Multi-degree-of-freedom Internal Model Control for Optoelectronic Stabilized Platform Based on Sliding Mode Friction Compensation

Shuaishuai Sui,Yiping Yao,Tong Zhao 제어·로봇·시스템학회 2023 International Journal of Control, Automation, and Vol.21 No.12

A multi-degree-of-freedom (multi-DOF) control method is proposed in this paper for the optoelectronic platform affected by internal and external disturbances. First, internal model control (IMC) is used to track the desired signal, and combined with radial basis function neural network (RBFNN)-based sliding mode control (SMC) to compensate for friction torque and weaken model uncertainty. Then, linear active disturbance rejection control (LADRC) is introduced to observe and compensate for sensor noise as well as external unknown disturbances, so that the optoelectronic platform can operate under complex working conditions. The input and disturbance sensitivity functions in a pure feedback control system cannot reach their minimum values in the same frequency band, so there is an inherent contradiction between their tracking and disturbance rejection performance. Combining IMC-SMC-RBFNN with LADRC as a multi-DOF controller can guarantee both tracking and disturbance rejection performance. Lyapunov theory and Barbalat lemma prove the asymptotic stability of the control system. Simulations show that the multi-DOF controller has a good control effect under the mixed disturbances such as parameter perturbation, friction torque and sensor noise, which has reference value for the development of practical optoelectronic platform systems.

Pd nanoparticles supported on N-doped porous carbons derived from ZIF-67: Enhanced catalytic performance in phenol hydrogenation

Shuaishuai Ding,Chunhua Zhang,Yefei Liu,Hong Jiang,Weihong Xing,Rizhi Chen 한국공업화학회 2017 Journal of Industrial and Engineering Chemistry Vol.46 No.-

We reported a Pd@CN catalyst made of Pd nanoparticles supported on a N-doped carbon derived fromZIF-67. The CN materials with micro/mesoporous structures were well developed for the loading of Pdnanoparticles and improving the catalytic performances. With the increase of calcination temperature ofZIF-67, the BET surface of CN materials initially increased and then reduced. Moreover, the highercalcination temperature would lead to lower nitrogen content in CN materials, causing lower selectivityof phenol hydrogenation to cyclohexanone. Our Pd@CN600 catalyst achieved a conversion of ca. 95% and aselectivity of ca. 95%, and exhibited excellent stability during recycling experiments

Effects of gear modifications on the dynamic characteristics of wind turbine gearbox considering elastic support of the gearbox

Shuaishuai Wang,Caichao Zhu,Chaosheng Song,Huachao Liu,Jianjun Tan,Houyi Bai 대한기계학회 2017 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.31 No.3

The reliability and service life of wind turbines are directly influenced by the dynamic performance of the gearbox under the timevarying wind loads. The control of vibration behavior is essential for the achievement of a 20-year service life. We developed a rigidflexible coupled dynamic model for a wind turbine gearbox. The planet carrier, the housing, and the bedplate are modelled as flexibilities while other components are assumed as rigid bodies. The actual three points elastic supporting are considered and a strip based mesh model is used to represent the engagement of the gear pairs. The effects of gear tooth modifications on the dynamics were investigated. Finally, we conducted a dynamic test for the wind turbine gearbox in the wind field. Results showed that the contact characteristics of gear pairs were improved significantly; the peak-to-peak value of transmission error of each gear pair was reduced; the amplitudes of the vibration acceleration and the structural noise of the wind turbine gearbox were lowered after suitable tooth modification.

A free gait generation method for quadruped robots over rough terrains containing forbidden areas

Shuaishuai Zhang,Xuewen Rong,Yi-bin Li,Bin Li 대한기계학회 2015 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.29 No.9

Planning a robust gait is one of the most basic aspects to enable a quadruped robot to walk stably on rough terrains. In this paper, wefocus on the scenario where a quadruped robot travelling on the rough terrains containing forbidden areas, and a free gait generationmethod for quadruped robot is proposed. Under the assumption that a set of the positions which can be selected as the foothold is given,the quadruped robot can select the swing foot sequence and choose the best foothold for the swing foot automatically. A body sway motionis included into the motion planning of the free gait to enlarge the stability margin of the robot. With the aid of the sway motion, thestability margin of the robot is no less than the minimum stability margin during the whole walking process. In order to guarantee thelocomotion continuity of the quadruped robot, a COG trajectory which has continuous velocity and acceleration profiles is automaticallygenerated. Moreover, the locomotion speed of the robot is improved by ensuring the kinematic margin of the selected swing foot to bezero just before this foot lift-off the ground. With the free gait generation method proposed in this paper, the robot can autonomouslynavigate through rough terrains as soon as possible on the condition that the robot has enough stability margin. The simulation resultsshow the correctness and effectiveness of the proposed method.

Piezo channels in the urinary system: Correspondence

Hu Shuaishuai,Yao Xudong 생화학분자생물학회 2023 Experimental and molecular medicine Vol.55 No.-

We read an informative review article by Li et al.1, titled “Piezo channels in the urinary system”. They report that mRNA expression of Piezo2 increased significantly in both human bladder cancer tissues and mouse bladder cancer tissues. They further found that Piezo2 only correlates with tumor stage. However, this conclusion was based on the results of only one experiment. I read the original study that the author cited in the review. The study found that Piezo2 mRNA was significantly increased in the pT2 tumor stage compared to the pT0 tumor stage, but with no significant difference between the pT2 tumor stage and pT1 tumor stage. Therefore, it is not accurate to state that Piezo2 correlates with tumor stage based on this single experiment. This review provides very little information about the role of Piezo2 in bladder cancer. Here, we would like to provide more comprehensive information regarding the role of Piezo2 in bladder cancer based on current studies and tumor datasets.

Study on the Mechanism of Grouting in the Construction of Metro Cross Passage

CUI SHUAISHUAI,Wu Ke,유충식,Zhang Qianjn,Zhang Zheng,Zhao Jiahui 한국지반신소재학회 2019 한국토목섬유학회 학술발표회 Vol.2019 No.3

Interfacial Polyelectrolyte Complexation Spinning of Cellulose Nanofibers/CdTe Quantum Dots for Anti-counterfeiting Fluorescent Textiles

Shulin Cai,Shuaishuai Hu,Jianming Wu,An Huang,Lihong Geng,Xiangfang Peng 한국섬유공학회 2022 Fibers and polymers Vol.23 No.5

Cellulose-based fluorescent fibers were successfully fabricated by interfacial polyelectrolyte complexation (IPC)spinning, in which thioglycolic acid-modified CdTe quantum dots (QDs) were incorporated. The fibers exhibited differentfluorescent colors depending on different sizes of CdTe QDs. The IPC spinning process based on the progressive selfassemblyof negatively charged cellulose nanofibers (CNFs) and positively charged chitosan endowed the fibers highorientation degree. Together with the superior mechanical property of CNFs and the strong interfacial ionic bond andhydrogen bond interaction between CNFs and chitosan, the fluorescent fibers showed a high tensile strength above 689 MPaand toughness above 25 MJ/m3, which provided a guarantee for weaving the fluorescent fibers into textiles. With excellentoptical and mechanical performance, the resulting fluorescent fibers showed a promising potential as flexible wearable anticounterfeitingdevices, which the hard-to-see tag woven using the fluorescent fibers appeared clearly under 365 nmultraviolet light illumination. This paper would provide a new avenue for the preparation of high-performance environmentfriendlyfluorescent anti-counterfeiting textiles.

Mechanical Mechanism of Main Tunnels and Cross Passage Construction - A 3D Numerical Investigation

유충식,Cui Shuaishuai,Wu Ke,Zhang Qianjn,Zhang Zheng,Zhao Jiahui 한국지반신소재학회 2019 한국지반신소재학회 논문집 Vol.18 No.1

This paper presents the results of a three-dimensional numerical investigation into the mechanical mechanism of main tunnels and cross passage construction. Aimed at the complex space structure composed of two main tunnels and cross passage, 3D numerical model of the structure and surrounding rock was built to analyze the influence. Comparative analysis of different buried depths were carried out. The results of the study indicate that the stress concentration was occurred in the intersecting linings, especially in the opening side lining, which leads to an unfavorable form of force that is pulled up by the upper and lower sections in the intersecting linings due to the construction of the cross passage. The excavation of the cross passage also destroys the stability of the original soil layer and causes settlement of the surface and main tunnels. Practical implications of the findings are discussed.

Mechanical Mechanism of Main Tunnels and Cross Passage Construction - A 3D Numerical Investigation

Yoo, Chungsik,Shuaishuai, Cui,Ke, Wu,Qianjn, Zhang,Zheng, Zhang,Jiahui, Zhao Korean Geosynthetics Society 2019 한국지반신소재학회 논문집 Vol.18 No.1

This paper presents the results of a three-dimensional numerical investigation into the mechanical mechanism of main tunnels and cross passage construction. Aimed at the complex space structure composed of two main tunnels and cross passage, 3D numerical model of the structure and surrounding rock was built to analyze the influence. Comparative analysis of different buried depths were carried out. The results of the study indicate that the stress concentration was occurred in the intersecting linings, especially in the opening side lining, which leads to an unfavorable form of force that is pulled up by the upper and lower sections in the intersecting linings due to the construction of the cross passage. The excavation of the cross passage also destroys the stability of the original soil layer and causes settlement of the surface and main tunnels. Practical implications of the findings are discussed.

CDK1 promotes the proliferation of melanocytes in Rex rabbits

Dai Yingying,Hu Shuaishuai,Bai Shaocheng,Li Jiali,Yang Naisu,Zhai Pin,Zhao Bohao,Chen Yang,Wu Xinsheng 한국유전학회 2022 Genes & Genomics Vol.44 No.10

Background: The fur color constitutes one of the most important economic characteristics of fur animals and is determined by the content of melanin. A previous study has shown that the cyclin-dependent kinase 1 (CDK1) is a member of the protein kinase family, involved in forming the color of the fur in Rex rabbits. However, its effect on the melanocytes remains unclear. Objective: This study aimed to provide evidence for the role of CDK1 in melanogenesis. Methods: This study measured the expression of CDK1 in Rex rabbit skins of six coat colors using qRT-PCR. The CDK1-mediated regulation of the pigmentation-related genes and cyclin-dependent kinases were analyzed. The melanin content, proliferation, and apoptosis of the melanocytes were analyzed using the NaOH, CCK8, and Annexin V-FITC methods. Results: The CDK1 expression in the skin of the rex rabbits with different coat colors was found to be regular, and the expression level was found to be the highest in the skin of the black rex rabbits (P < 0.05). The overexpression/knockdown of CDK1 was found to significantly increase/decrease the melanin content in the melanocytes (P < 0.01). Besides, CDK1 was found to significantly promote the proliferation of the melanocyte and inhibit apoptosis (P < 0.01). Furthermore, the overexpression of CDK1 was found to significantly affect the expression of the other melanin-related genes like TYR, PMEL, DCT, as well as the mRNA expression of the cyclin-dependent kinases CDK4, CDK6, CDK8, CCNB1. Conclusions: The results indicated that CDK1 can serve as a key gene regulating melanogenesis, melanocyte proliferation, and apoptosis, providing a new theoretical basis for studying the mechanism by which the different colors of the fur evolve in mammals.