Patent Application
20140122046
The present disclosure generally relates to spacecraft proximity operations, and more particularly relates to methods and systems for emulating spacecraft proximity operations in a laboratory.
Laboratories have been developed that enable hardware-in-the-loop simulations of proximity operations performed by spacecraft. For example, the laboratories include a test bed that includes a chaser spacecraft and a target spacecraft simulator that float via air pads on a flat floor. Sensors and actuators of the chaser spacecraft may be tested relative to the target spacecraft. Such a laboratory requires a large space to operate and is expensive to implement.
As a result, it is desirable to provide improved methods and systems for emulating spacecraft proximity operations in a laboratory. Other desirable features and characteristics will become apparent from the subsequent detailed description and the appended claims, taken in conjunction with the accompanying drawings and this background of the invention.
According to various exemplary embodiments, systems and methods are described for emulating spacecraft proximity operations. In one embodiment, a method includes: projecting an image of a first spacecraft on a surface and initiating a proximity operation between the first spacecraft and a second spacecraft. The method further includes evaluating sensor feedback from the second spacecraft based on the proximity operation.
In another exemplary embodiment, a system includes a projection device that projects an image of a first spacecraft on a surface. The system further includes a hardware prototype of a second spacecraft. The system further includes a test module that initiates a proximity operation between the first spacecraft and the second spacecraft.
Other embodiments, features and details are set forth in additional detail below.
The present invention will hereinafter be described in conjunction with the following figures, wherein like numerals denote like elements, and
The following detailed description of the invention is merely exemplary in nature and is not intended to limit the invention or the application and uses of the invention. Furthermore, there is no intention to be bound by any theory presented in the preceding background or the following detailed description. As used herein, the term “module” refers to any hardware, software, firmware, electronic control component, processing logic, and/or processor device, individually or in any combination, including, without limitation: an application specific integrated circuit (ASIC), an electronic circuit, a processor (shared, dedicated, or group) and memory that executes one or more software or firmware programs, a combinational logic circuit, and/or other suitable components that provide the described functionality.
Turning now to the figures and with initial reference to
The exemplary emulation system 12 is shown to include at least two spacecraft 14, 16. The first spacecraft 14 is a projected image of all or part of hardware components of a space vehicle. As can be appreciated, the space vehicle may be any vehicle that is designed to fly in space for example, for the purpose of, communications, earth observation, meteorology, navigation, planetary exploration, and transportation.
In various embodiments, a projector 18 is located in some relation to a surface 20 of the laboratory 10. The projector 18 projects the image of the first spacecraft 14 on the surface 20. The projector 18 includes a projector module 22 that includes or communicates with software such as Satellite Tool Kit (STK) or other software to project the image on the surface 20. The software projects the first spacecraft 14 such that the first spacecraft may be rotated and translated to perform proximity operations.
The second spacecraft 16 is a hardware prototype of a space vehicle. As can be appreciated, the space vehicle may be a hardware prototype of any vehicle that is designed to fly in space, for example, for the purpose of communications, earth observation, meteorology, navigation, planetary exploration, and transportation.
In various embodiments, the second spacecraft 16 is a surrogate spacecraft, or testbed, which can maneuver in three rotational degrees of freedom in the laboratory. As shown, the testbed is supported by a spherical airbearing 24 that may be mounted on a cement or other type of block 26. The testbed is rotatable about xyz axes via the airbearing 24.
The testbed includes any or all of the subsystems that are typically associated with a spacecraft, including but not limited to, attitude control (ACS), a momentum control system (MCS) to torque the vehicle, power, thermal, telemetry and command, structure, and a payload. In general, the testbed includes one or more actuators A1-An, and one or more sensors S1-Sn for managing spacecraft momentum and torque needs for attitude control. The testbed further includes one or more control modules 28 that control the operations of the spacecraft 16 and report a system state. The control module 28 includes embedded software for processing external commands, implementation of control/steering laws and implementation of internal housekeeping, and fault management functions.
The emulation system 12 utilizes the two spacecraft 14, 16 to emulate and test proximity operations, such as, but not limited to docking of the two spacecraft 14, 16. To emulate and test the spacecraft 14, 16, the emulation system 12 includes one or more test modules 30. The test module 30 communicates with the projector module 22, and/or the control module 28. The test module 30 can be located on the second spacecraft 16 (as shown), can be located remote from the second spacecraft 16 (e.g., in another room (not shown) separate from the laboratory 10), or located in part on the second spacecraft 16 and located in part remote from the second spacecraft 16 (e.g., as two or more modules that communicate).
The test module 30 issues commands to the projector 18 and the second spacecraft 16, and evaluates feedback from the second spacecraft 16. The test module 30 emulates and tests the various proximity operations by setting the origin of the second spacecraft 16 as an unmoving reference and evaluating the first spacecraft 14 as it translates and rotates with respect to the second spacecraft 16. By evaluating the two spacecraft 14, and 16 in this manner, the sensors S1-Sn of the second spacecraft 16 are able to sense the same images as in actual proximity operations with an actual first spacecraft.
Referring now to
The method may begin at 100. The first spacecraft 14 is projected on the surface 20 of the laboratory 10 at 110. A test of a proximity operation is initiated by the test module 16 at 120. Based on the proximity operation, one or more commands are generated by the test module 30 to the control module 28 of second spacecraft 16 and to the projector module 22 of the projector 18 at 130. The actuators A1-An and/or the sensors S1-Sn of the second spacecraft 16 are controlled by the control module 28 based on the commands at 140. Substantially simultaneously or thereafter, projection of the first spacecraft 14 is controlled by the projector module 22 based on the commands at 150. The test module 30 collects and evaluates feedback from the control module 28 and/or the sensors S1-Sn based on the proximity operation at 160. Test results are then generated based on the evaluation at 170. Thereafter, the method may be repeated and/or may end at 180.
As can be appreciated, one or more aspects of the present disclosure can be included in an article of manufacture (e.g., one or more computer program products) having, for instance, computer usable media. The media has embodied therein, for instance, computer readable program code means for providing and facilitating the capabilities of the present disclosure. The article of manufacture can be included as a part of a computer system or provided separately.
Additionally, at least one program storage device readable by a machine, tangibly embodying at least one program of instructions executable by the machine to perform the capabilities of the present disclosure can be provided.
While at least one example embodiment has been presented in the foregoing detailed description of the invention, it should be appreciated that a vast number of equivalent variations exist. It should also be appreciated that the embodiments described above are only examples, and are not intended to limit the scope, applicability, or configuration of the invention in any way. Rather, the foregoing detailed description will provide those skilled in the art with a convenient road map for implementing various examples of the invention. It should be understood that various changes may be made in the function and arrangement of elements described in an example embodiment without departing from the scope of the invention as set forth in the appended claims and their legal equivalents.
