Wireless millirobots engineered to infiltrate intricate vascular networks within living organisms,particularly within constricted and confined spaces,hold immense promise for the future of medical treatments.However,w...Wireless millirobots engineered to infiltrate intricate vascular networks within living organisms,particularly within constricted and confined spaces,hold immense promise for the future of medical treatments.However,with their multifaceted and intricate designs,some robots often grapple with motion and functionality issues when confronted with tight spaces characterized by small cross-sectional dimensions.In this study,drawing inspiration from the high aspect ratio and undulating swimming patterns of snakes,a millimeter-scale,snake-like robot was designed and fabricated via a combination of extrusion-based four-dimensional(4D)printing and magnetic-responsive intelligent functional inks.A sophisticated motion control strategy was also developed,which enables the robots to perform various dynamic movements,such as undulating swimming,precise turns,graceful circular motions,and coordinated cluster movements,under diverse magnetic field variations.As a potential application,the snake robot can navigate and release drugs in a model coronary intervention vessel with tortuous channels and fluid filling.The novel design and promising applications of this snake robot are invaluable tools in future medical surgeries and interventions.展开更多
This paper studies motor joint control of a 4-degree-of-freedom(DoF)robotic manipulator using learning-based Adaptive Dynamic Programming(ADP)approach.The manipulator’s dynamics are modelled as an open-loop 4-link se...This paper studies motor joint control of a 4-degree-of-freedom(DoF)robotic manipulator using learning-based Adaptive Dynamic Programming(ADP)approach.The manipulator’s dynamics are modelled as an open-loop 4-link serial kinematic chain with 4 Degrees of Freedom(DoF).Decentralised optimal controllers are designed for each link using ADP approach based on a set of cost matrices and data collected from exploration trajectories.The proposed control strategy employs an off-line,off-policy iterative approach to derive four optimal control policies,one for each joint,under exploration strategies.The objective of the controller is to control the position of each joint.Simulation and experimental results show that four independent optimal controllers are found,each under similar exploration strategies,and the proposed ADP approach successfully yields optimal linear control policies despite the presence of these complexities.The experimental results conducted on the Quanser Qarm robotic platform demonstrate the effectiveness of the proposed ADP controllers in handling significant dynamic nonlinearities,such as actuation limitations,output saturation,and filter delays.展开更多
Objective:Robotic gastrectomy(RG)is increasingly used in the treatment of gastric cancer.However,studies on patients with clinical serosa-invasive(cT4a)gastric cancer remain scarce.This study aimed to compare the shor...Objective:Robotic gastrectomy(RG)is increasingly used in the treatment of gastric cancer.However,studies on patients with clinical serosa-invasive(cT4a)gastric cancer remain scarce.This study aimed to compare the shortand long-term outcomes of RG and laparoscopic gastrectomy(LG)in the treatment of stage cT4a gastric cancer.Methods:A retrospective analysis was conducted on the clinical data of patients with stage cT4a gastric cancer diagnosed and treated at eight high-volume tertiary teaching hospitals in China from 2016 to 2019.Propensity score matching(PSM)analysis and inverse probability of treatment weighting(IPTW)analysis was used to adjust for the imbalance in baseline characteristics.The primary research endpoint was the 3-year overall survival(OS)and disease-free survival(DFS).The secondary research endpoint was intraoperative outcomes and postoperative complications.Results:After IPTW and PSM adjustments,baseline characteristics between the RG and LG groups were comparable[standardized mean difference(SMD)<0.10].Post-PSM analysis revealed that the RG group exhibited longer operative time(P<0.001),lower postoperative complication rates(P<0.001),shorter postoperative hospital stays(P=0.037),and earlier initiation of adjuvant chemotherapy(P=0.041)compared with the LG group.Survival analysis demonstrated comparable 3-year OS(P=0.110)and DFS(P=0.088)in the PSM cohort,whereas the IPTW cohort showed superior OS(P=0.030)and DFS(P=0.046)for RG.No significant differences were observed in overall recurrence rates or recurrence sites between groups.Conclusions:For patients with stage cT4a gastric cancer,compared with the LG group,the RG group had shorter postoperative hospital stay,lower incidence of postoperative complications,earlier postoperative adjuvant chemotherapy,and no worse long-term efficacy.展开更多
Working principle for a four-axis oblique intersection line welding robot is analyzed. A mathematical model for welding torch orientation angle is established, and an interpolation algorithm based on time division is ...Working principle for a four-axis oblique intersection line welding robot is analyzed. A mathematical model for welding torch orientation angle is established, and an interpolation algorithm based on time division is proposed. The algorithm makes all interpolation points fall on a required curve in theory with no accumulated errors and a direct interpolation control on the saddle-shaped curve trajectory and space orientation angle can be achieved. It is shown by MATLAB simulation that the algorithm is real-time and fully meets the precision requirement. The algorithm has been applied to real robots.展开更多
Visual information acquisition is an important component of the AGV robot. The system adopts STM32F4 embedded application of the ARM Cortex-M4 kernel as the main control module,using shift algorithm to finish on a spe...Visual information acquisition is an important component of the AGV robot. The system adopts STM32F4 embedded application of the ARM Cortex-M4 kernel as the main control module,using shift algorithm to finish on a specific color piece of target tracking. For multi-sensor fusion of three methods,quaternion method is used to correct the attitude,the stability of AGV robot visual information acquisition and image clarity are improved.展开更多
In this paper, we study a STM32F4 as the core of the bionic design and implementation of embedded mobile robot. Bionic robot based on color sensor TCS3200 contacts surface color data sending instructions, by the PWM w...In this paper, we study a STM32F4 as the core of the bionic design and implementation of embedded mobile robot. Bionic robot based on color sensor TCS3200 contacts surface color data sending instructions, by the PWM wave to control the robot body tricolor LED color to achieve the surrounding color. Proven by a lot of experimental data, the bionic robot designed in this paper possesses the advantages of high stability and high accuracy, and bionic robot has completely independent behavior展开更多
基金the National Natural Science Foundation of China(Nos.52105421 and 52373050)the Guangdong Provincial Natural Science Foundation,China(No.2022A1515011621)+1 种基金the Science and Technology Projects in Guangzhou,China(Nos.202102080330 and 2024A04J6446)the Fundamental Research Funds for the Central Universities,Sun Yat-sen University(No.22qntd0101).
文摘Wireless millirobots engineered to infiltrate intricate vascular networks within living organisms,particularly within constricted and confined spaces,hold immense promise for the future of medical treatments.However,with their multifaceted and intricate designs,some robots often grapple with motion and functionality issues when confronted with tight spaces characterized by small cross-sectional dimensions.In this study,drawing inspiration from the high aspect ratio and undulating swimming patterns of snakes,a millimeter-scale,snake-like robot was designed and fabricated via a combination of extrusion-based four-dimensional(4D)printing and magnetic-responsive intelligent functional inks.A sophisticated motion control strategy was also developed,which enables the robots to perform various dynamic movements,such as undulating swimming,precise turns,graceful circular motions,and coordinated cluster movements,under diverse magnetic field variations.As a potential application,the snake robot can navigate and release drugs in a model coronary intervention vessel with tortuous channels and fluid filling.The novel design and promising applications of this snake robot are invaluable tools in future medical surgeries and interventions.
基金supported by the DEEPCOBOT project under Grant 306640/O70 funded by the Research Council of Norway.
文摘This paper studies motor joint control of a 4-degree-of-freedom(DoF)robotic manipulator using learning-based Adaptive Dynamic Programming(ADP)approach.The manipulator’s dynamics are modelled as an open-loop 4-link serial kinematic chain with 4 Degrees of Freedom(DoF).Decentralised optimal controllers are designed for each link using ADP approach based on a set of cost matrices and data collected from exploration trajectories.The proposed control strategy employs an off-line,off-policy iterative approach to derive four optimal control policies,one for each joint,under exploration strategies.The objective of the controller is to control the position of each joint.Simulation and experimental results show that four independent optimal controllers are found,each under similar exploration strategies,and the proposed ADP approach successfully yields optimal linear control policies despite the presence of these complexities.The experimental results conducted on the Quanser Qarm robotic platform demonstrate the effectiveness of the proposed ADP controllers in handling significant dynamic nonlinearities,such as actuation limitations,output saturation,and filter delays.
基金supported by Fujian Provincial Medical“Building High-level Hospitals,High-level Clinical Medical Centers and Key Clinical Specialty Projects”([2021]No.76)Fujian Research and Training Grants for Young and Middle-aged Leaders in Healthcare(No.[2022]954)。
文摘Objective:Robotic gastrectomy(RG)is increasingly used in the treatment of gastric cancer.However,studies on patients with clinical serosa-invasive(cT4a)gastric cancer remain scarce.This study aimed to compare the shortand long-term outcomes of RG and laparoscopic gastrectomy(LG)in the treatment of stage cT4a gastric cancer.Methods:A retrospective analysis was conducted on the clinical data of patients with stage cT4a gastric cancer diagnosed and treated at eight high-volume tertiary teaching hospitals in China from 2016 to 2019.Propensity score matching(PSM)analysis and inverse probability of treatment weighting(IPTW)analysis was used to adjust for the imbalance in baseline characteristics.The primary research endpoint was the 3-year overall survival(OS)and disease-free survival(DFS).The secondary research endpoint was intraoperative outcomes and postoperative complications.Results:After IPTW and PSM adjustments,baseline characteristics between the RG and LG groups were comparable[standardized mean difference(SMD)<0.10].Post-PSM analysis revealed that the RG group exhibited longer operative time(P<0.001),lower postoperative complication rates(P<0.001),shorter postoperative hospital stays(P=0.037),and earlier initiation of adjuvant chemotherapy(P=0.041)compared with the LG group.Survival analysis demonstrated comparable 3-year OS(P=0.110)and DFS(P=0.088)in the PSM cohort,whereas the IPTW cohort showed superior OS(P=0.030)and DFS(P=0.046)for RG.No significant differences were observed in overall recurrence rates or recurrence sites between groups.Conclusions:For patients with stage cT4a gastric cancer,compared with the LG group,the RG group had shorter postoperative hospital stay,lower incidence of postoperative complications,earlier postoperative adjuvant chemotherapy,and no worse long-term efficacy.
文摘Working principle for a four-axis oblique intersection line welding robot is analyzed. A mathematical model for welding torch orientation angle is established, and an interpolation algorithm based on time division is proposed. The algorithm makes all interpolation points fall on a required curve in theory with no accumulated errors and a direct interpolation control on the saddle-shaped curve trajectory and space orientation angle can be achieved. It is shown by MATLAB simulation that the algorithm is real-time and fully meets the precision requirement. The algorithm has been applied to real robots.
基金supported by the National Key Technology R&D Program(2015BAK06B04)the key technology R&D Program of Tianjin(14ZCZDSF00022,15ZXZNGX00260)
文摘Visual information acquisition is an important component of the AGV robot. The system adopts STM32F4 embedded application of the ARM Cortex-M4 kernel as the main control module,using shift algorithm to finish on a specific color piece of target tracking. For multi-sensor fusion of three methods,quaternion method is used to correct the attitude,the stability of AGV robot visual information acquisition and image clarity are improved.
文摘In this paper, we study a STM32F4 as the core of the bionic design and implementation of embedded mobile robot. Bionic robot based on color sensor TCS3200 contacts surface color data sending instructions, by the PWM wave to control the robot body tricolor LED color to achieve the surrounding color. Proven by a lot of experimental data, the bionic robot designed in this paper possesses the advantages of high stability and high accuracy, and bionic robot has completely independent behavior
