Patent ID: 8032978

Claim:
A robotic cleaning device, comprising: a main body, which accommodates: controllable drive means arranged to move the device over a surface, cleaning means arranged to clean the surface when the device is moved over the surface, obstacle detecting means, and a control device connected to the drive means and the obstacle detecting means, wherein the main body has a left side wall connecting a front end portion with a left rear end portion and a right side wall connecting the front end portion with a right rear end portion, the control device, when receiving information from the obstacle detecting means about a detected obstacle, is arranged to control the drive means to rotate the device around one of a main left-turn axis located where a left non-pivotable support wheel located at the left rear end portion contacts the surface, and a main right-turn axis located where a right non-pivotable support wheel located at the right rear end portion contacts the surface, such that the device performs substantially only turning motion round the one of said axes, wherein the left side wall and the right side wall are configured such that the device is moved clear of the detected obstacle by said turning motion; and wherein wherein at least a major portion of the left side wall is shaped as a circular arc having a first centre of curvature that coincides with the main right-turn axis, and at least a major portion of the right side wall is shaped as a circular arc having a first centre of curvature that coincides with the surface, within a circular arc having a second centre of curvature that coincides with the main left-turn axis, and wherein the maximum distance from the first centre of curvature to the left side wall is located proximal to the front end portion of the main body, and the maximum distance from the second centre of curvature to the right side wall is located proximal to the front end portion of the main body.