Determining ball trajectory on a work plate held by a dual-arm SCARA robot using IMU sensor data

In recent years, new industrial robots have been applied to a wider range of production sites, and measurement and evaluation techniques have become indispensable for improving their motion accuracy. In a previous study, the trajectory of a ball on a plate grasped by a robot was found to be an indicator of the robot's motion accuracy. This study focused on the ball itself on a plate and conducted experiments to synchronize reality and simulation in a digital twin. A 3D printed ball, equipped with a wireless inertial measurement unit (IMU), was moved onto a plate grasped by a dual-arm robot. The trajectory of the ball was calculated and compared with the results obtained from camera measurements. Thus, the validity of these calculations was demonstrated. The results indicate that by using a quaternion to calculate the amount of microrotation, the motion of the ball due to the horizontal plane manipulation of the plate can be calculated without the influence of the singularity of the rotation matrix.