Wireless control system for production of reconfigurable and / or frameless autonomous unmanned vehicles

Abstract

Described herein is a wireless control system (100) for production of reconfigurable and / or frameless autonomous unmanned vehicles, which comprises a central control unit (AP) configured to generate control signals for controlling a propulsion unit (25), a transmitter module (15) configured to analyze the control signals generated by the central control unit (AP) and transmit data related to said signals to a receiver module (21) via an ultra-wide band (UWB) protocol, the receiver module (21) configured to decode the data transmitted by the transmitter module (15) and generate control signals supplied to an electronic control module ESC by replicating the control signals generated by the central control unit (AP), the electronic control module (ESC) configured to receive the control signals generated and supplied by the receiver module (21) and drive a propulsion unit (25), the propulsion unit (25).

Description

[0001] WIRELESS CONTROL SYSTEM FOR PRODUCTION OF RECONFIGURABLE

[0002] AND / OR FRAMELESS AUTONOMOUS UNMANNED VEHICLES

[0003] DESCRIPTION

[0004] The present invention relates to a wireless control system for production of reconfigurable and / or frameless autonomous unmanned vehicles.

[0005] In particular, the invention relates to a wireless rotor control system for the production of reconfigurable and / or frameless autonomous multi-rotor unmanned vehicles (drones).

[0006] More specifically, the present invention is applicable to a wireless control system for production of autonomous UAVs (Unmanned Aerial Vehicles), UGVs (Unmanned Ground Vehicles), also known as “Rovers”, or UUVs (Unmanned Underwater Vehicles).

[0007] Multi -rotor autonomous unmanned aerial vehicles (UAVs) are known which are widely used in the military, private and industrial fields due to their efficiency and their ability to reach, without requiring a pilot aboard, locations hardly accessible to humans. In particular, said autonomous multi-rotor unmanned aerial vehicles are used in the construction industry, for refinery inspections, in precision agriculture applications, during rescue operations, and for aerial photography. They are also employed in the medical field for transporting drugs, organs and medical devices, as well as in the space industry for studying extraterrestrial environments. Drones are also used for delivering products in advanced logistic applications, thus reducing road traffic and ensuring higher efficiency and faster shipping.

[0008] These known autonomous multi-rotor unmanned aerial vehicles comprise an electronic control system, called avionics, installed on a rigid frame that cannot be dynamically modified at will.

[0009] One problem of such autonomous known multi-rotor unmanned aerial vehicles is that, since they require a wired connection between the “on-board computer” and the motor controllers, the motors can be used in a single configuration only, which limits the load types that can be transported.

[0010] The present invention aims at solving the above-mentioned drawbacks of the prior art by providing a system which, by controlling the motors in wireless mode, can ensure a higher level of flexibility of the vehicle, making it reconfigurable and adaptable to the type of load to be transported. The above objects and other purposes and advantages of the invention, which will become clear in light of the following description, are achieved through a wireless control system as described in the independent claim. Some preferred embodiments and non-obvious variations of the present invention are set out in dependent claims.

[0011] It is understood that all the attached claims form an integral part of the present description.

[0012] It will become immediately apparent that what is described herein may be subject to innumerable variations and modifications (e.g. in shape, dimensions, arrangements and parts having equivalent functionality) without departing from the protection scope of the invention as set out in the appended claims.

[0013] The present invention will be described in detail below through some preferred embodiments thereof, which are only provided by way of non-limiting example, with reference to the annexed drawings, wherein:

[0014] FIG. 1 shows a schematic representation of a control system according to the present invention;

[0015] FIG. 2 shows a schematic representation of a control system according to the present invention;

[0016] FIG. 3 shows a schematic view of a wireless control system for controlling rotors of autonomous multi-rotor unmanned vehicles according to the present invention;

[0017] FIGS. 4 and 5 show two schematic representations of two embodiments of a control system according to the present invention.

[0018] With reference to the drawings, the wireless control system 100 for production of reconfigurable and / or frameless autonomous unmanned vehicles according to the present invention comprises:

[0019] - a central control unit AP configured to generate control signals for controlling a propulsion unit 25, preferably control signals for driving electric motors 25;

[0020] - a transmitter module 15 configured to analyze the control signals generated by the central control unit AP and transmit data related to said signals to a receiver module 21 via a low- latency ultra-wide band (UWB) protocol;

[0021] - the receiver module 21 configured to decode the data transmitted by the transmitter module 15 and generate control signals supplied to an electronic control module ESC by replicating the control signals generated by the central control unit AP; - the electronic control module ESC (Electronic Speed Controller), configured to receive the control signals generated and supplied by the receiver module 21 and drive a propulsion unit 25; preferably, the electronic control module ESC is a driver of an electric motor 25 on which the receiver module 21 is installed;

[0022] - the propulsion unit 25, preferably comprising a rotor 26 driven by an electric motor 25.

[0023] The following will describe a preferred embodiment of the invention, wherein the control system 100 is a wireless rotor control system for production of reconfigurable and / or frameless autonomous multi-rotor unmanned aerial vehicles, preferably a modular aerial platform or a modular drone.

[0024] The present invention is also applicable to a wireless control system for production of UGVs (Unmanned Ground Vehicles), also known as “Rovers”, or UUVs (Unmanned Underwater Vehicles).

[0025] The wireless control system 100 for production of reconfigurable and / or frameless autonomous unmanned vehicles according to the invention comprises two modules: a main unit 10 (master), which houses the transmitter module 15 responsible for the interpretation of PWM (Pulse-Width Modulation) signals generated by the central control unit AP, also referred to as on-board computer, Autopilot, or autopilot, and for the transmission of the same using UWB technology, and a peripheral unit 20 (slave), which decrypts the messages received from the main unit 10 (master) and generates PWM (Pulse-Width Modulation) signals for controlling the electronic control module ESC.

[0026] Preferably, the wireless rotor control system 100 for the production of reconfigurable and / or frameless autonomous multi-rotor unmanned vehicles according to the invention comprises a main unit 10 (master) and at least one peripheral unit 20 (slave), more preferably three or more peripheral units 20.

[0027] Preferably, the main unit 10 (master) comprises:

[0028] - the central control unit AP (on-board computer) configured to generate control signals for electric motors, in particular one independent signal per motor, preferably PWM (Pulse- Width Modulation) signals;

[0029] - a radio receiver 11 configured to acquire commands from a remote control device and transmit them to the central control unit AP (on-board computer);

[0030] - the transmitter module 15 configured to analyze the control signals, preferably PWM (Pulse-Width Modulation) signals, generated by the central control unit AP (on-board computer), generate data related to the control signals, and transmit them to the receiver module 21 of at least one peripheral unit 20 (slave) through a low-latency ultra-wide band UWB protocol; the control-signal data transmitted to the peripheral unit 20 (slave) comprise data about the duty cycle DC of the signal and an address (ADDR1 -ADDRn) of each receiver module 21 for replicating the control signal to be used for driving the motor 25; the duty cycle DC is defined as the ratio between the time during which the wave is in a High state and the period T;

[0031] - an electric power supply unit 12 (battery).

[0032] Preferably, the peripheral unit 20 (slave) comprises:

[0033] - the receiver module 21 configured to receive and decode the data transmitted by the transmitter module 15 through the ultra-wide band (UWB) protocol, generate PWM (Pulse- Width Modulation) control signals replicating the control signals generated by the central control unit AP (on-board computer), and supply them to the electronic control module ESC;

[0034] - an electronic control module ESC (Electronic Speed Controller), configured to receive the control signals generated and supplied by the receiver module 21 and drive an electric motor 25;

[0035] - the propulsion unit, comprising a rotor 26 driven by the electric motor 25;

[0036] - an electric power supply unit 12 (battery);

[0037] - gripping means 27 for gripping the load 30 to be transported, e.g. a clamp.

[0038] Preferably, each peripheral unit 20 (slave) comprises an inertial measurement unit (IMU), which is used for computing the position of each motor 25 by combining the information supplied by the UWB modules 15, 21 (the UWB modules perform a dual function: controlling the electronic control module ESC and measuring the distance between said UWB modules) with the data provided by the inertial measurement units (IMU) (i.e. acceleration values and angular speed values).

[0039] The computed position of each motor 25, wherein each one of the motors 25 is comprised in one peripheral unit 20, is used in order to determine a kinematic model for the modular drone. The term “modular drone” refers to the drone generated by the union of a plurality of peripheral units 20, one main unit 10, and a load 30 to be transported, which acts as a frame for said modular drone. The plurality of peripheral units 20 can be associated with the load 30 arbitrarily as concerns both their position and their number. It follows that the computation of the position of each peripheral unit 20 permits determining a geometry and a plurality of inertial parameters that are specific for the modular drone generated by the configuration derived from such association. The geometry and the inertial parameters make it possible to optimize the stability of the modular drone resulting from a specific association. During a preliminary phase of identifying the rigid body, representative of the modular drone, each motor 25 is activated in succession, so that the activated motor 25 will generate a thrust force capable of causing at least a partial movement of the rigid body. Such movement is measured by an inertial measurement unit IMU provided on the peripheral unit 20 and configured to supply a plurality of data such as, for example, acceleration, inclination, rotation and magnetic angle values. The inertial measurement unit IMU is also configured to provide a mutual distance from other motors 25 of the plurality of peripheral units 20 that are present on the modular drone, such distances being provided as relative distances between pairs of motors 25. The relative distances between the pair of motors 25 and the information measured for each motor 25 are then sent to the central unit 10. The central unit 10 comprises an algorithm configured to combine the information about the relative distances between pairs of motors 25 and the plurality of data belonging to the activations of the motors 25 of the modular drone, so that said algorithm will determine a kinematic model of the rigid body, defined by computing estimated coordinates of the plurality of motors 25 relative to a geometric center of said modular drone and by computing corresponding inertial parameters. During a subsequent movement phase of the modular drone, the kinematic model thus determined is used by the central unit 10 in order to define the control signals to be independently sent to each motor 25. Such signals are computed on the basis of the position of each motor 25 relative to the geometric center defined for the kinematic model. In particular, when the central control unit AP receives a command from the radio receiver 11 , issued by a remote control device, the central control unit AP is suitable for determining in real time a force that each motor 25 will have to generate, based on the kinematic model, to allow the modular drone to execute the received command.

[0040] The generation of control signals independently defined for each motor 25 of the plurality of motors 25 available on the modular drone leads to increased stability of the vehicle in motion, said control signals being encapsulated into a single message directly transmitted from the central control unit AP to the plurality of peripheral units 20.

[0041] The control signals for each motor 25, encapsulated into a single message transmitted from the central control unit AP, are directly received by the control modules integrated into the motors 25. This results in optimized reactivity and increased stability of the modular drone in motion.

[0042] Preferably, the main unit 10 (master) may be integrated into a peripheral unit 20 (slave), to which the central control unit AP (on-board computer), the radio receiver 11 and the transmitter module 15 are added.

[0043] The operation of the wireless rotor control system 100 for the production of reconfigurable and / or frameless multi-rotor unmanned vehicles according to the invention is based on the acquisition of motor control signals generated by the central control unit AP (on-board computer) and on the transmission of the same to the rotors using wireless techniques. Such signals are analyzed by the transmitter module 15 and then sent, via the ultra-wide band (UWB) protocol, to the receiver modules 21 installed on the peripheral units 20 (slaves), preferably on the individual motor drivers. Upon reception, the receiver modules 21 decode the packets and generate control signals that are supplied to the motor drivers responsible for driving the rotors of the aircraft.

[0044] The encoded packets are transmitted in broadcast mode to the plurality of receiver modules 21 via said ultra-wide band (UWB) protocol.

[0045] Within the encoded packet, the control signals are associated with an identifier ID of the peripheral unit 20 comprising that specific motor 25 to which the control signals are addressed. During the packet decoding phase, the receiver module 21 belonging to the peripheral unit 20 identified by the ID will only retrieve from the packet those control signals which are associated with that ID. For example, a first receiver 21 identified as ID1 will check the packet for control signals associated with the identifier ID1, while a second receiver 21 identified as ID2 will check the packet for control signals associated with the identifier ID2.

[0046] By providing wireless rotor control, the control system according to the invention advantageously ensures a higher level of flexibility of the aircraft, making it configurable and adaptable to the type of load to be transported.

[0047] Unlike conventional high-level wireless control systems, the present system implements a low-level control mode for controlling the motors 25 directly. Such control is achieved by means of control signals transmitted in wireless mode using UWB technology, allowing for direct communication between the central control unit AP and each motor 25. The control signals defined for each motor 25 are not, therefore, exclusively processed by intermediate or peripheral units, but directly addressed to the motors 25, thus ensuring an immediate and accurate response to the received commands.

[0048] A further advantage of the architecture according to the present invention, which is based on low-level control via UWB, lies in the fact that it eliminates the need for complex intermediate processing aboard the peripheral units 20 (slave), thus allowing for direct and synchronous management of the motors 25. The control signals for each motor 25, which are encapsulated into a single message transmitted by the central control unit AP, are received directly by the control modules integrated into the motors 25 themselves. This results in optimized reactivity and increased stability of the modular drone in motion.

[0049] Lastly, when the main unit 10 (master) is integrated into one of the peripheral units 20 (slave), which thus comprises the central control unit AP (on-board computer), the radio receiver 11, the transmitter module 15, and the ultra-wide band transmission / reception functions for direct motor control, the global architecture is simpler and ensures a reduction in the latency of the control processes.

[0050] The preferred embodiments of the invention described herein may of course be subject to further modifications and variations without departing from the inventive idea. In particular, it will be immediately apparent to those skilled in the art that numerous functionally equivalent variations and modifications will fall within the protection scope of the invention, as highlighted in the appended claims, wherein any references between brackets should not be understood to limit the claims themselves. Furthermore, the word “comprising” shall not exclude the presence of elements and / or steps other than those listed in the claims. The article “a” or “an” before an element shall not exclude the presence of a plurality of such elements. The simple fact that some features are mentioned in distinct dependent claims shall not imply that a combination of such features cannot be used to advantage.

Claims

CLAIMS1. Wireless control system (100) for production of reconfigurable and / or frameless autonomous unmanned vehicles, which comprises:- a central control unit (AP) configured to generate control signals for controlling a propulsion unit (25);- a transmitter module (15) configured to analyze the control signals generated by the central control unit (AP) and transmit data related to said signals to a receiver module (21) via an ultra-wide band (UWB) protocol;- the receiver module (21) configured to decode the data transmitted by the transmitter module (15) and generate control signals supplied to an electronic control module ESC by replicating the control signals generated by the central control unit (AP- the electronic control module (ESC) configured to receive the control signals generated and supplied by the receiver module (21) and drive a propulsion unit (25);- the propulsion unit (25).

2. Control system (100) according to claim 1, characterized in that it comprises two modules: a main unit (10), housing the transmitter module (15) responsible for the interpretation of PWM signals generated by the central control unit (AP) and for the transmission of the same using UWB technology, and a peripheral unit (20), which decrypts the messages received from the main unit (10) and generates PWM signals for controlling the electronic control module (ESC).

3. Control system (100) according to claim 2, characterized in that the main unit (10) comprises:- the central control unit (AP) configured to generate PWM control signals for electric motors, in particular one independent signal per motor;- a radio receiver (11) configured to acquire commands from a remote control device and transmit them to the central control unit (AP);- the transmitter module (15) configured to analyze the PWM control signals generated by the central control unit (AP), generate data related to the control signals, and transmit them to the receiver module (21) of at least one peripheral unit (20), or slave, via an ultra-wide band (UWB) protocol;- an electric power supply unit (12).

4. Control system (100) according to claim 3, characterized in that the data related to the control signals transmitted to the peripheral unit (20), or slave, comprise data about the duty cycle (DC) of the signal and an address (ADDR1 -ADDRn) of each receiver module (21) for replicating the control signal to be used for driving the motor (25).

5. Control system (100) according to any one of claims 2 to 4, characterized in that the peripheral unit (20) comprises:- the receiver module (21) configured to receive and decode the data transmitted by the transmitter module (15) via an ultra-wide band (UWB) protocol, generate PWM control signals, and supply them to the electronic control module (ESC) by replicating the control signals generated by the central control unit (AP);- the electronic control module (ESC) configured to receive the control signals generated and supplied by the receiver module (21) and drive an electric motor (25);- the propulsion unit comprising a rotor (26) driven by the electric motor (25);- the electric power supply unit (12);- gripping means (27) for gripping a load (30) to be transported.

6. Control system (100) according to claims 2 to 5, characterized in that each peripheral unit (20) comprises an inertial measurement unit (IMU) used for computing the position of each motor (25) by combining the information supplied by the UWB modules (15, 21) with the data provided by the inertial measurement units (IMU).

7. Control system (100) according to any one of claims 2 to 6, characterized in that the main unit (10) may be integrated into a peripheral unit (20), to which the central control unit (AP), the radio receiver (11) and the transmitter module (15) are added.

8. Control system (100) according to any one of the preceding claims, characterized in that the central control unit (AP) is configured to generate control signals for driving electric motors (25), and the propulsion unit comprises a rotor (26) driven by an electric motor (25).

9. Control system (100) according to claim 6, wherein said inertial measurement unit configured to compute the position of each motor (25) is further configured to transmit said computed position and said data emitted by said inertial unit to said central control unit (AP); said central control unit (AP) being configured to determine a plurality of inertial parameters and a position for each one of said motors (25) relative to a geometric center of said reconfigurable and / or frameless autonomous unmanned vehicle in order to generate saidcontrol signals independently for each motor (25), so as to optimize the stability of said reconfigurable and / or frameless autonomous unmanned vehicle in motion.

10. System (100) according to one or more of the preceding claims, wherein said transmitter module (15), configured to transmit said data via said ultra-wide band (UWB) protocol, is further configured to transmit said data in broadcast mode to the plurality of receiver modules (21).

11. Control system (100) according to the preceding claim, wherein said peripheral unit (20) is suitable for being identified by means of an identification code (ID), and said receiver module (21) belonging to said peripheral unit (20) is configured to take from said transmitted data the control signals associated with said ID.

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