The invention discloses an improved method and device for sensing orientation of an object in space in a Working Reference Frame. The device of the invention includes an angular velocity sensor with at least two sensing axes and a linear acceleration sensor with at least three sensing axes. The method used for sensing orientation of the object in space in the Working Reference Frame uses synthetic values of the gravity component of the acceleration of the object. It depends upon the number of sensing axes of the angular velocity sensor and upon the dynamicity of the movement of the object. The dynamicity of the movement of the object is tested to compute the synthetic values which are used. The method and device of the invention allow control of a cursor on a display, independently of the roll imparted to the device by a user, in a seamless manner which is greatly improved over the devices and methods of the prior art.