Robot hands have been developing during the last few decades. There are many mechanical structures and analyti?cal methods for di erent hands. But many tough problems still limit robot hands to apply in homelike envir...Robot hands have been developing during the last few decades. There are many mechanical structures and analyti?cal methods for di erent hands. But many tough problems still limit robot hands to apply in homelike environment. The ability of grasping objects covering a large range of sizes and various shapes is fundamental for a home service robot to serve people better. In this paper, a new grasping mode based on a novel sucked?type underactuated(STU) hand is proposed. By combining the flexibility of soft material and the e ect of suction cups, the STU hand can grasp objects with a wide range of sizes, shapes and materials. Moreover, the new grasping mode is suitable for some situations where the force closure is failure. In this paper, we deduce the e ective range of sizes of objects which our hand using the new grasping mode can grasp. Thanks to the new grasping mode, the ratio of grasping size between the biggest object and the smallest is beyond 40, which makes it possible for our robot hand to grasp diverse objects in our daily life. For example, the STU hand can grasp a soccer(220 mm diameter, 420 g) and a fountain pen(9 mm diameter, 9 g). What's more, we use the rigid body equilibrium conditions to analysis the force condition. Experiment evaluates the high load capacity, stability of the new grasping mode and displays the versatility of the STU hand. The STU hand has a wide range of applications especially in unstructured environment.展开更多
Endoscopic submucosal dissection(ESD) has allowed the achievement of histologically curative en bloc resection of gastrointestinal neoplasms regardless of size,permitting the resection of previously non-resectable tum...Endoscopic submucosal dissection(ESD) has allowed the achievement of histologically curative en bloc resection of gastrointestinal neoplasms regardless of size,permitting the resection of previously non-resectable tumors.The ESD technique for treatment of early gastric cancer has spread rapidly in Japan and a few other Asian countries due to its excellent eradication rate compared to endoscopic mucosal resection.Although numerous electrosurgical knives have been developed for ESD,technical difficulties and high complication rates(bleeding and perforation) have limited their use worldwide.We developed the grasping type scissor forceps(GSF) to resolve such ESD-related problems.Our animal and preliminary clinical studies showed that ESD using GSF is a safe(no intraoperative complication) and technically efficient(curative en bloc resection rate 92%) method for dissection of early gastrointestinal tumors.The use of GSF is a promising option for performing ESD on early stage GI tract tumors both safely and effectively.展开更多
The performance of deep learning(DL)networks has been increased by elaborating the network structures. However, the DL netowrks have many parameters, which have a lot of influence on the performance of the network. We...The performance of deep learning(DL)networks has been increased by elaborating the network structures. However, the DL netowrks have many parameters, which have a lot of influence on the performance of the network. We propose a genetic algorithm(GA) based deep belief neural network(DBNN) method for robot object recognition and grasping purpose. This method optimizes the parameters of the DBNN method, such as the number of hidden units, the number of epochs, and the learning rates, which would reduce the error rate and the network training time of object recognition. After recognizing objects, the robot performs the pick-andplace operations. We build a database of six objects for experimental purpose. Experimental results demonstrate that our method outperforms on the optimized robot object recognition and grasping tasks.展开更多
Capture is a key component for on?orbit service and space debris clean. The current research of capture on?orbit focuses on using special capture devices or full?actuated space arms to capture cooperative targets. How...Capture is a key component for on?orbit service and space debris clean. The current research of capture on?orbit focuses on using special capture devices or full?actuated space arms to capture cooperative targets. However, the structures of current capture devices are complex, and both space debris and abandoned spacecraft are non?cooperative targets. To capture non?cooperative targets in space, a lightweight, less driven under?actuated robotic hand is proposed in this paper, which composed by tendon?pulley transmission and double?stage mechanisms, and always driven by only one motor in process of closing finger. Because of the expandability, general grasping model is constructed. The equivalent joint driving forces and general grasping force are analyzed based on the model and the principle of virtual work. Which reveal the relationship among tendon driving force, joint driving forces and grasping force. In order to configure the number of knuckles of finger, a new analysis method which takes the maximum grasping space into account, is proposed. Supposing the maximum grasped object is an envelope circle with diameter of 2.5m. In the condition, a finger grasping maximum envelope circle with different knuckles is modeled. And the finger lengths with corresponding knuckles are calculated out. The finger length which consists of three knuckles is the shortest among under?actuated fingers consists of not more than five knuckles. Finally, the principle prototype and prototype robotic hand which consists of two dingers are designed and assembled. Experiments indicate that the under?actuated robotic hand can satisfy the grasp requirements.展开更多
Directly grasping the tightly stacked objects may cause collisions and result in failures,degenerating the functionality of robotic arms.Inspired by the observation that first pushing objects to a state of mutual sepa...Directly grasping the tightly stacked objects may cause collisions and result in failures,degenerating the functionality of robotic arms.Inspired by the observation that first pushing objects to a state of mutual separation and then grasping them individually can effectively increase the success rate,we devise a novel deep Q-learning framework to achieve collaborative pushing and grasping.Specifically,an efficient non-maximum suppression policy(PolicyNMS)is proposed to dynamically evaluate pushing and grasping actions by enforcing a suppression constraint on unreasonable actions.Moreover,a novel data-driven pushing reward network called PR-Net is designed to effectively assess the degree of separation or aggregation between objects.To benchmark the proposed method,we establish a dataset containing common household items dataset(CHID)in both simulation and real scenarios.Although trained using simulation data only,experiment results validate that our method generalizes well to real scenarios and achieves a 97%grasp success rate at a fast speed for object separation in the real-world environment.展开更多
BACKGROUND Endoscopic submucosal dissection(ESD)is widely accepted for early gastric cancer(EGC)without lymph node metastasis,although ESD is challenging,even for small lesions,in the greater curvature(GC)of the upper...BACKGROUND Endoscopic submucosal dissection(ESD)is widely accepted for early gastric cancer(EGC)without lymph node metastasis,although ESD is challenging,even for small lesions,in the greater curvature(GC)of the upper(U)and middle(M)thirds of the stomach.Grasping forceps-assisted endoscopic resection(GF-ER)is a type of endoscopic mucosal resection that is performed via a double-channel endoscope.AIM To investigate the safety and efficacy of GF-ER vs ESD in the GC of the stomach’s U and M regions.METHODS We retrospectively reviewed the medical records of 506 patients who underwent ER of 522 EGC lesions in the stomach’s U and M regions in three institutions between January 2016 and May 2020.Nine lesions from eight patients who underwent GF-ER for EGC(the GF-ER group)were compared to 63 lesions from 63 patients who underwent ESD(the ESD group).We also performed a subgroup analysis of small lesions(≤10 mm)in 6 patients(7 lesions)from the GF-ER group and 20 patients(20 lesions)from the ESD group.RESULTS There were no statistically significant differences between the GF-ER and ESD groups in the en bloc resection rates(100%vs 100%)and the R0 resection rates(100%vs 98.4%).The median procedure time in the GF-ER group was shorter than that in the ESD group(4.0 min vs 55.0 min,P<0.01).There were no adverse events in the GF-ER group,although five perforations(8.0%)and 1 case of postoperative bleeding(1.6%)were observed in the ESD group.When we only considered lesions that were≤10 mm,the median procedure time in the GF-ER group was still shorter than that in the ESD group(4.0 min vs 35.0 min,P<0.01).There were no adverse events in the GF-ER group,although 1 case of perforation(1.6%)were observed in the ESD group.CONCLUSION These findings suggest that GF-ER may be an effective therapeutic option for small lesions in the GC of the stomach’s U and M regions.展开更多
Robotic grasps play an important role in the service and industrial fields,and the robotic arm can grasp the object properly depends on the accuracy of the grasping detection result.In order to predict grasping detect...Robotic grasps play an important role in the service and industrial fields,and the robotic arm can grasp the object properly depends on the accuracy of the grasping detection result.In order to predict grasping detection positions for known or unknown objects by a modular robotic system,a convolutional neural network(CNN)with the residual block is proposed,which can be used to generate accurate grasping detection for input images of the scene.The proposed model architecture was trained on the standard Cornell grasp dataset and evaluated on the test dataset.Moreover,it was evaluated on different types of household objects and cluttered multi-objects.On the Cornell grasp dataset,the accuracy of the model on image-wise splitting detection and object-wise splitting detection achieved 95.5%and 93.6%,respectively.Further,the real detection time per image was 109 ms.The experimental results show that the model can quickly detect the grasping positions of a single object or multiple objects in image pixels in real time,and it keeps good stability and robustness.展开更多
It is of great significance to have a clear understanding of the international environment that China faces. But this is an uneasy job. Since September 11, the world situation has become so complicated that it is hard...It is of great significance to have a clear understanding of the international environment that China faces. But this is an uneasy job. Since September 11, the world situation has become so complicated that it is hard to grasp its essence even with painstaking efforts. To judge such an already complicated international environment from China’s perspective adds more difficulties, for different people usually have different views due to the different angles from which they see the situation and different methods they adopt. This, understandably, leads to hot debates within the Chinese academic circles. To provide a stage for exchange of views, at the invitation of the CIR Expert Forum, some well-known scholars and experts on international relations from Beijing gathered to hold a symposium on November 5, 2002, with the theme of "How to assess the international environment that China faces". The speeches at the symposium are published in two installments. Following are the second half.展开更多
Laparoscopic surgery is a new abdominal surgical procedure which helps the patients in many ways like less hospital stay, faster recovery and reduced pain. The main disadvantage in this surgical procedure is the reduc...Laparoscopic surgery is a new abdominal surgical procedure which helps the patients in many ways like less hospital stay, faster recovery and reduced pain. The main disadvantage in this surgical procedure is the reduced haptic perception by the surgeons due to the usage of laparoscopic instrument to handle tissues which in turn cause damage of it as compared to an open surgery. The primary aim of this investigation was to compare the pinch force applied during two different methods of laparoscopic grasping: Finger and Palm grasp. A low cost force sensing resistor tailor made for the grasper tip was designed and fabricated for quantifying the grasper tip force in the study. The results indicate more pinch force was applied during palm grasp as compared to finger grasp so as to prevent the slippage of the tissues from the jaws of the laparoscopic graspers.展开更多
The current study examined the effects of band therapy using music on grasping power, depression, and personal relationships among residents of a nursing home. Thirty subjects participated in the study. The band thera...The current study examined the effects of band therapy using music on grasping power, depression, and personal relationships among residents of a nursing home. Thirty subjects participated in the study. The band therapy included greetings, warm-up exercises with music, singing with dance, playing instruments, closing speech, and stretching with background music. Band therapy was held for 40 minutes once per week, for a total of four sessions, in the activity room of the nursing home. Findings showed that grasping power, depression, and personal relationships were improved at posttest, but the differences were not statistically significant. A better study design to compare the effects of band therapy with the other group, and a more simple and repeated intervention for the elderly to follow without stress might be necessary.展开更多
The Chinese government officially resumed its exercise of sovereignty over Hong Kong on July 1, 1997. On this historic occasion, the China National Machinery Import and Export Corporation officially renamed itself as ...The Chinese government officially resumed its exercise of sovereignty over Hong Kong on July 1, 1997. On this historic occasion, the China National Machinery Import and Export Corporation officially renamed itself as the China Machinery Import and Export Group Corporation, with the approval of the relevant department of the state, and moved into its new office building. The change of name marks the progress it has achieved in a the course of exploring the establishment of a modern enterprise system. It was designated by the State Council in 1994 as one of the first group of 100 enterprises in China to introduce the modern enterprise system on a trial basis.In particular since 1995, when its展开更多
The intrinsic compliance of soft materials endows soft robots with great advantages to achieve large deformation and adaptive interactions in grasping tasks.However,current soft grippers usually focus on the in-plane ...The intrinsic compliance of soft materials endows soft robots with great advantages to achieve large deformation and adaptive interactions in grasping tasks.However,current soft grippers usually focus on the in-plane large deformation and load capacity but ignore the effect of out-of-plane external loads,which may lead to instability in practical scenarios.This problem calls for stiffness design along multiple directions to withstand not only in-plane interacting forces with objects,but also unexpected outof-plane loads.In this paper,we design a new type of soft finger by embedding an endoskeleton inside the widely-used PneuNets actuator,and the endoskeleton layout is optimized to achieve a remarkable bending deflection and limited lateral deflection under combined external in-plane and out-of-plane loads.Based on the multi-objective topology optimization approach,the key structural features of the optimized endoskeleton are extracted and parameterized.The multi-material soft fingers are fabricated by the silicone compound mold method.Static and dynamic experiment results validate that the soft gripper with endoskeleton embedded exhibits remarkably improved out-of-plane stiffness,without sacrificing the in-plane bending flexibility,and leads to more stable grasping.展开更多
Although notable progress has been made in the study of Steady-State Visual Evoked Potential(SSVEP)-based Brain-Computer Interface(BCI),several factors that limit the practical applications of BCIs still exist.One of ...Although notable progress has been made in the study of Steady-State Visual Evoked Potential(SSVEP)-based Brain-Computer Interface(BCI),several factors that limit the practical applications of BCIs still exist.One of these factors is the importability of the stimulator.In this study,Augmented Reality(AR)technology was introduced to present the visual stimuli of SSVEP-BCI,while the robot grasping experiment was designed to verify the applicability of the AR-BCI system.The offline experiment was designed to determine the best stimulus time,while the online experiment was used to complete the robot grasping task.The offline experiment revealed that better information transfer rate performance could be achieved when the stimulation time is 2 s.Results of the online experiment indicate that all 12 subjects could control the robot to complete the robot grasping task,which indicates the applicability of the AR-SSVEP-humanoid robot(NAO)system.This study verified the reliability of the AR-BCI system and indicated the applicability of the AR-SSVEP-NAO system in robot grasping tasks.展开更多
Inspired by the morphology of human fingers,this paper proposes an underactuated rigid-soft coupled robotic gripper whose finger is designed as the combination of a rigid skeleton and a soft tissue.Different from the ...Inspired by the morphology of human fingers,this paper proposes an underactuated rigid-soft coupled robotic gripper whose finger is designed as the combination of a rigid skeleton and a soft tissue.Different from the current grippers who have multi-point contact or line contact with the target objects,the proposed robotic gripper enables surface contact and leads to flexible grasping and robust holding.The actuated mechanism,which is the palm of proposed gripper,is optimized for excellent operability based on a mathematical model.Soft material selection and rigid skeleton structure of fingers are then analyzed through a series of dynamic simulations by RecurDyn and Adams.After above design process including topology analysis,actuated mechanism optimization,soft material selection and rigid skeleton analysis,the rigid-soft coupled robotic gripper is fabricated via 3D printing.Finally,the grasping and holding capabilities are validated by experiments testing the stiffness of a single finger and the impact resistance of the gripper.Experimental results show that the proposed rigid-soft coupled robotic gripper can adapt to objects with different properties(shape,size,weight and softness)and hold them steadily.It confirms the feasibility of the design procedure,as well as the compliant and dexterous grasping capabilities of proposed rigid-soft coupled gripper.展开更多
Developing large,soft grippers with high omnidirectional load(above 40 kg)has always been challenging.We address this challenge by developing a powerful soft gripper that can grasp the human body based on a soft-enclo...Developing large,soft grippers with high omnidirectional load(above 40 kg)has always been challenging.We address this challenge by developing a powerful soft gripper that can grasp the human body based on a soft-enclosed grasping structure and a soft-rigid coupling structure.The envelope size of the proposed soft gripper is 611.6 mm×559 mm×490.7 mm,the maximum grasping size is 417 mm,and the payload on the human body is more than 90 kg,which has exceeded most existing soft grippers.Furthermore,the grasping force prediction of the gripper is achieved through theoretical modeling.The primary contribution of this work is to overcome the size and payload limits of current soft grippers and implement a human-grasping experiment based on the soft-grasping method.展开更多
To improve the grasping power of soft robots,inspired by the scene of intertwined and interdependent vine branches safely clinging to habitats in a violent storm and the phenomenon of large grasping force after being ...To improve the grasping power of soft robots,inspired by the scene of intertwined and interdependent vine branches safely clinging to habitats in a violent storm and the phenomenon of large grasping force after being entangled by aquatic plants,this paper proposes a soft robotic gripper with multi-stem twining.The proposed robotic gripper can realize a larger contact area of surrounding or containing object and more layers of a twining object than the current twining gripping methods.It not only retains the adaptive advantages of twining grasping but also improves the grasping force.First,based on the mechanical characteristics of the multi-stem twining of the gripper,the twining grasping model is developed.Then,the force on the fiber is deduced by using the twining theory,and the axial force of the gripper is analyzed based on the equivalent model of the rubber ring.Finally,the torsion experiments of fibers and the grasping experiments of the gripper are designed and conducted.The torsion experiment of fibers verifies the influence of a different number of fiber ropes and fiber torque on the grasping force,and the grasping experiment reflects the large load of the gripper and the high adaptability and practicability under different tasks.展开更多
In this paper,we propose a fully Soft Bionic Grasping Device(SBGD),which has advantages in automatically adjusting the grasping range,variable stiffness,and controllable bending shape.This device consists of soft grip...In this paper,we propose a fully Soft Bionic Grasping Device(SBGD),which has advantages in automatically adjusting the grasping range,variable stiffness,and controllable bending shape.This device consists of soft gripper structures and a soft bionic bracket structure.We adopt the local thin-walled design in the soft gripper structures.This design improves the grippers’bending efficiency,and imitate human finger’s segmental bending function.In addition,this work also proposes a pneumatic soft bionic bracket structure,which not only can fix grippers,but also can automatically adjust the grasping space by imitating the human adjacent fingers’opening and closing movements.Due to the above advantages,the SBGD can grasp larger or smaller objects than the regular grasping devices.Particularly,to grasp small objects reliably,we further present a new Pinching Grasping(PG)method.The great performance of the fully SBGD is verified by experiments.This work will promote innovative development of the soft bionic grasping robots,and greatly meet the applications of dexterous grasping multi-size and multi-shape objects.展开更多
The application of robotic grasping for agricultural products pushes automation in agriculture-related industries.Cucumber,a common vegetable in greenhouses and supermarkets,often needs to be grasped from a cluttered ...The application of robotic grasping for agricultural products pushes automation in agriculture-related industries.Cucumber,a common vegetable in greenhouses and supermarkets,often needs to be grasped from a cluttered scene.In order to realize efficient grasping in cluttered scenes,a fully automatic cucumber recognition,grasping,and palletizing robot system was constructed in this paper.The system adopted Yolact++deep learning network to segment cucumber instances.An early fusion method of F-RGBD was proposed,which increases the algorithm's discriminative ability for these appearance-similar cucumbers at different depths,and at different occlusion degrees.The results of the comparative experiment of the F-RGBD dataset and the common RGB dataset on Yolact++prove the positive effect of the F-RGBD fusion method.Its segmentation masks have higher quality,are more continuous,and are less false positive for prioritizing-grasping prediction.Based on the segmentation result,a 4D grab line prediction method was proposed for cucumber grasping.And the cucumber detection experiment in cluttered scenarios is carried out in the real world.The success rate is 93.67%and the average sorting time is 9.87 s.The effectiveness of the cucumber segmentation and grasping pose acquisition method is verified by experiments.展开更多
基金National Natural Science Foundation of China(Grant Nos.U1613216,61573333)
文摘Robot hands have been developing during the last few decades. There are many mechanical structures and analyti?cal methods for di erent hands. But many tough problems still limit robot hands to apply in homelike environment. The ability of grasping objects covering a large range of sizes and various shapes is fundamental for a home service robot to serve people better. In this paper, a new grasping mode based on a novel sucked?type underactuated(STU) hand is proposed. By combining the flexibility of soft material and the e ect of suction cups, the STU hand can grasp objects with a wide range of sizes, shapes and materials. Moreover, the new grasping mode is suitable for some situations where the force closure is failure. In this paper, we deduce the e ective range of sizes of objects which our hand using the new grasping mode can grasp. Thanks to the new grasping mode, the ratio of grasping size between the biggest object and the smallest is beyond 40, which makes it possible for our robot hand to grasp diverse objects in our daily life. For example, the STU hand can grasp a soccer(220 mm diameter, 420 g) and a fountain pen(9 mm diameter, 9 g). What's more, we use the rigid body equilibrium conditions to analysis the force condition. Experiment evaluates the high load capacity, stability of the new grasping mode and displays the versatility of the STU hand. The STU hand has a wide range of applications especially in unstructured environment.
文摘Endoscopic submucosal dissection(ESD) has allowed the achievement of histologically curative en bloc resection of gastrointestinal neoplasms regardless of size,permitting the resection of previously non-resectable tumors.The ESD technique for treatment of early gastric cancer has spread rapidly in Japan and a few other Asian countries due to its excellent eradication rate compared to endoscopic mucosal resection.Although numerous electrosurgical knives have been developed for ESD,technical difficulties and high complication rates(bleeding and perforation) have limited their use worldwide.We developed the grasping type scissor forceps(GSF) to resolve such ESD-related problems.Our animal and preliminary clinical studies showed that ESD using GSF is a safe(no intraoperative complication) and technically efficient(curative en bloc resection rate 92%) method for dissection of early gastrointestinal tumors.The use of GSF is a promising option for performing ESD on early stage GI tract tumors both safely and effectively.
文摘The performance of deep learning(DL)networks has been increased by elaborating the network structures. However, the DL netowrks have many parameters, which have a lot of influence on the performance of the network. We propose a genetic algorithm(GA) based deep belief neural network(DBNN) method for robot object recognition and grasping purpose. This method optimizes the parameters of the DBNN method, such as the number of hidden units, the number of epochs, and the learning rates, which would reduce the error rate and the network training time of object recognition. After recognizing objects, the robot performs the pick-andplace operations. We build a database of six objects for experimental purpose. Experimental results demonstrate that our method outperforms on the optimized robot object recognition and grasping tasks.
基金Supported by Joint Funds of National Natural Science Foundation of China(Grant No.U1613201)Shenzhen Research Funds(JCYJ20170413104438332)
文摘Capture is a key component for on?orbit service and space debris clean. The current research of capture on?orbit focuses on using special capture devices or full?actuated space arms to capture cooperative targets. However, the structures of current capture devices are complex, and both space debris and abandoned spacecraft are non?cooperative targets. To capture non?cooperative targets in space, a lightweight, less driven under?actuated robotic hand is proposed in this paper, which composed by tendon?pulley transmission and double?stage mechanisms, and always driven by only one motor in process of closing finger. Because of the expandability, general grasping model is constructed. The equivalent joint driving forces and general grasping force are analyzed based on the model and the principle of virtual work. Which reveal the relationship among tendon driving force, joint driving forces and grasping force. In order to configure the number of knuckles of finger, a new analysis method which takes the maximum grasping space into account, is proposed. Supposing the maximum grasped object is an envelope circle with diameter of 2.5m. In the condition, a finger grasping maximum envelope circle with different knuckles is modeled. And the finger lengths with corresponding knuckles are calculated out. The finger length which consists of three knuckles is the shortest among under?actuated fingers consists of not more than five knuckles. Finally, the principle prototype and prototype robotic hand which consists of two dingers are designed and assembled. Experiments indicate that the under?actuated robotic hand can satisfy the grasp requirements.
基金This work was supported by the National Natural Science Foundation of China(61873077,61806062)Zhejiang Provincial Major Research and Development Project of China(2020C01110)Zhejiang Provincial Key Laboratory of Equipment Electronics.
文摘Directly grasping the tightly stacked objects may cause collisions and result in failures,degenerating the functionality of robotic arms.Inspired by the observation that first pushing objects to a state of mutual separation and then grasping them individually can effectively increase the success rate,we devise a novel deep Q-learning framework to achieve collaborative pushing and grasping.Specifically,an efficient non-maximum suppression policy(PolicyNMS)is proposed to dynamically evaluate pushing and grasping actions by enforcing a suppression constraint on unreasonable actions.Moreover,a novel data-driven pushing reward network called PR-Net is designed to effectively assess the degree of separation or aggregation between objects.To benchmark the proposed method,we establish a dataset containing common household items dataset(CHID)in both simulation and real scenarios.Although trained using simulation data only,experiment results validate that our method generalizes well to real scenarios and achieves a 97%grasp success rate at a fast speed for object separation in the real-world environment.
文摘BACKGROUND Endoscopic submucosal dissection(ESD)is widely accepted for early gastric cancer(EGC)without lymph node metastasis,although ESD is challenging,even for small lesions,in the greater curvature(GC)of the upper(U)and middle(M)thirds of the stomach.Grasping forceps-assisted endoscopic resection(GF-ER)is a type of endoscopic mucosal resection that is performed via a double-channel endoscope.AIM To investigate the safety and efficacy of GF-ER vs ESD in the GC of the stomach’s U and M regions.METHODS We retrospectively reviewed the medical records of 506 patients who underwent ER of 522 EGC lesions in the stomach’s U and M regions in three institutions between January 2016 and May 2020.Nine lesions from eight patients who underwent GF-ER for EGC(the GF-ER group)were compared to 63 lesions from 63 patients who underwent ESD(the ESD group).We also performed a subgroup analysis of small lesions(≤10 mm)in 6 patients(7 lesions)from the GF-ER group and 20 patients(20 lesions)from the ESD group.RESULTS There were no statistically significant differences between the GF-ER and ESD groups in the en bloc resection rates(100%vs 100%)and the R0 resection rates(100%vs 98.4%).The median procedure time in the GF-ER group was shorter than that in the ESD group(4.0 min vs 55.0 min,P<0.01).There were no adverse events in the GF-ER group,although five perforations(8.0%)and 1 case of postoperative bleeding(1.6%)were observed in the ESD group.When we only considered lesions that were≤10 mm,the median procedure time in the GF-ER group was still shorter than that in the ESD group(4.0 min vs 35.0 min,P<0.01).There were no adverse events in the GF-ER group,although 1 case of perforation(1.6%)were observed in the ESD group.CONCLUSION These findings suggest that GF-ER may be an effective therapeutic option for small lesions in the GC of the stomach’s U and M regions.
基金National Natural Science Foundation of China(No.52101346)Fundamental Research Funds for the Central Universities,China(No.2232019D3-61)Initial Research Fund for the Young Teachers of Donghua University,China。
文摘Robotic grasps play an important role in the service and industrial fields,and the robotic arm can grasp the object properly depends on the accuracy of the grasping detection result.In order to predict grasping detection positions for known or unknown objects by a modular robotic system,a convolutional neural network(CNN)with the residual block is proposed,which can be used to generate accurate grasping detection for input images of the scene.The proposed model architecture was trained on the standard Cornell grasp dataset and evaluated on the test dataset.Moreover,it was evaluated on different types of household objects and cluttered multi-objects.On the Cornell grasp dataset,the accuracy of the model on image-wise splitting detection and object-wise splitting detection achieved 95.5%and 93.6%,respectively.Further,the real detection time per image was 109 ms.The experimental results show that the model can quickly detect the grasping positions of a single object or multiple objects in image pixels in real time,and it keeps good stability and robustness.
文摘It is of great significance to have a clear understanding of the international environment that China faces. But this is an uneasy job. Since September 11, the world situation has become so complicated that it is hard to grasp its essence even with painstaking efforts. To judge such an already complicated international environment from China’s perspective adds more difficulties, for different people usually have different views due to the different angles from which they see the situation and different methods they adopt. This, understandably, leads to hot debates within the Chinese academic circles. To provide a stage for exchange of views, at the invitation of the CIR Expert Forum, some well-known scholars and experts on international relations from Beijing gathered to hold a symposium on November 5, 2002, with the theme of "How to assess the international environment that China faces". The speeches at the symposium are published in two installments. Following are the second half.
文摘Laparoscopic surgery is a new abdominal surgical procedure which helps the patients in many ways like less hospital stay, faster recovery and reduced pain. The main disadvantage in this surgical procedure is the reduced haptic perception by the surgeons due to the usage of laparoscopic instrument to handle tissues which in turn cause damage of it as compared to an open surgery. The primary aim of this investigation was to compare the pinch force applied during two different methods of laparoscopic grasping: Finger and Palm grasp. A low cost force sensing resistor tailor made for the grasper tip was designed and fabricated for quantifying the grasper tip force in the study. The results indicate more pinch force was applied during palm grasp as compared to finger grasp so as to prevent the slippage of the tissues from the jaws of the laparoscopic graspers.
文摘The current study examined the effects of band therapy using music on grasping power, depression, and personal relationships among residents of a nursing home. Thirty subjects participated in the study. The band therapy included greetings, warm-up exercises with music, singing with dance, playing instruments, closing speech, and stretching with background music. Band therapy was held for 40 minutes once per week, for a total of four sessions, in the activity room of the nursing home. Findings showed that grasping power, depression, and personal relationships were improved at posttest, but the differences were not statistically significant. A better study design to compare the effects of band therapy with the other group, and a more simple and repeated intervention for the elderly to follow without stress might be necessary.
文摘The Chinese government officially resumed its exercise of sovereignty over Hong Kong on July 1, 1997. On this historic occasion, the China National Machinery Import and Export Corporation officially renamed itself as the China Machinery Import and Export Group Corporation, with the approval of the relevant department of the state, and moved into its new office building. The change of name marks the progress it has achieved in a the course of exploring the establishment of a modern enterprise system. It was designated by the State Council in 1994 as one of the first group of 100 enterprises in China to introduce the modern enterprise system on a trial basis.In particular since 1995, when its
基金supported by the National Natural Science Foundation of China (Grant Nos.52275026 and 91948302)the State Key Laboratory of Structural Analysis for Industrial Equipment (Grant No.GZ21117)。
文摘The intrinsic compliance of soft materials endows soft robots with great advantages to achieve large deformation and adaptive interactions in grasping tasks.However,current soft grippers usually focus on the in-plane large deformation and load capacity but ignore the effect of out-of-plane external loads,which may lead to instability in practical scenarios.This problem calls for stiffness design along multiple directions to withstand not only in-plane interacting forces with objects,but also unexpected outof-plane loads.In this paper,we design a new type of soft finger by embedding an endoskeleton inside the widely-used PneuNets actuator,and the endoskeleton layout is optimized to achieve a remarkable bending deflection and limited lateral deflection under combined external in-plane and out-of-plane loads.Based on the multi-objective topology optimization approach,the key structural features of the optimized endoskeleton are extracted and parameterized.The multi-material soft fingers are fabricated by the silicone compound mold method.Static and dynamic experiment results validate that the soft gripper with endoskeleton embedded exhibits remarkably improved out-of-plane stiffness,without sacrificing the in-plane bending flexibility,and leads to more stable grasping.
基金Research was supported in part by the National Natural Science Foundation of China(No.62171473)Beijing Science and Technology Program(No.Z201100004420015)Fundamental Research Funds for the Central Universities of China(No.FRF-TP-20-017A1).
文摘Although notable progress has been made in the study of Steady-State Visual Evoked Potential(SSVEP)-based Brain-Computer Interface(BCI),several factors that limit the practical applications of BCIs still exist.One of these factors is the importability of the stimulator.In this study,Augmented Reality(AR)technology was introduced to present the visual stimuli of SSVEP-BCI,while the robot grasping experiment was designed to verify the applicability of the AR-BCI system.The offline experiment was designed to determine the best stimulus time,while the online experiment was used to complete the robot grasping task.The offline experiment revealed that better information transfer rate performance could be achieved when the stimulation time is 2 s.Results of the online experiment indicate that all 12 subjects could control the robot to complete the robot grasping task,which indicates the applicability of the AR-SSVEP-humanoid robot(NAO)system.This study verified the reliability of the AR-BCI system and indicated the applicability of the AR-SSVEP-NAO system in robot grasping tasks.
基金This was supported in part by the National Natural Science Foundation of China under Grant 52275027,52275028 and 52205028in part by the Tianjin Science and Technology Planning Project under Grant 20201193.
文摘Inspired by the morphology of human fingers,this paper proposes an underactuated rigid-soft coupled robotic gripper whose finger is designed as the combination of a rigid skeleton and a soft tissue.Different from the current grippers who have multi-point contact or line contact with the target objects,the proposed robotic gripper enables surface contact and leads to flexible grasping and robust holding.The actuated mechanism,which is the palm of proposed gripper,is optimized for excellent operability based on a mathematical model.Soft material selection and rigid skeleton structure of fingers are then analyzed through a series of dynamic simulations by RecurDyn and Adams.After above design process including topology analysis,actuated mechanism optimization,soft material selection and rigid skeleton analysis,the rigid-soft coupled robotic gripper is fabricated via 3D printing.Finally,the grasping and holding capabilities are validated by experiments testing the stiffness of a single finger and the impact resistance of the gripper.Experimental results show that the proposed rigid-soft coupled robotic gripper can adapt to objects with different properties(shape,size,weight and softness)and hold them steadily.It confirms the feasibility of the design procedure,as well as the compliant and dexterous grasping capabilities of proposed rigid-soft coupled gripper.
基金supported by the National Natural Science Foundation of China (Grant No.51975505)the Ningbo Natural Science Foundation of China (Grant No.2022J134)the Open Research Project of the State Key Laboratory of Industrial Control Technology,Zhejiang University,China (Grant No.ICT 2022B14)。
文摘Developing large,soft grippers with high omnidirectional load(above 40 kg)has always been challenging.We address this challenge by developing a powerful soft gripper that can grasp the human body based on a soft-enclosed grasping structure and a soft-rigid coupling structure.The envelope size of the proposed soft gripper is 611.6 mm×559 mm×490.7 mm,the maximum grasping size is 417 mm,and the payload on the human body is more than 90 kg,which has exceeded most existing soft grippers.Furthermore,the grasping force prediction of the gripper is achieved through theoretical modeling.The primary contribution of this work is to overcome the size and payload limits of current soft grippers and implement a human-grasping experiment based on the soft-grasping method.
基金supported in part by Natural Science Foundation Key projects of Hebei Province under Grant E2021203125in part by the Joint fund of the Science&Technology Department of Liaoning Province and State Key Laboratory of Robotics,China under Grant 2021KF2206+1 种基金in part by Local science and technology development fund projects guided by the central government under Grant 206Z1807Gin part by Hebei Province Graduate Innovation Funding Project under Grant CXZZBS2022127.
文摘To improve the grasping power of soft robots,inspired by the scene of intertwined and interdependent vine branches safely clinging to habitats in a violent storm and the phenomenon of large grasping force after being entangled by aquatic plants,this paper proposes a soft robotic gripper with multi-stem twining.The proposed robotic gripper can realize a larger contact area of surrounding or containing object and more layers of a twining object than the current twining gripping methods.It not only retains the adaptive advantages of twining grasping but also improves the grasping force.First,based on the mechanical characteristics of the multi-stem twining of the gripper,the twining grasping model is developed.Then,the force on the fiber is deduced by using the twining theory,and the axial force of the gripper is analyzed based on the equivalent model of the rubber ring.Finally,the torsion experiments of fibers and the grasping experiments of the gripper are designed and conducted.The torsion experiment of fibers verifies the influence of a different number of fiber ropes and fiber torque on the grasping force,and the grasping experiment reflects the large load of the gripper and the high adaptability and practicability under different tasks.
基金This work was funded by the National Natural Science Foundation of Chinaunder Grant 62073305the Fundamental Research Funds for the Central Universities,China University of Geosciences(Wuhan)(Nos.CUG170610 and CUGGC02).
文摘In this paper,we propose a fully Soft Bionic Grasping Device(SBGD),which has advantages in automatically adjusting the grasping range,variable stiffness,and controllable bending shape.This device consists of soft gripper structures and a soft bionic bracket structure.We adopt the local thin-walled design in the soft gripper structures.This design improves the grippers’bending efficiency,and imitate human finger’s segmental bending function.In addition,this work also proposes a pneumatic soft bionic bracket structure,which not only can fix grippers,but also can automatically adjust the grasping space by imitating the human adjacent fingers’opening and closing movements.Due to the above advantages,the SBGD can grasp larger or smaller objects than the regular grasping devices.Particularly,to grasp small objects reliably,we further present a new Pinching Grasping(PG)method.The great performance of the fully SBGD is verified by experiments.This work will promote innovative development of the soft bionic grasping robots,and greatly meet the applications of dexterous grasping multi-size and multi-shape objects.
基金supported by the Beijing Innovation Consortium of Agriculture Research System (BAIC12).
文摘The application of robotic grasping for agricultural products pushes automation in agriculture-related industries.Cucumber,a common vegetable in greenhouses and supermarkets,often needs to be grasped from a cluttered scene.In order to realize efficient grasping in cluttered scenes,a fully automatic cucumber recognition,grasping,and palletizing robot system was constructed in this paper.The system adopted Yolact++deep learning network to segment cucumber instances.An early fusion method of F-RGBD was proposed,which increases the algorithm's discriminative ability for these appearance-similar cucumbers at different depths,and at different occlusion degrees.The results of the comparative experiment of the F-RGBD dataset and the common RGB dataset on Yolact++prove the positive effect of the F-RGBD fusion method.Its segmentation masks have higher quality,are more continuous,and are less false positive for prioritizing-grasping prediction.Based on the segmentation result,a 4D grab line prediction method was proposed for cucumber grasping.And the cucumber detection experiment in cluttered scenarios is carried out in the real world.The success rate is 93.67%and the average sorting time is 9.87 s.The effectiveness of the cucumber segmentation and grasping pose acquisition method is verified by experiments.
