Ningbo Materials made four degrees of freedom parallel robot made progress

Parallel robots have the advantages of high rigidity, high speed, high flexibility and light weight, and they form an important part of industrial robots together with tandem robots. In recent years, with the unparalleled advantages of parallel robots in light industry such as foodstuff, medicine and electronics as well as unparalleled advantages in material handling, packaging and sorting, the parallel robot has become a new force in the growth of industrial robot demand.

Institute of Advanced Manufacturing Technology, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences Precision motion and advanced robotic team The newly designed 4-DOF parallel robot can achieve 3T1R four-degree-of-freedom motion and is one of the innovative designs of a few degrees of freedom parallel robot The main feature is that two identical branches are connected to the moving platform through passive turning pairs, and two identical branches of each branch are driven by a moving pair mounted on the base. In order to further analyze the characteristics of the mechanism, the number of degrees of freedom of the mechanism and the kinematic characteristics of the mechanism are verified by the spiral theory. The closed solutions of the mechanism are obtained. According to the kinematics and configuration features of the mechanism, There are at most 8 groups of solutions, with up to 4 groups of solutions in inverse position. The results show that kinematic analysis is simple and is one of the characteristics of this parallel robot. In addition, with a symmetrical configuration, large working space, high speed and high positioning accuracy. Compared with the traditional parallel robot, it can realize XYZ three-direction movement and one rotation around the Z-axis, and the working space in the driving direction can be expanded according to the operation requirement, increasing the working space range.

The parallel robot prototype uses a high precision linear motor with a stator and two mover as its driving mechanism for each branch of the parallel robot prototype. The structure is simple and the motor positioning accuracy reaches the micron level. In addition, the high-strength carbon fiber composite material is used as the main material of the branch chain , Effectively reducing the weight of the moving parts; control system uses ABB's drive, through the PowerLink bus synchronization control; through kinematics-based offline trajectory planning algorithm, the body's kinematics at present the prototype can be achieved in three directions XYZ flat Movement and Z-axis direction of rotation, the movement range is 0.3m, 1.2m and 0.2m, the maximum movement speed reached 1.6m / s, the end of the positioning accuracy of about 1mm, around the Z-axis rotation can reach ± ​​120 °, can be widely used in flexible chemical plant packaging, sorting and other processes, with good application prospects.

Four degrees of freedom parallel mechanism structure

Parallel robot diagram

Parallel robot work space