Sliding mode control strategy of 3-UPS/S shipborne stable platform with LSTM neural network prediction

Tian, Wenxi; Zhang, Xiangpeng; Lv, Dongpo; Wang, Lina; Liu, Qi

doi:10.1016/j.oceaneng.2022.112497

Cited by 8 publications

(3 citation statements)

References 26 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Applying the inverse kinematic model, the leg motion of the robot was studied, and then using the leg motion through the simulation of the workspace of the robot, it was shown that the robot endeffector was able to follow a prescribed task. Tian et al [16] used 3-UPS/S as a shipborne stable platform to compensate ship orientation fluctuation and isolated the influence of wind and waves on shipborne equipment. Hence, an efficient and accurate control strategy was developed for this purpose in their study.…”

Section: Related Workmentioning

confidence: 99%

A 3UPS/S Spherical Parallel Manipulator Designed for Robot-Assisted Hand Rehabilitation after Stroke

Valayil,

Tanev

2024

Applied Sciences

View full text Add to dashboard Cite

Hand dysfunction is a common symptom in stroke patients. This paper presents a robotic device which assists the rehabilitation process in order to reduce the need of physical therapy, i.e., a 3UPS/S parallel robotic device is employed for repetitive robot-assisted rehabilitation. Euler angle representation was used to solve the robot’s inverse kinematics. The robot’s joint space and rotational workspace were determined for two scenarios. In the first scenario, the workspace was obtained considering the actuator’s stroke limitations, while in the second scenario, the workspace was determined by adding a second condition, i.e., the range of motion of the spherical joints. Singularity analysis was performed using the geometric algebra approach. The robot was manufactured using additive manufacturing technology. The solution of the inverse kinematic problem was employed to control the robot. The robot can perform a full range of motion during wrist ulnar deviation and radial deviation motions, with the exception of limited wrist flexion and extension motions. The robot has singular configurations within its workspace. Although the spherical joints have roles in reducing the workspace, the primary causes are actuator selection, radii of the base and moving platforms, and the length of the central leg. These factors can be considered to improve the workspace. Singularity can be avoided by carefully selecting the rotation of the moving platform about the Z-axis and avoiding same leg lengths.

show abstract

Section: Related Workmentioning

confidence: 99%

A 3UPS/S Spherical Parallel Manipulator Designed for Robot-Assisted Hand Rehabilitation after Stroke

Valayil,

Tanev

2024

Applied Sciences

View full text Add to dashboard Cite

show abstract

“…By establishing a forward and inverse kinematic model, a group of electric cylinders was controlled by real-time attitude feedback [19]. A sliding mode controller based on the kinematic model of the mechanism was designed for a 3-UPS/S parallel stable platform [20]. The controller took the LSTM-based ship orientation prediction as the input.…”

Section: Introductionmentioning

confidence: 99%

An Offshore Self-Stabilized System Based on Motion Prediction and Compensation Control

Liu

Yuan

Xiao

et al. 2023

JMSE

View full text Add to dashboard Cite

The swaying motion of ships can always be generated due to the influence of complex sea conditions. A novel offshore Self-Stabilized system based on motion prediction and compensation control was studied. Firstly, an autoregressive model of ship motion exposed to various sea conditions was established, and the parameters of the model were initialized and updated by offline and online learning historical data. Using the autoregressive model with the acquired parameters, the prediction of the ship’s motion was achieved. Then, a Self-Stabilized system platform composed of six electric cylinders in parallel was designed, and the corresponding inverse kinematics were established. The corresponding controller using the result of motion prediction as the input was also proposed to counteract the extra motion variables of the ship. Various experiments, by simulating different sea conditions, can be carried out. The results show that the average error of the motion prediction was less than 1%. The maximum error of the self-stabilizing control was 1.6°, and the average error was stable within 0.7°. The Self-Stabilized system was able to effectively compensate for the rocking motion of ships affected by waves, which was of great significance for improving the maritime safety guarantee and the intelligent level of shipborne equipment.

show abstract

“…However, in the process of prediction, the selection of the algorithm model is essential. Various algorithms such as neural network, support vector machine (SVM), support vector regression (SVR), and least squares support vector machine (LSSVM) [10][11][12][13][14] have been used in prediction problems. However, the neural network has the disadvantages of long training time, poor generalization ability and complex structure.…”

Section: Introductionmentioning

confidence: 99%

Prediction Model of Pigsty Temperature Based on ISSA-LSSVM

Zhang,

et al. 2023

Agriculture

View full text Add to dashboard Cite

The internal temperature of the pigsty has a great impact on the pigs. Keeping the temperature in the pigsty within a certain range is a pressing problem in environmental control. The current pigsty temperature regulation method is based mainly on manual and simple automatic control. There is rarely intelligent control, and such direct methods have problems such as low control accuracy, high energy consumption and untimeliness, which can easily lead to the occurrence of heat stress conditions. Therefore, this paper proposed an improved sparrow search algorithm (ISSA) based on a multi-strategy improvement to optimize the least squares support vector machine (LSSVM) to form a pigsty temperature prediction model. In the optimization process of the sparrow search algorithm (SSA), the initial position of the sparrow population was first generated by using the reverse good point set; secondly, the population number update formula was proposed to automatically adjust the number of discoverers and followers based on the number of iterations to improve the search ability of the algorithm; finally, the adaptive t-distribution was applied to the discoverer position variation to refine the discoverer population and further improve the search ability of the algorithm. Tests were conducted using 23 benchmark functions, and the results showed that ISSA outperformed SSA. By comparing it with the LSSVM models optimized by four standard algorithms, the prediction effect of the ISSA-LSSVM model was tested. In the end, the ISSA-LSSVM temperature prediction model had MSE of 0.0766, MAE of 0.2105, and R2 of 0.9818. The results showed that the proposed prediction model had the best prediction performance and prediction accuracy, and can provide accurate data support for the prediction and control of the internal temperature of the pigsty.

show abstract

Sliding mode control strategy of 3-UPS/S shipborne stable platform with LSTM neural network prediction

Cited by 8 publications

References 26 publications

A 3UPS/S Spherical Parallel Manipulator Designed for Robot-Assisted Hand Rehabilitation after Stroke

A 3UPS/S Spherical Parallel Manipulator Designed for Robot-Assisted Hand Rehabilitation after Stroke

An Offshore Self-Stabilized System Based on Motion Prediction and Compensation Control

Prediction Model of Pigsty Temperature Based on ISSA-LSSVM

Contact Info

Product

Resources

About