Toward Intelligent Robotics for High Accuracy Aerospace Applications 2013-01-2293

Industrial robot manipulators are widely used for different automated applications where flexibility is necessary or where repetitive tasks are present. These systems are designed for optimum repeatability and little emphasis is given to the accuracy aspect.

In recent years, we see an increase of interest in the aerospace industry for using industrial robots in applications where more precision is necessary. For this purpose, many solutions were proposed in the last years for dynamically tracking the robot TCP (tool center point). These systems are very interesting when the workspace and the robot cell are large enough to accommodate the minimum stand-off of the tracking system.

In this work, we present two alternatives for increasing the accuracy of industrial robots. The first approach uses vision-based servoing of the TCP in order to accomplish specific tasks in small workspaces. One and two cameras scenarios are presented. The second approach uses machine vision for robot geometric calibration. A camera mounted on a robot captures different images of the scene at different robot poses and computes the joint errors. A new kinematic model is then obtained and used in order to increase the robot accuracy. These two approaches can be combined for better convergence. The obtained results are very promising and show the possibility of achieving high accuracy using vision-based techniques with industrial robots. Also, the proposed solutions can work in smaller areas and achieve higher accuracy than traditional tracking systems.