A method for managing a robot arm , comprising: receiving , during a movement of the robot arm in an axis of the robot arm , a signal collected by a sensor equipped at a frame of the robot arm ; detecting a change in strength of the received signal , the change being caused by an offset between a position of a reference mark equipped at the robot arm and a position of the sensor ; and determining an original point of the axis of the robot arm based on the detected change, wherein detecting the change in the strength of the signal comprises: detecting any of a center and an extremity of a fluctuation in the strength of the signal, wherein determining the original point of the axis further comprises: determining a position of the robot arm in the axis based on any of the center and the extremity of the fluctuation, the strength of the signal reaching a value corresponding to any of the center and the extremity of the fluctuation when the robot arm moves to the determined position; characterised by identifying the position determined based on the center of a peak in a curve of the signal as the original point of the axis . receiving , during a movement of the robot arm in an axis of the robot arm , a signal collected by a sensor equipped at a frame of the robot arm ; detecting a change in strength of the received signal , the change being caused by an offset between a position of a reference mark equipped at the robot arm and a position of the sensor ; and determining an original point of the axis of the robot arm based on the detected change, wherein detecting the change in the strength of the signal comprises: detecting any of a center and an extremity of a fluctuation in the strength of the signal, wherein determining the original point of the axis further comprises: determining a position of the robot arm in the axis based on any of the center and the extremity of the fluctuation, the strength of the signal reaching a value corresponding to any of the center and the extremity of the fluctuation when the robot arm moves to the determined position; characterised by identifying the position determined based on the center of a peak in a curve of the signal as the original point of the axis . detecting any of a center and an extremity of a fluctuation in the strength of the signal, wherein determining the original point of the axis further comprises: determining a position of the robot arm in the axis based on any of the center and the extremity of the fluctuation, the strength of the signal reaching a value corresponding to any of the center and the extremity of the fluctuation when the robot arm moves to the determined position; characterised by identifying the position determined based on the center of a peak in a curve of the signal as the original point of the axis . determining a position of the robot arm in the axis based on any of the center and the extremity of the fluctuation, the strength of the signal reaching a value corresponding to any of the center and the extremity of the fluctuation when the robot arm moves to the determined position; characterised by identifying the position determined based on the center of a peak in a curve of the signal as the original point of the axis . <EOS>