Systems and methods for immobilizing with change of impedance
An apparatus produces contractions in skeletal muscles of a target to impede locomotion by an animal or human target. The apparatus is used with at least one electrode for conducting a current through the target. The apparatus may be implemented as an electronic disabling device. The apparatus includes two circuits. The first circuit includes a transformer and a first capacitor. The second circuit includes a second capacitor and a secondary winding of the transformer. The second circuit is a series circuit with the electrode. In operation with the electrode, the transformer impresses a voltage on the electrode of greater magnitude than the first voltage, and the current is responsive to discharge of the first capacitor and discharge of the second capacitor.
1. An apparatus for producing contractions in skeletal muscles of a target, the apparatus for use with at least one provided electrode, the apparatus comprising:
a supply of energy;
a first circuit that couples the supply to the electrode for beginning conducting the current through the target, the first circuit having a first output impedance; and
a second circuit that couples the supply to the electrode for continuing conducting the current through the target, the second circuit having a second output impedance less than the first output impedance; wherein
the first circuit supplies a first maximum absolute value of the current;
the second circuit supplies a second maximum absolute value of the current less than the first maximum absolute value; and
the current via the electrode through the target comprises five or more pulses per second to produce contractions in skeletal muscles of the target to impede locomotion by the target.
2. The apparatus of claim 1 wherein the first circuit comprises a switch.
3. The apparatus of claim 2 wherein the switch conducts for beginning conducting the current.
4. The apparatus of claim 3 wherein the supply comprises a capacitance and the switch conducts in response to charging of the capacitance.
5. The apparatus of claim 1 wherein:
the apparatus further comprises a transformer that couples the supply to the electrode, the transformer comprising a primary winding and a secondary winding;
the first circuit comprises the primary winding; and
the second circuit comprises the secondary winding.
6. The apparatus of claim 5 wherein the transformer has a winding ratio for voltage step up.
7. The apparatus of claim 1 wherein the supply comprises a capacitance and the current is responsive to discharging the capacitance.
8. The apparatus of claim 1 wherein:
the supply comprises a first capacitance and a second capacitance;
when conducting the current begins, the first capacitance has a first voltage absolute magnitude across the first capacitance;
when conducting the current begins, the second capacitance has a second voltage absolute magnitude across the second capacitance; and
the first voltage absolute magnitude substantially differs in magnitude from the second voltage magnitude.
9. The apparatus of claim 8 wherein the first voltage absolute magnitude is less than the second voltage absolute magnitude.
10. The apparatus of claim 1 wherein:
the supply comprises a first capacitance and a second capacitance; and
the first circuit couples at least the first capacitance to the target and the second circuit couples at least the second capacitance to the target.
11. The apparatus of claim 1 wherein the second circuit couples energy from the supply to the target after a gap between the electrode and the target begins conducting the current.
12. The apparatus of claim 11 wherein operation of the first circuit causes the gap to begin conducting the current.
13. The apparatus of claim 1 further comprising the electrode and a second electrode, the electrode and the second electrode for conducting the current through the target.
14. The apparatus of claim 1 wherein:
the first circuit couples a first capacitance of the supply to the target to discharge the first capacitance during a first period;
the second circuit couples a second capacitance of the supply to the target to discharge the second capacitance during a second period; and
the second period overlaps the first period to continue the current through the target.
15. A method for disabling a target, the method for use with at least one provided electrode, the method comprising:
sourcing electricity via the electrode at a first voltage to ionize an air gap at the target thereby enabling a first current through the target; and
sourcing electricity via the electrode at a second voltage less in absolute magnitude than the first voltage thereby enabling a second current through the target, the second current comprising five or more pulses per second for producing contractions in skeletal muscles of the target to impede locomotion by the target, wherein a first maximum absolute value of the first current is greater than a second maximum absolute value of the second current.
16. A method for disabling a target, the method for use with at least one provided electrode, the method comprising:
providing from a first stored energy device a first signal to the target via the electrode to ionize an air gap at the target; and
providing from a second stored energy device a second signal to the target via the electrode to continue a current through the gap and through the target, the current for producing contractions in skeletal muscles of the target to impede locomotion by the target, wherein a maximum energy of the first signal is greater than a maximum energy of the second signal.
17. The method of claim 16 wherein:
the first stored energy device has a first voltage just before providing the first signal;
the second stored energy device has a second voltage just before providing the second signal; and
the first voltage is less in absolute magnitude than the second voltage.
18. The method of claim 16 wherein:
the first stored energy device has a first stored energy just before providing the first signal;
the second stored energy device has a second stored energy just before providing the second signal; and
the second stored energy is less than the first stored energy.
19. A device for disabling a target, the device for use with at least one provided electrode, the device comprising:
means for providing from a first stored energy device a first signal to the target via the electrode to ionize an air gap at the target; and
means for providing from a second stored energy device a second signal to the target via the electrode to continue a current through the gap and through the target, the current comprising five or more pulses per second for producing contractions in skeletal muscles of the target to impede locomotion by the target, wherein a maximum energy of the first signal is greater than a maximum energy of the second signal.
20. The device of claim 19 wherein:
the first stored energy device has a first voltage just before providing the first signal;
the second stored energy device has a second voltage just before providing the second signal; and
the first voltage is less in absolute magnitude than the second voltage.
21. The device of claim 19 wherein:
the first stored energy device has a first stored energy just before providing the first signal;
the second stored energy device has a second stored energy just before providing the second signal; and
the second stored energy is less than the first stored energy.