Robotic Platform

• US 20090107738A1
• Filed: 12/31/2008
• Published: 04/30/2009
• Est. Priority Date: 03/27/1998
• Status: Active Grant

• Current Assignee: Flir Detection, Inc. (Teledyne Technologies Incorporated)
• Original Assignee: iRobot Corporation
• Inventors: Won, Chikyung
• Granted Patent: US 9,248,874 B2
• Time in Patent Office: Days
• US Class Current: 180/8.700
• CPC Class Codes: B25J 11/0025 handling explosives, bombs or hazardous objects
• CPC Class Codes: B25J 5/005 mounted on endless tracks or belts
• CPC Class Codes: B62D 55/065 Multi-track vehicles, i.e. more than two tracks soil-shifting machines E02F; mining machines E21C
• CPC Class Codes: B62D 55/0655 Articulated endless track vehicles steering specially adapted for trailers B62D13/00; articulated buses B62D47/025; tractor-trailer combinations or road trains comprising a uni-axle unit and a uni-axle trailer B62D53/02
• CPC Class Codes: B62D 55/075 Tracked vehicles for ascending or descending stairs, steep slopes or vertical surfacesmagnetic or pneumatic ground-engaging parts B62D55/265; chairs or multi-track cycles specially adapted for invalids A61G5/00
• CPC Class Codes: B62D 55/12 Arrangement, location, or adaptation of driving sprockets
• CPC Class Codes: B62D 55/14 Arrangement, location, or adaptation of rollers
• CPC Class Codes: B62D 55/244 Moulded in one piece, with either smooth surfaces or surfaces having projections, e.g. incorporating reinforcing elements
• CPC Class Codes: Y10S 180/901 Devices for traversing vertical surfaces
• CPC Class Codes: Y10S 280/901 Adaptation of nonspecialized vehicles to semitrailer tractors

Abstract

An articulated vehicle including a main frame, a drive system disposed on the main frame, and at least one arm having a proximal end and a distal end. The proximal end of the at least one arm being pivotally coupled to the main frame and the distal end being pivotable above the surface. The vehicle also including an articulator motor disposed on the main frame and coupled to the at least one arm for pivoting the at least one arm above the surface and about the transverse axis, and a slip clutch coupled between the articulator motor and the at least one front arm for enabling rotation of the at least one front arm without rotation of the articulator drive motor when a torque between the at least one front arm and the main frame exceeds a threshold torque.

Claims

1. An articulated vehicle comprising:

a main frame having right and left sides;

a drive system disposed on the main frame and configured to maneuver the articulated vehicle over a surface;

at least one arm having a proximal end and a distal end, the proximal end of the at least one arm being pivotally coupled to the main frame about a transverse axis generally perpendicular to the sides of the main frame and the distal end being pivotable above the surface;

an articulator motor disposed on the main frame and coupled to the at least one arm for pivoting the at least one arm above the surface and about the transverse axis; and

a slip clutch coupled between the articulator motor and the at least one front arm, the slip clutch enabling rotation of the at least one front arm without rotation of the articulator drive motor when a torque between the at least one front arm and the main frame, caused by an external force acting on the at least one arm by forceful contact with the surface or an environmental feature above the surface, exceeds a threshold torque that can be provided by the articulator motor.

2. The articulated vehicle of claim 1, wherein the slip clutch comprises at least one slip clutch adjuster for altering the threshold torque deliverable by the articulator motor to the arms.

3. The articulated vehicle of claim 1, wherein the slip clutch slips in excess of a torque of approximately 127 N-m applied to the at least one arm permitting the front tracks to rotate with respect to the drive.

4. The articulated vehicle of claim 1, wherein the drive system comprises:

right and left main tracks disposed on corresponding sides of the main frame, each main track trained about a corresponding main drive pulley and a corresponding rear idler pulley; and

right and left track motors disposed on the main frame and differentially driving respective the main drive pulleys to provide skid steering.

5. The articulated vehicle of claim 4, wherein the at least one arm is mounted on a side of one of the main tracks opposite the main frame.

6. The articulated vehicle of claim 4, wherein the at least one arm is mounted between one of the main tracks and the main frame.

7. The articulated vehicle of claim 4, wherein the at least one arm further comprises:

an arm drive pulley concentric with and coupled to rotate in unison with the corresponding main drive pulley,

an arm side plate mounted to extend from the arm drive pulley, beside the main frame,

an arm idler pulley rotatably mounted at a distal end of the arm side plate, and

an arm track trained about the arm drive pulley and the arm idler pulley.

8. The articulated vehicle of claim 4, wherein the main frame is contained within a volume defined by the main tracks and is symmetrical about a horizontal plane, thereby allowing inverted operation of the articulated vehicle.

9. The articulated vehicle of claim 4, wherein the combination of main tracks and the at least one arm provide an extended base sufficiently long to span a minimum of two stair steps of 7 in (17.8 cm) rise by 11 in (27.9 cm) tread stairs at all times, and the center of gravity of the articulated vehicle is located so that the articulated vehicle remains statically stable as it climbs stair steps of 7 in (17.8 cm) rise by 1 in (27.9 cm) tread stairs.

10. The articulated vehicle of claim 1, wherein the at least one arm is configured to rotate 360°

about the transverse axis.

11. The articulated vehicle of claim 10, wherein a center of mass of the articulated vehicle is contained within an envelope of the 360 degree rotation of the at least one arm;

and

wherein the articulator motor is configured to apply a torque to its coupled arm to;

(a) reach an upright mobility position of the articulated vehicle by pivoting the at least one arm from a stowed position next to the main frame downward and away from the main frame, raising and supporting the main frame on the at least one arm, and (b) perform a self-righting maneuver from the upright mobility position by pivoting the at least one arm to drive the upright main frame past a vertical position, causing the articulated vehicle to fall over and thereby invert the main frame.

12. The articulated vehicle of claim 10, further comprising a drive that couples the articulator motor to the slip clutch, the slip clutch being coupled to an articulator axle coupled to the at least one arm to rotate the at least one arm about the transverse axis, the drive providing a gear reduction between the articulator motor and the articulator axle.

13. The articulated vehicle of claim 1, further comprising a camera housed in a front portion of the of the main frame and arranged to provide a forward field of view along a driving direction of the vehicle, the forward field of view being unobstructed by movement of the at least one arm.

14. A method of operating an articulated vehicle, the method comprising:

driving an articulated vehicle along a drive direction over a surface, the vehicle comprising;

a main frame having right and left sides;

a drive system disposed on the main frame and configured to maneuver the articulated vehicle over the surface;

at least one arm having a proximal end and a distal end, the proximal end of the at least one arm being pivotally coupled to the main frame about a transverse axis generally perpendicular to the sides of the main frame and the distal end being pivotable above the surface;

an articulator motor disposed on the main frame and coupled to the at least one arm for pivoting the at least one arm above the surface and about the transverse axis; and

a slip clutch coupled between the articulator motor and the at least one front arm;

pivoting the at least one arm at an angle with respect to the articulator motor; and

receiving a torque between the at least one front arm and the main frame, caused by an external force acting on the at least one arm by forceful contact with the surface or an environmental feature above the surface;

wherein the slip clutch enables rotation of the at least one front arm without rotation of the articulator drive motor when the applied torque between the at least one front arm and the main frame exceeds a threshold torque that can be provided by the articulator motor.

15. The method of claim 14, wherein driving the articulated vehicle along a drive direction comprises negotiating a set of stairs.

16. The method of claim 15, wherein receiving a front impact to the at least one arm comprises impacting a stair of the set of stairs.

17. The method of claim 15, wherein receiving a front impact to the at least one arm comprises impacting a landing upon descending the set of stairs.

18. The method of claim 15, wherein negotiating a set of stairs comprises negotiating at least one stair of the set of stairs having a rise of at least 7 inches (17.8 cm) and a tread of at least 11 inches (27.9 cm).

19. The method of claim 14, wherein driving the articulated vehicle along a drive direction comprises traversing debris.

20. The method of claim 19, wherein receiving a front impact to the at least one arm comprises impacting the debris.