Design And Analysis Of Flexible Capture Mechanism Inspired By Sea Anemone For Non-cooperative Targets

With the rapid development of the economy and the continuous advancement of science and technology,human beings are broadening their research and exploration to unknown environments such as space and underwater.The capture of non-cooperative targets is also an important challenge in the robot field.It is necessary to ensure that the capture mechanism can grasp the target and avoid the capture mechanism from causing a large collision impact when contacting the target,thereby causing damage to the target and itself.In order to meet the non-cooperative target capture tasks in space,underwater and other environments,a novel capture mechanism using continuum-arm swarm inspired by the anatomy and motions of sea anemones considering the manipulation characteristics of high tolerance,high adaptability and rigid-flexible coupling is proposed.The dynamic target entering the arm swarm from any direction is captured by the "contact-wrap-lock" procedure.The content is as follows:In this paper,a novel capture mechanism using continuum-arm swarm was designed by studying the structure and capture mode of sea anemone and integrating the requirements of space non-cooperative target capture mission.A plurality of variable stiffness continuum single arms are used as the basic unit,and a plurality of rotating joints and ball joints are connected in series to form a central skeleton of the continuous arms,and a variable stiffness mechanism is designed based on the frictional adjustment.The underdrive control of single-input multi-degree-of-freedom motion is realized by a wire-drive mechanism.Based on the target size to be captured,the structural parameters of the capture mechanism are selected and a three-dimensional model of the capture mechanism is established.Based on the assumptions of the kinematics analysis hypothesis,a kinematic model of a single underactuated continuum manipulator is established.Under the passive driving of the target,the working space of the continuous single arm end point was simulated by Matlab software.Considering the influence of gravity and friction factors,the finite element model of the capture mechanism using continuum-arm swarm inspired by is established by using the integrated working environment analysis of ABAQUS/CAE.The finite element simulation is used to simulate the continuum-arm swarm and dynamic target contact until the target is captured.The process and the energy curve and the velocity curve of the target are analyzed.The three distribution patterns of the arm group are the research objects,and the effects on the capture performance when the targets with different diameters are in contact with the continuum-arm swarm at different speeds.Set up an experimental platform for the capture mechanism to perform related performance tests,including grabbing experiments on static irregular targets and capturing experiments on dynamic targets.Based on the physical prototype construction,the feasibility of continuum-arm swarm capture was verified by experiments.