The-lightweight-building-robot-LBR-iiwa-supports-employees-in-bonding-processes

Lightweight robots support operators in adhesive bonding processes

Dürr uses two sensitive LBR iiwa robots from KUKA in final assembly. Without a safety fence, they perform key tasks in the application of adhesive beads. This improves quality, saves time and lowers unit costs.

At Dürr, humans and robots work together in final assembly without the need for physical safeguards. Sensitive LBR iiwa lightweight robots from KUKA are used for the adhesive bonding of GPS antenna covers and tanks in the vehicle body. The solutions improve the quality of the adhesive bonding result, save time and lower unit costs.

The LBR iiwa detects any fault that arises when the GPS antenna cover is loaded

For application of adhesive to the GPS antenna cover, the assembly worker places the workpiece into the robot gripper manually. The gripper sucks onto it and moves it to the adhesive nozzle on the application tower. The LBR iiwa slowly moves the GPS antenna cover upwards to the application nozzle. If it encounters an obstacle, it moves back a little thanks to its collision detection ability and starts the motion over from the beginning. Only after three attempts does it move back into the starting position. Otherwise, the adhesive application process starts and the adhesive bead is applied carefully while the robot executes the path. Finally, back at the starting point, the assembly worker removes the GPS antenna cover and mounts it on the vehicle.

The gripper of the LBR iiwa holds the workpiece by suction and moves it to the adhesive nozzle on the application tower.

Precise adhesive beads thanks to the seventh axis of the LBR iiwa

For the automated process of gluing the tank into place in final assembly, the skilled worker guides the tank to a turntable with the aid of a manipulator. There he cleans it, moves it into the correct position and transfers it directly to the robot for further processing. When the starting point is reached on the stationary tank, the nozzle opens under pressure so that no air bubbles are created. The robot then applies the adhesive bead onto the tank very evenly. Sensors on the application head monitor the accurate height of the bead. Thanks to its seventh rotating axis, the LBR iiwa glues in a radius of 360 degrees – without re-orienting or having to interrupt the bead. As soon as the LBR iiwa has completed its task, the skilled worker fits the tank into the vehicle body at the specified position.

It is definitely possible to apply an adhesive bead by hand, but the result cannot match the precision of a robot.

Dieter Ahlborn, Director APT/Gluing Final Assembly, Dürr Systems AG

HRC solutions as a market of the future

Dürr has already sold ten systems in the field of adhesive bonding. System and machine builder Dürr thus has an optimistic outlook for the future. The company is already working on HRC solutions for the robot-based adhesive bonding of small washers and other components.