Manipulator system for the redevelopment of gaps in bricks sewers

At present only small sewers shap can automatically be renewed. Large brick sewers which are often found in nearly every large city still have to be repaired manually. Therefore, the company HOCHTIEF and the Fraunhofer-Gesellschaft have developed a remote-controlled manipulator system. This machine is a hydraulic powered robot with 5 degrees of freedom that automatically cuts out the mortar and refills the grooves. Two CCD-cameras are integrated in the wrist axes, directed at the tool, while a third camera is mounted on the vehicle and gives the operator an overview of the working area. The operator defines, via the TV-image, the edges of the brick sewers that have to be renewed. This operation is mostly computer-aided. The task of the operator is reduced to the monitoring the robot's movement and the correcting the computed robot path with a joystick. Initially the joints are cut by a finger milling cutter, then mortar is pressed into the groove and smoothed. The robot can be dismantl ed and therefore can be transported through manholes with a diameter of 625 mm. The current version was designed for oval sewers with a height of 1400 mm and a width of 850 mm. The robot is mounted on a walking gear to move through the sewer. In a container outside the sewer, control instruments and monitors inform the operator about the state of the machine and the state of the work process.