Steerable parachute control system and method
An autonomous guided parachute system for cargo drops that divides the requirements of guidance and soft landing into separate parachutes. Said invention includes a high wing-loaded ram air parachute for guidance, a larger round parachute for soft landing, a harness/container system, flight computer, position sensors and actuation system. The system is dropped from an airplane. A predetermined period of drogue fall ensures a stable position prior to deploying the guidance parachute. The flight controller determines a heading to intersect with an area substantially above the desired target and controls the guidance parachute via pneumatic actuators connected to the parachutes steering lines to fly on that heading. At a minimum altitude prior to the system's impact with the ground the flight computer transitions the system from the fast high performance guidance parachute to a larger landing parachute by releasing the guidance parachute to static line extract and deploy the landing parachute. If the system reaches a position substantially above target area prior to the parachute transition altitude the flight computer controls the system into a spiral dive or other rapid altitude dropping maneuver until the transition altitude is reached. Once transitioned to the landing parachute the system descends for a brief period unguided under the landing parachute until touchdown.
1. A controllable parachute system for controlled guidance and delivery of an air dropped payload, the system comprising:
a steering ram air guidance parachute, connectable to the payload for a first period of time following launch adapted to quickly move the payload after drop to a first altitude substantially overhead a target location;
a second landing parachute connectable to the payload for a second period of time following launch adapted to land the dropped payload from a second altitude substantially said overhead target location to impact at said target location; and
a flight controller responsive to said target location and to said first and second altitudes, for steering the guidance parachute to the first altitude that is a predetermined first distance substantially overhead said target location, for maneuvering the guidance parachute to the second altitude that is a predetermined second distance substantially overhead said target location less than said first distance without substantially departing from being overhead said target location as it descends from the first to the second altitudes during the first period of time and for transitioning to the second landing parachute substantially at said second altitude prior to impact at the target location.
2. The parachute system according to claim 1 , further comprising a drogue connectable to the payload for a third period of time prior to the first period of time.
3. The parachute system according to claim 2 , further comprising a drogue delay timer determining the third period of time.
4. The parachute system according to claim 1 , wherein the flight controller includes:
a GPS receiver providing information about a current location of the payload;
a processor for determining the system's fight vector and desired flight path capable of controlling actuators to steer the guidance parachute and release actuators to initiate a transfer from the guidance parachute to the landing parachute.
5. The parachute system according to claim 4 , wherein the GPS receiver is loaded with an ephemeris of the target location.
6. The parachute system according to claim 4 , wherein the actuators are pneumatically powered.
7. The parachute system according to claim 1 , wherein the guidance parachute is loaded over three pounds per square foot.
8. The parachute system according to claim 1 , wherein the altitude dropping maneuver includes a spiral dive.
9. The parachute system according to claim 1 , wherein the flight controller includes an altimeter for determining an altitude of the payload.
10. The parachute system according to claim 1 , wherein the flight controller includes a transmitter for sending data from the flight controller to a base station.
11. The parachute system according to claim 1 , wherein the flight controller includes a transceiver for transmitting data between the flight controller to a base station.
12. The parachute system according to claim 1 , wherein the payload is an explosive device.
13. The parachute system according to claim 1 , wherein the flight controller stores data relating to operation of the flight controller during flight.
14. A method for air dropping a payload using a multiple parachute system, the multiple parachute system including at least a guidance parachute and a landing parachute and a flight computer controlling steering and parachute transitioning actuators, comprising the steps of:
launching the payload from a delivery aircraft;
deploying the guidance parachute;
controlling the guidance parachute to position the payload to a first altitude substantially overhead of a target location, to position the payload to a second altitude substantially overhead said target location less than the first altitude without substantially departing from being overhead the target location as it is lowered from the first to the second altitudes; and
deploying the landing parachute substantially at the second altitude prior to impact.
15. The method for air dropping a payload according to claim 14 , further comprising the step of stabilizing the system and cargo under a drogue after launching the payload and prior to deploying the guidance parachute.
16. The method for air dropping a payload according to claim 15 , further comprising the step of using a hydraulic timing mechanism to control the drogue fall time.
17. The method for air dropping a payload according to claim 15 , wherein the step of stabilizing the system and cargo occurs for a predetermined period of time.
18. The method for air dropping a payload according to claim 14 , further comprising the step of releasing tie downs holding the parachute system to the payload to suspend the payload from the parachute system.
19. The method for air dropping a payload according to claim 18 , wherein the step of releasing the tie downs includes releasing the tie downs with tension from a bridal on the drogue.
20. The method of air dropping a payload according to claim 14 , wherein the step of steering the guidance parachute includes the steps of:
determining a current location of the payload;
determining a direction from the current location of the payload to the target location; and controlling the guidance parachute for flight in the determined direction.
21. The method of air dropping a payload according to claim 20 , wherein the step of determining a current location of the payload includes obtaining a position location from a GPS receiver.
22. The method of air dropping a payload according to claim 21 , further comprising the step of loading an ephemeris for the target location in the GPS receiver prior to the launching step.
23. The method of air dropping a payload according to claim 14 , further comprising the steps of:
determining flight data relating to flight of the parachute system and payload; and
storing the flight data.
24. The method of air dropping a payload according to claim 14 , further comprising the steps of: determining flight data relating to flight of the parachute system and payload; and
transmitting the flight data to a base station.
25. The method for dropping a payload according to claim 14 , further comprising the step of providing the target location to the parachute system prior to the launching step.
26. The method for dropping a payload according to claim 14 , further comprising the step of transmitting control information to the parachute system for controlling the guidance parachute.