Dead reckoning back-up navigational system for a drone

Claim 2

A dead reckoning back up navigational system for a drone comprising, in combination: a. heading storage means for storing the heading to a recovery area; b. range storage means for storing the range of the drone from the recovery area; c. on-board compass means providing the existing heading; d. on-board air speed integrating means; and e. failure trigger means responsive to a failure in the primary navigational system to actuate the heading storage means, range storage means, and air speed integrating means to thereby provide corrective steering command signals to the drone flight control system to cause it to head in the direction defined by the stored heading signal at the time of failure and to land when the integrated air speed equals the stored range at the time of failure, whereby the drone is automatically returned to the recovery area by dead reckoning.

Claim 3

A dead-reckoning back-up navigational system according to claim 1, including wind correction means for modifying the stored heading and range information to take into account wind conditions existing at the time of failure.

Claim 4

A dead reckoning back-up navigational system for a drone on a flight mission under control of an on-board navigational receiver providing position signals indicating the existing position of the drone at all times in relation to fixed ground radio stations, an on-board pre-recorded flight program unit providing program signals indicating pre-programmed positions for the drone, and primary means responsive to deviations of the position signals from the program signals for generating primary command signals to control the drone flight controls in a manner to correct the deviations, said dead-reckoning back-up navigational system including, in combination: a. means connected to the navigational receiver providing existing position signals; b. means connected to the pre-recorded flight program unit providing recovery area signals; c. means on the drone providing wind correction signals; d. heading computer means receiving said existing position signals, recovery area signals, and wind correction signals to generate in response thereto a corrected recovery area heading signal; e. range computer means receiving said existing position signals, recovery area signals, and wind correction signals to generate in response thereto a corrected recovery area range signal; f. heading storage means connected to said heading computer means for continuously storing said corrected recovery area heading signal; g. range storage means connected to said range computer means for continuously storing said corrected recovery area range signal; h. on-board compass means for providing a heading signal of The drone at its existing position; i. steering command signal means responsive to any differences between the on-board compass heading signal and the stored recovery area heading signal to provide a correction steering signal; j. on-board air speed integrating means for providing a range signal indication of the distance the drone has traveled from its existing position; k. landing command signal means responsive to said range signal and the stored recovery area range signal to provide a landing command signal when the range signal equals the stored recovery area range signal; and, l. failure trigger means responsive to a failure in the on-board navigational receiver, on-board pre-recorded flight program unit or primary means providing primary command signals, to disconnect said primary means and activate the heading and range storage means, and the compass means and air speed integrating means, and connect said steering command signal means and said landing command signal means to the drone flight controls, whereby wholly self-contained control of the drone to return it to and land it at the recovery area is provided.

Claim 5

A dead reckoning back-up navigational system for a drone on a flight mission under control of an on-board navigational receiver providing position signals indicating the existing position of the drone at all times in relation to fixed ground radio stations, an on-board pre-recorded flight program unit providing program signals indicating pre-programmed positions for the drone, and primary means responsive to deviations of the position signals from the program signals for generating primary command signals to control the drone flight controls in a manner to correct the deviations, said dead-reckoning back-up navigational system including, in combination: a. means connected to the navigational receiver providing existing position signals; b. means connected to the pre-recorded flight program unit providing recovery area signals; c. means on the drone providing wind correction signals; d. heading computer means receiving said existing position signals, recovery area signals, and wind correction signals to generate in response thereto a corrected recovery area heading signal; e. range computer means receiving said existing position signals, recovery area signals, and wind correction signals to generate in response thereto a corrected recovery area range signal; f. heading storage means connected to said heading computer means for continuously storing said corrected recovery area heading signal; g. range storage means connected to said range computer means for continuously storing said corrected recovery area range signal; h. on-board compass means for providing a heading signal of The drone at its existing position; i. steering command signal means responsive to any differences between the on-board compass heading signal and the stored recovery area heading signal to provide a correction steering signal; j. on-board air speed integrating means for providing a range signal indication of the distance the drone has traveled from its existing position; k. landing command signal means responsive to said range signal and the stored recovery area range signal to provide a landing command signal when the range signal equals the stored recovery area range signal; and, l. failure trigger means responsive to a failure in the on-board navigational receiver, on-board pre-recorded flight program unit or primary means providing primary command signals, to disconnect said primary means and activate the heading and range storage means, and the compass means and air speed integrating means, and connect said steering command signal means and said landing command signal means to the drone flight controls, whereby wholly self-contained control of the drone to return it to and land it at the recovery area is provided.

Claim 6

A dead-reckoning back-up navigational system for a drone according to claim 3, including an altitude storage unit for defining a safe return altitude to the recovery area for comparison and with the actual altitude of the drone in the event of a failure to provide a correction altitude signal to the drone flight control system so that the drone will return to the recovery area at the defined altitude.