US-12618507-B2 - Gimbal stabilisation system

US12618507B2US 12618507 B2US12618507 B2US 12618507B2US-12618507-B2

Abstract

Methods, apparatus, and systems are provided for controlling a payload of a gimbal stabilisation system for an aircraft during testing an antenna under test (AUT). The gimbal stabilisation system including a payload control assembly coupled via a yaw motor to a gimbal assembly. The gimbal assembling including the payload comprising a first section with a transceiver for use in testing the AUT and a second section rotatably coupled to the gimbal assembly. The payload control assembly including a controller configured to operate the yaw motor and gimbal assembly by: receiving an in-flight position of the aircraft during testing of the AUT; receiving a position of the AUT in relation to the aircraft; and controlling the gimbal assembly by: calculating a pointing direction and alignment of the first section of the payload relative to the AUT based on the received position of the aircraft and the received position of the AUT; and maintaining pointing and alignment of the first section of the payload towards the AUT based on the calculated pointing direction and alignment of the first section of the payload.

Inventors

Andrian Buchi
Joakim ESPELAND
Rasmus Kumar Udesen GUPTA

Assignees

QUADSAT APS

Dates

Publication Date: 20260505
Application Date: 20210812
Priority Date: 20200814

Claims (20)

1 . A computer-implemented method of controlling a gimbal stabilisation system of an aircraft in an antenna test system for testing an antenna under test, AUT, the gimbal stabilisation system comprising a control assembly rotatably coupled to a gimbal assembly comprising a payload, the payload comprising a first section including a communication sensor interface for use in testing the AUT and a second section rotatably coupled to the gimbal assembly, the control assembly comprising a controller, the method, performed by the controller, further comprising: receiving an in-flight position of the aircraft during testing of the AUT; receiving a position of the AUT in relation to the aircraft; and controlling the gimbal assembly by: calculating a pointing direction and alignment of the first section of the payload relative to the AUT based on the received position of the aircraft and the received position of the AUT; and maintaining pointing and alignment of the first section of the payload towards the AUT based on the calculated pointing direction and alignment of the first section of the payload, wherein maintaining pointing and alignment of the first section of the payload towards the AUT comprises controlling the pointing and the alignment of the payload about at least three axes of rotation, wherein one axis of rotation of said at least three axes of rotation is configured to control said alignment of the payload.
2 . The computer-implemented method of claim 1 , wherein receiving the in-flight position of the aircraft further comprising receiving data representative of global positioning system, GPS, position, heading, altitude and/or attitude of the aircraft.
3 . The computer-implemented method of claim 1 , further comprising receiving the position of the AUT further comprising receiving data representative of information associated with the position of the AUT.
4 . The computer-implemented method of claim 1 , wherein the communication sensor interface further comprises at least one from the group of: a receiver; a transmitter; a transceiver; and/or any other communication interface and/or communication sensor interface configured for testing the AUT.
5 . The computer-implemented method of claim 1 , wherein the control assembly is rotatably coupled to the gimbal assembly by a first motor, the gimbal assembly further comprising: a first rotating arm coupled to the first motor, the first motor configured to rotate the first rotating arm around a first axis of rotation, the first rotating arm coupled to a second motor at an end of the first rotating arm distal to the coupling of the first rotating arm to the first motor; a second rotating arm coupled to the second motor, the second motor configured to rotate the second rotating arm around a second axis of rotation, the second axis of rotation orthogonal to the first axis of rotation, the second rotating arm coupled to a third motor, wherein the third motor is configured to rotate the payload coupled to the third motor at the second section of the payload about a third axis of rotation, wherein the third axis of rotation is different to the second axis of rotation; and the controller of the control assembly electrically connected to the first motor, the second motor and third motor; wherein controlling the gimbal assembly further comprising: maintaining pointing and alignment of the first section of the payload further comprising controlling one or more of the first motor, second motor, and third motors based on the calculated pointing direction and alignment of the first section of the payload towards the AUT.
6 . The computer-implemented method of claim 5 , wherein the first axis of rotation is a yaw axis of rotation in relation to the gimbal assembly, the second axis of rotation is a pitch axis of rotation in relation to the gimbal assembly, and the third axis of rotation is a roll axis of rotation in relation to the gimbal assembly.
7 . The computer-implemented method of claim 5 , wherein the first, second and third motors each comprise at least one from the group of: a gimbal motor; a brushless motor; a brushless gimbal motor; a gimbal drive motor; and/or any suitable motor for use in adjusting and/or maintaining the pointing direction and/or alignment of the first section of payload in the direction of the AUT.
8 . The computer-implemented method of claim 5 , wherein the first, second and third motors corresponding to a yaw motor, pitch motor and roll motor, respectively.
9 . The computer-implemented method of claim 5 , wherein controlling the gimbal assembly further comprising: calculating the theoretical angles for yaw, pitch and roll of the payload in relation to the AUT; calculating drift offsets of the gimbal assembly based on comparing feedback from data representative of current received position of the aircraft and with attitude and heading reference system of the aircraft for correcting drift in the gimbal assembly; and sending angle commands and drift offsets to a gimbal controller for controlling one or more of the first motor, second motor, and third motors based on combining drift offsets with theoretical angles for yaw, pitch and roll.
10 . The computer-implemented method of claim 5 , wherein controlling the gimbal assembly further comprising: when using the payload for testing linear polarized systems, controlling the gimbal assembly to maintain polarisation alignment of the payload communication sensor interface polarisation with the AUT polarisation by: comparing the received in-flight position of the aircraft with the received position of the AUT; calculating a theoretical roll adjustment value for at least adjusting the roll angle of the payload in relation to the AUT based on the comparison for maintaining polarisation alignment; and sending a roll angle command to the roll motor of gimbal assembly.
11 . The computer-implemented method of claim 1 , wherein a base station is located at a geographic position relative to the AUT, the location of the base station defining a reference position for the aircraft during testing of the AUT, and receiving the position of the AUT further comprises: receiving the position of the base station; calculating the position of the AUT based on the geographic position of the AUT relative to the position of the base station.
12 . The computer-implemented method of claim 1 , wherein the payload further comprises a camera located at the first end of the payload, and receiving the position of the AUT further comprising: analysing one or more image(s) from the camera to identify a position of the AUT; and calculating the position of the AUT based on the identified position of the AUT in said one or more analysed images.
13 . The computer-implemented method of claim 12 , wherein: analysing one or more image(s) from the camera to identify a position of the AUT further comprises analysing one or more image(s) from the camera to identify the AUT; and calculating the position of the AUT based on the position of the identified AUT in said one or more analysed images.
14 . The computer-implemented method of claim 12 , wherein a base station is located at a geographic position relative to the AUT, the location of the base station defining a reference position for the aircraft during testing of the AUT, and receiving the position of the AUT further comprises: receiving the position of the base station; calculating the position of the AUT based on the geographic position of the AUT relative to the position of the base station; and wherein: analysing one or more image(s) from the camera to identify a position of the AUT further comprises analysing one or more image(s) from the camera to identify the base station; and calculating the position of the AUT based on the position of the identified base station in said one or more analysed images and based on the geographic position of the AUT relative to the position of the identified base station.
15 . The computer-implemented method of claim 1 , wherein the AUT includes a beacon signal and receiving the position of the AUT further comprising: receiving the beacon signal associated with the AUT; and determining the position of the AUT based on the received beacon signal.
16 . The computer-implemented method of claim 12 , wherein a base station is located at a geographic position relative to the AUT, the location of the base station defining a reference position for the aircraft during testing of the AUT, and receiving the position of the AUT further comprises: receiving the position of the base station; calculating the position of the AUT based on the geographic position of the AUT relative to the position of the base station; and wherein the base station includes a beacon signal and receiving the position of the AUT further comprises: receiving the beacon signal associated with the based station; and determining the position of the AUT based on the received beacon signal from the base station and the geographic position of the AUT relative to the position of the base station.
17 . The computer-implemented method of claim 1 , further comprising maintaining pointing of the first section of the payload towards a designated position in relation to the AUT.
18 . The computer-implemented method of claim 1 , wherein the aircraft is an unmanned aerial vehicle.
19 . A non-transitory computer-readable medium comprising computer code or instructions stored thereon, which when executed on a processor, causes the processor to perform the computer implemented method according to claim 1 .
20 . A gimbal stabilisation system for an aircraft comprising a control assembly rotatably coupled to a gimbal assembly comprising a payload, the control assembly comprising a controller configured to operate the gimbal assembly to maintain pointing of a first section of the payload towards an antenna under test, AUT, with a second section of the payload rotatably coupled to the gimbal assembly, wherein the first section comprises a communication sensor interface for use in testing the AUT, the gimbal assembly further comprising operating the controller of the gimbal stabilisation system based on a computer-implemented method of controlling a gimbal stabilisation system of an aircraft in an antenna test system for testing an antenna under test, AUT, the gimbal stabilisation system comprising a control assembly rotatably coupled to a gimbal assembly comprising a payload, the payload comprising a first section including a communication sensor interface for use in testing the AUT and a second section rotatably coupled to the gimbal assembly, the control assembly comprising a controller, the method, performed by the controller, further comprising: receiving an in-flight position of the aircraft during testing of the AUT; receiving a position of the AUT in relation to the aircraft; and controlling the gimbal assembly by: calculating a pointing direction and alignment of the first section of the payload relative to the AUT based on the received position of the aircraft and the received position of the AUT; and maintaining pointing and alignment of the first section of the payload towards the AUT based on the calculated pointing direction and alignment of the first section of the payload; wherein maintaining pointing and alignment of the first section of the payload towards the AUT comprises controlling the pointing and the alignment of the payload about at least three axes of rotation, wherein one axis of rotation of said at least three axes of rotation is configured to control said alignment of the payload.

Description

CROSS-REFERENCE TO RELATED APPLICATION This is a U.S. National Stage Application, filed under 35 U.S.C. § 371, of International Patent Application Number PCT/EP2021/072560, filed on Aug. 12, 2021, which claims priority to GB Patent Application No. 2012756.9 filed on Aug. 14, 2020, the disclosures of which are incorporated herein by reference in their entireties. The present application relates to a system, apparatus and method for a gimbal stabilisation system of an aircraft such as an unmanned aerial vehicle (UAV) for use in testing an antenna under test (AUT) and applications thereto. BACKGROUND There are solutions for antenna measurements in which the transmitting and/or receiving probe antenna is mounted on an aircraft such as, without limitation, for example an unmanned aerial vehicle (UAV). These systems usually use a fixed mounted probe antenna system and can be used for measurement of broadcast and telecommunication environments. As directional probe antennas on UAVs are usually used for the measurements, the gain will change depending on where the probe antenna is pointed. Although existing technology uses directional probe antennas which are fixed mounted to the structure of the UAV, which when the UAV is moving will not be able to point at the antenna under test and thus the relative gain of the probe antenna will change depending on the UAV roll, pitch and yaw movements. This is a problem when performing relative measurements of the AUT, where it is required to have a constant gain of the probe which is being used to take the measurement as it moves around the AUT. Alternatively, the flight of the UAV needs to be pre-programmed and/or manually adjusted such that the fixed probe antenna is directed towards the AUT. This is difficult to manually maintain during flight of a UAV for accurate measurements by the fixed probe antenna. Furthermore, for linear polarization RF transmission, it is important that the AUT and the probe antenna on the UAV that is being used for the measurements are aligned. This will allow for co-polar and cross-polar measurements of the AUT. However, the UAV will have movement in its attitude such as, for example, pitch, roll and yaw as it flies. These movements and also the flight path may cause misalignment of the probe antenna if the probe antenna is fixed with the structure of the UAV. Again, such alignment is difficult to manually maintain during flight of the UAV for accurate measurements by the fixed probe antenna. There is a desire for a more improved aircraft/UAV antenna probe system that overcomes at least one or more of these disadvantages. The embodiments described below are not limited to implementations which solve any or all of the disadvantages of the known approaches described above. SUMMARY This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to determine the scope of the claimed subject matter; variants and alternative features which facilitate the working of the invention and/or serve to achieve a substantially similar technical effect should be considered as falling into the scope of the invention disclosed herein. The present disclosure provides method(s), apparatus and system(s) for controlling a gimbal structure to ensure a payload coupled to the gimbal structure, when mounted on an aircraft, such as, without limitation, for example, an unmanned aerial vehicle is pointed and/or aligned with an antenna under test (AUT). The payload may be configured and operable to be used during an antenna performance procedure (APE) for testing and/or measuring the performance of the AUT. The pointing and/or alignment of the payload is calculated and adjusted based on received position information such as, without limitation, for example the position/location(s), attitude, heading, and/or speed of the aircraft/gimbal structure and also received position information such as, without limitation for example the position/location(s) of the AUT. From this, adjustments to the gimbal structure are made to adjust/maintain/control the pointing and/or alignment of the payload in the direction of the AUT. For example, for adjusting/controlling and/or maintaining pointing and alignment of a first section of the payload towards the AUT at least during the APE whilst the aircraft is in-flight. Adjusting the payload in this manner ensures an accurate APE test can be performed with the AUT. In a first aspect, the present disclosure provides a computer-implemented method of controlling a gimbal stabilisation system of an aircraft in an antenna test system for testing an antenna under test (AUT), the gimbal stabilisation system comprising a control assembly rotatably coupled to a gimbal assembly comprising a payload, the payload comprising a first section incl