Plants are usually considered static organisms,but they can perform a wide range of movements that can be a source of inspiration for robots.The roots’growing motion is the most noteworthy since they are excellent di...Plants are usually considered static organisms,but they can perform a wide range of movements that can be a source of inspiration for robots.The roots’growing motion is the most noteworthy since they are excellent diggers that can move in unstructured environments and navigate past barriers.Furthermore,root growth has a high energy efficiency since it penetrates the soil at its tip,adding new material without displacing the already grown portion,minimizing the energy dissipation due to friction and lowering the inertia.A robot inspired by the growth of roots could be used in search and rescue or environmental monitoring.The design of a soft robot inspired by root growth is presented in this article.The robot body consists of a cylindrical plastic membrane folded inside itself.The robot body is inflated,and its tip is everted,expanding its length as air is blown from the base.Velcro straps are placed on the membrane’s exterior surface to keep it folded.The head is positioned inside the tip,which houses the mechanism that controls the growth direction.It consists of housing for two balloons that are selectively inflated,and their expansion applies pressure on the exterior surface,opening the Velcro straps and determining the growth direction.The robot was constructed,and a kinematic model of its motion in the plane was created and compared with experimental data.The error in predicting the turning angle is only 5%,and the resulting predicted position differs on average by 55 mm on a total length of 850 mm.展开更多
In this study,we present a small,integrated jumping-crawling robot capable of intermittent jumping and self-resetting.Compared to robots with a single mode of locomotion,this multi-modal robot exhibits enhanced obstac...In this study,we present a small,integrated jumping-crawling robot capable of intermittent jumping and self-resetting.Compared to robots with a single mode of locomotion,this multi-modal robot exhibits enhanced obstacle-surmounting capabilities.To achieve this,the robot employs a novel combination of a jumping module and a crawling module.The jumping module features improved energy storage capacity and an active clutch.Within the constraints of structural robustness,the jumping module maximizes the explosive power of the linear spring by utilizing the mechanical advantage of a closed-loop mechanism and controls the energy flow of the jumping module through an active clutch mechanism.Furthermore,inspired by the limb movements of tortoises during crawling and self-righting,a single-degree-of-freedom spatial four-bar crawling mechanism was designed to enable crawling,steering,and resetting functions.To demonstrate its practicality,the integrated jumping-crawling robot was tested in a laboratory environment for functions such as jumping,crawling,self-resetting,and steering.Experimental results confirmed the feasibility of the proposed integrated jumping-crawling robot.展开更多
Autonomous legged robots,capable of navigating uneven terrain,can perform a diverse array of tasks.However,designing locomotion controllers remains challenging.In particular,designing a controller based on durable and...Autonomous legged robots,capable of navigating uneven terrain,can perform a diverse array of tasks.However,designing locomotion controllers remains challenging.In particular,designing a controller based on durable and reliable proprioceptive sensors,is essential for achieving adaptability.Presently,the controller must either be manually designed for specific robots and tasks,or developed using machine-learning techniques,which require extensive training time and result in complex controllers.Inspired by animal locomotion,we propose a simple yet comprehensive closed-loop modular framework that utilizes minimal proprioceptive feedback(i.e.,the Coxa-Femur(CF)joint angle),enabling a quadruped robot to efficiently navigate unpredictable and uneven terrains,including the step and slope.The framework comprises a basic neural control network capable of rapidly learning optimized motor patterns,and a straightforward module for sensory feedback sharing and integration.In a series of experiments,we show that integrating sensory feedback into the base neural control network aids the robot in continually learning robust motor patterns on flat,step,and slope terrain,compared with the open-loop base framework.Sharing sensory feedback information across the four legs enables a quadruped robot to proactively navigate unpredictable steps with minimal interaction.Furthermore,the controller remains functional even in the absence of sensor signals.This control configuration was successfully transferred to a physical robot without any modifications.展开更多
During marine missions,AUVs are susceptible to external disturbances,such as obstacles,ocean currents,etc.,which can easily cause mission failure or disconnection.In this paper,considering the strong nonlinearities,ex...During marine missions,AUVs are susceptible to external disturbances,such as obstacles,ocean currents,etc.,which can easily cause mission failure or disconnection.In this paper,considering the strong nonlinearities,external disturbances and obstacles,the kinematic and dynamic model of bioinspired Spherical Underwater Robot(SUR)was described.Subsequently,the waypoints-based trajectory tracking with obstacles and uncertainties was proposed for SUR to guarantee its safety and stability.Next,the Lyapunov theory was adopted to verify the stability and the Slide Mode Control(SMC)method is used to verify the robustness of the control system.In addition,a series of simulations were conducted to evaluate the effectiveness of proposed control strategy.Some tests,including path-following,static and moving obstacle avoidance were performed which verified the feasibility,robustness and effectiveness of the designed control scheme.Finally,a series of experiments in real environment were performed to verify the performance of the control strategy.The simulation and experimental results of the study supplied clues to the improvement of the path following capability and multi-obstacle avoidance of AUVs.展开更多
It is common for robotic fish to generate thrust using reactive force generated by the tail’s physical motion, which interacts with the surrounding fluid. The coupling effect of the body strongly correlates with this...It is common for robotic fish to generate thrust using reactive force generated by the tail’s physical motion, which interacts with the surrounding fluid. The coupling effect of the body strongly correlates with this thrust. However, hydrodynamics cannot be wholly modeled in analytical form. Therefore, data-assisted modeling is necessary for robotic fish. This work presents the first method of its kind using Genetic Algorithm (GA)-based optimization methods for data-assistive modeling for robotic fish applications. To begin, experimental data are collected in real time with the robotic fish that has been designed and fabricated using 3D printing. Then, the model’s influential parameters are estimated using an optimization problem. Further, a model-based deep reinforcement learning (DRL) controller is proposed to track the desired speed through extensive simulation work. In addition to a deep deterministic policy gradient (DDPG), a twin delayed DDPG (TD3) is employed in the training of the RL agent. Unfortunately, due to its local optimization problem, the RL-DDPG controller failed to perform well during training. In contrast, the RL-TD3 controller effectively learns the control policies and overcomes the local optima problem. As a final step, controller performance is evaluated under different disturbance conditions. In contrast to DDPG and GA-tuned proportional-integral controllers, the proposed model with RL-TD3 controller significantly improves the performance.展开更多
In recent years,more and more creatures in nature have become the source of inspiration for people to study bionic soft robots.Many such robots appear in the public’s vision.In this paper,a Venus flytrap robot simila...In recent years,more and more creatures in nature have become the source of inspiration for people to study bionic soft robots.Many such robots appear in the public’s vision.In this paper,a Venus flytrap robot similar to the biological Venus flytrap in appearance was designed and prepared.It was mainly cast by Polydimethylsiloxane(PDMs)and driven by the flexible material of Ionic Polymer Metal Composites(IPMCs).Combining with ANSYS and related experiments,the appropriate voltage and the size of IPMC were determined.The results showed that the performance of the Venus flytrap robot was the closest to the biological Venus flytrap when the size of IPMC length,width and driving voltage reach to 3 cm,1 cm and 5.5 V,respectively.Moreover,the closing speed and angle reached 8.22°/s and 37°,respectively.Finally,the fly traps also could be opened and closed repeatedly and captured a small ball with a mass of 0.3 g firmly in its middle and tip.展开更多
Soft actuators have garnered substantial attention in current years in view of their potential appliances in diverse domains like robotics,biomedical devices,and biomimetic systems.These actuators mimic the natural mo...Soft actuators have garnered substantial attention in current years in view of their potential appliances in diverse domains like robotics,biomedical devices,and biomimetic systems.These actuators mimic the natural movements of living organisms,aiming to attain enhanced flexibility,adaptability,and versatility.On the other hand,angle-independent structural color has been achieved through innovative design strategies and engineering approaches.By carefully controlling the size,shape,and arrangement of nanostructures,researchers have been able to create materials exhibiting consistent colors regardless of the viewing angle.One promising class of materials that holds great potential for bioinspired soft actuators is MXenes in view of their exceptional mechanical,electrical,and optical properties.The integration of MXenes for bioinspired soft actuators with angle-independent structural color offers exciting possibilities.Overcoming material compatibility issues,improving color reproducibility,scalability,durability,power supply efficiency,and cost-effectiveness will play vital roles in advancing these technologies.This perspective appraises the development of bioinspired MXene-centered soft actuators with angleindependent structural color in soft robotics.展开更多
In nature,organisms widely use the interaction of muscle contraction and biological pipelines to form an efficient fluid control mechanism.Herein,a pneumatically powered,Bioinspired Soft Switching valve(BSS valve)with...In nature,organisms widely use the interaction of muscle contraction and biological pipelines to form an efficient fluid control mechanism.Herein,a pneumatically powered,Bioinspired Soft Switching valve(BSS valve)with short response time and low-energy consumption is described.The BSS valve is composed of flexible walls,a flexible tube and symmetrically arranged Snapping Membrane actuator(SM actuator).It functions based on tube deformation throttling caused by instability of SM actuator membrane.To realize rapid preparation of customized BSS valve,the modular manufacturing method suitable for different materials and structures based on 3D printing and mold forming was developed.Using the membrane flip rate as indicators,the displacement transient response characteristics of three structures actuators were studied,The results proved that spherical and spherical cap membrane SM actuator achieved rapid displacement response under the low critical pressure threshold.Furthermore,with critical buckling pressure and capacity utilization efficiency as indicators,we analyzed the characteristics of SM actuators with different radius and wall thickness to obtain reasonable structural parameters configuration of SM actuators.The influence of radius and thickness on SM actuator is revealed,and theoretical model formulas were formed.Two different configurations are presented.(1)Customized BSS valve structures can achieve sequential motion of flexible gripper.(2)BSS valve embedded in soft pump.The performance tests confirmed it has significant advantages in energy consumption,specific pressure,specific flow,high-frequency cycle load life,and valve can be integrated into the soft pump fluid system as a throttling unit,and provides an idea for fluid drive control integration.展开更多
Moles exhibit highly effective capabilities due to their unique body structures and digging techniques,making them ideal models for biomimetic research.However,a major challenge for mole-inspired robots lies in overco...Moles exhibit highly effective capabilities due to their unique body structures and digging techniques,making them ideal models for biomimetic research.However,a major challenge for mole-inspired robots lies in overcoming resistance in granular media when burrowing with forelimbs.In the absence of effective forepaw design strategies,most robotic designs rely on increased power to enhance performance.To address this issue,this paper employs Resistive Force Theory to optimize mole-inspired forepaws,aiming to enhance burrowing efficiency.By analyzing the relationship between geometric parameters and burrowing forces,we propose several forepaw design variations.Through granular resistance assessments,an effective forepaw configuration is identified and further refined using parameters such as longitudinal and transverse curvature.Subsequently,the Particle Swarm Optimization algorithm is applied to determine the optimal forepaw design.In force-loading tests,the optimized forepaw demonstrated a 79.44%reduction in granular lift force and a 22.55%increase in propulsive force compared with the control group.In robotic burrowing experiments,the optimized forepaw achieved the longest burrow displacement(179.528 mm)and the lowest burrowing lift force(0.9355 mm/s),verifying its effectiveness in reducing the lift force and enhancing the propulsive force.展开更多
This paper presents a continuum manipulator inspired by the anatomical characteristics of the elephant trunk.Specifically,the manipulator mimics the conoid profile of the elephant trunk,which helps to enhance its stre...This paper presents a continuum manipulator inspired by the anatomical characteristics of the elephant trunk.Specifically,the manipulator mimics the conoid profile of the elephant trunk,which helps to enhance its strength.The design features two concentric parts:inner pneumatically actuated bellows and an outer tendon-driven helical spring.The tendons control the omnidirectional bending of the manipulator,while the fusion of the pneumatic bellows with the tendon-driven spring results in an antagonistic actuation mechanism that provides the manipulator with variable stiffness and extensibility.This paper presents a new design for extensible manipulator and analyzes its stiffness and motion characteristics.Experimental results are consistent with theoretical analysis,thereby demonstrating the validity of the theoretical approach and the versatile practical mechanical properties of the continuum manipulator.The impressive extensibility and variable stiffness of the manipulator were further demonstrated by performing a pin-hole assembly task.展开更多
In the field of robotics and visual-based navigation,event cameras are gaining popularity due to their exceptional dynamic range,low power consumption,and rapid response capabilities.These neuromorphic devices facilit...In the field of robotics and visual-based navigation,event cameras are gaining popularity due to their exceptional dynamic range,low power consumption,and rapid response capabilities.These neuromorphic devices facilitate the efficient detection and avoidance of fast moving obstacles,and address common limitations of traditional hardware.However,the majority of state-of-the-art event-based algorithms still rely on conven-tional computer vision strategies.The goal is to shift from the standard protocols for dynamic obstacle detection by taking inspiration from the time-computational paradigm of biological vision system.In this paper,the authors present an innovative framework inspired by a biological response mechanism triggered by approaching objects,enabling the perception and identification of potential collision threats.The method,validated through both simulation and real-world experimentation,charts a new path in the application of event cameras for dynamic obstacle detection and avoidance in autono-mous unmanned aerial vehicles.When compared to conventional methods,the proposed approach demonstrates a success rate of 97%in detecting obstacles within real-world outdoor settings.展开更多
The one-degree-of-freedom(DOF) mechanism has a simple structure, convenient control, and high stiffness, and it has been applied in many micro jumping robots. Meanwhile, the six-and eight-bar mechanisms can satisfy mo...The one-degree-of-freedom(DOF) mechanism has a simple structure, convenient control, and high stiffness, and it has been applied in many micro jumping robots. Meanwhile, the six-and eight-bar mechanisms can satisfy more complex motion requirements than the four-bar jumping leg mechanism and they have good application prospects. However, the lack of effective design methods limits the application range of these mechanisms. In this work, a type and dimensional integration synthesis method was proposed with the one-DOF six-bar leg mechanism as the research object. The initial tibia and femur were determined based on the kinematic chain atlas, and configuration design was implemented through the superposition of links.When a closed chain was formed in the superposition process, the feasible range of the link length was analyzed by considering the constraint conditions. The proposed method innovatively establishes the relationship between the kinematic chain atlas and the configuration, and the feasible length ranges of the links can be quickly obtained simultaneously. Several examples were provided to prove the feasibility of the kinematic synthesis method. This method provides a useful reference for the design of one-DOF mechanisms.展开更多
The earthworm-like robot is designed for prospective applications such as disaster rescue and pipeline detection in natural environments.However,current studies on the interaction modeling between the earthworm-like r...The earthworm-like robot is designed for prospective applications such as disaster rescue and pipeline detection in natural environments.However,current studies on the interaction modeling between the earthworm-like robot and the environment only consider rigid contact.This simplification limits the reliability of dynamic analysis and locomotion optimization on soft surfaces,such as sand.Therefore,developing a method for refined contact modeling for the earthworm-like robot and describing the contact effect induced by the soft environmental medium is urgent.To this end,this paper proposes a new modeling architecture called the elementary mechanical network(EMN).EMN is constructed as fractal structures for the convenience of network reconfiguration.First,elementary mechanical elements,such as the damper,spring,and slider,are parallelly connected to constitute a basic module.Second,the modules are serially linked to create a group.Finally,the groups are parallelly assembled to form the network.EMN is also proven to be equivalent to recurrent neural networks in specific forms.Therefore,EMN inherits the advantages of physical interpretability from mechanical elements and universal approximability from conventional networks.In addition,particle swarm optimization and Boolean operation are employed for network weight training and topological minimization.Numerical examples show that using EMNs with identical initial structures can accurately describe diverse empirical models in the minimum realization.EMN is applied for contact modeling for the earthworm-like locomotion robot in the dry sand based on such versatility.The experiment measures the normal and tangential ground reaction forces with different sinkage depths and locomotion speeds.Trained results reveal a common law that the contact effect in the dry sand is similar to Coulomb friction.The proposed EMN does not require prior system knowledge and promises a minimal physical representation,thus encouraging a successful exploration of constitutive modeling in broad scopes.展开更多
文摘Plants are usually considered static organisms,but they can perform a wide range of movements that can be a source of inspiration for robots.The roots’growing motion is the most noteworthy since they are excellent diggers that can move in unstructured environments and navigate past barriers.Furthermore,root growth has a high energy efficiency since it penetrates the soil at its tip,adding new material without displacing the already grown portion,minimizing the energy dissipation due to friction and lowering the inertia.A robot inspired by the growth of roots could be used in search and rescue or environmental monitoring.The design of a soft robot inspired by root growth is presented in this article.The robot body consists of a cylindrical plastic membrane folded inside itself.The robot body is inflated,and its tip is everted,expanding its length as air is blown from the base.Velcro straps are placed on the membrane’s exterior surface to keep it folded.The head is positioned inside the tip,which houses the mechanism that controls the growth direction.It consists of housing for two balloons that are selectively inflated,and their expansion applies pressure on the exterior surface,opening the Velcro straps and determining the growth direction.The robot was constructed,and a kinematic model of its motion in the plane was created and compared with experimental data.The error in predicting the turning angle is only 5%,and the resulting predicted position differs on average by 55 mm on a total length of 850 mm.
基金supported by the National Natural Science Foundation of China(Nos.51375383).
文摘In this study,we present a small,integrated jumping-crawling robot capable of intermittent jumping and self-resetting.Compared to robots with a single mode of locomotion,this multi-modal robot exhibits enhanced obstacle-surmounting capabilities.To achieve this,the robot employs a novel combination of a jumping module and a crawling module.The jumping module features improved energy storage capacity and an active clutch.Within the constraints of structural robustness,the jumping module maximizes the explosive power of the linear spring by utilizing the mechanical advantage of a closed-loop mechanism and controls the energy flow of the jumping module through an active clutch mechanism.Furthermore,inspired by the limb movements of tortoises during crawling and self-righting,a single-degree-of-freedom spatial four-bar crawling mechanism was designed to enable crawling,steering,and resetting functions.To demonstrate its practicality,the integrated jumping-crawling robot was tested in a laboratory environment for functions such as jumping,crawling,self-resetting,and steering.Experimental results confirmed the feasibility of the proposed integrated jumping-crawling robot.
基金supported by the National Natural Science Foundation of China(Grant Nos.62233008 and 51705247)the State Key Laboratory of Mechanics and Control for Aerospace Structures of Nanjing University of Aeronautics and Astronautics.
文摘Autonomous legged robots,capable of navigating uneven terrain,can perform a diverse array of tasks.However,designing locomotion controllers remains challenging.In particular,designing a controller based on durable and reliable proprioceptive sensors,is essential for achieving adaptability.Presently,the controller must either be manually designed for specific robots and tasks,or developed using machine-learning techniques,which require extensive training time and result in complex controllers.Inspired by animal locomotion,we propose a simple yet comprehensive closed-loop modular framework that utilizes minimal proprioceptive feedback(i.e.,the Coxa-Femur(CF)joint angle),enabling a quadruped robot to efficiently navigate unpredictable and uneven terrains,including the step and slope.The framework comprises a basic neural control network capable of rapidly learning optimized motor patterns,and a straightforward module for sensory feedback sharing and integration.In a series of experiments,we show that integrating sensory feedback into the base neural control network aids the robot in continually learning robust motor patterns on flat,step,and slope terrain,compared with the open-loop base framework.Sharing sensory feedback information across the four legs enables a quadruped robot to proactively navigate unpredictable steps with minimal interaction.Furthermore,the controller remains functional even in the absence of sensor signals.This control configuration was successfully transferred to a physical robot without any modifications.
基金supported in part by the National Natural Science Foundation of China under Grant 61703305,in part by the National High TechResearch and Development Program(863 Program)of China under Grant 2015AA043202+3 种基金in part by the Japan Society for the Promotion of Science(SPS)KAKENHI under Grant 15K2120in part by the Key Research Program of the Natural Science Foundation of Tianjin under Grant 18JCZDJC38500in part by the Innovative Cooperation Project of Tianjin Scientific and Technological Support under Grant 18PTZWHZ00090in part by the China Scholarship Council(CSC)for his doctoral research at Kagawa University under Grant 202208050040.
文摘During marine missions,AUVs are susceptible to external disturbances,such as obstacles,ocean currents,etc.,which can easily cause mission failure or disconnection.In this paper,considering the strong nonlinearities,external disturbances and obstacles,the kinematic and dynamic model of bioinspired Spherical Underwater Robot(SUR)was described.Subsequently,the waypoints-based trajectory tracking with obstacles and uncertainties was proposed for SUR to guarantee its safety and stability.Next,the Lyapunov theory was adopted to verify the stability and the Slide Mode Control(SMC)method is used to verify the robustness of the control system.In addition,a series of simulations were conducted to evaluate the effectiveness of proposed control strategy.Some tests,including path-following,static and moving obstacle avoidance were performed which verified the feasibility,robustness and effectiveness of the designed control scheme.Finally,a series of experiments in real environment were performed to verify the performance of the control strategy.The simulation and experimental results of the study supplied clues to the improvement of the path following capability and multi-obstacle avoidance of AUVs.
文摘It is common for robotic fish to generate thrust using reactive force generated by the tail’s physical motion, which interacts with the surrounding fluid. The coupling effect of the body strongly correlates with this thrust. However, hydrodynamics cannot be wholly modeled in analytical form. Therefore, data-assisted modeling is necessary for robotic fish. This work presents the first method of its kind using Genetic Algorithm (GA)-based optimization methods for data-assistive modeling for robotic fish applications. To begin, experimental data are collected in real time with the robotic fish that has been designed and fabricated using 3D printing. Then, the model’s influential parameters are estimated using an optimization problem. Further, a model-based deep reinforcement learning (DRL) controller is proposed to track the desired speed through extensive simulation work. In addition to a deep deterministic policy gradient (DDPG), a twin delayed DDPG (TD3) is employed in the training of the RL agent. Unfortunately, due to its local optimization problem, the RL-DDPG controller failed to perform well during training. In contrast, the RL-TD3 controller effectively learns the control policies and overcomes the local optima problem. As a final step, controller performance is evaluated under different disturbance conditions. In contrast to DDPG and GA-tuned proportional-integral controllers, the proposed model with RL-TD3 controller significantly improves the performance.
基金financial assistance from the Key Laboratory Project of Expressway Construction Machinery of Shaanxi Province,China(300102259510)the Key Research and Development Program of Shaanxi Province,China(2018ZDXM-GY-088)+1 种基金Analysis and compensation friction error of inclined installation feed system for NC machine tools,China(17JK0509)Study on mechanism and suppression strategy of friction error for CNC machine tools,China(2017JM5042).
文摘In recent years,more and more creatures in nature have become the source of inspiration for people to study bionic soft robots.Many such robots appear in the public’s vision.In this paper,a Venus flytrap robot similar to the biological Venus flytrap in appearance was designed and prepared.It was mainly cast by Polydimethylsiloxane(PDMs)and driven by the flexible material of Ionic Polymer Metal Composites(IPMCs).Combining with ANSYS and related experiments,the appropriate voltage and the size of IPMC were determined.The results showed that the performance of the Venus flytrap robot was the closest to the biological Venus flytrap when the size of IPMC length,width and driving voltage reach to 3 cm,1 cm and 5.5 V,respectively.Moreover,the closing speed and angle reached 8.22°/s and 37°,respectively.Finally,the fly traps also could be opened and closed repeatedly and captured a small ball with a mass of 0.3 g firmly in its middle and tip.
文摘Soft actuators have garnered substantial attention in current years in view of their potential appliances in diverse domains like robotics,biomedical devices,and biomimetic systems.These actuators mimic the natural movements of living organisms,aiming to attain enhanced flexibility,adaptability,and versatility.On the other hand,angle-independent structural color has been achieved through innovative design strategies and engineering approaches.By carefully controlling the size,shape,and arrangement of nanostructures,researchers have been able to create materials exhibiting consistent colors regardless of the viewing angle.One promising class of materials that holds great potential for bioinspired soft actuators is MXenes in view of their exceptional mechanical,electrical,and optical properties.The integration of MXenes for bioinspired soft actuators with angle-independent structural color offers exciting possibilities.Overcoming material compatibility issues,improving color reproducibility,scalability,durability,power supply efficiency,and cost-effectiveness will play vital roles in advancing these technologies.This perspective appraises the development of bioinspired MXene-centered soft actuators with angleindependent structural color in soft robotics.
基金supported by the National Natural Science Foundation of China(nos.52075216,91948302,and 91848204).
文摘In nature,organisms widely use the interaction of muscle contraction and biological pipelines to form an efficient fluid control mechanism.Herein,a pneumatically powered,Bioinspired Soft Switching valve(BSS valve)with short response time and low-energy consumption is described.The BSS valve is composed of flexible walls,a flexible tube and symmetrically arranged Snapping Membrane actuator(SM actuator).It functions based on tube deformation throttling caused by instability of SM actuator membrane.To realize rapid preparation of customized BSS valve,the modular manufacturing method suitable for different materials and structures based on 3D printing and mold forming was developed.Using the membrane flip rate as indicators,the displacement transient response characteristics of three structures actuators were studied,The results proved that spherical and spherical cap membrane SM actuator achieved rapid displacement response under the low critical pressure threshold.Furthermore,with critical buckling pressure and capacity utilization efficiency as indicators,we analyzed the characteristics of SM actuators with different radius and wall thickness to obtain reasonable structural parameters configuration of SM actuators.The influence of radius and thickness on SM actuator is revealed,and theoretical model formulas were formed.Two different configurations are presented.(1)Customized BSS valve structures can achieve sequential motion of flexible gripper.(2)BSS valve embedded in soft pump.The performance tests confirmed it has significant advantages in energy consumption,specific pressure,specific flow,high-frequency cycle load life,and valve can be integrated into the soft pump fluid system as a throttling unit,and provides an idea for fluid drive control integration.
基金financially supported in-part by the National Natural Science Foundation of China(52275011)the Natural Science Foundation of Guangdong Province(2023B1515020080)+3 种基金the Natural Science Foundation of Guangzhou(2024A04J2552)the Fundamental Research Funds for the Central Universities,the Young Elite Scientists Sponsorship Program by the China Association for Science and Technology(CAST)(2021QNRC001)the Guangdong Basic and Applied Basic Research Foundation(Grant No.2023A1515011253)the Higher Education Institution Featured Innovation Project of Department of Education of Guangdong Province(GrantNo.2023KTSCX138).
文摘Moles exhibit highly effective capabilities due to their unique body structures and digging techniques,making them ideal models for biomimetic research.However,a major challenge for mole-inspired robots lies in overcoming resistance in granular media when burrowing with forelimbs.In the absence of effective forepaw design strategies,most robotic designs rely on increased power to enhance performance.To address this issue,this paper employs Resistive Force Theory to optimize mole-inspired forepaws,aiming to enhance burrowing efficiency.By analyzing the relationship between geometric parameters and burrowing forces,we propose several forepaw design variations.Through granular resistance assessments,an effective forepaw configuration is identified and further refined using parameters such as longitudinal and transverse curvature.Subsequently,the Particle Swarm Optimization algorithm is applied to determine the optimal forepaw design.In force-loading tests,the optimized forepaw demonstrated a 79.44%reduction in granular lift force and a 22.55%increase in propulsive force compared with the control group.In robotic burrowing experiments,the optimized forepaw achieved the longest burrow displacement(179.528 mm)and the lowest burrowing lift force(0.9355 mm/s),verifying its effectiveness in reducing the lift force and enhancing the propulsive force.
基金supported by the National Key R&D Program of China(No.2018YFB1305400)the Major Research Plan of the National Natural Science Foundation of China(No.92048301)+1 种基金the National Natural Science Foundation of China(No.52025054)the Joint Research Fund between the National Natural Science Foundation of China(NSFC)and Shen Zhen(No.U1713201).
文摘This paper presents a continuum manipulator inspired by the anatomical characteristics of the elephant trunk.Specifically,the manipulator mimics the conoid profile of the elephant trunk,which helps to enhance its strength.The design features two concentric parts:inner pneumatically actuated bellows and an outer tendon-driven helical spring.The tendons control the omnidirectional bending of the manipulator,while the fusion of the pneumatic bellows with the tendon-driven spring results in an antagonistic actuation mechanism that provides the manipulator with variable stiffness and extensibility.This paper presents a new design for extensible manipulator and analyzes its stiffness and motion characteristics.Experimental results are consistent with theoretical analysis,thereby demonstrating the validity of the theoretical approach and the versatile practical mechanical properties of the continuum manipulator.The impressive extensibility and variable stiffness of the manipulator were further demonstrated by performing a pin-hole assembly task.
文摘In the field of robotics and visual-based navigation,event cameras are gaining popularity due to their exceptional dynamic range,low power consumption,and rapid response capabilities.These neuromorphic devices facilitate the efficient detection and avoidance of fast moving obstacles,and address common limitations of traditional hardware.However,the majority of state-of-the-art event-based algorithms still rely on conven-tional computer vision strategies.The goal is to shift from the standard protocols for dynamic obstacle detection by taking inspiration from the time-computational paradigm of biological vision system.In this paper,the authors present an innovative framework inspired by a biological response mechanism triggered by approaching objects,enabling the perception and identification of potential collision threats.The method,validated through both simulation and real-world experimentation,charts a new path in the application of event cameras for dynamic obstacle detection and avoidance in autono-mous unmanned aerial vehicles.When compared to conventional methods,the proposed approach demonstrates a success rate of 97%in detecting obstacles within real-world outdoor settings.
基金supported by the National Natural Science Foundation of China(Grant No. 51805010)General Project of Beijing Education Commission(Grant No. KM201910005032)China Postdoctoral Science Foundation(Grant No. 2018M630051)
文摘The one-degree-of-freedom(DOF) mechanism has a simple structure, convenient control, and high stiffness, and it has been applied in many micro jumping robots. Meanwhile, the six-and eight-bar mechanisms can satisfy more complex motion requirements than the four-bar jumping leg mechanism and they have good application prospects. However, the lack of effective design methods limits the application range of these mechanisms. In this work, a type and dimensional integration synthesis method was proposed with the one-DOF six-bar leg mechanism as the research object. The initial tibia and femur were determined based on the kinematic chain atlas, and configuration design was implemented through the superposition of links.When a closed chain was formed in the superposition process, the feasible range of the link length was analyzed by considering the constraint conditions. The proposed method innovatively establishes the relationship between the kinematic chain atlas and the configuration, and the feasible length ranges of the links can be quickly obtained simultaneously. Several examples were provided to prove the feasibility of the kinematic synthesis method. This method provides a useful reference for the design of one-DOF mechanisms.
基金supported by the National Natural Science Foundation of China (Grant Nos.11932015 and 11902077)the Shanghai Sailing Program(Grant No.19YF1403000)the Science and Technology Commission of Shanghai Municipality (Grant No.19511132000)。
文摘The earthworm-like robot is designed for prospective applications such as disaster rescue and pipeline detection in natural environments.However,current studies on the interaction modeling between the earthworm-like robot and the environment only consider rigid contact.This simplification limits the reliability of dynamic analysis and locomotion optimization on soft surfaces,such as sand.Therefore,developing a method for refined contact modeling for the earthworm-like robot and describing the contact effect induced by the soft environmental medium is urgent.To this end,this paper proposes a new modeling architecture called the elementary mechanical network(EMN).EMN is constructed as fractal structures for the convenience of network reconfiguration.First,elementary mechanical elements,such as the damper,spring,and slider,are parallelly connected to constitute a basic module.Second,the modules are serially linked to create a group.Finally,the groups are parallelly assembled to form the network.EMN is also proven to be equivalent to recurrent neural networks in specific forms.Therefore,EMN inherits the advantages of physical interpretability from mechanical elements and universal approximability from conventional networks.In addition,particle swarm optimization and Boolean operation are employed for network weight training and topological minimization.Numerical examples show that using EMNs with identical initial structures can accurately describe diverse empirical models in the minimum realization.EMN is applied for contact modeling for the earthworm-like locomotion robot in the dry sand based on such versatility.The experiment measures the normal and tangential ground reaction forces with different sinkage depths and locomotion speeds.Trained results reveal a common law that the contact effect in the dry sand is similar to Coulomb friction.The proposed EMN does not require prior system knowledge and promises a minimal physical representation,thus encouraging a successful exploration of constitutive modeling in broad scopes.
