Tool for accessing satellite fill/drain valves during propellant resupply

1. A tool mounted on a first satellite for opening rotationally removable access components of a second satellite, the access components on the second satellite having rotatable and static features coaxially aligned along a first axis, comprising:

a housing including

a motor mounted in said housing, a gear shifter coupled to said motor,

a wrench mounted in said housing including at least first and second adjustable wrench mechanisms coaxially aligned one on top of the other along a second axis, each of said first and second adjustable wrench mechanisms is configured to engage the access components with features of different sizes;

a differential gearbox mounted in said housing coupled to said at least first and second adjustable wrench mechanisms, the gearbox being configured to split the torque received by the gear shifter evenly between said at least first and second adjustable wrench mechanisms; and

wherein, when the tool is positioned with the wrench down over the access components with the second axis coincident with the first axis, the first adjustable wrench mechanism engages the rotatable feature of the rotationally removable access components and the second adjustable wrench mechanism engages the static feature of the access components such that the wrench applies equal and opposite forces to the rotatable feature and the static feature to apply bi-directional torque to the rotatable feature while reacting the torque on the static feature.

2. The tool according to claim 1 wherein said differential gearbox is coupled to said at least two adjustable wrench mechanisms via at least first and second shafts, the gear shifter being coupled to said gearbox, the gear shifter being configured to transmit torque from said motor to said gearbox, said gearbox being configured to transmit said torque received from said gear shifter to said at least first and second output shafts.

3. The tool according to claim 2 wherein said tool is a tool for exchanging one or more fluids between first and second satellites in orbit, the tool being mounted on said first satellite, the rotationally removable access components on the second satellite including at least one fill/drain valve having the rotatable features and static features, including a fluid exchanger subsystem mounted in said housing and configured to mate with one or more fluid sources on the first satellite and to selectively pass fluid between the first and second satellites, wherein the gear shifter is coupled to said fluid exchanger subsystem.

4. The tool according to claim 3 wherein the at least one fill/drain valve includes a rotationally removable secondary seal fitting with an associated rotatable feature coaxially aligned with the rotatable and static features of the fill/drain valve, wherein said wrench includes at least a third adjustable wrench mechanism being aligned coaxially with the first and second adjustable wrench mechanisms, said differential gear box including a third output shaft, said third output shaft being coupled to said third adjustable wrench mechanism, said third adjustable wrench mechanism being configured to engage the associated rotatable features of the secondary seal fitting to apply bi-directional torque thereto while the second adjustable wrench mechanism reacts this bi-directional torque on the static features on the fill/drain valve.

5. The tool according to claim 4 wherein said third adjustable wrench mechanism is configured to grasp said secondary seal fitting and to secure it once the applied torque has disengaged it from the fill/drain valve.

6. The tool according to claim 4 wherein said differential gear box is a shifting differential gear box in which an operator can selectively shift between differentially paired output shafts.

7. The tool according to claim 4 wherein said differential gear box is a shifting differential gear box in which an operator can selectively shift between said first and second output shafts and said second and third output shafts.

8. The tool according to claim 7 including an actuator configured to selectively engage said gear shifter for shifting between gear positions in said differential gear box.

9. The tool according to claim 8 wherein said actuator is a linear actuator mounted on an end effector and is configured for remote teleoperator control which, when commanded by an operator, engages said gear shifter to move said gear shifter between selected gears of the gearbox.

10. The tool according to claim 8 wherein said actuator is mounted on said housing and is configured for remote teleoperator control which, when commanded by an operator, engages said gear shifter to move said gear shifter between selected gears of the gearbox.

11. The tool according to claim 4 wherein each adjustable wrench mechanism includes a housing having a rotational axis, a pair of opposed nut cams pivotally mounted each to a toothed cam lock, said nut cams each including a pawl member, said cam locks being translationally mounted to a cam ring, said cam ring coaxially mounted in said housing and being rotationally movable with respect to said housing, a detent spring mounted between said cam ring and said housing to restrict movement of said cam ring, a toothed drive ring having inner and outer toothed surfaces mounted in said housing and being rotatable with respect to said housing, said cam pawls being engaged with said toothed drive ring so that when said toothed drive ring is rotated by an output shaft from said differential gear box, said nut cams are rotationally driven until they contact opposing outer surfaces of a faceted rotatable element, at which point said toothed cam locks slide radially outward to engage a toothed inner surface of said toothed drive ring thereby locking the drive ring and the cam ring together to permit torque applied by said output shaft to be transmitted to said faceted surface.

12. The tool according to claim 1 wherein said wrench is mounted adjacent to a first end of said housing, said first end of said housing being configured to allow engagement of said wrench with said rotationally removable access components, and including a vision system mounted on said housing disposed, and having a field of view, to observe a region around said first end of said housing to observe the engagement of the wrench with the rotationally removable access components to allow remote operator control of said wrench.

13. The tool according to claim 3 wherein the second satellite is configured to receive at least two different fluids and includes at least a first fill/drain valve and a second fill/drain valve each having different coupling features, and wherein said fluid exchanger subsystem mounted in said housing includes at least two fluid flow pathways having corresponding coupling features associated with each to mate with the first and second fill/drain valves which are configured to prevent inadvertent mixing of said at least two different fluids.

14. The tool according to claim 13 wherein fluid exchanger subsystem is configured to be movable between at least two positions in said housing such that when in a first position a first of the at least two fluid flow pathways is coupled to a first fluid source on the first satellite and the first fill/drain valve then the second of said at least two fluid flow pathways is disengaged from the second fill/drain valve and from a second fluid source on the first satellite, and wherein when in a second position the second fluid flow pathway is coupled to the second fluid source on the first satellite and the second fill/drain valve then the first fluid flow pathway is disengaged from the first fill/drain valve and from the first fluid source on the first satellite, and wherein said fluid exchanger subsystem includes an interface adapted to be engaged by said motor for moving said fluid exchanger subsystem between said first and second positions.

15. The tool according to claim 1 including features mounted on said housing to allow the tool to be grasped and manipulated by an end effector mounted on a distal end of a robotic arm, said features includes a grapple fixture.

16. The tool according to claim 15 wherein said housing includes at least one power and data connector, at least one fluid coupling connected to at least one fluid flow path from at least one fluid storage tank on said first satellite, and wherein said at least one power and data connector, and said at least one fluid coupling are positioned to mate with corresponding power and data connector and fluid flow coupling on said end effector.

17. The tool according to claim 16 wherein said power and data connector on said housing is connected to said motor for providing power to said motor, and for providing power and a data connection to various sensors including a vision system mounted to said housing for transmitting image data from said vision system to a communication system on said first satellite for transmitting the image data to a remote operator and for receiving instructions from said remote operator for commanding said motor, said vision system disposed, and having a field of view, to observe a region around a first end of said housing to observe the engagement of the wrench with the rotationally removable access components to allow remote operator control of said wrench.

18. The tool according to claim 17 wherein said end effector includes at least a first actuator configured such that when the tool is grasped by the end effector and said first actuator is activated, said at least one electrical connector on said end effector is advanced and plugged into said at least one electrical connector on said housing, and including a second actuator configured such that when the tool is grasped by the end effector and said second actuator is activated, said at least one data connector on said end effector is advanced and plugged into said at least one data connector on said housing, and including a third actuator configured such that when the tool is grasped by the end effector and said third actuator is activated said at least one fluid coupling on said end effector is advanced and mated to a fluid exchanger subsystem in said second satellite.

19. The tool according to claim 1 wherein said housing includes thermal insulation and temperature controllers for controlling a temperature of the housing.

20. The tool according to claim 1 including sensing means incorporated into said housing for sensing locations of designated moving parts.

21. The tool according to claim 11 wherein said each nut cam includes a cam face, and wherein when said adjustable wrench mechanism is rotated within said housing over a fill/drain valve the cam faces on the two nut cams move towards each other until they contact the features on the fill/drain valve.