METHOD FOR CONTROLLING AN AIRCRAFT IN THE FORM OF A MULTICOPTER AND CORRESPONDING CONTROL SYSTEM

• US 20150212523A1
• Filed: 05/17/2013
• Published: 07/30/2015
• Est. Priority Date: 05/21/2012
• Status: Active Grant

• Current Assignee: Volocopter GmbH
• Original Assignee: E-Volo GmbH (Volocopter GmbH)
• Inventors: Wolf, Stephan, Ruf, Thomas
• Granted Patent: US 9,618,939 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: B64C 11/46 Arrangements of, or constructional features peculiar to, multiple propellers B64C11/306 takes precedence
• CPC Class Codes: B64C 27/08 with two or more rotors
• CPC Class Codes: B64C 27/57 automatic or condition responsive, e.g. responsive to rotor speed, torque or thrust
• CPC Class Codes: B64D 45/00 Aircraft indicators or protectors not otherwise provided for camouflage F41H3/00
• CPC Class Codes: B64D 47/00 Equipment not otherwise provided for
• CPC Class Codes: G05D 1/0088 characterized by the autonomous decision making process, e.g. artificial intelligence, predefined behaviours using knowledge based models G06N5/00
• CPC Class Codes: G05D 1/0808 specially adapted for aircraft
• CPC Class Codes: G05D 1/101 specially adapted for aircraft

Abstract

A method and a system are provided for controlling an aircraft in the form of a multicopter which has a plurality of redundant rotors (4), preferably arranged in a common rotor plane, in order, on the one hand, to generate lift, and, on the other hand, also propulsion by inclining the at least one rotor plane, wherein the regulation of the position and the control of the multicopter are carried out by changing rotor rotational speeds as a function of pilot control instructions. The system is characterized in that the rotors (4) are connected to one another in terms of data technology via a failsafe network (8), and they communicate their respective operating state, in particular their rotor rotational speed, in the network (8), and in that the network contains a first multiplicity of redundant sensors which determine control-relevant data and make it available in the network, in particular inclination, acceleration, rotational speed and/or position in all three spatial axes of the multicopter.

Claims

1. A method for controlling an aircraft in the form of a multicopter, which comprises redundant rotors (4) arranged in a common rotor plane, in order to generate lift and, also propulsion by an inclining of at least one rotor plane, with the position control and the control of the multicopter occurring by changes of the rotary speeds of the rotors depending on pilot control instructions, the method comprising

connecting the rotors (4) to each other in a data-technology fashion via a failsafe network (8), communicating their respective operating state including a rotary speed;

determining using, a first plurality of redundant sensors (9,b,c,d) included in the network, data relevant for the control and making the data available in the network (8), including at least one of an incline, acceleration, yaw rate, or position in all three spatial axes of the multicopter;

providing a second plurality of controls (7) in the network (8), and using said second plurality of controls for autonomously and decentrally determining respectively, based on the sensor data a control signal for at least one of the rotors (4) each and making the control signal available in the network (8); and

controlling the rotors (4) by the control signals such that a flight behavior of the multicopter is essentially equivalent to the specifications from pilot control instructions.

2. The method according to claim 1, wherein the rotors (4), the controls (7), and the sensors (9b,c,d) are electrically supplied by a third plurality of power supply units (10).

3. The method according to claim 1, wherein at least one of the second plurality is equivalent to the number of rotors (3), the third plurality is equivalent to the number of rotors (4), or the second plurality is equivalent to the third plurality.

4. The method according to claim 1, wherein a data exchange between at least one of the rotors (4), the controls (7), or the sensors (9b,c,d) occurs by way of data distribution the network (2).

5. The method according to claim 1, wherein output signals of all of the sensors (9b,c,d) are transmitted to all of the controls (7).

6. The method according to claim 1, wherein every network hub in the form of a sensor (9b,c,d), control (7), or rotor (4) in the network regularly transmits a status signal.

7. The method according to claim 1, wherein output signals of the sensors (9b,c,d) are compared with each other, and a selection occurs of an actual value describing the flight status of the multicopter by way of forming a median.

8. The method according to claim 1, wherein output signals of the sensors (9b,c,d) are compared with each other, and at least one of a warning signal is generated or a warning message is indicated for the pilot when the sensor values exceed a defined range.

9. The method according to claim 1, wherein at least some of the controls (7) provide a control signal for respectively more than one of the rotors (4).

10. The method according to claim 1, wherein output signals of the controls (7) are compared with each other and, in case of a distribution of the respective control signals or adjustment parameters beyond a defined range, at least one of a warning signal is generated or a warning message is displayed for the pilot.

11. The method according to claim 1, wherein output signals of the controls (7) are compared with each other and a selection occurs of an actuating variable for a given one of the rotors (4) by forming a median, with no fixed allocation being given between the rotors (4) and the controls (7).

12. The method according to claim 8, wherein by the warning signal or a signal deducted therefrom a freedom of action of the pilot is automatically limited.

13. The method according to claim 8, wherein at least one of a flight or operating state of the aircraft is indicated to the pilot via at least one display (11b), embodied with single redundancy, with said display (11b) receiving all data communicated in the network (8) as a receiving terminal and regularly checks said data for consistency, and in the event of inconsistencies or the presence of a warning signal, or both, the pilot is informed by an appropriate display and prompted to land.

14. The method according to claim 1, wherein redundant operating elements (11c,d) are provided for pilot control instructions, such as switches or joysticks, with their output signals being provided to all units present in the network (8), such as sensors (9b,c,d), controls (7), or rotors (4), with a decentralized assessment of the pilot control instructions occurring by the controls (7).

15. The method according to claim 1, wherein a start of the aircraft is only enabled when all units present in the network (8), including the sensors (9b,c,d), the controls (7), and the rotors (4) report a regular operating state or the data communicated in the network (8) is consistent, which includes at least one of the following conditions:

a) existing start buttons report a “

start”

-operating state;

b) all of the controls (7) report a regular operating state;

c) all of the power supply units (10) report at least a minimum charging status, for example 80%;

or

d) all of the operating elements (11c,d) for pilot control instructions provide consistent values.

16. The method according to claim 1, wherein in order to select an active operating element for pilot control instructions, said operating element is selected from a plurality of redundant operating elements as the active operating element, for which a plurality of respective selection elements show a respective selection status, with most preferably for the selected operating element the median being selected for each operating parameter provided.

17. The method according to claim 1, wherein only data or data packages are forwarded in the network (8), in which a constantly updated forwarding counter has not exceeded a predetermined threshold or which did not originate in the presently forwarding network participant itself.

18. The method according to claim 1, wherein a rate limitation per sender occurs in the network (8), with direct neighbors of each of the network participants recording a transmission time and a number of a last n, n=1,2,3, . . . , data or data packages of said network participant, and when a threshold is reached, at least one of a warning signal is generated or the respective data or data packages are discarded.

19. The method according to claim 1, wherein in the network (8) data packages are collected and summarized at network hubs, and subsequently forwarded in a regular cycle, or the data incoming at the respective hubs is immediately forwarded, if it is more recent than any of the data already present in the hub.

20. The method according to claim 1, wherein the data transmission in the network (8) occurs optically or electrically.

21. A control system for an aircraft in the form of a multicopter, which comprises several rotors (4) arranged in a common rotor plane, in order to generate lift and propulsion by inclining at least one rotor plane, with a position control and control of the multicopter occurring by changing the rotor speeds depending on the pilot control instructions,

the rotors (4) are connected to each other via a failsafe network (8) in a data-technological fashion, and embodied to communicate a respective operating state in the network (8);

a first plurality of redundant sensors (9b,c,d) provided in the network (8) are embodied to determine data relevant for the control and render said data available in the network (8), including at least one of an incline, an acceleration, a yaw rate, or a position in all three spatial axes of the multicopter;

a second plurality of controls (7) in the network (8), embodied to determine autonomously and decentrally, based on sensor data and preferably also based on the operating states of the rotors, respectively a control signal for respectively at least one rotor (4) and render it available in the network (8);

the rotors being adjustable (4) via control signals such that a flight behavior of the multicopter is essentially equivalent to specifications of the pilot control instructions.

22. A system according to claim 21, wherein a third plurality of power supply units is provided for electric supply to the rotors (4), the controls (7), and the sensors (9b,c,d), with at least one of the second plurality being equivalent to the number of rotors (4) the third plurality being equivalent to the number of rotors (4), the second plurality being equivalent to the third plurality.

23. The system according to claim 21, wherein the network (8) is designed and implemented such that any data exchange between at least one of the rotors (4), the controls (7), or the sensors (9b,c,d) occurs via data distribution in the network (8).

24. The system according to claim 21, wherein the network (8) is embodied and implemented such that the output signals of all of the sensors (9b,c,d) are transmitted to all of the controls (7).

25. The system according to claim 21, wherein every one of the network hubs in the form of the sensor (9b,c,d), the controls (7), or the rotors (4) is embodied and implemented to regularly send a status signal to the network (8).

26. The system according to claim 21, wherein the controls (7) are embodied to compare output signals of the sensors (9b,c,d) with each other, and to perform a selection of an actual value describing the flight status of the multicopter by forming a median.

27. The system according to claim 21, wherein the controls (7) are embodied to compare the output signals of the sensors (9b,c,d) with each other, and in case of a distribution of the sensor values beyond a defined range generating at least one of a warning signal or initiating an alarm message for the pilot.

28. The system according to claim 21, wherein at least some of the controls (7) are embodied to provide a control signal for respectively more than one of the rotors (4).

29. The system according to claim 21, wherein the controls (7) are embodied to compare output signals of the controls (7) with each other, and in case of a distribution of the respective actuating variables beyond a defined range to generate at least one of a warning signal or issue a warning message for the pilot.

30. The system according to claim 21, wherein the controls (7) are embodied to compare output signals of the controls (7) with each other, and perform a selection of an actuating variable for a given on of the rotors (4) by forming a median.

31. The system according to claim 27, further comprising at least one display (11b), embodied at least with single redundancy, which is embodied to indicate to the pilot at least one of a flight or operating state of the aircraft, said display (11b) is embodied for the purpose to receive all data communicated in the network (8) as a receiving terminal, to regularly check for consistency, and in case of inconsistencies or the presence of a warning signal to inform the pilot by an appropriate.

32. The system according to claim 21, wherein by redundant ones of the operating elements (11c,d) for pilot control instructions, the output signals are rendered available to all units present in the network (8), such as the sensors (9b,c,d), the controls (7), or the rotors (4), and the controls (7) are embodied to perform a decentralized assessment of the pilot control instructions.

33. The system according to claim 21, wherein in order to select an active operating element (11c) for pilot control instructions, a plurality of respective selection elements (11d) is provided, from a plurality of redundant operating elements, with the system being embodied to select the operating element as the active operating element, for which a plurality of selection elements indicate a respective selection status.

34. The system according to claim 21, wherein the network (8) is configured such that only data or data packages are forwarded, in which a constantly updated forwarding counter has not exceeded a predetermined threshold or with said data not originating in the presently forwarding network participant, or both.

35. The system according to claim 21, wherein the network (8) is configured such that a rate limitation per transmitter occurs in the network (8), with direct neighbors of each of the network participants being embodied to record the transmission time and a number of a last n, n=1,2,3, . . . data or data packages of said network participants, and upon reaching a threshold, at least one of generating a warning signal or discarding the respective data or data packages.

36. The system according to claim 21, wherein the network (8) is configured such that the data packages are collected and summarized at the networks hubs in the network (8), and subsequently forwarded in a cycle, or that data received at the respective hub is immediately forwarded when it is more recent than the data already present in the hub.

37. The system according to claim 21, wherein the network (8) is embodied for optic or electronic data transmission.

38. The system according to claim 21, wherein the network (8) is embodied with multiple redundancies, or in the form of several redundant networks, or as a meshed network without any central element.

39. The system according to claim 21, wherein for each hub within the network (8) respectively three or more connections are provided to neighboring hubs, with a first subset of connections being embodied as inputs (I1, I2) and a second subset of connections being embodied as outputs (O1, O2).

40. An aircraft in the form of a multicopter, which comprises several redundant rotors (4) arranged in a common rotor plane, each including respectively at least one electric motor (1) and a propeller (3), in order to generate lift and propulsion by inclining at least one rotor plane in space, with a position control and control of the multicopter occurring by changes of the rotor speeds depending on pilot control instructions, and

the multicopter comprises a control system according to claim 21.