Patent ID: 8386089

Claim:
A method of teleoperating an unmanned ground vehicle having a control unit, a first drive unit, a second drive unit and a pan camera, arranged in front of or behind the nominal centre of rotation (z) of the vehicle, the method comprising the steps of: an operator controlling the rotation of the camera decoupled from the vehicle rotation and controlling the motion of the vehicle in each time instant based upon an orientation of the camera so that what is seen in the centre of the camera image is reached by a command to move the vehicle, and said control unit calculating, based upon a command signal for the movement of the vehicle, a first and a second control signal to the respective drive units that will move the vehicle according to the command signal, and a third control signal to the camera counter-acting the movement of the vehicle so that the orientation of the camera is not affected by the movement of the vehicle, said command signal including information on speed (s 1 , s 2 ) and the angular velocity (s ω ) of the camera relative to a camera-fixed coordinate system; calculating the velocity of the first and the second drive unit by the control unit as follows: ( v 1 v 2 ) = ( 1 / 2 1 / 2 L / b - L / b ) - 1 ⁢ ( cos ⁢ ⁢ ϕ - sin ⁢ ⁢ ϕ sin ⁢ ⁢ ϕ cos ⁢ ⁢ ϕ ) ⁢ ( s 1 s 2 ) where b is the distance between the drive units, L is the distance from the nominal centre of rotation z to the camera and φ the angle of the camera relative to the vehicle; calculating the angular velocity of the camera relative to the vehicle by the control unit as follows: k = s ω - θ . = s ω - v 1 - v 2 b where θ is the orientation of the vehicle relative to an earth-fixed coordinate system; the first and the second control signal containing information on the velocity (v 1 , v 2 ) of the respective drive units; the third control signal containing information on the angular velocity (k) of the camera relative to the vehicle.