Research On Struction Design And Control Of Full Drive Dexterous Hand

With the continuous development of The times and the explosive demand of robot service industry and industrial robot field,domestic and foreign scholars have conducted a lot of in-depth research on robot technology from all sides,and a variety of mechanical dexterous hands have emerged.an be roughly divided into full dexterous hand drive mode can drive the dexterous hand with underactuated dexterous hand,drive all forms of dexterous hand freedom,space configuration can be more complex,so it can accomplish complex and delicate crawl,full drive humanoid dexterous hand and manpower to similar institutions and exercise flexibility,can replace human in a complex and dangerous environment to complete all kinds of complex operations.According to the driver of dexterous hand,dexterous hand can be divided into three types: pneumatic/hydraulic drive mode,micro reduction motor drive and new drive material.Although the pneumatic drive can achieve high flexibility and fast response speed,its control system is cumbersome,large in size and poor in convenience.The smart hand driven by shape memory alloy has the advantages of small size and quick response,but it has high power consumption,long working cycle and is not suitable for frequent grasping.Due to micro size small,big reduction ratio,flexible drive arrangement,this paper combined with shape memory alloy and miniature motor compound drive way,we design a two-stage deceleration based on micro motor drive mode of the new drive five fingers dexterous hand,and studied the dexterous hand grasping control strategy,mainly completed the following contents:On the basis of reading many domestic and foreign literatures on dexterous hand in detail,the structural design and transmission characteristics of dexterous hand in different driving modes are analyzed and studied,and the structural design parameters of dexterous hand in this paper are given according to the 1:1 ratio between the size of human hand and the kinematic characteristics of human hand.Dexterous hand with five fingers,each finger has three degrees of freedom,and a lateral buckling degree of freedom and the dexterous hand with 20 separate freedom of motion control,through the double deck arrangement will be put in the palm of your hand miniature two-stage deceleration motor,and USES the SMA spring as side swing drive,through the motor output plate of the variable diameter design of both the large initial start-up force and fast response requirements,make the dexterous hand structure more compact.Based on the structural parameters of the dexterous hand,the kinematics model of the dexterous hand prototype was established according to the d-h parameter analysis method,the forward and inverse kinematics of the dexterous hand was analyzed,and the workspace of the dexterous hand was simulated by Matlab.Completed the construction of the overall hardware control system of dexterous hand.Arduino was used as the control chip of dexterous hand,which mainly included the drive subsystem,the control subsystem and the sensor feedback subsystem.The pressure sensor was calibrated,and the fingertip pressure PID control system was built to realize stable grasping force control.Based on the feedback of SV103 Angle sensor,the precise grasping of dexterous hand was studied,and a hybrid force/position control strategy was proposed.The trajectory planning algorithm was used to control the joint Angle,velocity and acceleration of dexterous hand in real time,so as to realize the rapid and stable grasping operation of dexterous hand.Driven by 3D printing completed the full dexterous hand physical prototype preparation and assembly,and through a portable control system,to the life of common items fetching experiment was carried out,the results showed that: in this paper,the design of the whole drive dexterous hand with simple assembly,low cost,flexible movement,grasping performance characteristics,and through the force/position hybrid control method to achieve the soft shock,crawl grab mode,can be in different application scenarios to achieve safe,effective and stable grasping operation,has a certain application value.