Spatial Control of High Speed Robot Arms using a Tilted Camera

The paper demonstrates that when mounted on a robot endeector a camera can be used to control the robot arm to move at high speed along a given workpiece. We use a predictive architecture that considers both the robot’s dynamics and the workpiece’s uncertainties of the pose or shape. To comply with applications such as glue spraying or laser cutting, the camera is mounted laterally with respect to the tool and, for reasons of visibility, tilted. This complicates the control equations. Nevertheless we manage to compute them in real time and to follow a non planar tube at a speed of 0.7 m/s. In spite of a cost eective hardware setup the mean path deviations are less than 1 mm.

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