Capturing Motion,
Crafting Stories

With the rapid development of science and technology, China has put forward the "Made in China 2025" plan to revitalize the manufacturing industry. The key development direction is intelligence and improving resource utilization. The application of all kinds of robots is an important embodiment of the intelligentization of manufacturing industry. With the support of policies, the application fields and quantity will increase greatly, which requires that the reliability and applicability of robots must meet the basic requirements of the development of the industry.

However, in the process of robot development, due to the sensor accuracy, the advantages and disadvantages of the control system and so on, it is inevitable that the robot will have deviations when performing tasks, such as the pose deviation of the end effector of the robotic arm, the movement trajectory deviation of the mobile robot and so on. At this time, it is necessary to acquire robot information by precise measuring means, and then carry out calibration or detection and evaluation.

Industrial robots have high repeatability and positioning accuracy, so they need to use laser tracker and other measuring equipment with micron-scale measurement accuracy for detection and calibration. However, in some scenarios, such as measuring the motion trajectory of mobile robots, the accuracy of sub-millimeter or even millimeter can meet the requirements, so there is no need to use millions of laser tracker equipment. Zhejiang Pumai Technology Co., Ltd. has developed a robot performance test system based on motion capture system.

Spectrum Mai Technology itself focuses on the research and application of industrial robot performance measurement and calibration technology. The system is mainly based on laser tracker and other equipment, and supports the performance measurement of robot pose accuracy and repeatability, position stabilization time, trajectory accuracy and so on. In order to refine the product line and cover more testing requirements, Spectrum Mai Technology developed a robot performance testing system based on NOKOV optical motion capture system. The measurement accuracy requirements of customers are met, and the test cost is greatly reduced.

The positioning principle of NOKOV optical 3D motion capture system is different from that of laser tracker. The system locates the key nodes of the robot by capturing markers with multiple motion capture cameras, and calculates the robot pose according to the coordinates of the markers, with sub-millimeter positioning accuracy.

Zhejiang Premax Technologies engineers set up a 4m*4m experimental site, with eight NOKOV measurement motion capture cameras distributed around the site, and obstacles in the middle of the site to simulate the actual scene. The sweeping robot can avoid collision based on its own sensors. The robot body is pasted with markers, and the actual position is obtained as the true value, which is compared with the estimated position of the robot itself to evaluate the performance (accuracy, response speed, etc.) of the sweeping robot. The measured accuracy of the system meets the requirements of similar applications.