Self-locating compass
Systems, methods, and apparatuses for a self-locating compass for use in navigation are disclosed. The self-locating compass is operable to provide position and/or velocity without information from a global positioning system (GPS) device. The self-locating compass includes a direction finder and a Lorentz force detector. The method includes determining orientation with respect to Earth's magnetic field, measuring a Lorentz force proportional to rate of change of location with respect to the field, determining a change in location, and updating location.
1. A device for measuring velocity comprising:
at least one sensing unit, wherein the at least one sensing unit comprises a first loop and a second loop; and
an energy source operable to provide a bias current;
wherein the first loop comprises a sensing element connected at a first end and a second end to the energy source, wherein the sensing element is operable to carry the bias current;
wherein the second loop comprises a first conductor connected between a first side of the sensing element and a measurement circuit;
wherein the measurement circuit is further connected to a second conductor connected to a second side of the sensing element;
wherein the second loop is operable to determine a potential based on deflection of the bias current by a drag force; and
wherein a magnetic velocity is calculated based on the potential.
2. The device of claim 1 , wherein the measurement circuit comprises a connection to an amplifier, wherein the amplifier is further connected to an analog-to-digital (A/D) converter, wherein the A/D converter is further connected to the output of the measurement circuit.
3. The device of claim 1 , wherein the second loop is at least one of an optoelectronic type or an inductive type.
4. The device of claim 1 , wherein the sensing element is formed from a material having a slow charge relaxation rate.
5. The device of claim 1 , wherein the sensing element has a length to width ratio greater than 1:1.
6. The device of claim 1 , wherein the first conductor and the second conductor are formed of a fast-relaxing material.
7. The device of claim 1 , wherein the measurement circuit includes a temperature compensation unit.
8. The device of claim 1 , wherein the sensing element comprises a source type connection to the energy source and sink type connections at the first end and the second end.
9. The device of claim 1 , wherein the at least one sensing unit comprises a plurality of sensing units, wherein at least two sensing units of the plurality of sensing units are in a non-parallel arrangement.
10. A device for measuring velocity comprising:
at least one sensing unit, wherein the at least one sensing unit comprises a first loop and a second loop; and
wherein the first loop comprises a sensing element operable to carry a bias current from an energy source;
wherein the second loop comprises a first conductor connected between a first side of the sensing element and a measurement circuit;
wherein the measurement circuit is further connected to a second conductor connected to the second side of the sensing element;
wherein the second loop is operable to determine a potential based on deflection of the bias current by a drag force; and
wherein the potential is used to calculate a velocity.
11. The device of claim 10 , wherein the first conductor and the second conductor are formed of a fast-relaxing material.
12. The device of claim 10 , wherein the measurement circuit comprises an input connected to an amplifier, wherein the amplifier is further connected to an analog-to-digital (A/D) converter, wherein the A/D converter is further connected to the output of the measurement circuit.
13. The device of claim 10 , wherein the second loop is of an optoelectronic type.
14. The device of claim 10 , wherein the sensing element is formed from a material having a slow charge relaxation rate.
15. A method of determining velocity comprising:
a power source providing a bias current in a sensing element of at least one sensing unit, wherein the at least one sensing unit comprises a first loop and a second loop;
detecting and measuring deflection of the bias current by a drag force;
determining a potential based on the deflection; and
calculating a magnetic velocity using the potential;
wherein the second loop comprises a first conductor connected between a first side of the sensing element and a measurement circuit; and
wherein the measurement circuit is further connected to a second conductor connected to a second side of the sensing element.
16. The method of claim 15 , wherein the measuring of the deflection comprises amplifying the potential to provide an amplified signal, converting the amplified signal to a digital signal, and providing the digital signal to a processor for processing to provide the calculated magnetic velocity.
17. The method of claim 15 , further including adjusting an orientation of the sensing element with respect to the magnetic field to alter coupling to the magnetic field.
18. The method of claim 15 , further including adjusting the bias current to provide desirable magnitude of the deflection.
19. The method of claim 15 , further including converting the magnetic velocity to velocity-over-ground by normalizing the magnetic velocity for local field strength to form a normalized magnetic velocity and projecting the normalized magnetic velocity on a horizontal.
20. The method of claim 15 , wherein the calculating of the magnetic velocity comprises temperature compensation.