Inspired by the movement of duck that is able to move on land and water utilizing its webbed feet, a novel design of an amphibious robot has been presented in this paper. In contrary, the orthodox design of amphibious...Inspired by the movement of duck that is able to move on land and water utilizing its webbed feet, a novel design of an amphibious robot has been presented in this paper. In contrary, the orthodox design of amphibious robot utilizes the tracks or wheels on land and switches to the propeller to move in water. The proposed design employs same propulsion system as webbed feet to move on land and water. After studying the movement of the duck underwater, a conclusion has been drawn that it is swimming in the water by moving its webbed feet back and forth to generate force to push its body forward. Recreating this phenomenon of duck movement, hybrid robot locomotion has been designed and developed which is able to walk, swim and climb steps using the same propulsion system. Moreover, webbed feet would be able to walk efficiently on muddy, icy or sandy terrain due to uneven distribution of robot weight on the feet. To be able to justify the feasibility of the design, simulations are being carried out using SimulationXpress of the SOLIDWORKS software.展开更多
While the recent release of the Chinese tree shrew （Tupaia belangeri chinensis） genome has made the tree shrew an increasingly viable experimental animal model for biomedical research, further study of the genome ma...While the recent release of the Chinese tree shrew （Tupaia belangeri chinensis） genome has made the tree shrew an increasingly viable experimental animal model for biomedical research, further study of the genome may facilitate new insights into the applicability of this model. For example, though the tree shrew has a rapid rate of speed and strong jumping ability, there are limited studies on its locomotion ability. In this study we used the available Chinese tree shrew genome information and compared the evolutionary pattern of 407 locomotion system related orthologs among five mammals （human, rhesus monkey, mouse, rat and dog） and the Chinese tree shrew. Our analyses identified 29 genes with significantly high co （Ka/Ks ratio） values and 48 amino acid sites in 14 genes showed significant evidence of positive selection in the Chinese tree shrew. Some of these positively selected genes, e.g. HOXA6 （homeobox A6） and AVP （arginine vasopressin）, play important roles in muscle contraction or skeletal morphogenesis. These results provide important clues in understanding the genetic bases of locomotor adaptation in the Chinese tree shrew.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 bro展开更多
A method of topology synthesis based on graph theory and mechanism combination theory was applied to the configuration design of locomotion systems of lunar exploration rovers(LER).Through topology combination of whee...A method of topology synthesis based on graph theory and mechanism combination theory was applied to the configuration design of locomotion systems of lunar exploration rovers(LER).Through topology combination of wheel structural unit,suspension unit,and connecting device unit between suspension and load platform,some new locomotion system configurations were proposed and the metrics and indexes to evaluate the performance of the new locomotion system were analyzed.Performance evaluation and comparison between two LER with locomotion systems of different configurations were analyzed.The analysis results indicate that the new locomotion system configuration has good trafficability performance.展开更多
A new kind of eight-wheel lunar rover is developed, which is a complex closed-chain system and has good capabilities of climbing slope, surmounting obstacles and adapting to uneven terrain. In this paper, the mechanic...A new kind of eight-wheel lunar rover is developed, which is a complex closed-chain system and has good capabilities of climbing slope, surmounting obstacles and adapting to uneven terrain. In this paper, the mechanical structure of the novel eight-wheel lunar rover is introduced, forward and inverse kinematic models of the rover are established according to the closed-chain coordinate transformation and instantaneous coincidence coordinate. Based on structural characteristics, its kinetic characteristics are analyzed. Wheel slippages are separated and calculated, and a method for closed-loop control modification using wheel slip estimation during the model establishment is proposed. The results can be applied to the motion control of lunar rover.展开更多
Motor function impairment is a common outcome of stroke.Constraint-induced movement therapy（CIMT）involving intensive use of the impaired limb while restraining the unaffected limb is widely used to overcome the effe...Motor function impairment is a common outcome of stroke.Constraint-induced movement therapy（CIMT）involving intensive use of the impaired limb while restraining the unaffected limb is widely used to overcome the effects of＇learned non-use＇and improve limb function after stroke.However,the underlying mechanism of CIMT remains unclear.In the present study,rats were randomly divided into a middle cerebral artery occlusion（model）group,a CIMT＋model（CIMT）group,or a sham group.Restriction of the affected limb by plaster cast was performed in the CIMT and sham groups.Compared with the model group,CIMT significantly improved the forelimb functional performance in rats.By western blot assay,the expression of phosphorylated extracellular regulated protein kinase in the bilateral cortex and hippocampi of cerebral ischemic rats in the CIMT group was significantly lower than that in the model group,and was similar to sham group levels.These data suggest that functional recovery after CIMT may be related to decreased expression of phosphorylated extracellular regulated protein kinase in the bilateral cortex and hippocampi.展开更多
Studying the locomotive behavior of animals has the potential to inspire the design of the mechanism and gait patterns of robots ("bio-inspired robots"). The kinematics characteristics of a spider (Ornithoct...Studying the locomotive behavior of animals has the potential to inspire the design of the mechanism and gait patterns of robots ("bio-inspired robots"). The kinematics characteristics of a spider (Ornithoctonus huwena), including movement of the legs, movement of the center of mass (COM) and joint-rotation angle, were obtained from the observation of locomotion behaviors recorded by a three-dimensional locomotion observation system. Our results showed that one set of the stance phase consists of four legs, which were leg-1 and leg-3 on one side and leg-2 and leg-4 on the other side. Additionally, two sets of the stance phase comprised eight legs alternately supporting and driving the motion of the spider's body. The spider primarily increased its movement velocity by increasing stride frequency. In comparison to other insects, the spider, O. huwena, has superior movement stability. The velocity and height of COM periodically fluctuated during movement, reaching a maximum during alternation of leg phase, and falling to a minimum in the steady stance phase. The small change in deflection angle of the hind-leg was effective in driving locomotion, whereas each joint-rotation angle of the fore-leg changed irregularly during locomotion. This research will help in the design of bio-inspired robots, including the selection of gait planning and its control.展开更多
This paper concerns with 3-D locomotion control methods for a biomimetic robot fish. The system architecture of the fish is firstly presented based on a physical model of carangiform fish. The robot fish has a flexibl...This paper concerns with 3-D locomotion control methods for a biomimetic robot fish. The system architecture of the fish is firstly presented based on a physical model of carangiform fish. The robot fish has a flexible body, a rigid caudal fin and a pair of pectoral fins, driven by several servomotors. The motion control of the robot fish are then divided into speed control, orientation control, submerge control and transient motion control, corresponding algorithms are detailed respectively. Finally, experiments and analyses on a 4-link, radio-controlled robot fish prototype with 3-D locomotion show its good performance.展开更多
文摘Inspired by the movement of duck that is able to move on land and water utilizing its webbed feet, a novel design of an amphibious robot has been presented in this paper. In contrary, the orthodox design of amphibious robot utilizes the tracks or wheels on land and switches to the propeller to move in water. The proposed design employs same propulsion system as webbed feet to move on land and water. After studying the movement of the duck underwater, a conclusion has been drawn that it is swimming in the water by moving its webbed feet back and forth to generate force to push its body forward. Recreating this phenomenon of duck movement, hybrid robot locomotion has been designed and developed which is able to walk, swim and climb steps using the same propulsion system. Moreover, webbed feet would be able to walk efficiently on muddy, icy or sandy terrain due to uneven distribution of robot weight on the feet. To be able to justify the feasibility of the design, simulations are being carried out using SimulationXpress of the SOLIDWORKS software.
基金Foundation items： This study was supported by the National 863 Project of China （2012AA021801, 2012AA022402） and grants from Chinese Academy of Sciences （KSCX2-EW-R-11, KSCX2-EW-J23） and Yunnan Province （2013FB071）Acknowledgements： We are grateful to Dr. Dong WANG for helpful discussion.
文摘While the recent release of the Chinese tree shrew （Tupaia belangeri chinensis） genome has made the tree shrew an increasingly viable experimental animal model for biomedical research, further study of the genome may facilitate new insights into the applicability of this model. For example, though the tree shrew has a rapid rate of speed and strong jumping ability, there are limited studies on its locomotion ability. In this study we used the available Chinese tree shrew genome information and compared the evolutionary pattern of 407 locomotion system related orthologs among five mammals （human, rhesus monkey, mouse, rat and dog） and the Chinese tree shrew. Our analyses identified 29 genes with significantly high co （Ka/Ks ratio） values and 48 amino acid sites in 14 genes showed significant evidence of positive selection in the Chinese tree shrew. Some of these positively selected genes, e.g. HOXA6 （homeobox A6） and AVP （arginine vasopressin）, play important roles in muscle contraction or skeletal morphogenesis. These results provide important clues in understanding the genetic bases of locomotor adaptation in the Chinese tree shrew.
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 bro
基金Supported by National "863" High-Tech Program (No.2006AA04Z231)Foundation of State Key Laboratory of Robotics and Systems (No.SKLRS-200801A02)+1 种基金the College Discipline Innovation Wisdom Plan (No.B07018)Natural Science Foundation of Heilongjiang Province (No.ZJG0709)
文摘A method of topology synthesis based on graph theory and mechanism combination theory was applied to the configuration design of locomotion systems of lunar exploration rovers(LER).Through topology combination of wheel structural unit,suspension unit,and connecting device unit between suspension and load platform,some new locomotion system configurations were proposed and the metrics and indexes to evaluate the performance of the new locomotion system were analyzed.Performance evaluation and comparison between two LER with locomotion systems of different configurations were analyzed.The analysis results indicate that the new locomotion system configuration has good trafficability performance.
基金Sponsored by the National Natural Science Foundation of China(Grant No.50975059)the National High-Tech Research and Development Program of China(863 Program)(Grant No.2006AA04Z231)+1 种基金the College Discipline Innovation Wisdom Plan(Grant No.B07018)Development Program of the Excellent Youth Scholars of Harbin Institute of Technology(Grant No.CACZ98504837)
文摘A new kind of eight-wheel lunar rover is developed, which is a complex closed-chain system and has good capabilities of climbing slope, surmounting obstacles and adapting to uneven terrain. In this paper, the mechanical structure of the novel eight-wheel lunar rover is introduced, forward and inverse kinematic models of the rover are established according to the closed-chain coordinate transformation and instantaneous coincidence coordinate. Based on structural characteristics, its kinetic characteristics are analyzed. Wheel slippages are separated and calculated, and a method for closed-loop control modification using wheel slip estimation during the model establishment is proposed. The results can be applied to the motion control of lunar rover.
基金supported by grants from the National Natural Science Foundation of China,No.81372119a grant from the Science and Technology Commission of Shanghai Municipality,No.12ZR1404000
文摘Motor function impairment is a common outcome of stroke.Constraint-induced movement therapy（CIMT）involving intensive use of the impaired limb while restraining the unaffected limb is widely used to overcome the effects of＇learned non-use＇and improve limb function after stroke.However,the underlying mechanism of CIMT remains unclear.In the present study,rats were randomly divided into a middle cerebral artery occlusion（model）group,a CIMT＋model（CIMT）group,or a sham group.Restriction of the affected limb by plaster cast was performed in the CIMT and sham groups.Compared with the model group,CIMT significantly improved the forelimb functional performance in rats.By western blot assay,the expression of phosphorylated extracellular regulated protein kinase in the bilateral cortex and hippocampi of cerebral ischemic rats in the CIMT group was significantly lower than that in the model group,and was similar to sham group levels.These data suggest that functional recovery after CIMT may be related to decreased expression of phosphorylated extracellular regulated protein kinase in the bilateral cortex and hippocampi.
基金supported by Funding for Outstanding Doctoral Dissertation in Nanjing University of Aeronautics and Astronautics (BCXJ10-10)the National Hi-Tech Research and Development Program of China (2007AA04Z201)the National Natural Science Foundation of China (60910007,31070344 and 50975140)
文摘Studying the locomotive behavior of animals has the potential to inspire the design of the mechanism and gait patterns of robots ("bio-inspired robots"). The kinematics characteristics of a spider (Ornithoctonus huwena), including movement of the legs, movement of the center of mass (COM) and joint-rotation angle, were obtained from the observation of locomotion behaviors recorded by a three-dimensional locomotion observation system. Our results showed that one set of the stance phase consists of four legs, which were leg-1 and leg-3 on one side and leg-2 and leg-4 on the other side. Additionally, two sets of the stance phase comprised eight legs alternately supporting and driving the motion of the spider's body. The spider primarily increased its movement velocity by increasing stride frequency. In comparison to other insects, the spider, O. huwena, has superior movement stability. The velocity and height of COM periodically fluctuated during movement, reaching a maximum during alternation of leg phase, and falling to a minimum in the steady stance phase. The small change in deflection angle of the hind-leg was effective in driving locomotion, whereas each joint-rotation angle of the fore-leg changed irregularly during locomotion. This research will help in the design of bio-inspired robots, including the selection of gait planning and its control.
基金This work was supported by National 973 Program (No. 2002CB312200) and National Hi-tech Development Project (No. 2003AA404190)
文摘This paper concerns with 3-D locomotion control methods for a biomimetic robot fish. The system architecture of the fish is firstly presented based on a physical model of carangiform fish. The robot fish has a flexible body, a rigid caudal fin and a pair of pectoral fins, driven by several servomotors. The motion control of the robot fish are then divided into speed control, orientation control, submerge control and transient motion control, corresponding algorithms are detailed respectively. Finally, experiments and analyses on a 4-link, radio-controlled robot fish prototype with 3-D locomotion show its good performance.
