Font Size: a A A

Kinematics Study And Trajectory Planning Of A Two-armed Parallel Robot

Posted on:2024-06-19Degree:MasterType:Thesis
Country:ChinaCandidate:H WangFull Text:PDF
GTID:2568307115492824Subject:Information and Communication Engineering
Abstract/Summary:PDF Full Text Request
The two-armed parallel robot has received a lot of attention from scholars and companies because of its high accuracy,high speed,easy control and low development cost.In this paper,this robot is studied in the following aspects: implementation of end positioning,analysis of workspace,prediction of singularity shape,analysis of kinematic performance,and end trajectory planning.Among them,the first four tasks are kinematic research,kinematic research is the basis of control of parallel robots,and end trajectory planning is built on the basis of kinematics to optimize the trajectory in order to achieve smooth vibration reduction and improve efficiency.The specific research is as follows:Firstly,this paper establishes the mathematical model of the robot by introducing the structure and degrees of freedom of the two-armed parallel robot,lists the system of kinematic equations using geometric relations and solves its positive and negative solutions,that is,the end positioning of the robot is realized.Combined with the mechanical parameters of the experimental robot,the numerical verification of the forward and inverse solutions is completed,and the reachable and effective workspaces of the two-armed parallel robot are analyzed on the basis of the positive solutions,which paves the way for the end trajectory planning.Secondly,when the robot is in singular dislocation,it will make the robot suddenly lose control during the working process;therefore,the prediction of singular dislocation is a necessary part of robot research.In this paper,we propose a singular dislocation prediction method for a two-armed parallel robot,which is implemented based on the Jacobi matrix determinant.In the paper,all the singular dislocations present in the two-armed parallel robot are predicted by this prediction method and the predicted dislocations are verified on a physical platform,and the results show that the prediction scheme proposed in this paper is feasible.The kinematic performance is further investigated in the paper,where the kinematic performance is measured using the maneuverability and dexterity metrics.By calculating the distribution of the above metrics in the effective working space,it is demonstrated that there is no bit shape close to the singular bit shape in this space.Finally,in order to ensure that the end velocity,acceleration,and jerk curves of the robot arm are smooth and continuous during production operations,and to avoid violent vibration of the robot arm during high-speed operation.The paper researches the robot end trajectory planning,and proposes a segmented velocity curve trajectory planning method based on the analysis of the traditional end trajectory planning algorithm,which greatly simplifies the determination of boundary conditions and computation compared with the traditional spline algorithm,and can realize the velocity,acceleration and jerk curve of the end trajectory of the robot arm only given the running trajectory points and the desired running time The velocity,acceleration,and jerk curve fluctuation amplitude and overall motion period can be controlled individually by adjusting the factor and segmentation time interval.In the robot platform provided by the laboratory,the comparison experiments between the algorithm of this paper and the traditional algorithm and the comparison experiments of the algorithm of this paper with different values of the adjustment factor are carried out in turn,and the results show that the algorithm proposed in this paper can not only play the effect of smooth damping,but also realize the adjustment of the smoothness of the trajectory and the fluctuation amplitude of the motion characteristic curve by changing the adjustment factor in the algorithm.
Keywords/Search Tags:Two-arm parallel robot, forward-inverse solution, singular dislocation, kinematic performance, end trajectory planning
PDF Full Text Request
Related items