Small unmanned ground vehicle
The present teachings relate generally to a small remote vehicle having rotatable flippers and a weight of less than about 10 pounds and that can climb a conventional-sized stairs. The present teachings also relate to a small remote vehicle can be thrown or dropped fifteen feet onto a hard/inelastic surface without incurring structural damage that may impede its mission. The present teachings further relate to a small remote vehicle having a weight of less than about 10 pounds and a power source supporting missions of at least 6 hours.
1. A mobile robot, comprising:
a housing having a forward end, a rearward end, and a center of gravity;
a driven support surface movably connected to each side of the housing and configured to propel the housing in at least a forward direction, each driven support surface comprising a flexible track trained about a pair of wheels, each longitudinal support surface having a front end and a rear end, a longitudinal length from the front end to the rear end;
a flipper rotatably connected to each side of the housing rearward of the center of gravity of the housing, the flippers being configured to rotate in a first direction to raise the rearward end of the robot and to rotate in a second and opposite direction to raise the forward end of the robot housing;
a flipper motor, to provide a rotational force to rotate the flippers; and
a flipper drive gear configured to translate a rotational force from the flipper motor to the flipper on at least one of the sides via a slip clutch;
wherein the slip clutch comprises:
a slotted cylindrical protrusion configured to surround an axle that drives the flippers;
a collar surrounding the slotted cylindrical protrusion to clamp the slotted cylindrical protrusion to the axle at a predetermined torque corresponding to a slip torque.
2. The mobile robot of claim 1 , wherein:
the driven support surface movably connected to each side of the housing comprises a first driven support surface movably connected to a first side of the housing, and a second driven support surface movably connected to a second side of the housing;
the flipper rotatably connected to each side of the housing comprises a first flipper rotatably connected to the first side of the housing, and a second flipper rotatably connected to the second side of the housing;
and
a sensor mounted to the first side of the housing, wherein at least a portion of a field of view of the sensor extends in a direction away from the first side and passes through a hole in the first flipper in at least a first position of the first flipper.
3. A mobile robot system having a weight of less than about 10 pounds, the mobile robot system comprising:
the mobile robot of claim 2 , the mobile robot having a weight of less than about 5 pounds;
an operator control unit configured to communicate with the mobile robot and comprising:
a housing;
an antenna supported by the housing and configured to transmit to and receive signals from the mobile robot;
a display configured to provide information regarding the operation of the mobile robot; and
an input device coupled to the display and configured to receive operator input.
4. The mobile robot system of claim 3 , wherein the housing of the operator control unit comprises a recess in a portion of the housing to accommodate an operator's substantially cylindrical forearm to support the housing during operation of the robot system.
5. The mobile robot system of claim 3 , further comprising a docking station configured to accommodate the mobile robot and the operator control unit.
6. The mobile robot system of claim 2 , wherein the at least a portion of the field of view extends in a direction substantially parallel to the ground.
7. The mobile robot of claim 2 , wherein the sensor comprises a radiation source, and the hole prevents the first flipper from blocking at least a portion of the field of view of the radiation source in at least the first position of the first flipper.
8. The mobile robot of claim 2 , wherein the sensor comprises a camera.
9. The mobile robot of claim 2 , wherein the first position coincides with a stowed position of the first flipper.
10. The mobile robot of claim 2 , wherein at least one of the first and second flippers has a transparent portion to prevent the flipper from blocking at least a portion of the field of view of at least one camera and/or wall-following sensor mounted to the first or second side.
11. The mobile robot of claim 2 , wherein at least one of the first and second flippers comprises a necked taper to reduce coverage, by the flipper, of at least one camera mounted to the first or second side.
12. The mobile robot of claim 2 , wherein the sensor comprises a wall-following sensor.
13. A method for operating a mobile robot, the method comprising:
driving a first support surface movably connected to a first side of a housing of the mobile robot, and driving a second support surface movably connected to a second side of the housing, the first and second support surfaces propelling the housing in at least a forward direction, each of the first and second driven support surfaces comprising a flexible track trained about a pair of wheels;
rotating a first flipper connected to the first side of the housing rearward of the center of gravity of the housing, and rotating a second flipper connected to the second side of the housing rearward of the center of gravity of the housing, the first and second flippers being rotated in a first direction to raise a rearward end of the housing;
wherein the first and second flippers are rotated using at least one flipper motor providing a rotational force to rotate the first and second flippers, and using a flipper drive gear translating a rotational force from the at least one flipper motor to the first and second flippers via at least one slip clutch; and
wherein the slip clutch comprises:
a slotted cylindrical protrusion configured to surround an axle that drives the flippers;
a collar surrounding the slotted cylindrical protrusion to clamp the slotted cylindrical protrusion to the axle at a predetermined torque corresponding to a slip torque.
14. The method of claim 13 , further comprising:
operating a sensor mounted to the first side of the housing and having a field of view extending from the first side of the housing in a direction away from the first side, the first flipper having a hole preventing the first flipper from blocking at least a portion of the field of view of the sensor in at least a first position of the first flipper; and
rotating the first and second flippers in a second direction opposite to the first direction, to raise a forward end of the housing.
15. The method of claim 13 , further comprising:
operating a sensor mounted to the first side of the housing and having a field of view extending from the first side of the housing in a direction away from the first side, the first flipper having a hole preventing the first flipper from blocking at least a portion of the field of view of the sensor in at least a first position of the first flipper;
wherein the sensor comprises a camera.
16. The method of claim 15 , wherein at least one of the first and second flippers has a transparent portion to prevent the flipper from blocking at least a portion of the field of view of at least one camera and/or wall-following sensor mounted to the first or second side.
17. The method of claim 13 , further comprising:
operating a sensor mounted to the first side of the housing and having a field of view extending from the first side of the housing in a direction away from the first side, the first flipper having a hole preventing the first flipper from blocking at least a portion of the field of view of the sensor in at least a first position of the first flipper;
wherein the sensor comprises a wall-following sensor.
18. The method of claim 13 , wherein the mobile robot comprises a wall-following sensor, wherein at least one of the first and second flippers has a transparent portion to prevent the flipper from blocking at least a portion of the field of view of the wall-following sensor.
19. The method of claim 13 , wherein the mobile robot comprises a wall-following sensor, wherein at least one of the first and second flippers comprises a necked taper to reduce coverage of the wall-following sensor by the flipper.
20. The method of claim 13 , further comprising:
operating a sensor mounted to the first side of the housing and having a field of view extending from the first side of the housing in a direction away from the first side, the first flipper having a hole preventing the first flipper from blocking at least a portion of the field of view of the sensor in at least a first position of the first flipper;
wherein the first position coincides with a stowed position of the first flipper.