Abstract
The present invention discloses systems and methods for electromagnetic spacecraft propulsion or thrust generation without the expulsion of reaction mass. The systems include capacitor assemblies with a switch-controlled conductive discharge path, a means of charging the capacitor assemblies, a means of generating magnetic fields using electromagnetic coils, and a means for periodically shaping the intensity, duration and polarity of magnetic fields from the coils. Thrust is generated through the interaction of the shaped magnetic fields and the segmented current in the conductive discharge path during capacitor discharge.
Claims
1. An electromagnetic thrusting system comprising: capacitor assemblies of two or more charge-carrying conductive elements; one or more conductive discharge elements for each capacitor assembly; one or more electromagnetic coils; a switchable means for periodically charging the capacitor assemblies; a switchable means for periodically discharging the capacitor assemblies; a means for generating currents of desired amplitude, duration, and frequency in the electromagnetic coils; a means for modulating currents in the conductive discharge elements to desired amplitudes, durations, and frequencies; wherein a net unidirectional force is created by the interaction of the magnetic fields generated by the electromagnetic coils and the currents in the conductive discharge elements of the capacitor assemblies.
2. An electromagnetic thrusting system according to claim 1, wherein charge-carrying elements of the capacitor assemblies have opposite polarities.
3. An electromagnetic thrusting system according to claim 1, wherein charge-carrying elements of the capacitor assemblies are comprised of rectangular planar conductors.
4. An electromagnetic thrusting system according to claim 1, wherein charge-carrying elements of the capacitor assemblies are comprised of concentric cylindrical conductors.
5. An electromagnetic thrusting system according to claim 1, wherein charge-carrying elements of the capacitor assemblies are comprised of any unusual geometric configuration.
6. An electromagnetic thrusting system according to claim 1, wherein various system elements may be enclosed in or separated by electromagnetic shielding.
7. An electromagnetic thrusting system according to claim 1, wherein each charge-carrying conductive element of a capacitor assembly may have a dielectric coating of high electric permittivity.
8. An electromagnetic thrusting system according to claim 1, wherein charge-carrying conductive elements of the capacitor assemblies may be periodically connected to a voltage source through mechanical or electronic charging switches.
9. An electromagnetic thrusting system according to claim 1, wherein charge-carrying conductive elements of the capacitor assemblies may be periodically charged, discharged or recharged to desired voltages and polarities.
10. An electromagnetic thrusting system according to claim 1, wherein charge-carrying conductive elements of the capacitor assemblies may be periodically discharged through conductive discharge elements by means of mechanical or electronic discharging switches.
11. An electromagnetic thrusting system according to claim 1, wherein discharge currents in the conductive discharge elements may be modulated by means of resistors, capacitors, inductors, or other electronic means.
12. An electromagnetic thrusting system according to claim 1, wherein the charge-carrying conductive elements of the capacitor assemblies may be engineered so as to control the paths of the discharge currents within the capacitor elements.
13. An electromagnetic thrusting system according to claim 1, wherein the charge-carrying conductive elements of the capacitor assemblies may be geometrically reconfigured by mechanical means.
14. An electromagnetic thrusting system according to claim 1, wherein the electromagnetic coils may or may not have cores of high magnetic permeability.
15. An electromagnetic thrusting system according to claim 1, wherein a controlled current is sent through the electromagnetic coils to generate a shaped magnetic field of desired polarity, intensity and duration.
16. An electromagnetic thrusting system according to claim 1, wherein one or more electromagnetic coils are positioned with axes of symmetry perpendicular to the conductive discharge elements of the capacitor assemblies.
17. An electromagnetic thrusting system according to claim 1, wherein two or more rectangular electromagnetic coils are positioned with some sides perpendicular to and some sides parallel to the charge-carrying elements of a planar capacitor assembly.
18. An electromagnetic thrusting system according to claim 1, comprised of multiple capacitor assemblies and electromagnetic coils arranged linearly, radially or circumferentially about a common axis of symmetry.
19. An electromagnetic thrusting system according to claims 1 and 16, wherein a net unidirectional force on the system may be generated substantially parallel to the axis of symmetry of the system.
20. An electromagnetic thrusting system according to claims 1 and 16, wherein a net unidirectional force on the system may be generated substantially perpendicular to the axis of symmetry of the system.
21. An electromagnetic thrusting system according to claims 1 and 16, wherein a net torque on the system may be generated substantially perpendicular to or parallel to the axis of symmetry of the assembly.
22. An electromagnetic thrusting system according to claims 1 and 16, wherein any combination of net torque and forces on the system may be generated according to claims 17 through 21.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] The accompanying drawings, which are incorporated in and form part of the specification, illustrate various principles of operation and examples of the present invention, including a preferred embodiment of the invention, as well as alternate embodiments, and, together with the detailed description, serve to explain the principles of the invention.
[0021] FIG. 1 is a schematic diagram illustrating the Lorentz force acting on a charged particle moving through a magnetic field;
[0022] FIG. 2 is a schematic diagram illustrating the unbalanced Lorentz force acting on charged particles moving orthogonally in the same plane;
[0023] FIG. 3 is a schematic diagram illustrating the mutual Lorentz forces acting on segments of parallel conductors;
[0024] FIG. 4 is a schematic diagram illustrating the unbalanced force Lorentz force acting on one segment of two orthogonal conductor segments;
[0025] FIG. 5 is a schematic diagram illustrating the Lorentz force on a conductor segment due to a perpendicular magnetic field;
[0026] FIG. 6 is a schematic diagram illustrating the magnetic field distribution induced on a capacitor discharge element by a perpendicular electromagnetic coil;
[0027] FIGS. 7A and 7B are schematic diagrams illustrating charging and discharging of a capacitor assembly;
[0028] FIG. 8 is a schematic diagram illustrating the magnetic field induced on the discharge element of a capacitor assembly by a Helmholtz coil configuration;
[0029] FIG. 9 is a schematic diagram illustrating a planar capacitor assembly with Helmholtz coils for producing longitudinal thrust;
[0030] FIG. 10 is a schematic diagram illustrating a cylindrical capacitor assembly with Helmholtz coils for producing longitudinal thrust;
[0031] FIG. 11 is a schematic diagram illustrating the use of three radial Helmholtz coil-capacitor assemblies to produce an axial thrust and torque;
[0032] FIG. 12 is a schematic diagram illustrating the use of three circumferentially tangent Helmholtz coil-capacitor assemblies to produce an axial thrust and torque;
[0033] FIG. 13 is a schematic diagram illustrating the use of three capacitor assemblies and six perpendicular electromagnets to produce both axial thrust, planar thrust and torque;
[0034] FIGS. 14A and 14B are schematic diagrams illustrating a parallel plate capacitor assembly and rectangular electromagnetic coils used to produce a longitudinal thrust;
[0035] FIG. 15 is a schematic diagram illustrating planar capacitor assemblies inside a toroidal electromagnetic solenoid used to produce an axial thrust;
[0036] FIGS. 16A and 16B are schematic diagrams illustrating the charge-discharge configurations of a capacitor assembly with dielectrics;
[0037] FIG. 17 is a schematic diagram illustrating the use of three capacitor assembly configurations from FIGS. 16A and 16B to produce axial thrust;
[0038] FIG. 18 is a schematic diagram illustrating the use of one embodiment of the present invention to propel a solar-powered spacecraft.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0039] The present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which preferred embodiments of the invention are shown. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Like numbers refer to like elements throughout.
[0040] The basic operating principle of the present invention is illustrated in FIGS. 7A and 7B. In FIG. 7A, a voltage source 18 is connected through closed charge switches 14 so as to induce opposite charges on capacitor assembly elements 32 and 33. Discharge switches 16 are open, and electromagnetic coil 15 is not energized. In FIG. 7B, the voltage source 18 is disconnected by opening charge switches 14 so as to isolate the charges on capacitor assembly elements 32 and 33. Electromagnetic coil 15 is energized to produce the perpendicular magnetic field components 6 on discharge element 31 in the direction of field vector 2. Discharge switches 16 are then closed, and a current is produced in discharge element 31 as the capacitor discharges. The interaction of the magnetic field 6 with the current in discharge element 31 results in an unbalanced Lorentz force on the system because the electric circuit is not continuous. When elements 32, 33 are sufficiently discharged, the process is repeated.
[0041] With reference to FIG. 8, a refinement of the basic embodiment from FIGS. 7A and 7B is illustrated wherein two electromagnetic coils 15 are positioned in a Helmholtz coil configuration. This produces a stronger and more uniform magnetic field distribution 6 acting as shown on discharge element 31 during capacitor discharge.
[0042] With reference to FIGS. 9 and 10, two of the many geometric possibilities for capacitor assembly design are illustrated based on the capacitor assembly configuration shown in FIG. 6 for the production of an unbalanced Lorentz force. FIG. 9 illustrates two oppositely charged elements of a capacitor assembly 32, 33 consisting of two parallel rectangular plates with a conductive discharge element 31 between them. Each plate may have a dielectric coating. The discharge element 31 is shown located at one end of the capacitor assembly, but may be located anywhere between the two plates 32 and 33. A Helmholtz electromagnetic coil pair 15 is positioned in the required manner such that the axis of symmetry of the coil is perpendicular to the discharge conductor 31. Similarly, FIG. 10 illustrates a capacitor assembly 32, 33 consisting of two concentric cylinders with a conductive discharge element 31 between them. Each cylinder may have a dielectric coating. The discharge element 31 is shown located at one end of the capacitor assembly in such a manner as to maximize the length of element 31. A Helmholtz electromagnetic coil pair 15 is positioned in the required manner such that the axis of symmetry of the coil is perpendicular to the discharge conductor 31.
[0043] With reference to FIG. 11, a preferred embodiment of the present invention is shown in cross-section. In this preferred embodiment, three capacitor assemblies consisting of charge-carrying elements 32, 33 each with a discharge element 31 are positioned radially about an axis of symmetry. Each capacitor assembly has an associated Helmholtz electromagnetic coil pair. Although not shown in FIG. 11, it is understood that each capacitor assembly has connection to a voltage source as well as charge switches 14 and discharge switches 16 as shown in FIGS. 7A and 7B. As with the previous basic capacitor assembly embodiments, the total system forces and moments may be shown to be proportional to the product of the current durations and amplitudes in discharge conductors 31, the total number of turns in electromagnetic coils 15, the relative magnetic permeability of cores in coils 15, the applied voltage across charge-carrying elements 32 and 33, and the usual physics factors for magnetic field strengths. By stacking complete assemblies of the embodiment in FIG. 11 along the axis of symmetry, a single power source can be used to charge all capacitors and energize all electromagnetic coils, while the total uniaxial force will be increased in proportion to the number of assemblies in the stack.
[0044] With reference to FIG. 12, a simple design modification to the embodiment FIG. 11 may be produced by arranging the discharge elements 31 along radials from the system axis of symmetry, and then placing the Helmholtz coils tangentially. This configuration has the advantage of being more compact than the embodiment of FIG. 11.
[0045] With reference to FIG. 13, another preferred embodiment of the present invention includes a plurality of conducting coils 15 arranged about the axis of symmetry of a capacitor assembly system. The coils are arranged so that they may induce perpendicular Lorentz force components on each discharge element 31 both radially and axially with respect to the entire assembly. Appropriate variation of currents in the coils 15 result in both axial and radial translation forces as well as torques on the system, which may be used to produce controlled rotation, axial translation and lateral translation of the system.
[0046] With reference to FIGS. 14A and 14B, another unusual embodiment of the present invention is shown. FIG. 14A contains a capacitor assembly comprised of the usual elements 31, 32, and 33. Elements 7 show the current flow in 33 during discharge. The same current flows from element 33 downward through elements 31 and then into element 32. The current direction in 32 is just the opposite of that in 33. Two rectangular electromagnetic coils 25, 26 are positioned above and below the capacitor assembly. Current applied in 25 produces field 21 in the plane of element 33, and a current in 26 produces field 22 in the plane of element 32. The interaction of currents 7 in 32, 33 with fields 21, 22 produce an unbalanced vertical Lorentz force on the system. FIG. 14B illustrates a configuration consisting of a radial arrangement of multiple assemblies as shown in FIG. 14A to produce a force along the axis of symmetry of the configuration.
[0047] With reference to FIG. 15, another interesting embodiment of the present invention is shown in partial cross-section. An electromagnetic coil 15 is wound about the entire assembly in a toroidal solenoid configuration, which when energized generates a uniform circumferential magnetic field inside the toroid. By way of illustration, four capacitor assemblies (the design may include any number) consisting of elements 31, 32, and 33 are equally spaced inside the toroid, one of which is shown in the cutaway at the top of the figure. Charge switches 14 and discharge switches 16 are shown in open and closed positions respectively. When discharge switches 16 are closed after charging elements 32, 33, a discharge current flows through each element 31, which are aligned radially. The internal toroidal magnetic field interacts with the discharge current to produce a Lorentz force parallel to the axis of symmetry of the coil.
[0048] With reference to FIGS. 16A and 16B, an interesting embodiment of the present invention is shown which can utilize a low voltage for charging the capacitor assembly and then significantly increase the capacitor assembly voltage prior to discharge. The capacitor assembly consists of the usual charge-carrying elements 32, 33 but with each one having a dielectric surface 40. Initially, the capacitor elements 32, 33 are configured such that their respective dielectrics are touching as shown in FIG. 16A. Each element 32, 33 is charged in the usual manner by connecting voltage source 18 through charge switches 14, while electromagnetic coil 15 remains unenergized and discharge switches 16 are configured as an open circuit.
[0049] With reference to FIG. 16B, once elements 32, 33 are charged to the appropriate potential, element 32 is displaced from element 33, by a mechanical means not shown, thereby opening one charging switch 14 and disconnecting voltage source 18. At the point where the displacement of element 32 is such that both displacement switches 16 are closed, so as to complete the discharge circuit as shown, then electromagnetic coil 15 is energized to create field 2, which interacts with the discharge current in 31 to create a Lorentz force normal to the plane of the figures. The interesting fact about this embodiment is that the voltage potential between elements 32, 33 increases as follows due to the separation of the capacitor elements. Assume that the initial displacement of elements 32, 33 in FIG. 16A is h, which is just the total thickness of the dielectric coatings, that the voltage potential of element 18 is V.sub.0, and that the dielectric has a relative electric permittivity value k. If the maximum displacement of 32, 33 as shown in FIG. 16B is H, then the voltage potential between the two charge-carrying capacitor elements increases to kHV.sub.0/h. By way of example, if the dielectric is titanium dioxide with a k value of 100, and if the ratio H/h is 10, the voltage potential between elements 32, 33 at maximum displacement is 1000 times the original charging voltage V.sub.0.
[0050] With reference to FIG. 17, three of the assemblies 32, 33, 40 of FIG. 16 are arranged radially in a circular configuration. Voltage source 18 and charge switches 16 are not shown for clarity but are understood to be required for a functional device. The charge, expand, and discharge process is controlled using a design from radial aircraft engines, consisting of connecting rods 35, crank plate 38, and offset crank pin 37. As pin 37 is rotated around the axis of symmetry 36 of the design, plates 32 move up and down radially. The capacitor assembly 32, 33, 40 is charged when element 32 is closest to 33, and discharged when 32 is at the maximum distance from 33. During discharge, the appropriate coil 15 is energized to interact with the discharge current in element 31, to produce an axial Lorentz force component.
[0051] A practical application of the present invention is illustrated in FIG. 18, which is a schematic of a geosynchronous orbit (GEO) space vehicle. The vehicle includes a satellite 45 as payload, attached by truss structure 44 to four solar panels 42 and two propulsion units 41. Each propulsion unit is a large scale version of the cylindrical capacitor assembly embodiment illustrated in FIG. 8, with the necessary electromagnetic coils and switches to connect and disconnect the propulsion units to the solar panel electrical power system. Compared to a conventional fuel-oxidizer GEO propulsion system, the advantages of using the present invention in this manner are obvious, such as: the lack of large fuel tanks and propellant for a one-time boost to GEO, the lack of station-keeping cold gas thrusters which eventually run out of propellant, the ability to continuously change orbits, and the ability to return to low earth orbit for servicing and then return to GEO without refueling.
[0052] It is to be understood that even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and function of the invention, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.
