Capturing Motion,
Crafting Stories

With the development of modern industry and the progress of science and technology, robot technology has penetrated into all fields of society, especially the robotic arm has become the backbone of industrial production. However, with the continuous improvement of people's requirements for production, people urgently hope that robots can do more complicated and delicate work like humans, but single-arm robots cannot meet such requirements. Therefore, it is urgent to carry out research on the related technologies of dual-arm robots.

Cui Ze, a teacher from School of Mechanical and Electrical Engineering and Automation, Shanghai University, used NOKOV optical 3D motion capture system to study the cooperative control of dual-arm robots. Workspaces overlap during independent movement, which may lead to accidental collision of dual-arm robots. Therefore, collision detection of dual-arm robot system is one of the important problems in trajectory planning of manipulator system.

Teacher Cui's team first pasted markers on the key nodes of the robot arm, and then used the capsule bounding box method to model the envelope of the dual-arm robot system according to the positions of these markers. Therefore, the collision detection of dual-arm robot can be transformed into interference inspection between spheres and cylinders, which greatly simplifies the difficulty of collision detection.

In addition, in the coordinated motion of dual-arm robots, the master-slave mode is usually adopted, that is, one is the master arm and the other is the slave arm. For two manipulators that can operate in coordination, it is necessary to find the coordination relationship between the joint position and speed of the master arm and the joint position and speed of the slave arm, which is specified by a set of complete equality constraints. 

NOKOV optical 3D motion capture system can not only give accurate sub-millimeter coordinates of markers, but also give data such as speed, acceleration and Euler angle of rigid body formed by corresponding points, so it can give real-time data for determining constraint relationship in the process of cooperative work.

For a long time, the market of industrial robot arm has been monopolized by some established enterprises in Europe and Japan. NOKOV measures motion capture to help the domestic industrial robot arm industry, and continuously empower the research and development of domestic robot arm and dual-arm robot system.