Vacuum cleaner and method for controlling the same

1. A vacuum cleaner comprising:

a cleaner body including a moving device for moving, the moving device comprising a plurality of wheels and a plurality of motors for rotating the plurality of wheels;

a suction device connected to the cleaner body to suction dusts and air and guide the suctioned dusts and air to the cleaner body, the suction device comprising a handle;

a detection device configured to detect a distance between the handle and the cleaner body; and

a controller configured to determine whether movement of the cleaner body is necessary on the basis of the distance between the cleaner body and the handle, the controller controlling the moving device when the movement of the cleaner body is necessary,

wherein the controller controls the moving device to allow the cleaner body to avoid an obstacle when it is determined that an operation for avoiding the obstacle is necessary while the moving device operates,

wherein the vacuum cleaner further comprises a plurality of current detectors configured to detect current inputted into each of the plurality of motors,

wherein the controller is configured to determine whether the operation for avoiding the obstacle is necessary on the basis of the current detected by at least one current detector of the plurality of current detectors, and

wherein the controller is configured to drive the moving device to allow the cleaner body to avoid the obstacle,

wherein the detection device comprises:

an ultrasonic transmitting unit disposed on the suction device to transmit ultrasonic waves, and

an ultrasonic receiving unit disposed on the cleaner body to receive the ultrasonic waves transmitted from the ultrasonic transmitting unit,

wherein the controller determines whether the operation for avoiding the obstacle is necessary on the basis of an intensity of the ultrasonic waves received into the ultrasonic receiving unit and the current detected by the at least one current detector of the plurality of current detectors, and

wherein the controller determines that the operation for avoiding the obstacle is necessary when a ratio of the current detected by the at least one current detector to the intensity of the ultrasonic waves is less than a reference ratio.

2. The vacuum cleaner according to claim 1 , wherein the controller determines that the operation for avoiding the obstacle is necessary when the current detected by the at least one current detector of the plurality of current detectors is above a threshold current while the current is applied to the at least one motor of the plurality of motors.

3. The vacuum cleaner according to claim 1 , further comprising an obstacle detector disposed on the cleaner body to detect the obstacle,

wherein, when the obstacle is detected by the obstacle detector while the cleaner body is moved, the controller determines that the operation for avoiding the obstacle is necessary.

4. The vacuum cleaner according to claim 1 , wherein the controller drives the moving device to allow the cleaner body to be moved backward so that the cleaner body avoids the obstacle.

5. The vacuum cleaner according to claim 4 , wherein the controller controls the moving device so that the cleaner body is rotated to a left or right side in a state in which the cleaner body is moved backward by a predetermined distance from the obstacle.

6. The vacuum cleaner according to claim 1 , wherein the controller drives the moving device to allow the cleaner body to be rotated to a left or right side while the cleaner body is moved backward so that the cleaner body avoids the obstacle.

7. The vacuum cleaner according to claim 1 , wherein, after the cleaner body avoids the obstacle, the controller determines again whether the movement of the cleaner body is necessary on the basis of information detected by the detection device.