There are many kinds of swimming mode in the fish world, and we investigated two of them, used by cyprinids and bulltrout. In this paper we track the locomotion locus by marks in different flow velocity from 0.2 m...There are many kinds of swimming mode in the fish world, and we investigated two of them, used by cyprinids and bulltrout. In this paper we track the locomotion locus by marks in different flow velocity from 0.2 m·s^-1 to 0.8 m·s^-1. By fit the data above we could find out the locomotion mechanism of the two kinds of fish and generate a mathematical model of fish kine- matics. The cyprinid fish has a greater oscillation period and amplitude compared with the bulltrout, and the bulltrout changes velocity mainly by controlling frequency of oscillation.展开更多
Locomotion performance degradation after carrying payloads is a significant challenge for insect-scale microrobots.Previously,a legged microrobot named BHMbot with a high load-carrying capacity based on front-leg actu...Locomotion performance degradation after carrying payloads is a significant challenge for insect-scale microrobots.Previously,a legged microrobot named BHMbot with a high load-carrying capacity based on front-leg actuation configuration and efficient running gait was proposed.However,insects,mammals and reptiles in nature typically use their powerful rear legs to achieve rapid running gaits for predation or risk evasion.In this work,the load-carrying capacity of the BHMbots with front-leg actuation and rear-leg actuation configurations is comparatively studied.Simulations based on a dynamic model with four degrees of freedom,along with experiments,have been conducted to analyze the locomotion characteristics of the two configurations under different payload masses.Both simulation and experimental results indicate that the load-carrying capacity of the microrobots is closely related to their actuation configurations,which leads to different dynamic responses of the microrobots after carrying varying payload masses.For microrobots with body lengths of 15 mm,the rear-leg actuation configuration exhibits a 31.2%enhancement in running speed compared to the front-leg actuation configuration when unloaded.Conversely,when carrying payloads exceeding 5.7 times the body mass(350 mg),the rear-leg actuation configuration demonstrates an 80.1%reduction in running speed relative to the front-leg actuation configuration under the same payload conditions.展开更多
With slim and legless body, particular ball articulation, and rhythmic locomotion, a nature snake adapted itself to many terrains under the control of a neuron system. Based on analyzing the locomotion mechanism, the ...With slim and legless body, particular ball articulation, and rhythmic locomotion, a nature snake adapted itself to many terrains under the control of a neuron system. Based on analyzing the locomotion mechanism, the main functional features of the motor system in snakes are specified in detail. Furthermore, a bidirectional cyclic inhibitory （BCl） CPG model is applied for the first time to imitate the pattern generation for the locomotion control of the snake-like robot, and its characteristics are discussed, particularly for the generation of three kinds of rhythmic locomotion. Moreover, we introduce the neuron network organized by the BCI-CPGs connected in line with unilateral excitation to switch automatically locomotion pattern of a snake-like robot under different commands from the higher level control neuron and present a necessary condition for the CPG neuron network to sustain a rhythmic output. The validity for the generation of different kinds of rhythmic locomotion modes by the CPG network are verified by the dynamic simulations and experiments. This research provided a new method to model the generation mechanism of the rhythmic pattern of the snake.展开更多
基金the National Natural Science Foundation of China (Grant No. 50579007)
文摘There are many kinds of swimming mode in the fish world, and we investigated two of them, used by cyprinids and bulltrout. In this paper we track the locomotion locus by marks in different flow velocity from 0.2 m·s^-1 to 0.8 m·s^-1. By fit the data above we could find out the locomotion mechanism of the two kinds of fish and generate a mathematical model of fish kine- matics. The cyprinid fish has a greater oscillation period and amplitude compared with the bulltrout, and the bulltrout changes velocity mainly by controlling frequency of oscillation.
基金supported in part by Beijing Natural Science Foundation under Grant 3232010in part by the National Natural Science Foundation of China under Grant 12002017+2 种基金in part by AECC Industry-university Collocation Fund under Grant HFZL2023CXY026in part by Beihang Outstanding Young Scholars Project under Grant YWF-23-L-1201in part by 111 Project under Grant B08009.
文摘Locomotion performance degradation after carrying payloads is a significant challenge for insect-scale microrobots.Previously,a legged microrobot named BHMbot with a high load-carrying capacity based on front-leg actuation configuration and efficient running gait was proposed.However,insects,mammals and reptiles in nature typically use their powerful rear legs to achieve rapid running gaits for predation or risk evasion.In this work,the load-carrying capacity of the BHMbots with front-leg actuation and rear-leg actuation configurations is comparatively studied.Simulations based on a dynamic model with four degrees of freedom,along with experiments,have been conducted to analyze the locomotion characteristics of the two configurations under different payload masses.Both simulation and experimental results indicate that the load-carrying capacity of the microrobots is closely related to their actuation configurations,which leads to different dynamic responses of the microrobots after carrying varying payload masses.For microrobots with body lengths of 15 mm,the rear-leg actuation configuration exhibits a 31.2%enhancement in running speed compared to the front-leg actuation configuration when unloaded.Conversely,when carrying payloads exceeding 5.7 times the body mass(350 mg),the rear-leg actuation configuration demonstrates an 80.1%reduction in running speed relative to the front-leg actuation configuration under the same payload conditions.
基金Supported in part by the National Natural Science Foundation of China (Grant No. 60375029)the National Hi-tech Research and Development Plan (Grant No. 2001AA422360)the Japan Society for the Promotion of Science Grants-in-Aid (Grant No. 15360129)
文摘With slim and legless body, particular ball articulation, and rhythmic locomotion, a nature snake adapted itself to many terrains under the control of a neuron system. Based on analyzing the locomotion mechanism, the main functional features of the motor system in snakes are specified in detail. Furthermore, a bidirectional cyclic inhibitory （BCl） CPG model is applied for the first time to imitate the pattern generation for the locomotion control of the snake-like robot, and its characteristics are discussed, particularly for the generation of three kinds of rhythmic locomotion. Moreover, we introduce the neuron network organized by the BCI-CPGs connected in line with unilateral excitation to switch automatically locomotion pattern of a snake-like robot under different commands from the higher level control neuron and present a necessary condition for the CPG neuron network to sustain a rhythmic output. The validity for the generation of different kinds of rhythmic locomotion modes by the CPG network are verified by the dynamic simulations and experiments. This research provided a new method to model the generation mechanism of the rhythmic pattern of the snake.
