nonzero boresight pointing error model. The outcomes of this study reveal that the vibration of an IRS-installed buoy/ship severely impacts the system outage performance. Insightful discussions based on the numerical results are useful for the practical system design of the IRSassisted UOWC system.
This study presents a Takagi-Sugeno (T-S) fuzzy logic-based modeling technique for a Mecanum Wheeled Mobile Robot (MWMR). T-S systems are well-suited for handling the inherent nonlinearities and undisclosed subsystems...
详细信息
ISBN:
(纸本)9798331517939;9788993215380
This study presents a Takagi-Sugeno (T-S) fuzzy logic-based modeling technique for a Mecanum Wheeled Mobile Robot (MWMR). T-S systems are well-suited for handling the inherent nonlinearities and undisclosed subsystems in the MWMR. A Genetic Algorithm (GA) is employed to optimize the T-S parameters so that the physical model can be perfectly obtained. Notably, without requiring an explicit description of the complete MWMR dynamics, the GA successfully converges to optimal T-S parameters within 200 generations. The resulting T-S model exhibits a high level of accuracy, achieving aMean Squared Error (MSE) of 0.015 when compared to the realMWMRsystem's velocity response.
暂无评论