Office Action 1: Non-Final Rejection (2024-11-27)
Rejection types: 112 - Written Description/Enablement

CLAIMS:
What is claimed is:
1\. A servicer satellite configured to perform rendezvous with a client satellite, the servicer satellite comprising: a body comprising an X axis with a +X direction and a -X direction, a Y axis with a +Y direction and a -Y direction, and a Z axis with a +Z direction and a -Z direction; a set of thrusters comprising: i) a first thruster coupled to the body, ii) a second thruster coupled to the body, iii) a third thruster coupled to the body, and iv) a fourth thruster coupled to the body; a controller configured with commands to fire: i) the first thruster and the second thruster to produce a first thrust vector that reduces a separation distance between the servicer satellite and the client satellite and that removes an angular momentum or a rotational velocity of the body, and ii) the third thruster and the fourth thruster to produce a second thrust vector that reduces a rate of closure between the servicer satellite and the client satellite and that removes the angular momentum or the rotational velocity of the body; wherein: each of the thrusters are configured to provide 6 DOF thruster firing.
2\. The servicer satellite of claim 1, wherein each of the first thruster, the second thruster, the third thruster, and the fourth thruster are electric propulsion thrusters.
3\. The servicer satellite of claim 1, wherein: the controller is further configured to calculate and to follow a rendezvous trajectory that matches orbital parameters of the servicer satellite and the client satellite while firing the first thruster and the second thruster.
4\. The servicer satellite of claim 1, wherein: the controller is further configured to calculate and to follow a rendezvous trajectory that matches orbital parameters of the servicer satellite and the client satellite while firing the third thruster and the fourth thruster.
5\. The servicer satellite of claim 1, wherein: each of the first thruster and the second thruster are disposed at an aft panel of the body, the aft panel facing in the -Z direction.
6\. The servicer satellite of claim 5, wherein: each of the third thruster and the fourth thruster are disposed on a nadir panel of the body, the nadir panel positioned to face opposite to the aft panel.
7\. The servicer satellite of claim 1, wherein: each of the first thruster, the second thruster, the third thruster, and the fourth thruster are gimbled thrusters.
8\. The servicer satellite of claim 1, wherein: each of the first thruster, the second thruster, the third thruster, and the fourth thruster are configured to fire through a center of mass of the servicer satellite.
9\. The servicer satellite of claim 1, wherein: each of the first thruster, the second thruster, the third thruster, and the fourth thruster are configured to avoid firing through a center of mass of the servicer satellite.
10\. The servicer satellite of claim 1, wherein: each of the first thruster, the second thruster, the third thruster, and the fourth thruster are configured for orientation independent from one another.
11\. The servicer satellite of claim 1, wherein: each of the first thruster, the second thruster, the third thruster, and the fourth thruster are configured to fire simultaneously.
12\. The servicer satellite of claim 1, wherein: each of the first thruster, the second thruster, the third thruster, and the fourth thruster are configured to throttle.
13\. A servicer satellite comprising: a body comprising an X axis with a +X direction and a -X direction, a Y axis with a +Y direction and a -Y direction, and a Z axis with a +Z direction and a -Z direction; a set of thrusters comprising: i) a first thruster coupled to the body, ii) a second thruster coupled to the body, iii) a third thruster coupled to the body, and iv) a fourth thruster coupled to the body; and a controller configured with commands to: i) fire the first thruster and the second thruster to produce a first thrust vector that reduces a separation distance between the servicer satellite and the client satellite and that removes an angular momentum or a rotational velocity of the body, ii) fire the third thruster and the fourth thruster to produce a second thrust vector that reduces a rate of closure between the servicer satellite and the client satellite and that removes the angular momentum or the rotational velocity of the body; iii) calculate and follow a rendezvous trajectory that matches orbital parameters of the servicer satellite and the client satellite while firing the first thruster and the second thruster; and iv) calculate and follow the rendezvous trajectory while firing the third thruster and the fourth thruster; wherein: each of the thrusters are configured to provide 6 DOF thruster firing.
14\. A method of performing rendezvous with a client satellite, the method comprising: providing a servicer satellite comprising: a body comprising an X axis with a +X direction and a -X direction, a Y axis with a +Y direction and a -Y direction, and a Z axis with a +Z direction and a -Z direction; a set of thrusters comprising: i) a first thruster coupled to the body, ii) a second thruster coupled to the body, iii) a third thruster coupled to the body, and iv) a fourth thruster coupled to the body; and a controller configured to fire the set of thrusters; wherein: the controller fires the first thruster and the second thruster to produce a first thrust vector that reduces a separation distance between the servicer satellite and the client satellite and that removes an angular momentum or a rotational velocity of the body; and the controller fires the third thruster and the fourth thruster to produce a second thrust vector that reduces a rate of closure between the servicer satellite and the client satellite and that removes the angular momentum or the rotational velocity of the body; and each of the thrusters are configured to provide 6 DOF thruster firing.
15\. The method of claim 14, further comprising the step of: the controller calculates and follows a rendezvous trajectory that matches orbital parameters of the servicer satellite and the client satellite while firing the first thruster and the second thruster.
16\. The method of claim 14, further comprising the step of: the controller calculates and follows a rendezvous trajectory that matches orbital parameters of the servicer satellite and the client satellite while firing the third thruster and the fourth thruster.
17\. The method of claim 14, wherein: each of the first thruster and the second thruster are disposed at an aft panel of the body, the aft panel facing in the -Z direction.
18\. The method of claim 17, wherein: each of the third thruster and the fourth thruster are disposed on a nadir panel of the body, the nadir panel positioned to face opposite to the aft panel.
19\. The method of claim 14, wherein: each of the first thruster, the second thruster, the third thruster, and the fourth thruster are configured to fire simultaneously and are electric propulsion thrusters.
20\. The method of claim 14, wherein: each of the first thruster, the second thruster, the third thruster, and the fourth thruster are configured to throttle.

OFFICE ACTION:
DETAILED ACTION
Notice of Pre-AIA  or AIA  Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
This is the first Office Action on the merits. Claims 1-20 are pending and are addressed below.
Information Disclosure Statement
The information disclosure statement (IDS) filed on October 9, 2024 is in compliance with 37 CFR 1.97. Accordingly, the IDS has been considered by the Examiner. An initialed copy of the Form 1449 is enclosed herewith.
Drawings
The drawings are objected to under 37 CFR 1.83(a). The drawings must show every feature of the invention specified in the claims. In particular, each of independent Claims 1, 13, and 14 recite, “a set of thrusters comprising: i) a first thruster coupled to the body, ii) a second thruster coupled to the body, iii) a third thruster coupled to the body, and iv) a fourth thruster coupled to the body” and “each of the thrusters are configured to provide 6 DOF thruster firing” (emphasis added). The drawings appear to show thrusters with fixed outlets, but the drawings do not show the thrusters themselves as having structure for reorienting a position of the outlets. Instead, the drawings show the thrusters as being coupled to additional structure, such as extension arms, in order for the thrusters to be reoriented relative to the body of the servicer satellite. As such, the original drawings do not show the recited thrusters being “configured to provide 6 DOF thruster firing.” Therefore, the above-cited features must be shown or the features canceled from the claims. No new matter should be entered.
Corrected drawing sheets in compliance with 37 CFR 1.121(d) are required in reply to the Office action to avoid abandonment of the application. Any amended replacement drawing sheet should include all of the figures appearing on the immediate prior version of the sheet, even if only one figure is being amended. The figure or figure number of an amended drawing should not be labeled as “amended.” If a drawing figure is to be canceled, the appropriate figure must be removed from the replacement sheet, and where necessary, the remaining figures must be renumbered and appropriate changes made to the brief description of the several views of the drawings for consistency. Additional replacement sheets may be necessary to show the renumbering of the remaining figures. Each drawing sheet submitted after the filing date of an application must be labeled in the top margin as either “Replacement Sheet” or “New Sheet” pursuant to 37 CFR 1.121(d). If the changes are not accepted by the examiner, the applicant will be notified and informed of any required corrective action in the next Office action. The objection to the drawings will not be held in abeyance.
Claim Rejections - 35 USC § 112
The following is a quotation of the first paragraph of 35 U.S.C. 112(a):
(a) IN GENERAL.—The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor or joint inventor of carrying out the invention.
The following is a quotation of the first paragraph of pre-AIA  35 U.S.C. 112:
The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor of carrying out his invention.
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claims 1-20 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA  35 U.S.C. 112, the applicant), regards as the invention.
Independent Claims 1, 13 and 14 each recite, “each of the thrusters are configured to provide 6 DOF thruster firing.” It is noted that the present specification states that, “6 DOF refers to the six mechanical degrees of freedom of movement of a rigid body in three-dimensional space” (see Specification at 3). The present specification does not describe or define what “6 DOF thruster firing” encompasses or excludes, and the claims are rendered indefinite since “thruster firing” is an action rather than a structure. It is unclear what is required to meet the limitation of providing six degrees of freedom thruster firing. For example, does “6 DOF thruster firing” require that each thruster on its own has structure for reorienting itself with 6 DOF for firing in any orientation? Or does “6 DOF thruster firing” require that each thruster be capable of performing thruster firing that generates a thrust vector to reorient each respective thruster, or the body of the servicer satellite, with 6 DOF? For the purposes of examination, “6 DOF thruster firing” has been interpreted as requiring each thruster to have structure for reorienting itself with 6 DOF to perform thruster firing in any orientation.
Regarding Claim 13, line 10 recites, “the client satellite.” There is insufficient antecedent basis for this limitation in the claim.
The dependent claims not specifically addressed above are rejected as being dependent upon a rejected base claim.
Claims 1-20 are rejected under 35 U.S.C. 112(a) or 35 U.S.C. 112 (pre-AIA ), first paragraph, as failing to comply with the written description requirement. The claim(s) contains subject matter which was not described in the specification in such a way as to reasonably convey to one skilled in the relevant art that the inventor or a joint inventor, or for applications subject to pre-AIA  35 U.S.C. 112, the inventor(s), at the time the application was filed, had possession of the claimed invention.
In particular, independent Claims 1, 13 and 14 each recite, “each of the thrusters are configured to provide 6 DOF thruster firing.” It is noted that the specification on page 7, line 14, on page 8, line 19, and on page 9, line 1 each state, “each of the thrusters are configured to provide 6 DOF thruster firing.” However, the specification does not describe what structures or actions are required by the limitation “6 DOF thruster firing.” As discussed above in the 35 U.S.C. 112(b) Section, it is unclear what the limitation “6 DOF thruster firing” encompasses and has been interpreted as requiring each thruster to have structure for reorienting itself with 6 DOF to perform thruster firing in any orientation.
The present specification does not describe any configurations or structures of the thrusters that allow each respective thruster to move and reorient itself with six degrees of freedom. Instead, the specification describes each thruster being attached to separate structures, such as extension arms and gimbals, to perform 6 DOF maneuvers (see Specification at pages 2 and 22). In other words, the specification does not reasonably disclose any thrusters that are on their own “configured to provide 6 DOF thruster firing.” Therefore, the original disclosure does not reasonably convey to one skilled in the relevant art that the inventor was in possession of the above claimed subject matter at the time of filing.
The dependent claims not specifically addressed above are rejected as being dependent upon a rejected base claim.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
U.S. Patent No. 6,032,904 to Hosick et al. discloses a spacecraft with gimbaled electric thrusters (see FIG. 1C).
U.S. Publication No. 2017/0081048 to Glogowski et al. discloses mounting arrangements for thrusters to allow for six degrees of freedom (see para. 0026 and FIG. 4).
U.S. Publication No. 2023/0257137 to Freestone et al. discloses thrusters attached to boom to allow for 3, 4, 5, 6, or 7-degrees of freedom (see para. 0026 and FIGS. 1-3).

APPLICANT REBUTTAL: Remarks
This paper is submitted with respect to the Office Action mailed on 27 November 2024. Claims 1, 3, 4, 7, 13-18, and 20 are amended. No new matter has been added. There are no new claims. Therefore, claims 1-20 are pending.
Examiner Interview
Examiner Leung, Primary Examiner Zarroli and the undersigned held a brief telephone discussion on 31 January 2025. Among other things, proposed claim amendments to independent claim 1 were presented and discussed. Agreement was reached that the presented claim amendments to claim 1 appear to overcome all pending rejections, i.e. the 35 U.S.C. § 112(a) and 35 U.S.C. § 112(b) rejections, and the objection of the drawings under 37 C.F.R. @ 1.83(a). However, no agreement was reached regarding allowance of any claims because a new prior art search is required. The undersigned thanks Examiner Leung and Primary Examiner Zarroli for their time and guidance.
Objection to the Drawings under 37 C.F.R.
§
(a)
The drawings are objected to under 37 C.F.R. @ 1.83(a) because the drawings are
asserted to not show the recited thrusters feature of "configured to provide 6 DOE thruster firing." Without admission as to the validity of the objection and solely to facilitate prosecution, the feature at issue has been deleted from each of independent claims 1, 13, and 14 and thus the objection is moot. Therefore, the drawing objections being addressed, Applicant requests the drawing objections be withdrawn.
Claim Rejections Under 35 U.S.C.
§
112(a) and 35 U.S.C.
§
112(b)
Claims 1-20 are rejected under 35 U.S.C. § 112(a) and under 35 U.S.C. § 112(b) for failing to comply with the written description requirement and as being indefinite, respectively, with reference to the thruster feature "configured to provide 6 DOE thruster firing."
Without admission as to the validity of the § 112(a) and § 112(b) rejections and solely to facilitate prosecution, the feature at issue has been deleted from each of independent claims 1, 13, and 14 and therefore the rejections are moot.
Therefore, the rejections being addressed, Applicant requests the § 112(a) and § 112(b) rejections be withdrawn.
Independent Claim 1 Amendments with respect to Examiner Interview
Claim 1 is presented with the features presented during the Examiner Interview and therefore overcomes, per agreement, the pending set of 35 U.S.C. § 112(a) and 35 U.S.C. § 112(b) rejections and the objection of the drawings under 37 C.F.R. § 1.83(a). Therefore, independent claim 1 is allowable. Claims 2-6 and 8-12, depending from allowable claim 1, are therefore also allowable.
Further Claim Amendments to Independent Claim 1
Independent claim 1 has been further amended solely to facilitate prosecution and to further distinguish claim 1 from the prior art, to include, e.g., U.S. Pat. Publ. No. 2021/0078732 to Reitman ("Reitman"). Specifically, claim 1 recites, inter alia, the feature:
the controller further configured with commands to fire the first thruster and the second thruster to follow a rendezvous trajectory that matches orbital parameters of the servicer
satellite and the client satellite
This feature, at least, is not disclosed nor suggested by Reitman or any other prior art. Reitman, e.g., describes station keeping operations of a servicer satellite docked with a client satellite, and is silent regarding the rendezvous structure of a servicer satellite as recited in claim 1, to include the above feature.
Thus, this feature provides a further distinction to the prior art and provides further evidence that claim 1, and its dependent claims 2-6 and 8-12, are allowable.
Claim Amendments to Independent Claim 13
In addition to deleting the thruster feature "configured to provide 6 DOF thruster firing" as described above, independent claim 13 has been amended solely to facilitate prosecution and to further distinguish claim 13 from the prior art, to include, e.g., Reitman. Specifically, claim 13 recites, inter alia, the features1:
a controller configured with commands to:
... fire the first thruster and the second thruster to follow a rendezvous trajectory that matches
orbital parameters of the servicer satellite and the client satellite; and
a controller configured with commands to:
... fire the first thruster and the second thruster to accelerate the servicer satellite toward the
client satellite
These features, at least, are not disclosed nor suggested by Reitman or other prior art. Reitman, e.g., describes station keeping operations of a servicer satellite docked with a client satellite, and is silent regarding the servicer satellite structure as recited in claim 13, to include the above features.
Thus, such features provide further distinctions to the prior art and evidence that claim 13 and its dependent claim 7 are allowable.
Claim Amendments to Independent Claim 14
In addition to deleting the thruster feature "configured to provide 6 DOF thruster firing" as described above, independent claim 14 has been amended solely to facilitate prosecution and to further distinguish claim 14 from the prior art, to include, e.g., Reitman. Specifically, claim 14 recites, inter alia, the feature:
the controller fires the first thruster and the second thruster to follow a first rendezvous
trajectory that matches orbital parameters of the servicer satellite and the client satellite
1 The second highlighted feature finds support at least at pg. 25, 11. 14-26 of the application as filed, i.e., "Generally, the RvD phase of operation comprises thrusting along the positive Z axis for steering the LEXI toward the host satellite. An on-board satellite computer using on-board sensors computes the thrust profile (acceleration and deceleration) for the LEXI to execute. ... The two diagonal thrusters (for example Ni and S2) are fired continuously based on a trajectory profile calculated by the LEXI on board computer and guidance and control system. As long as the acceleration is needed, the two diagonal thrusters are operating and close the range between the LEXI and the Host satellite. In case the trajectory calls for deceleration or reaching a complete stop of the acceleration or producing an outer plane corrections in the X or Y directions, the two diagonal thrusters (for example Ni and S2) in the positive Z direction are turned off. Two other diagonal thrusters (for example N2 and Si) are used such that the thruster vector is in the negative Z direction for decelerating the LEXI.
This feature, at least, is not disclosed nor suggested by Reitman or other prior art.
Reitman, e.g., describes station keeping operations of a servicer satellite docked with a client satellite, and is silent regarding the rendezvous operations of a servicer satellite as recited in claim 14, to include the above feature.
Thus, this feature provides a further distinction to the prior art and provides further evidence that claim 14, and its dependent claims 15-20, are allowable.
Conclusion

NEXT OFFICE ACTION: Reasons for Allowance
Claims 1-20 are allowed.
The following is an examiner’s statement of reasons for allowance:
Regarding Claims 1-6 and 8-12, the prior art of record does not reasonably teach or suggest the combination of features of a servicer satellite configured to perform rendezvous with a client satellite including a controller configured with commands to fire: i) the first thruster and the second thruster to produce a first thrust vector that reduces a separation distance between the servicer satellite and the client satellite and that removes an angular momentum or a rotational velocity of the body, and ii) the third thruster and the fourth thruster to produce a second thrust vector that reduces a rate of closure between the servicer satellite and the client satellite and that removes the angular momentum or the rotational velocity of the body, the controller further configured with commands to fire the first thruster and the second thruster to follow a rendezvous trajectory that matches orbital parameters of the servicer satellite and the client satellite; wherein: the first thruster is coupled to at least one of a first hinge and a first gimble and the second thruster is coupled to at least one of a second hinge and a second gimble to enable the first thruster and the second thruster to position to produce the first thrust vector; and the third thruster is coupled to at least one of a third hinge and a third gimble and the fourth thruster is coupled to at least one of a fourth hinge and a fourth gimble to enable the third thruster and the fourth thruster to position to produce the second thrust vector
Regarding Claims 7 and 13, the prior art of record does not reasonably teach or suggest the combination of features of a servicer satellite including a set of thrusters comprising: i) a first thruster coupled to the body, ii) a second thruster coupled to the body, iii) a third thruster coupled to the body, and iv) a fourth thruster coupled to the body; and a controller configured with commands to: i) fire the first thruster and the second thruster to produce a first thrust vector that reduces a separation distance between the servicer satellite and the client satellite and that removes an angular momentum or a rotational velocity of the body, ii) fire the third thruster and the fourth thruster to produce a second thrust vector that reduces a rate of closure between the servicer satellite and the client satellite and that removes the angular momentum or the rotational velocity of the body; iii) fire the first thruster and the second thruster to follow a rendezvous trajectory that matches orbital parameters of the servicer satellite and the client satellite; and iv) fire the first thruster and the second thruster to accelerate the servicer satellite toward the client satellite.
Regarding Claims 14-20, the prior art of record does not reasonably teach or suggest the combination of steps of performing rendezvous by a servicer satellite including providing the servicer satellite comprising a controller configured with commands to fire the set of thrusters; wherein: the controller fires the first thruster and the second thruster to produce a first thrust vector that reduces a separation distance between the servicer satellite and a client satellite and that removes an angular momentum or a rotational velocity of the body; and the controller fires the third thruster and the fourth thruster to produce a second thrust vector that reduces a rate of closure between the servicer satellite and the client satellite and that removes the angular momentum or the rotational velocity of the body; and the controller fires the first thruster and the second thruster to follow a first rendezvous trajectory that matches orbital parameters of the servicer satellite and the client satellite.
Any comments considered necessary by applicant must be submitted no later than the payment of the issue fee and, to avoid processing delays, should preferably accompany the issue fee. Such submissions should be clearly labeled “Comments on Statement of Reasons for Allowance.”
Conclusion

CITED REFERENCE SUMMARIES: Ref US6032904A: Claims:
A system for performing at least one of a plurality of operations including orbit raising, north-south station keeping, and selective unloading of momentum wheels used for controlling the orientation of a three-axis stabilized spacecraft having roll, pitch, and yaw axes, and having a north face and a south face which when on station in orbit about the earth generally face north and south, respectively, said system comprising: first and second thrusters having first and second thrust vectors, respectively; first support means for mounting said first thruster adjacent said north face, said first thruster being positioned a spaced distance away from said north face in a first direction parallel to the pitch axis and a spaced distance away from the pitch axis in a second direction normal to the pitch axis; second support means for mounting said second thruster adjacent said south face, said second thruster being positioned a spaced distance away from said south face in a third direction opposite the first direction and a spaced distance away from the pitch axis in the second direction; and gimbal means pivotally mounting said first and second thrusters on said first and second support means, respectively, for selectively positioning the thrust vectors of said first and second thrusters, said gimbal means including a gimbal system including: a first gimbal for mounting said first thruster for pivotal movement about an axis parallel to the roll axis between a stowed inoperative position through an orbit raising position at which the first thrust vector is generally parallel to the yaw axis to a north-south station keeping position at which the first thrust vector is generally aligned with the center of mass of the spacecraft; and a second gimbal for mounting said second thruster for pivotal movement about an axis parallel to the roll axis between a stowed inoperative position through an orbit raising position at which the second thrust vector is generally parallel to the yaw axis to a north-south station keeping position at which the second thrust vector is generally aligned with the center of mass of the spacecraft.
first and second thrusters having first and second thrust vectors, respectively;
first support means for mounting said first thruster adjacent said north face, said first thruster being positioned a spaced distance away from said north face in a first direction parallel to the pitch axis and a spaced distance away from the pitch axis in a second direction normal to the pitch axis;
second support means for mounting said second thruster adjacent said south face, said second thruster being positioned a spaced distance away from said south face in a third direction opposite the first direction and a spaced distance away from the pitch axis in the second direction; and
gimbal means pivotally mounting said first and second thrusters on said first and second support means, respectively, for selectively positioning the thrust vectors of said first and second thrusters, said gimbal means including a gimbal system including: a first gimbal for mounting said first thruster for pivotal movement about an axis parallel to the roll axis between a stowed inoperative position through an orbit raising position at which the first thrust vector is generally parallel to the yaw axis to a north-south station keeping position at which the first thrust vector is generally aligned with the center of mass of the spacecraft; and a second gimbal for mounting said second thruster for pivotal movement about an axis parallel to the roll axis between a stowed inoperative position through an orbit raising position at which the second thrust vector is generally parallel to the yaw axis to a north-south station keeping position at which the second thrust vector is generally aligned with the center of mass of the spacecraft.
a first gimbal for mounting said first thruster for pivotal movement about an axis parallel to the roll axis between a stowed inoperative position through an orbit raising position at which the first thrust vector is generally parallel to the yaw axis to a north-south station keeping position at which the first thrust vector is generally aligned with the center of mass of the spacecraft; and
a second gimbal for mounting said second thruster for pivotal movement about an axis parallel to the roll axis between a stowed inoperative position through an orbit raising position at which the second thrust vector is generally parallel to the yaw axis to a north-south station keeping position at which the second thrust vector is generally aligned with the center of mass of the spacecraft.
A system as set forth in claim 1 wherein each of said first and second thrusters is an electric thruster.
wherein each of said first and second thrusters is an electric thruster.
A method of performing at least one of a plurality of operations of a three-axis stabilized spacecraft having roll, pitch, and yaw axes, and having a north face and south face which when on station in orbit generally face north and south, respectively, said method comprising the steps of: (a) pivotally mounting on a first support means a first thruster adjacent the north face of the spacecraft such that it is positioned a spaced distance away from the spacecraft in a first direction parallel to the pitch axis and a spaced distance away from the pitch axis in a second direction normal to the pitch axis and for pivotal movement about an axis parallel to the roll axis between a stowed inoperative position through an orbit raising position at which the first thrust vector is generally parallel to the yaw axis to a north-south station keeping position at which the first thrust vector is generally aligned with the center of mass of the spacecraft; (b) pivotally mounting a second thruster on a second support means adjacent the south face of the spacecraft such that it is positioned a spaced distance away from the south face in a third direction opposite the first direction and a spaced distance away from the pitch axis in the second direction and for pivotal movement about an axis parallel to the roll axis between a stowed inoperative position through an orbit raising position at which the second thrust vector is generally parallel to the yaw axis to a north-south station keeping position at which the second thrust vector is generally aligned with the center of mass of the spacecraft; and (c) selectively positioning the direction of the first and second thrusters on said first and second support means, respectively, for performing an operation.
(a) pivotally mounting on a first support means a first thruster adjacent the north face of the spacecraft such that it is positioned a spaced distance away from the spacecraft in a first direction parallel to the pitch axis and a spaced distance away from the pitch axis in a second direction normal to the pitch axis and for pivotal movement about an axis parallel to the roll axis between a stowed inoperative position through an orbit raising position at which the first thrust vector is generally parallel to the yaw axis to a north-south station keeping position at which the first thrust vector is generally aligned with the center of mass of the spacecraft;
(b) pivotally mounting a second thruster on a second support means adjacent the south face of the spacecraft such that it is positioned a spaced distance away from the south face in a third direction opposite the first direction and a spaced distance away from the pitch axis in the second direction and for pivotal movement about an axis parallel to the roll axis between a stowed inoperative position through an orbit raising position at which the second thrust vector is generally parallel to the yaw axis to a north-south station keeping position at which the second thrust vector is generally aligned with the center of mass of the spacecraft; and
(c) selectively positioning the direction of the first and second thrusters on said first and second support means, respectively, for performing an operation.
A method as set forth in claim 3 wherein step (c) includes the steps of: (d) aligning the first and second thrusters, respectively, so as to be generally parallel to the yaw axis; (e) positioning the spacecraft to thereby generally align the yaw axis in the direction of desired thrust of the spacecraft as it orbits the earth; (f) simultaneously operating the first and second thrusters to achieve a desired new orbit.
wherein step (c) includes the steps of: (d) aligning the first and second thrusters, respectively, so as to be generally parallel to the yaw axis; (e) positioning the spacecraft to thereby generally align the yaw axis in the direction of desired thrust of the spacecraft as it orbits the earth; (f) simultaneously operating the first and second thrusters to achieve a desired new orbit.
(d) aligning the first and second thrusters, respectively, so as to be generally parallel to the yaw axis;
(e) positioning the spacecraft to thereby generally align the yaw axis in the direction of desired thrust of the spacecraft as it orbits the earth;
(f) simultaneously operating the first and second thrusters to achieve a desired new orbit.
A method as set forth in claim 3 wherein step (c) includes the steps of: (d) positioning the spacecraft to thereby generally align the yaw axis with the center of the earth and the roll axis with the orbit speed of the spacecraft as it orbits the earth; (e) aligning the first and second thrusters, respectively, so as to be generally directed through the center of mass of the spacecraft; (f) operating the first thruster at a predetermined location in the orbit of the spacecraft; (g) operating the second thruster at a location in the orbit of the spacecraft spaced approximately 180Â° around the orbit from the predetermined location; to thereby achieve north-south station keeping of the spacecraft.
wherein step (c) includes the steps of: (d) positioning the spacecraft to thereby generally align the yaw axis with the center of the earth and the roll axis with the orbit speed of the spacecraft as it orbits the earth; (e) aligning the first and second thrusters, respectively, so as to be generally directed through the center of mass of the spacecraft; (f) operating the first thruster at a predetermined location in the orbit of the spacecraft; (g) operating the second thruster at a location in the orbit of the spacecraft spaced approximately 180Â° around the orbit from the predetermined location; to thereby achieve north-south station keeping of the spacecraft.
(d) positioning the spacecraft to thereby generally align the yaw axis with the center of the earth and the roll axis with the orbit speed of the spacecraft as it orbits the earth;
(e) aligning the first and second thrusters, respectively, so as to be generally directed through the center of mass of the spacecraft;
(f) operating the first thruster at a predetermined location in the orbit of the spacecraft;
(g) operating the second thruster at a location in the orbit of the spacecraft spaced approximately 180Â° around the orbit from the predetermined location;
to thereby achieve north-south station keeping of the spacecraft.
A method as set forth in claim 5 wherein the three-axis stabilized spacecraft includes a plurality of momentum wheels operable for storing angular momentum and stabilizing the attitude of the spacecraft; and wherein step (g) further includes: reducing the stored angular momentum of the momentum wheels by aligning the second thruster such that its thrust vector does not pass through the center of mass of the spacecraft.
wherein the three-axis stabilized spacecraft includes a plurality of momentum wheels operable for storing angular momentum and stabilizing the attitude of the spacecraft; and
wherein step (g) further includes: reducing the stored angular momentum of the momentum wheels by aligning the second thruster such that its thrust vector does not pass through the center of mass of the spacecraft.
reducing the stored angular momentum of the momentum wheels by aligning the second thruster such that its thrust vector does not pass through the center of mass of the spacecraft.
A method as set forth in claim 3 wherein the three-axis stabilized spacecraft includes momentum wheels for controlling the orientation thereof, and wherein the plurality of operations includes at least one of the following steps of: (d) thrusting along the yaw axis to assist in reaching a geosynchronous orbit; (e) reducing the stored angular momentum of the momentum wheels; and (f) north-south stationkeeping of the spacecraft.
wherein the plurality of operations includes at least one of the following steps of: (d) thrusting along the yaw axis to assist in reaching a geosynchronous orbit; (e) reducing the stored angular momentum of the momentum wheels; and (f) north-south stationkeeping of the spacecraft.
(d) thrusting along the yaw axis to assist in reaching a geosynchronous orbit;
(e) reducing the stored angular momentum of the momentum wheels; and
(f) north-south stationkeeping of the spacecraft.
A thruster device attached to a spacecraft having a north face which when on station in orbit about the earth said north face generally faces north and a south face which when on station in orbit about the earth, said south face generally faces south, said thruster device comprising: a thruster having a thrust vector; a thermal radiator having a generally planar surface attached to and having thermal contact with said thruster, the thrust vector of said thruster being generally parallel to the planar surface of said thermal radiator; a support means for mounting said thruster and said thermal radiator adjacent said north face, said thruster and said radiator being positioned a spaced distance in a direction normal to the north face and a spaced distance in a direction tangential to the north face away from the geometric center of the north face; and gimbal means pivotally mounting said thruster and said thermal radiator on said support means for selectively positioning the thrust vector of said thruster.
a thruster having a thrust vector;
a thermal radiator having a generally planar surface attached to and having thermal contact with said thruster, the thrust vector of said thruster being generally parallel to the planar surface of said thermal radiator;
a support means for mounting said thruster and said thermal radiator adjacent said north face, said thruster and said radiator being positioned a spaced distance in a direction normal to the north face and a spaced distance in a direction tangential to the north face away from the geometric center of the north face; and
gimbal means pivotally mounting said thruster and said thermal radiator on said support means for selectively positioning the thrust vector of said thruster.
A device as set forth in claim 8 wherein said generally planar surface of said thermal radiator is generally parallel to one of said north face and said south face.
wherein said generally planar surface of said thermal radiator is generally parallel to one of said north face and said south face.
A device as set forth in claim 8 wherein the thrust vector of said thruster is generally directed through the center of mass of said spacecraft.
wherein the thrust vector of said thruster is generally directed through the center of mass of said spacecraft.
A device as set forth in claim 8 further comprising: a second thruster attached to and having thermal contact with said planar surface of said thermal radiator, said second thruster having a second thrust vector.
a second thruster attached to and having thermal contact with said planar surface of said thermal radiator, said second thruster having a second thrust vector.
A device as set forth in claim 11 wherein the second thrust vector of the second thruster is directed through the center of mass of said spacecraft.
wherein the second thrust vector of the second thruster is directed through the center of mass of said spacecraft.
A device as set forth in claim 11 wherein the sum of the first and second thrust vectors lies generally in a plane parallel to one of said north face and said south face of said spacecraft.
wherein the sum of the first and second thrust vectors lies generally in a plane parallel to one of said north face and said south face of said spacecraft.
A thruster device attached to a spacecraft having a south face which when on station in orbit about the earth said south face generally faces south, said thruster device comprising: a thruster having a thrust vector; a thermal radiator having a generally planar surface attached to and having thermal contact with said thruster, the thrust vector of said thruster being generally parallel to the planar surface of said thermal radiator; a support means for mounting said thruster and said thermal radiator adjacent the south face, said thruster and said thermal radiator being positioned a spaced distance in a direction normal to the south face and a spaced distance in a direction tangential to the south face away from the geometric center of the south face; and gimbal means pivotally mounting said thruster and said thermal radiator on said support means for selectively positioning the thrust vector of said thruster.
a support means for mounting said thruster and said thermal radiator adjacent the south face, said thruster and said thermal radiator being positioned a spaced distance in a direction normal to the south face and a spaced distance in a direction tangential to the south face away from the geometric center of the south face; and
A system for performing at least one operation of a three-axis stabilized spacecraft having roll, pitch, and yaw axes, and having a north face and a south face which when on station in orbit about the earth generally face north and south, respectively, said system comprising: first and second thrusters having first and second thrust vectors, respectively; first support means for mounting said first thruster adjacent said north face, said first thruster being positioned a spaced distance away from said north face in a first direction parallel to the pitch axis and a spaced distance away from the pitch axis in a second direction normal to the pitch axis; second support means for mounting said second thruster adjacent said south face, said second thruster being positioned a spaced distance away from said south face in a third direction opposite the first direction and a spaced distance away from the pitch axis in the second direction; and gimbal means pivotally mounting said first and second thrusters on said first and second support means, respectively, for selectively positioning the thrust vectors of said first and second thrusters, said gimbal means including: a first gimbal for mounting each of said first and second thrusters for pivotal movement about an axis parallel to the roll axis between a stowed inoperative position to a position at which the first and second thrust vectors are directed away from the pitch axis.
gimbal means pivotally mounting said first and second thrusters on said first and second support means, respectively, for selectively positioning the thrust vectors of said first and second thrusters, said gimbal means including: a first gimbal for mounting each of said first and second thrusters for pivotal movement about an axis parallel to the roll axis between a stowed inoperative position to a position at which the first and second thrust vectors are directed away from the pitch axis.
a first gimbal for mounting each of said first and second thrusters for pivotal movement about an axis parallel to the roll axis between a stowed inoperative position to a position at which the first and second thrust vectors are directed away from the pitch axis.
A system for performing at least one of a plurality of operations including
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