Method for teleoperating an unmanned ground vehicle with a pan camera and such a ground vehicle

• US 8,386,089 B2
• Filed: 02/12/2007
• Issued: 02/26/2013
• Est. Priority Date: 02/17/2006
• Status: Expired due to Fees

• Current Assignee: Totalforsvarets Forskningsinstitut (FOI)
• Original Assignee: Totalforsvarets Forskningsinstitut (FOI)
• Inventors: gren, Petter
• Primary Examiner(s): Zanelli, Michael J.
• Application Number:
  US12/223,924
• Publication Number:
  US 20100138079A1
• Time in Patent Office: 2,206 Days
• Field of Search: None
• US Class Current: 701/2
• CPC Class Codes: G05D 1/0038 by providing the operator with simple or augmented images from one or more cameras located onboard the vehicle, e.g. tele-operation images analyzed by a computer and used for automatic navigation G05D1/0246

Abstract

A method is provided for 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 center of rotation (z) of the vehicle. The operator controls the translation and rotation of the camera, and thus his field of vision, relative to a camera-fixed coordinate system, and the movement of the vehicle is calculated to perform this camera movement. Consequently, the operator can in most cases ignore the vehicle dynamics and experience the feeling of controlling a floating camera. An unmanned ground vehicle with a control unit which performs the method is also provided.

Claims

1. 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 (s₁, s₂) 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;

2. The method as claimed in claim 1, wherein the first and the second drive unit include tracks.

3. The method as claimed in claim 1, wherein the first and the second drive unit each include one or more drive wheels.

4. The method as claimed in claim 1, wherein the vehicle includes a navigation sensor that measures the movement of the vehicle and compares said movement with the control signals of the operator and transmits correction signals to the control unit to compensate for differences.

5. The method as claimed in claim 1, wherein the ratio L/b is greater than ⅓

, where b is the distance between the drive units, L is the distance from the nominal centre of rotation (z) to the camera.

6. The method as set forth in claim 1, wherein the vehicle includes a navigation sensor that measures the movement of the vehicle and compares said movement with the control signals of the operator and transmits correction signals to the control unit to compensate for differences.

7. The method as set forth in claim 1, wherein the ratio L/b is greater than ⅓

, where b is the distance between the drive units, L is the distance from the nominal centre of rotation (z) to the camera.

8. 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, said 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;

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 control signal containing information on acceleration (s₁, s₂) and the angular velocity (s_ω

) of the camera relative to a camera-fixed coordinate system;

calculating the force and the torque of the first and the second drive unit as follows;

9. The method as claimed in claim 8, wherein the first and the second drive unit include tracks.

10. The method as claimed in claim 8, wherein the first and the second drive unit each include one or more drive wheels.

11. A method of teleoperating an unmanned ground vehicle having a navigation sensor, a first drive unit, a second drive unit, a control unit and a pan camera, arranged in front of or behind the nominal centre of rotation (z) of the vehicle, said 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;

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 navigation sensor measuring the movement of the vehicle and comparing said movement with the control signals of the operator and transmitting correction signals to the control unit to compensate for differences.

12. An unmanned ground vehicle comprising 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, 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;

said vehicle further including a control unit which, based upon a command signal for the movement of the vehicle, calculates 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 that counter-acts the movement of the vehicle so that the orientation of the camera is not affected by the movement of the vehicle; and

said vehicle further including a navigation sensor that measures the movement of the vehicle and compares said movement with the control signals of the operator and transmits correction signals to the control unit to compensate for differences.

13. The unmanned ground vehicle as claimed in claim 12, wherein the first and the second drive unit include tracks.

14. The unmanned ground vehicle as claimed in claim 12, wherein the first and the second drive unit each include one or more drive wheels.

15. The unmanned ground vehicle as claimed in claim 12, wherein the command signal includes information on speed (s₁, s₂) and the angular velocity (s_ω

) of the camera relative to a camera-fixed coordinate system;

the velocity of the first and the second drive unit is calculated by the control unit as follows;

16. The unmanned ground vehicle as claimed in claim 15, wherein the ratio L/b is greater than ⅓

, where b is the distance between the drive units, L is the distance from the nominal centre of rotation (z) to the camera.

17. The unmanned ground vehicle as set forth in claim 12, wherein the command signal contains information on acceleration (s₁, s₂) and the angular velocity (s_ω

) of the camera relative to a camera-fixed coordinate system;

the force and the torque of the first and the second drive unit are calculated as follows;