Abstract: An apparatus for and a method of preventing bumping and falling of an automatic travelling cleaner wherein a situation of the cleaner is determined by sensing a variation of flow rate of a fluid in an extension pipe depending on a gap between an intake port and a surface to be cleaned, thereby deriving a suction work ratio or sensing revolutions and a current value of a cleaning motor or a torque value of each travel motor, and then determining a travel, a bumping, and a step sensing, based on the sensed value. The present invention eliminates the provision of a plurality of sensors densely arranged around a cleaner and adapted to sense bumping and falling of the cleaner and thus eliminates the requirement of additional devices for the sensors. This reduces the manufacture costs.

Abstract: A method for automatically controlling a travelling and cleaning operation of a vacuum cleaner.

Abstract: This invention relates to an obstacle sensing apparatus for a self-propelled cleaning robot which is capable of accurately sensing the position of an obstacle without the influence of ultrasonic directivity, and which comprises mounting members (22) disposed at both sides of the front portion of a body(11) of the robot; each made of a three-sided plate including a central portion facing forwardly of the body(11), one side portion bent at an angle of 90.degree. relative to the central portion, and one side portion inclined at an angle of 45.degree. relative to the central portion; ultrasonic distance-measuring means disposed in each portion of each mounting member(22) and an ultrasonic distance-measuring circuit (27) to which the ultrasonic elements are connected; and control means for judging presence and absence of an obstacle on the basis of the output of the ultrasonic distance-measuring means, thereby controlling the direction of travel of the body(11).