Motion generation for pulling a fire hose by a humanoid robot

This paper discusses a strategy for a humanoid robot to pull a fire hose while walking towards a desired position and orientation. A hybrid controller on the robot's wrist holding the fire hose is implemented for pulling it. The proposed controller can automatically determine the pulling force according to the robot's walking velocity. Through simulation analysis it is shown that when the robot walks while pulling the fire hose a drift in the walking direction is generated. To cope with this drift and to direct the robot to a desired position and orientation, a walking task is introduced. Using a motion capture system, the robot's chest position and orientation are monitored and feed to the robot's walking pattern generator to correct the orientation drift and to determine where to walk and when to stop walking. Through experimental results the validity of the proposed strategy was confirmed. It is shown that the proposed hybrid controller contributes to the improvement of the robot's balance when walking.