Perception and manipulation tasks for robotic manipulators involving highly-cluttered objects have become increasingly indemand for achieving a more efficient problem solving method in modern industrial environments.B...Perception and manipulation tasks for robotic manipulators involving highly-cluttered objects have become increasingly indemand for achieving a more efficient problem solving method in modern industrial environments.But,most of the available methods for performing such cluttered tasks failed in terms of performance,mainly due to inability to adapt to the change of the environment and the handled objects.Here,we propose a new,near real-time approach to suction-based grasp point estimation in a highly cluttered environment by employing an affordance-based approach.Compared to the state-of-the-art,our proposed method offers two distinctive contributions.First,we use a modified deep neural network backbone for the input of the semantic segmentation,to classify pixel elements of the input red,green,blue and depth(RGBD)channel image which is then used to produce an affordance map,a pixel-wise probability map representing the probability of a successful grasping action in those particular pixel regions.Later,we incorporate a high speed semantic segmentation to the system,which makes our solution have a lower computational time.This approach does not need to have any prior knowledge or models of the objects since it removes the step of pose estimation and object recognition entirely compared to most of the current approaches and uses an assumption to grasp first then recognize later,which makes it possible to have an object-agnostic property.The system was designed to be used for household objects,but it can be easily extended to any kind of objects provided that the right dataset is used for training the models.Experimental results show the benefit of our approach which achieves a precision of 88.83%,compared to the 83.4%precision of the current state-of-the-art.展开更多
This paper proposed an autonomous planning,navigation and control framework for lightweight unmanned aerial vehicles(UAVs)in obstacle-dense environments with limited computational resources.The framework employed a po...This paper proposed an autonomous planning,navigation and control framework for lightweight unmanned aerial vehicles(UAVs)in obstacle-dense environments with limited computational resources.The framework employed a polynomial-based minimum-snap trajectory generation method to ensure obstacle-free in confined three-dimensional(3D)spaces.A gradient-based trajectory optimization strategy integrated smoothness constraints,collision avoidance and dynamic feasibility was proposed to ensure safety and motion smoothness.The model predictive control(MPC)method was utilized to enhance the trajectory tracking ability of UAVs by reconciling the optimized reference path with real-time sensory inputs.Simulations and outdoor flight experiments demonstrated the effectiveness of the proposed framework.展开更多
As actively sensing animals guided by acoustic information, echolocating bats must adapt their vocal–motor behavior to various environmentsand behavioral tasks. Here, we investigated how the temporal patterns of echo...As actively sensing animals guided by acoustic information, echolocating bats must adapt their vocal–motor behavior to various environmentsand behavioral tasks. Here, we investigated how the temporal patterns of echolocation and flight behavior were adjusted in 2 species of batswith a high duty cycle (HDC) call structure, Rhinolophus ferrumequinum and Hipposideros armiger, when they flew along a straight corridorand then passed through windows of 3 different sizes. We also tested whether divergence existed in the adaptations of the 2 species. Both H.armiger and R. ferrumequinum increased their call rates by shortening the pulse duration and inter-pulse interval for more rapid spatial samplingof the environment when flying through smaller windows. Bats produced more sonar sound groups (SSGs) while maintaining a stable proportion of calls that made up SSGs during approaches to smaller windows. The 2 species showed divergent adjustment in flight behavior across3 different window sizes. Hipposideros armiger reduced its flight speed to pass through smaller windows while R. ferrumequinum increasedits flight speed. Our results suggest that these 2 species of HDC bats adopt similar acoustic timing patterns for different tasks although theyperformed different flight behaviors.展开更多
文摘Perception and manipulation tasks for robotic manipulators involving highly-cluttered objects have become increasingly indemand for achieving a more efficient problem solving method in modern industrial environments.But,most of the available methods for performing such cluttered tasks failed in terms of performance,mainly due to inability to adapt to the change of the environment and the handled objects.Here,we propose a new,near real-time approach to suction-based grasp point estimation in a highly cluttered environment by employing an affordance-based approach.Compared to the state-of-the-art,our proposed method offers two distinctive contributions.First,we use a modified deep neural network backbone for the input of the semantic segmentation,to classify pixel elements of the input red,green,blue and depth(RGBD)channel image which is then used to produce an affordance map,a pixel-wise probability map representing the probability of a successful grasping action in those particular pixel regions.Later,we incorporate a high speed semantic segmentation to the system,which makes our solution have a lower computational time.This approach does not need to have any prior knowledge or models of the objects since it removes the step of pose estimation and object recognition entirely compared to most of the current approaches and uses an assumption to grasp first then recognize later,which makes it possible to have an object-agnostic property.The system was designed to be used for household objects,but it can be easily extended to any kind of objects provided that the right dataset is used for training the models.Experimental results show the benefit of our approach which achieves a precision of 88.83%,compared to the 83.4%precision of the current state-of-the-art.
基金supported by the National Natural Science Foundation of China(No.62403025)the Basic Science Center Program of the National Natural Science Foundation of China(No.62388101)
文摘This paper proposed an autonomous planning,navigation and control framework for lightweight unmanned aerial vehicles(UAVs)in obstacle-dense environments with limited computational resources.The framework employed a polynomial-based minimum-snap trajectory generation method to ensure obstacle-free in confined three-dimensional(3D)spaces.A gradient-based trajectory optimization strategy integrated smoothness constraints,collision avoidance and dynamic feasibility was proposed to ensure safety and motion smoothness.The model predictive control(MPC)method was utilized to enhance the trajectory tracking ability of UAVs by reconciling the optimized reference path with real-time sensory inputs.Simulations and outdoor flight experiments demonstrated the effectiveness of the proposed framework.
基金supported by the National Natural Science Foundation of China(Grant No.31770429 and 32071492)the National Defense Basic Scientific Research Project of China(Grant No.C019220023).
文摘As actively sensing animals guided by acoustic information, echolocating bats must adapt their vocal–motor behavior to various environmentsand behavioral tasks. Here, we investigated how the temporal patterns of echolocation and flight behavior were adjusted in 2 species of batswith a high duty cycle (HDC) call structure, Rhinolophus ferrumequinum and Hipposideros armiger, when they flew along a straight corridorand then passed through windows of 3 different sizes. We also tested whether divergence existed in the adaptations of the 2 species. Both H.armiger and R. ferrumequinum increased their call rates by shortening the pulse duration and inter-pulse interval for more rapid spatial samplingof the environment when flying through smaller windows. Bats produced more sonar sound groups (SSGs) while maintaining a stable proportion of calls that made up SSGs during approaches to smaller windows. The 2 species showed divergent adjustment in flight behavior across3 different window sizes. Hipposideros armiger reduced its flight speed to pass through smaller windows while R. ferrumequinum increasedits flight speed. Our results suggest that these 2 species of HDC bats adopt similar acoustic timing patterns for different tasks although theyperformed different flight behaviors.
