This application claims priority to Indian Provisional Patent Application No. 202011003908, filed Jan. 29, 2020, the entire content of which is incorporated by reference herein.
The present invention generally relates to electromagnetic machines, such as spherical motors, and more particularly relates to electromagnetic machines with payload attachment assemblies.
In recent years, unmanned autonomous vehicle (UAV), robotic, and surveillance camera industries have grown relatively quickly. Many devices within these industries rely on DC motors effectuate various motions. In the context of UAVs that include a camera, actuators are used to move the camera, in two degrees-of-freedom, to a specific position and to remain stable in that position when the UAV is moving. Currently, motion in each degree-of-freedom is implemented using a separate DC motor.
Various attempts have been made to develop electromagnetic machines (e.g., motors/actuators) that can rotate in multiple degrees-of-freedom. The electromagnetic machines heretofore developed suffer certain drawbacks. For example, the machines can be relatively large and relatively expensive to manufacture, and can be relatively complex.
Hence, there is a need for multi-degree-of-freedom machine that is relatively small and inexpensive, as compared to known designs, and that can independently or synchronously generate torque and/or rotate along two perpendicular axes. The present invention addresses at least this need.
This summary is provided to describe select concepts in a simplified form that are further described in the Detailed Description. This summary is not intended to identify key or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.
In one embodiment, a multi-degree-of-freedom electromagnetic machine includes a spherical stator, a first coil, a second coil, a third coil, an armature, a payload mount assembly, and a payload. The spherical stator has a first axis of symmetry, a second axis of symmetry, and a third axis of symmetry. The first, second, and third axes of symmetry are disposed perpendicular to each other. The first coil is wound on the spherical stator about the first axis of symmetry, the second coil is wound on the spherical stator about the second axis of symmetry, and the third coil is wound on the spherical stator about the third axis of symmetry. The armature is spaced apart from, and surrounds at least a portion of, the spherical stator, and is mounted for rotation about the first axis of symmetry and second axis of symmetry. The payload mount assembly is coupled to the armature and to the spherical stator. The payload is spaced apart from the spherical stator and the armature and is coupled to the payload mount assembly. The payload is mounted to rotate, relative to at least a portion of the payload mount assembly, about a payload rotational axis that is parallel to the first axis of symmetry and perpendicular to the second axis of symmetry. The payload is disposed such that its center of gravity is at a position where the second axis of symmetry and the payload rotational axis intersect. The armature is rotatable relative to at least a portion of the payload mount assembly about the first axis of symmetry, and the armature and payload mount assembly are rotatable relative to the spherical stator about the second axis of symmetry. When the armature rotates about the first axis of symmetry, the payload simultaneously rotates about the payload rotational axis, and when the armature rotates about the second axis of symmetry, the payload mount assembly and the payload simultaneously rotate about the second axis of symmetry.
In another embodiment, a multi-degree-of-freedom electromagnetic machine includes a spherical stator, a first coil, a second coil, a third coil, an armature, a payload mount assembly, a bracket arm, a first pulley, a second pulley, a belt and a payload. The spherical stator has a first axis of symmetry, a second axis of symmetry, and a third axis of symmetry. The first, second, and third axes of symmetry are disposed perpendicular to each other. The first coil is wound on the spherical stator about the first axis of symmetry, the second coil is wound on the spherical stator about the second axis of symmetry, and the third coil is wound on the spherical stator about the third axis of symmetry. The armature is spaced apart from, and surrounds at least a portion of, the spherical stator, and is mounted for rotation about the first axis of symmetry and second axis of symmetry. The bracket arm is coupled to the spherical stator and to the armature. The first pulley is rotationally mounted on the bracket arm and is coupled to the armature. The first pulley is rotatable, relative to the bracket arm, about the first axis of symmetry. The second pulley is spaced apart from the first pulley and is rotationally mounted on the bracket arm. The second pulley is rotatable, relative to the bracket arm, about a payload rotational axis that is parallel to the first axis of symmetry and is perpendicular to the second axis of symmetry. The belt is mounted on the first and second pulleys to transfer torque from the first pulley to the second pulley, whereby rotation of the first pulley about the first axis of symmetry causes rotation of the second pulley and the payload about the payload rotational axis. The payload is coupled to the second pulley and is rotatable therewith about the payload rotational axis. The payload is disposed such that its center of gravity is at a position where the second axis of symmetry and the payload rotational axis intersect. The armature is rotatable relative to the bracket arm about the first axis of symmetry, and the armature and bracket arm are rotatable relative to the spherical stator about the second axis of symmetry. When the armature rotates about the first axis of symmetry, the payload simultaneously rotates about the payload rotational axis, and when the armature rotates about the second axis of symmetry, the bracket arm and the payload simultaneously rotate about the second axis of symmetry.
In yet another embodiment, a multi-degree-of-freedom electromagnetic machine includes a spherical stator, a first coil, a second coil, a third coil, an armature, a lever arm, and a payload. The spherical stator has a first axis of symmetry, a second axis of symmetry, and a third axis of symmetry. The first, second, and third axes of symmetry are disposed perpendicular to each other. The first coil is wound on the spherical stator about the first axis of symmetry, the second coil is wound on the spherical stator about the second axis of symmetry, and the third coil is wound on the spherical stator about the third axis of symmetry. The armature is spaced apart from, and surrounds at least a portion of, the spherical stator, and is mounted for rotation about the first axis of symmetry and second axis of symmetry. The lever arm is rotationally coupled to the armature. The payload is spaced apart from the spherical stator and the armature and is rotationally coupled to the lever arm. The payload is mounted to rotate about a payload rotational axis that is parallel to the first axis of symmetry and perpendicular to the second axis of symmetry. The payload is disposed such that its center of gravity is at a position where the second axis of symmetry and the payload rotational axis intersect. The armature is rotatable relative to the payload mount assembly about the first axis of symmetry, and the armature and lever arm are rotatable relative to the spherical stator about the second axis of symmetry. When the armature rotates about the first axis of symmetry, the payload simultaneously rotates about the payload rotational axis, and when the armature rotates about the second axis of symmetry, the lever arm and the payload simultaneously rotate about the second axis of symmetry.
Furthermore, other desirable features and characteristics of the multi-degree-of-freedom electromagnetic machine will become apparent from the subsequent detailed description and the appended claims, taken in conjunction with the accompanying drawings and the preceding background.
The present invention will hereinafter be described in conjunction with the following drawing figures, wherein like numerals denote like elements, and wherein:
The following detailed description is merely exemplary in nature and is not intended to limit the invention or the application and uses of the invention. As used herein, the word “exemplary” means “serving as an example, instance, or illustration.” Thus, any embodiment described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other embodiments. All of the embodiments described herein are exemplary embodiments provided to enable persons skilled in the art to make or use the invention and not to limit the scope of the invention which is defined by the claims. Furthermore, there is no intention to be bound by any expressed or implied theory presented in the preceding technical field, background, brief summary, or the following detailed description.
Referring now to
As
Returning now to
Regardless of the shape and dimensions, however, the magnets 306 are preferably arranged such that the polarity of the first and second magnets 306-1, 306-2 relative to the spherical stator 102 is opposite to the polarity of the third and fourth magnets 306-3, 306-4. For example, in the embodiment depicted in
The payload mount assembly 106 is coupled to the spherical stator 102, the armature 104, and to the payload 108. The payload 108, which is spaced apart from the spherical stator 102 and the armature 104, is mounted to rotate, relative to at least a portion of the payload mount assembly 106, about a payload rotational axis 112. As
Regardless of the specific type of payload 108, the payload mount assembly 106 is configured such that the armature 104 is rotatable relative to the payload mount assembly 106 about the first axis of symmetry 110-1, and the armature 104 and payload mount assembly 106 are rotatable relative to the spherical stator 102 about the second axis of symmetry 110-2. The payload mount assembly 106 is also configured such that when the armature 104 rotates about the first axis of symmetry 110-1, the payload 108 simultaneously rotates about the payload rotational axis 112, and when the armature 104 rotates about the second axis of symmetry 110-2, the payload mount assembly 106 and the payload 108 simultaneously rotate about the second axis of symmetry 110-2.
It will be appreciated that the payload mount assembly 106 may be variously implemented to provide the above-described functionality. Some specific implementations are depicted in
Referring first to
The first pulley 404 is rotationally mounted on the bracket arm 402 and is coupled to the armature 104. The first pulley 404 is rotatable, relative to the bracket arm 402, about the first axis of symmetry 110-1. The second pulley 406 is spaced apart from the first pulley 404 and is also rotationally mounted on the bracket arm 402. The second pulley 406 is, however, coupled to the payload 108 and is rotatable, relative to the bracket arm 402, about the payload rotational axis 112. In the depicted embodiment, a shaft 414 is coupled between the second pulley 406 and the payload 108. As may be appreciated, any one of numerous types of suitable non-illustrated hardware may be used to rotationally mount the first pulley 404 and the second pulley 406 on the bracket arm 402.
The belt 408 is mounted on the first and second pulleys 404, 406 and transfers torque from the first pulley 404 to the second pulley 406. As a result, when the armature 104 rotates about the first axis of symmetry 110-1, it imparts a torque to the first pulley 404 causing it to also rotate about the first axis of symmetry 110-1. The first pulley 404, via the belt 408, imparts a torque to the second pulley 406 causing it, and concomitantly the payload 108, to rotate about the payload rotational axis 112.
As
Turning now to
The lever arm 804 is rotationally coupled, via suitable mounting hardware 812, to the armature 104, and is also rotationally coupled, via suitable mounting hardware 814, to the payload 108. Although the shape of the lever arm 804 may vary, it is, at least in the depicted embodiment, non-linearly shaped. The shape may be chosen, as may be appreciated, to effectuate a desired range of motion.
In the depicted embodiment, and as shown more clearly in
In yet another embodiment, which is depicted in
The first support arm 1304-1 is non-rotationally coupled, via suitable mounting hardware, to the frame 1302 and is rotationally coupled, via a first bearing 1402-1 (see
The frame 1302 is rotationally coupled to the armature 104, via suitable mounting hardware, in a manner that allows the armature 104 to rotate, relative to the frame 1302, about the first axis of symmetry 110-1. With this configuration, when the armature 104 is caused to rotate about the second rotational axis 110-2, the payload mount assembly 106 (e.g., frame 1302, first arm 1304-1, second arm 1304-2, and lever arm 804), and thus the payload 108, also rotate about the second rotational axis 110-2. Moreover, and similar to previously described embodiment, the lever arm 804 is shaped such that when the armature 104 is rotated through 60-degrees of rotation about the first axis of symmetry 110-1 (e.g., from a reference position to 45-degrees in one rotational direction and to 15-degrees in the opposite rotational direction), the payload is rotated through 120-degrees of rotation about the payload rotational axis 112.
In this document, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Numerical ordinals such as “first,” “second,” “third,” etc. simply denote different singles of a plurality and do not imply any order or sequence unless specifically defined by the claim language. The sequence of the text in any of the claims does not imply that process steps must be performed in a temporal or logical order according to such sequence unless it is specifically defined by the language of the claim. The process steps may be interchanged in any order without departing from the scope of the invention as long as such an interchange does not contradict the claim language and is not logically nonsensical.
Furthermore, depending on the context, words such as “connect” or “coupled to” used in describing a relationship between different elements do not imply that a direct physical connection must be made between these elements. For example, two elements may be connected to each other physically, electronically, logically, or in any other manner, through one or more additional elements.
While at least one exemplary embodiment has been presented in the foregoing detailed description of the invention, it should be appreciated that a vast number of variations exist. It should also be appreciated that the exemplary embodiment or exemplary embodiments 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 an exemplary embodiment of the invention. It being understood that various changes may be made in the function and arrangement of elements described in an exemplary embodiment without departing from the scope of the invention as set forth in the appended claims.
Number | Date | Country | Kind |
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202011003908 | Jan 2020 | IN | national |