Design And Research Of Pneumatic Shaping Clamps

Grippers are widely used in automatic production lines to achieve the gripping manipulation for objects,making gripping and transformation operations more efficiently.However,most current grippers only perform the single task,and they are unable to complete multi-shape manipulation for objects with different shapes and material.Because of these problems,a new type of gripper is to be proposed with universality,flexibility and soft contact.Therefore,a new pneumatic soft gripper is proposed.It is integrated with the pneumatic soft-bending driving technology and the granular shaping technology.The new gripper is adaptive for a wide range of objects with different shapes,sizes and materials,and makes the gripping process flexible and reliable.Based on such scheme,the overall structure of the shaping gripper is studied and proposed.The methods to manufacture and assemble the soft components are explored.To understand the shaping mechanism,an in-depth analysis and research are made.The prototype of the shaping gripper is made and tested.Firstly,the overall structure of the shaping gripper is studied and designed,including the actuator base and the soft tentacle modular.The soft tentacle modular consists of soft arms and shaping units.The functions and actions of the drive base,the soft tentacle modular and the whole gripper are analyzed respectively.The methods of fabricating the shaping gripper are explored and proposed,especially for soft tentacle modular.For the typical problems such as difficulties in manufacturing and assembling soft components,low fabrication rate,etc,methods are carried out to solve these problems,including separate mold,layer by layer casting,subdividing mold and adding orientation features,and so on.On basis of the shaping mechanisms of the shaping gripper,the mechanism of the flexible arm and passive shaping mechanism of the membrane contact surface are deeply analyzed and studied.A flexible arm structure with inflatable bending function is proposed.Finite element analysis and experiments are carried out to validate the feasibility.It is found that the flexible arm realizes a wide range of bending operations,and the experimental results agree well with simulation result for the same deformation trend.The experimental result on passive shaping mechanism of the contact surface is also obtained,including designing and building experimental platform for the granular shaping experiment,through which the parameters like vacuum degree and the granular materials are experimentally studied.The experimental results show that when the vacuum degree is higher than 65kPa,the the membrane acquires better constraint ability and it is easy to be stable.The granular materials with higher hardness will obtain stronger constraint ability.To test the performance of the shaping gripper,a prototype gripper and gripping system is fabricated and built up to handle objects.It is found that the shaping gripper can handle objects with different shapes,such as spherical,cylindrical,rectangular,etc.,and has good adaptability to different sizes of objects whose dimension range from 15mm to 125mm.Due to the soft contact surface of the shaping gripper,objects with different materials,like metals,plastics can be easily handled.Food products like fruits and vegetables,are also manipulated conveniently by the new gripper.By using the new kind of gripper,objects in the flowing manufacturing lines could be easily picked up and transported.It is also useful for marine exploration and food industries.