Different from sculling forward of water striders with their hairy water-repellent legs, water spiders walked very quickly on water surfaces. By using a shadow method, the walking of water spiders had been studied. Th...Different from sculling forward of water striders with their hairy water-repellent legs, water spiders walked very quickly on water surfaces. By using a shadow method, the walking of water spiders had been studied. The three-dimensional trajectories and the supporting forces of water spider legs during walking forward were achieved. Results showed that the leg movement could be divided into three phases： slap, stroke, and retrieve. Employing an effective strategy to improving walking efficiency, the sculling legs supported most of its body weight while other legs were lifted to reduce the lateral water resistance, which was similar to the strategy of water striders. These findings could help guiding the design of water walking robots with high efficiency.展开更多
Measuring walking forces of small or tiny insects can help the comprehension of their locomotion principles.However,as their size and force are generally too small,walking forces of small insects in sub-mg mass have n...Measuring walking forces of small or tiny insects can help the comprehension of their locomotion principles.However,as their size and force are generally too small,walking forces of small insects in sub-mg mass have never been actually measured.In this work,a convenient multi-lens and jelly surface based shadow method was developed for simultaneous multiple walking forces measuring,ranged from nN to mN with a sensitivity of sub-nN/pixel under ambient conditions.Walking force of six legs of a 0.3 mg water treader was demonstrated.The obtained results disclosed a rapid and extending middle leg strategy of water treader in walking forward above a jelly surface.This method is cost-effective and high-resolution,which could be easily used in measuring other tiny forces.展开更多
The concept of legged-robot stability training with a training platform is proposed and a serial-parallel mechanism platform with 6 degrees of freedom is designed for this target. The designed platform is composed of ...The concept of legged-robot stability training with a training platform is proposed and a serial-parallel mechanism platform with 6 degrees of freedom is designed for this target. The designed platform is composed of 4-DOF parallel mechanism with spherical joints and prismatic pairs,and 2-DOF serial mechanism with prismatic pairs. With this design,the platform has advantages of low platform countertop,big workspace,high carrying capacity and high stiffness. On the basis of DOF analysis and computation of space mechanism,weight supporting auxiliary mechanism and raceways-balls supporting mechanism are designed,so as to improve the stiffness of designed large platform and payload capacity of servo motors. And then the whole structure design work of the platform is done. Meanwhile,this paper derives the analytical solutions of forward kinematics, inverse kinematics and inverse dynamics. The error analysis model of position and orientation is established. And then the simulation is done in ADAMS to ensure the correctness and feasibility of this design.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.51323006 and 51425502)the Tribology Science Fund of State Key Laboratory of Tribology(Grant No.SKLTKF17B18)
文摘Different from sculling forward of water striders with their hairy water-repellent legs, water spiders walked very quickly on water surfaces. By using a shadow method, the walking of water spiders had been studied. The three-dimensional trajectories and the supporting forces of water spider legs during walking forward were achieved. Results showed that the leg movement could be divided into three phases： slap, stroke, and retrieve. Employing an effective strategy to improving walking efficiency, the sculling legs supported most of its body weight while other legs were lifted to reduce the lateral water resistance, which was similar to the strategy of water striders. These findings could help guiding the design of water walking robots with high efficiency.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.51323006 and 51425502)。
文摘Measuring walking forces of small or tiny insects can help the comprehension of their locomotion principles.However,as their size and force are generally too small,walking forces of small insects in sub-mg mass have never been actually measured.In this work,a convenient multi-lens and jelly surface based shadow method was developed for simultaneous multiple walking forces measuring,ranged from nN to mN with a sensitivity of sub-nN/pixel under ambient conditions.Walking force of six legs of a 0.3 mg water treader was demonstrated.The obtained results disclosed a rapid and extending middle leg strategy of water treader in walking forward above a jelly surface.This method is cost-effective and high-resolution,which could be easily used in measuring other tiny forces.
基金Sponsored by the National High-Tech Research and Development Program(Grant No.2006AA04Z201)
文摘The concept of legged-robot stability training with a training platform is proposed and a serial-parallel mechanism platform with 6 degrees of freedom is designed for this target. The designed platform is composed of 4-DOF parallel mechanism with spherical joints and prismatic pairs,and 2-DOF serial mechanism with prismatic pairs. With this design,the platform has advantages of low platform countertop,big workspace,high carrying capacity and high stiffness. On the basis of DOF analysis and computation of space mechanism,weight supporting auxiliary mechanism and raceways-balls supporting mechanism are designed,so as to improve the stiffness of designed large platform and payload capacity of servo motors. And then the whole structure design work of the platform is done. Meanwhile,this paper derives the analytical solutions of forward kinematics, inverse kinematics and inverse dynamics. The error analysis model of position and orientation is established. And then the simulation is done in ADAMS to ensure the correctness and feasibility of this design.
