HUBLESS SPIN MOTOR-BASED CONTROL MOMENT GYROSCOPES

Abstract

ABSTRACT Hubless spin motor-based control moment gyroscope provides full three-axis attitude control for small satellites using compact control moment gyroscopes based on hubless spin Motors, arranged in a pyramidal configuration within the satellite. The present invention comprises an a hubless spin motor, a flywheel, a gimbal (nutation) motor, a slip ring, an encoder, and essential mechanical supporting components. The said flywheel is directly attached to the hubless spin motor’s rotor, generating angular momentum in both clockwise and counterclockwise directions. The slip ring and encoder are integrated with the gimbal motor in the center of the hubless spin motor, facilitating power transfer and measuring the gimbal angle, respectively. The said Hubless spin motor-based Control Moment Gyroscope is integrated into limited spaces without sacrificing performance, achieved by optimizing the shapes and mounting positions of each component.

Specification

Description:FIELD OF INVENTION
The present invention relates to satellites. Specifically, the present invention relates to control moment gyroscope. More particularly, the present invention relates to spin motor based on hubless spin motor-based control moment gyroscope.
BACKGROUND OF THE INVENTION
Generally, the control moment gyroscope (CMG) refers to a motor-driven apparatus equipped with a flywheel with a high moment of inertia. It is used to generate torques for position stabilization and re-orientation of various platforms, including satellites, ships, submarines, automobiles, aircraft, missiles, and more, to achieve the desired objectives.
With reference to figure 1, A control moment gyroscope (CMG) is a torque-generating actuator that operates on gyroscopic principles. It includes components such as a flywheel B1, a spin motor B2, and a gimbal motor B3, which are arranged perpendicularly to each other. Specifically, the flywheel is mounted on the rotating axis of the spin motor, and the rotating axis of the gimbal motor is positioned perpendicularly to the spin motor's axis. When the spin motor rotates the flywheel at high speeds, momentum is generated. By rotating the spin motor's axis B4 about the gimbal motor's axis, torque (T) B5 is produced on an axis perpendicular to these two shafts. However, conventional CMGs, as described, often occupy considerable space due to their large volume and the need for a second stator in a hollow spin motor. Given the limited storage capacity of satellites, the size and mass of the CMG must be minimized as much as possible. The large volume of traditional CMGs makes them less suitable for small satellite applications.
During the past decade, there has been growing interest within the space industry in developing small satellites. These small satellites are typically categorized as nanosats (1-10 kg), microsats (10-100 kg), or minisats (100-500 kg) and range in size from softballs to refrigerators. The interest in these satellites is driven by the current constraints of traditional satellites and launch systems. Consequently, there has been a significant effort to reduce satellite size and mass, enabling small satellites to complement larger satellites. Examples of such missions include imaging, remote sensing, surveillance, disaster management, and blue force tracking. These missions require payloads with precise pointing capabilities, necessitating an attitude control system (ACS) equipped with small control moment gyroscopes that can fit within the volume and mass constraints of small satellites.
Traditional satellites are typically associated with budgets in the millions or billions of dollars and development schedules spanning several years. The failure of such satellites is extremely costly, which leads to the reliance on space-proven, often outdated technologies, leaving very little room for innovation. Enormous amounts of money and effort are expended on the development of redundant systems and the maintenance of outdated techniques and procedures. Consequently, the development of traditional satellites has historically been limited to countries with large military and/or commercial budgets.
Small satellites offer an alternative. Advances in technology have enabled small satellites to perform many of the tasks of their larger predecessors at a fraction of the cost and time required for traditional space satellites. As a result, risk aversion is reduced, and small satellite developers are more willing to explore new, unproven technologies that may lead to lower mission costs and/or increased functionality of the satellite. It should be noted that the willingness of small satellite developers to explore new technologies and innovative designs is a key factor in their success.
Various control moment gyroscope has been devised in art; some of the measures are as follows:
US 9199746 relates to Attitude Control System for Small Satellites that include an attitude control system for use with small satellites. According to various embodiments, the system allows rapid retargeting (e.g., high slew rates) and full three-axis attitude control of small satellites using a compact actuation system. In certain embodiments, the compact actuation system includes a plurality of single-gimbaled control moment gyroscopes (SGCMG) arranged in a pyramidal configuration that are disposed within a small satellite.
US 10139226 relates to Control Moment Gyroscope which can be provided in a limited space since the volume thereof can be reduced without change in performance by optimizing the shapes and mounting positions of each component. To this end, the control moment gyroscope of the present invention is a control moment gyroscope for generating torque in the orthogonal directions to both of two shafts which are perpendicularly disposed to each other by rotating the two shafts , and the control moment gyroscope comprises : a gimbal motor formed in a hollow cylinder shape and supplying momentum ; spin motor provided inside the gimbal motor and supplying momentum in a perpendicular direction to the momentum of the gimbal motor; and a flywheel provided in the inside of the gimbal motor and supplied with the rotational force of the gimbal motor and the rotational force of the spin motor
US 9354079 relates to Control Moment Gyroscopes including Torsionally-stiff Spoked Rotors and methods for manufacture thereof of the present invention as are embodiments of a method for fabricating CMGs. In one embodiment, a CMG includes a stator housing, an inner gimbal assembly (IGA), and a torque motor coupled to the stator housing and configured to rotate the IGA about a gimbal axis to selectively generate a desired output torque during operation of the CMG. The IGA includes, in turn, an IGA Support structure rotatably coupled to the stator housing a monolithic CMG rotor rotatably mounted to the IGA support structure, and a spin motor coupled to the IGA support structure and configured to rotate the monolithic CMG rotor about a spin axis.
US 8052093 relates to Control Moment Gyro and Device for Assembly Thereof that includes an inertial wheel mounted, via a wheel Support, on the moving part or rotor of a cardan assembly. The cardan assembly is provided with a stator and the rotor is rotatable with respect to the stator about a first axis of rotation, it being possible for the spinner of the inertial wheel to be set in rotation about a second axis of rotation not aligned with the first axis of rotation. The stator of the cardan is mounted on a block and fixed to this block via an arrangement of vibration attenuators or insulators. The mechanism for setting the rotor in rotation is at least partially housed in the interior volume of the block.
US8312782 discloses control moment gyroscope-based momentum control systems in small satellites. The design centers around a traditional CMG system for spacecraft attitude control with multiple Control Moment Assemblies (CMAs) mounted orthogonally or in parallel to manage the spacecraft's orientation. Each CMA includes a momentum rotor, spin motor, gimbal motor, and associated bearings, with a focus on generating and controlling torque via spinning rotors and gimbal adjustments.
A known Indian patent application 202341059496 discloses control moment gyroscope for attitude control of satellites and free-flying robots. It discloses Uses a conventional flywheel design with a central flywheel motor rotor that is externally integrated with magnets around the outer radius, while the flywheel motor stator is positioned in the inner radius. The flywheel is attached to a motor drive card that rotates along with the flywheel, enhancing angular momentum and optimizing the rotor mass ratio. Focuses on balancing the center of gravity of the flywheel assembly for precise angular momentum pointing.
The present invention relates to hubless flywheel for generating angular momentum, eliminating the traditional central hub. This provides a lighter and more compact design. - The focus is strictly on maintaining and adjusting angular momentum with a entralized nutation motor to control the gimbal's orientation, rather than a setup involving multiple CMAs. The system lacks a sealed enclosure, simplifying the structure compared to the hermetically sealed designs in the other patent.

OBJECT OF THE INVENTION:
The main object of the present invention is to provide a hubless spin motor-based control moment gyroscopes.
It is one object of the present invention, wherein the said hubless spin motor-based control moment gyroscopes is a compact system for small satellite to control attitude.
It is one object of the present invention, wherein the said hubless spin motor-based control moment gyroscopes are arranged in a pyramidal configuration to provide full three-axis attitude control for small satellites.
It is yet another object of the present invention, wherein the said hubless spin motor-based control moment gyroscopes includes a hubless spin motor, a nutation motor, an encoder, a slip ring, a flywheel, and supporting structures.
It is yet another objection of the present invention, wherein a plurality of single hubless motor-based control moment gyroscopes with stand arranged in a pyramidal configuration with respect to one another.
It is another object of the present invention, wherein the angular momentum generated by the flywheel can be increased by increasing the width of the flywheel without changing the inner and outer diameters, thereby not altering the volume of the HM-CMG.
It is another object of the present invention, wherein the flywheel made of metal such as aluminum, stainless steel, mild steel, etc. to increase the inertia of the flywheel with justifiable tradeoff in the increase of mass.
It is one object of the present invention, wherein HM-CMG design offers exceptional compactness and a superior torque-to-volume ratio by fitting the gimbal motor inside the Hubless spin motor, compared to traditional CMGs.
It is another object of the present invention, wherein when four HM-CMGs operate together in a pyramid configuration, they efficiently generate angular momentum in a perpendicular direction to the gimbal motor, enabling precise satellite orientation in space.
SUMMARY
The main aspect of the present invention is to provide an hubless spin motor-based control moment gyroscope comprises; Hubless flywheel attached directly with rotor, rotor with magnets connected with outer race of the thin section bearing; stator base with stator teeth is covered by armature windings, nutation motor rotating shaft is connected with Nutation Motor Support to provide structure integrity for the nutation, slip Ring is connected with slip ring support rod; slip ring support rod is connected with nutation motor support, Encoder is placed between nutation motor and the shaft from the stator base to measure the angular position of the hubless spin motor; thin section Ball Bearing's inner race is connected with stator, ball bearing are placed in left side and right side support, left side adaptor left side and right side adaptors are connected in the stator base, stand is attached to slip ring support rod and ball bearing in the left side adaptor.
It is one aspect of the present invention, wherein permanent magnets are placed at an interval circumferentially along the surface of the rotor.
It is one aspect of the present invention, wherein the nutation motor is position at the center of the hubless spin motor, with its shaft attached to the left side adaptor 11 to gimbal the hubless spin motor
It is one aspect of the present invention, wherein the nutation motor is placed in the center of the hubless motor and is rigidly supported by the nutation motor support and the slip ring rod connected to the stand.
It is one another aspect of the present invention, wherein rod from the slip ring pass through the right-side adaptor with a ball bearing, providing rotational movement and structural support for the hubless motor around the longitude axis of the nutation motor.
It is one aspect of the present invention, wherein the slip ring used in this system is a hollow model with a hallow passage.
It is one aspect of the present invention, wherein the encoder used is a hollow-through encoder, allowing the nutation motor shaft to pass through and connect with the left-side adapter.
It is one aspect of the present invention, wherein the hubless spin motor is rotated by a nutation motor along with the left and right-side adaptors.
It is one aspect of the present invention, wherein the left and right-side adaptors are connected with ball bearings to provide rotational support for the hubless spin motor and to distribute angular momentum and load to the satellite through the stand.
BRIEF DESCRIPTION OF DRAWINGS
Figure 1 illustrates a basic diagram of a control Moment Gyroscopes, according to the present invention.
Figure 2 illustrates a basic diagram of a pyramid configurations of control moment Gyroscopes, according to the present invention.
Figure 3 illustrates a basic diagram of a Flywheel, according to the present invention.
Figure 4 illustrates a perspective view for description of single Hubless Motor-Control Moment Gyroscope (HM-CMG), according to the present invention.
Figure 5 illustrates a bottom view for description of single Hubless Motor-Control Moment Gyroscope (HM-CMG), according to the present invention.
Figure 6 illustrates a cut view for description of single Hubless Motor-Control Moment Gyroscope (HM-CMG, according to the present invention.
Figure 7 illustrates exploded perspective of view for description of single Hubless Motor-Control Moment Gyroscope (HM-CMG), according to the present invention.
Figure 8 illustrates a perspective view for description of single Hubless Motor-Control Moment Gyroscope (HM-CMG) with stand, according to the present invention.
Figure 9 illustrates a side view for description of single Hubless Motor-Control Moment Gyroscope (HM-CMG) with stand, according to the present invention.
Figure 10 illustrates a perspective view for description of 4 Hubless Motor-Control Moment Gyroscopes (HM-CMG) with stands assembled in Pyramid configuration, according to the present invention.

DETAILED DESCRIPTION OF INVENTION WITH REFERENCE TO ACCOMPANYING DRAWINGS:
With reference to figures 2-3, the present invention relates to hubless spin motor-based control moment gyroscopes (HM-CMG). The said hubless spin motor-based control moment gyroscopes (HM-CMGs) are arranged in a pyramidal configuration to provide full three-axis attitude control for small satellites.
In this embodiment, the HM-CMG includes a hubless spin motor, a nutation (gimbal) motor, an encoder, a slip ring, a flywheel, and supporting structures. The hubless spin motor is an outer rotor motor with the rotor positioned outside the stator. It may be a brushless DC (BLDC) motor comprising a stator base/teeth, windings, and a rotor with magnets, or a coreless brushless DC motor without stator teeth, having only windings in the stator base and a rotor with magnets. The flywheel, which is directly attached to the rotor of the hubless spin motor, is a thick metal disc designed to generate angular momentum by rotating at high speeds along with the rotor. The inner and outer diameters of the flywheel disc are determined by the rotor's dimensions, while the disc's height can be adjusted to meet specific angular momentum requirements based on the following formula.
The moment generated by the inertial actuator has the following expression:
M_H=2I_r ψ ̇θ ̇
I_r Hubless flywheel inertial moment
ψ ̇ Spin speed
θ ̇ Gimbal speed
The inertial moment of the hubless flywheel, denoted as I_r and the hubless flywheel's velocity of rotation around its axis (spin), denoted as ψ, along with the gimbal velocity, denoted as θ ̇, are related by the following equations. Here I_r represents the inertia of the flywheel, which functions as a hubless cylinder.
I_r=m_r ((r_1^2 + r_2^2)/2)
And m_r=ρπ(r_1^2- r_2^2 )e
Where m_r is the mass of the hubless flywheel, ρ is density of the disc, r1 (exterior radius), r2 (interior radius) and e is the height of the hubless cylinder. The angular momentum of the hubless cylinder can increase by increased by increasing the height e of the hubless flywheel. This, in turn, increases the mass m_r and inertial moment I_r of the hubless flywheel.
Wirh reference to figure 9, The flywheel is designed to maximize the capacity of angular momentum storage while considering effects of size, mass, and vibrations. The flywheel may be made of metal such as stainless steel to increase the inertia of the flywheel with justifiable tradeoff in the increase of mass. The flywheel may be an axisymmetric rotor which is designed to have maximum inertia about its axis of rotation within its mass and volume constraints
The stator base with teeth is electromagnetically energized, as the electric currents are cylindrical structure, the structural integrity and the stability applied to the corresponding coils. Although not illustrated, the rotor may include a plurality of permanent magnets provided on a surface facing the plurality of cores mentioned above. Accordingly, under the influence of repulsive or attractive force between the corresponding magnets and the corresponding electromagnetically energized cores between the gap, the rotor and the flywheel to be described below are rotated.
The hubless spin motor can be driven by a microcontroller in two different ways-one by using the Hall effect sensor feedback to determine the position of the rotor and the second by using back EMF (electromotive force) generated by the coils as feedback to control the speed of the hubless spin motor. The second method requires three electrical connections to run the motor as against eight required by the first. The number of electrical connections to the hubless spin motor must be limited as all these connections must be routed through the slip ring to allow endless rotation of the flywheel assembly.
The thin section bearings in the hubless spin motor assembly support the integrated flywheel with rotor and motor stator. The bearings should be able to rotate at a continuous speed, such as about 8000 rpm, through the lifetime of the HM-CGM. For example, hybrid bearings with silicon nitride balls (ceramic) and steel races may be chosen for this application. A hybrid ceramic bearing is a combination of ceramic rolling elements with steel bearing races. The ceramic balls provide a chemically inert surface at the ball-race contact. The HM-CMG is not isolated from the rest of the satellite components; the bearings in the HM-CMG are expected to run with marginal or no lubrication to prevent outgassing and contamination (due to debris from lubricant) of electronic equipment in the satellite. The hybrid bearings are chosen as they can operate without lubrication for a longer time and have lower coefficient of thermal expansion and lower coefficient of friction compared to steel bearings.
The nutation motor is placed at the center of the hubless spin motor, with its shaft attached with stator base of the hubless spin motor by an adapter. This setup allows the nutation motor to rotate at the gimbal velocity θ ̇, directing the angular momentum in the desired direction. The nutation motor can be a brushless DC motor with or without gears, a stepper motor, or a servo motor.
A high-resolution encoder is mounted between the nutation motor and the shaft from the stator base to measure the angular position of the hubless spin motor. The encoder can either be a hollow shaft or an encapsulated type. In this invention, a hollow shaft encoder is used to measure the gimbal angular position, allowing the shaft from the hubless spin motor to pass through the encoder and connect with the nutation motor shaft.
The opposite end of the nutation motor is attached to a rigid structural component that holds the nutation motor firmly in place when torque and angular momentum are generated to control or turn the satellite. This rigid gimbal structure is secured to the satellite body by a rod passing through a bearing and adapter connected to the hubless spin motor. When the nutation motor rotates the hubless spin motor, the adapter will rotate as well, while the bearing attached to the adapter will prevent the rotation of the nutation motor and supporting structural parts.
Power and signals for the hubless spin motor are delivered through a low-friction slip ring attached to the nutation motor at the center of the hubless spin motor. The slip ring comprises two parts: a rotating part and a stationary part. The rotating part is connected to the hubless spin motor. As the nutation motor rotates the hubless spin motor, the rotating part of the slip ring maintains contact with the stationary part, ensuring continuous power transfer through the connected wires. The slip ring can be hollow, pancake-shaped, or capsule-shaped. In this invention, a hollow slip ring is used, allowing the rigid gimbal structure to pass through the center of the slip ring.
There are two bearings in the HM-CMG assembly, one on each side of the HM-CMG. This placement ensures equal distribution of launch loads on the two bearings. The radial and axial clearances are designed considering the thermal expansion effects and are kept to a minimum to avoid axial and radial movements of the HM-CMG that can affect the satellite dynamics.

Arrangement of the present invention:
With reference to figures 4-10, the flywheel 1 is directly attached to the rotor 2 to generate inertia by rotating the rotor 2 at high RPM. The rotor 2 is rotated by the stator core 3, which is energized by coil windings through the supply of electricity, creating repulsive or attractive forces between the magnets in the rotor 2 and the stator 3. The rotor 2, with the attached flywheel 1, can rotate in both clockwise and counterclockwise directions to change the direction of inertia. The stator 3 may include stator teeth with coil windings around the teeth, or it may be coreless, featuring only coils in the stator 3 to reduce weight. This design exhibits low rotational inertia, thereby enabling quicker acceleration and deceleration.
In one embodiment of the present invention, both the rotor 2 and stator 3 are connected by the thin section bearing 9 to allow the flywheel 1 to spin seamlessly. The thin section bearing 9 can be a hybrid model, where the balls are made from ceramic materials and the inner and outer races are made from high-grade steel to reduce friction and operate without lubrication in space. Alternatively, it can be a full ceramic ball bearing, with both the inner and outer races also made from ceramic materials. Using a thin section bearing without lubrication avoids outgassing, meaning that the lubricant in the ball bearing does not vaporize to unacceptable levels in a vacuum condition. The said thin section bearings in the hubless spin motor assembly support the rotation movement of flywheel with rotor and maintaining the air gap between stator and rotor.
In another embodiment of the present invention, wherein both the left 11 and right 12 side adaptors are connected at the bottom of the stator base 3 to provide structural support, transferring the load and inertia to the satellite through bearings 10. The inertia generated by flywheel 1 is directed by the shaft of nutation motor 4, which is connected to the left adaptor 11, allowing the flywheel to gimbal in the required direction to control the satellite's attitude. The left 11 and right 12 side adaptors rotate along with the hubless motor, driven by nutation motor 4. The ball bearings 10 on right side attached in the right-side adaptor 12 keep the nutation motor 4, nutation motor support 5, and slip ring support 7 stationary in the center. And the ball bearing 10 on left side attached in the left side adaptor 11 keeping the whole invention stead, connected with satellite and transferring the angular moment. The ball bearing 10 on both sides allows the flywheel 1 the flywheel 1 rotates around the stationary components: nutation motor 4, encoder 8, slip ring 6, nutation motor support 5, and slip ring support 7. This setup ensures that the rotational forces and momentum are effectively managed and directed for precise satellite attitude control.
The nutation motor 4 is connected to the nutation motor support 5 and the slip ring support 7. A rod from the slip ring support 7 passes through the bearing 10 attached to the right-side adaptor 12 and is connected to the stand 13. The nutation motor support 5 and slip ring support 7 provide structural support for the nutation motor 4, encoder 8, & slip ring 6, and transfer the load to stand 13. Finally, the load transfer from the stand 13 to the satellite. This configuration ensures stable and efficient transmission of rotational forces and loads, enabling precise control of the satellite's attitude.
In another embodiment of the present invention, the electrical current for the stator core 3 is supplied through a slip ring 6, where the rotating part of the slip ring 6 maintains continuous contact with the stationary part. In this system, the outer part of the slip ring 6 rotates while the inner part remains stationary and connected with slip ring support 7. The slip ring 6 used is a hollow model with a passage through its center. A support rod from the slip ring support 7 passes through this hollow center, providing a pathway for structural integrity and ensuring the stable transfer of electrical current to the stator core 3 while allowing the necessary rotational movement for the system's operation.
In yet another embodiment of the present invention, an encoder 8 is used to measure the gimbal angle of the hubless spin motor's position, providing precise feedback for accurate control. The encoder 8 employed in this system is a hollow-through encoder 8, which allows the nutation motor 4 shaft to pass through its center. This design enables the shaft to connect seamlessly with the left-side adapter 11. By integrating the hollow-through encoder 8, the system ensures that the angular position of the nutation motor 4 is accurately monitored, facilitating precise adjustments required for small satellite applications while enhancing the overall control and reliability of the system.
In even another embodiment of the present invention, the rod from the slip ring support 7 and the bearing 10 on the left side are connected to the stand 13, providing structural support for the nutation motor 4, slip ring 6, and encoder 8. This configuration ensures that these components are securely positioned at the center of the hubless motor. The system efficiently transfers inertia, angular momentum, and torque from the HM-CMG to the satellite with precision accuracy, allowing for precise attitude control. The stand 13 is L-shaped to position the HM-CMG 14 at an angle of approximately 45 to 55 degrees relative to the longitudinal axis of each HM-CMG 14, providing optimal freedom for satellite attitude control. This arrangement ensures the system's compactness and effectiveness in small satellite applications, enhancing overall control and reliability.
In yet another embodiment of the present invention, a plurality of single hubless motor-based control moment gyroscopes (HM-CMGs) 14 are arranged in a pyramidal configuration with respect to one another. Each HM-CMG 14, mounted on an L-shaped stand 13, is positioned at an optimal angle to maximize its effectiveness in contributing to the overall system's performance. This pyramidal arrangement allows the combined system of HM-CMGs 14 to work in unison, providing comprehensive three-axis attitude control of the satellite. By leveraging the precise and responsive nature of the hubless motors, the system ensures accurate and reliable orientation control. This configuration not only enhances the satellite's stability and maneuverability but also optimizes the space utilization within the satellite, making it highly efficient for small satellite applications. The careful placement and coordination of each HM-CMG 14 in the pyramid ensure that the generated torques and angular momenta are effectively combined, resulting in a robust attitude control system capable of meeting the stringent requirements of modern satellite missions.
The angular momentum generated by the flywheel 1 can be increased by augmenting the width of the flywheel without changing its inner and outer diameters. This design choice ensures that the overall volume of the hubless motor-based control moment gyroscope (HM-CMG) 14 remains constant, preserving the compactness of the system. The flywheel 1 is constructed from metals such as aluminum, stainless steel, or mild steel, selected for their ability to provide a significant increase in inertia with a justifiable trade off in the increase of mass. By using these materials, the flywheel 1 achieves a higher angular momentum, enhancing the overall performance of the HM-CMG 14. This approach allows for a more efficient generation of the necessary forces for satellite attitude control without compromising the spatial constraints critical in small satellite applications. The careful balance between the flywheel's 1 mass and its inertia ensures that the HM-CMG 14 can deliver the required torque and angular momentum while maintaining the system's lightweight and compact characteristics.
Functioning of the invention:
The flywheel rotates along with rotors when the stator core is energized by supplying electrical current, creating repulsive or attractive forces between the corresponding magnets and the electromagnetically energized cores. The electrical current for the stator core is supplied through a slip ring, with the rotating part of the slip ring maintaining contact with the stationary part and the outer part of the slip ring rotates while the inner part remains stationary. The slip ring used in this system is a hollow model with a hallow passage. A slip ring support rod passes through the hollow center of the slip ring. An encoder is used to measure the gimbal angle of the hubless spin motor's position and the said encoder used is a hollow-through encoder, allowing the nutation motor shaft to pass through and connect with the left-side adapter. The hubless spin motor is rotated by a nutation motor along with the left and right-side adaptors. The left and right-side adaptors are connected with ball bearings to provide rotational support for the hubless spin motor and to distribute angular momentum and load to the satellite through the stand. The nutation motor is placed in the center of the hubless motor and is rigidly supported by the nutation motor support and the slip ring rod connected to the stand. The stand is L-shaped to position the HM-CMG at an angle approximately between 45 to 55 degrees relative to the longitudinal axis of each HM-CMG. A plurality of single hubless motor-based control moment gyroscopes (HM-CMGs) with stand arranged in a pyramidal configuration with respect to one another. A pyramidal configuration of 4 HM-CMGs operable to provide three-axis attitude control of the satellite. The angular momentum generated by the flywheel can be increased by increasing the width of the flywheel without changing the inner and outer diameters, thereby not altering the volume of the HM-CMG. The flywheel made of metal such as aluminum, stainless steel, mild steel, etc. to increase the inertia of the flywheel with justifiable tradeoff in the increase of mass.







, Claims:WE CLAIM
1. Hubless spin motor-based control moment gyroscope comprises:
a) Hubless flywheel 1 attached directly with rotor 2;
b) Rotor with magnets 2 connected with outer race of the thin section bearing 9;
c) Permanent magnets are fixed at an interval circumferentially along the surface of the rotor 2
d) Inner race of the thin section bearing 9 is connected with stator 3;
e) Stator base with Stator Teeth 3 is covered by armature windings;
f) Left side 11 and right side 12 adaptors are connected in the stator 3 base;
g) Nutation motor 4 rotating shaft is connected with left side adaptor 11;
h) Encoder 8 is placed between nutation motor 4 and left side adaptor 11 to measure the angular position of the hubless spin motor 1;
i) Nutation motor 4 is connected with Nutation motor support 5;
j) Slip ring support rod 7 is connected with nutation motor support 5;
k) Slip ring 6 is connected with slip ring support rod 7;
l) Ball Bearing 10 are placed in left side 11 and right side 12 adaptors;
m) Slip ring support rod 7 passing through the right side adaptor 12 to connect with Stand 13 with ball bearing 10;
Wherein the nutation motor is fixed at the center of the hubless spin motor with its shaft attached to the left side adaptor to gimbal the hubless spin motor; and
Wherein electrical current for the stator core is supplied through a slip ring, with the rotating part of the slip ring maintaining contact with the stationary part.
2. Gyroscope as claimed in claim 1, wherein the flywheel rotates along with rotors when the attached stator teeth are energized by supplying electrical current, creating repulsive or attractive forces between the corresponding magnets and the electromagnetically energized cores.
3. Gyroscope as claimed in claim 1, wherein the nutation motor is placed in the center of the hubless motor and is rigidly supported by the nutation motor support and the slip ring rod connected to the stand.
4. Gyroscope as claimed in claim 1, wherein rod from the slip ring pass through right-side adaptor with a ball bearing, providing rotational movement and structural support for the hubless motor around the longitude axis of the nutation motor.
5. Gyroscope as claimed in claim 1, wherein the slip ring used in this system is a hollow model with a hallow passage.
6. Gyroscope as claimed in claim 1, wherein the encoder used is a hollow-through encoder, allowing the nutation motor shaft to pass through and connect with the left-side adapter.
7. Gyroscope as claimed in claim 1, wherein the hubless spin motor is rotated by a nutation motor along with the left and right-side adaptors to provide rotational support and to distribute angular momentum and load to the satellite through the stand.
8. Gyroscope as claimed in claim 1, wherein the stand is L-shaped to position the hubless spin motor-based control moment gyroscope at an angle approximately between 45 to 55 degrees relative to the longitudinal axis of each hubless spin motor-based control moment gyroscope.
9. Gyroscope as claimed in claim 1, wherein the angular momentum generated by the flywheel increases by increasing the width of the flywheel without changing the inner and outer diameters, thereby not altering the volume of the hubless spin motor-based control moment gyroscope.
10. Gyroscope as claimed in claim 1, wherein a plurality of single hubless motor-based control moment gyroscopes with stand arranged in a pyramidal configuration of four hubless spin motor-based control moment gyroscopes operable to provide three-axis attitude control of the satellite.

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