Puma-robot evaluation for laser manufacturing applications

Combinations of the flexibility of industrial robots and the many advantages of laser technology are becoming increasingly common. An industrial robot can manipulate an object under a laser beam during, for example, welding, cutting or heat treatment. Properties of a Puma robot were investigated with a view to its possible incorporation into a laser-robot system. The following properties were measured; robot arm flexibility, inaccuracy of the robot and the gripper, vibrations during movement, overshoot in linear interpolation movement, repeatability etc. The flexibility of the robot arm was 0.5...0.7 mm when a load of 2 kg was attached to the gripper. The overshoot was slight at small velocities and 0.45...0.65 mm at the velocity of 200 mm/s, when the gripper was driven into a point in different directions. The repeatability of the robot was usually +/-0.07...0.11 mm. The maximum value was +/-0.14 mm. Vibrations during gripper movement cause more difficulties in laser manufacturing than errors in repeatability. The laser-robot system can be used in industrial applications where high precision is not necessary. The application area of the robot-laser system increases, when more accurate robots are developed.