CONTROL DEVICE FOR THE DRIVE OF A CHASSIS

Description

[0001] The present invention relates to the field of aeronautics and more particularly to the piloting of aircraft on the ground. Technological background

[0002] Aircraft need to be moved on the ground between the takeoff / landing runway and their parking space. Some of these movements follow a straight or curved trajectory with a large radius and are carried out at a relatively high speed (known as "taxiing"). Other movements precede the aircraft's stop or follow a curved trajectory with a small radius and must therefore be carried out at a reduced speed (known as "maneuvering").

[0003] Typically, these movements are made using: either, for forward movements, the main engine of the aircraft, i.e. the one used for aerial maneuvers, generally a thermal engine; or, for backward movements, a land vehicle attached to the aircraft's front landing gear leg.

[0004] Such an aircraft has a relatively high overall fuel consumption given the use of the main engine on the ground and in flight.

[0005] To remedy this, it is known to provide the aircraft with a device for rotating one or more wheels of the aircraft's landing device so as to enable it to move on the ground without using its main engine.

[0006] To move towards more electric or all-electric aircraft, the rotary drive device uses one or more electric motors which are controlled by an electronic control unit connected to a pilot interface installed in the cockpit of the aircraft.

[0007] However, this arrangement leads to a break in the habits of pilots who encounter difficulties in feeling completely comfortable when taxiing.

[0008] It is known from document US-A-2016 / 170435 to have a piloting interface which comprises a control element that the pilot of the aircraft can move to emit control signals that the electronic control unit is arranged to transform into engine piloting signals and which is arranged to determine minimum and maximum speeds in forward gear and minimum and maximum speeds in reverse gear. Other similar motorization devices for moving an aircraft on the ground are known from documents FR2944775A1, US2017 / 057624A1 and US2009 / 261197A1. Subject of the invention

[0009] An object of the invention is to provide a means to facilitate the piloting of the aircraft on the ground. Brief description of the invention

[0010] For this purpose, a motorization device according to claim 1 is provided according to the invention.

[0011] The aircraft's ground movements include movements along straight trajectories and movements along curved trajectories. Straight movements must be able to be carried out at a speed between a minimum speed and a maximum speed depending on whether the pilot wishes to stop soon or, on the contrary, cross a takeoff / landing runway as quickly as possible. The maximum speed of curved movements is conditioned by the radius of the curved trajectories: the smaller this radius, the lower the maximum possible speed. The invention allows easy piloting of the aircraft in each of these phases.

[0012] Maximum speeds are determined based on the aircraft's ground dynamics resulting from the height of the aircraft's center of gravity and the landing gear track, for example.

[0013] Other characteristics and advantages of the invention will emerge from reading the following description of a particular and non-limiting embodiment of the invention. Brief description of the drawings

[0014] Reference will be made to the attached drawings, including: there figure 1 is a partial schematic view, in perspective, of an aircraft according to the invention; the figure 2 is a block diagram of the aircraft control according to a first embodiment of the invention; the figure 3 is a block diagram of the aircraft control according to a second embodiment of the invention; figure 4 is a schematic view of the control interface according to a first embodiment; the figure 5 is a schematic view of the control interface according to a second embodiment. Detailed description of the invention

[0015] The invention is described, with reference to the figures, in application to an aircraft, here an airplane A, provided with landing gear of which a front landing gear L provided with wheels W is shown in the figure 1 The front landing gear L is known in itself and will not be described in further detail here.

[0016] Aircraft A is equipped with a power unit, generally designated 1, to move aircraft A on the ground.

[0017] The motorization device 1 comprises an electric motor 2 having an output shaft provided with means for its rotational connection to the wheels W of the front landing gear L to drive said wheels W in rotation.

[0018] The motorization device also comprises an electronic control unit 3 connected, on the one hand, to the electric motor 2 to control it and, on the other hand, to a piloting interface 4 which is arranged in the cockpit of the aircraft A. From the piloting interface 4, the pilot of the aircraft A can emit control signals which the electronic control unit 3 is arranged to transform into signals for piloting the engine 2.

[0019] The electronic control unit 3 comprises a processor (or another type of calculator such as an ASIC type circuit, an FPGA, a microcontroller, etc.) and a memory containing at least one program containing instructions arranged for the implementation of a control program for the motorization device 1.

[0020] The control program executed by the electronic control unit 3 comprises several control laws implementing control loops and strategies to control the motor 2 according to the electrical signals emitted by the control interface 4, namely: a first control law having a determined dynamic to promote a speed of movement of the aircraft A, a second control law having a dynamic promoting maneuverability of the aircraft A in a forward direction, a third control law having a determined dynamic to promote maneuverability of the aircraft A in a backward direction.

[0021] With particular reference to the figure 4 , the piloting interface 4 comprises a switch 50 for activating the motorization which is movable between an “ON” position and an “OFF” position, and a control element 10, such as a joystick, arranged to be movable by the pilot of the aircraft A along a first scale 11 and a second scale 12 parallel to each other and connected to each other by a connecting section 13 comprising a neutral point 14.

[0022] The first scale 11 comprises two ends 11.1, 11.2 corresponding respectively to a maximum speed and a minimum speed, here zero, to control the electric motor 2 between these two speeds, depending on the position of the control element 10 along the first scale 11, by implementing the first control law.

[0023] The second scale 12 comprises a first section 12.1 having a first end corresponding to a maximum forward speed and a second end which corresponds to a zero speed and which is connected to a first end of a second section 12.2 having a second end corresponding to a maximum reverse speed. The control element 10 is movable along the second scale 12 to control the engine between one of the two maximum speeds and the zero speed depending on the position of the control element 10: by implementing the second control law when the control element 10 is in the section 12.1; by implementing the third control law when the control element 10 is in the section 12.2.

[0024] For a given displacement amplitude of the control element 10, the first control law determines a predetermined acceleration: greater than the acceleration determined by the second control law for the same amplitude of displacement of the control element 10; greater than the acceleration determined by the third control law for the same amplitude of displacement of the control element 10.

[0025] Furthermore, the maximum speed achievable with the first control law is higher than that achievable with the other two control laws.

[0026] For a given displacement amplitude of the control element 10, the second control law determines a predetermined acceleration (for example an acceleration of 4 kn per second, it is recalled that 1 kn, or knot, is equal to 1852 m / h) greater than the acceleration determined by the third control law (for example 0.5 kn per second) for the same displacement amplitude of the control element 10. Alternatively, for a given displacement amplitude of the control element 10, the second control law determines a predetermined acceleration equal to, or less than, the acceleration determined by the third control law for the same displacement amplitude of the control element 10.

[0027] The acceleration predetermined by the first control law is compatible (i.e. more suitable) with movement in a straight line or along curved trajectories with large radii (resulting from a steering angle of the front landing gear leg between 0° and 30° for example) at relatively high speed such as during taxiing (at a speed between 10 and 20 kn for example).

[0028] The acceleration predetermined by the second control law is more suitable for making small radius turns (resulting from a steering angle of the front landing gear leg between 31° and 74° for example) at relatively low speed (less than 10 kn for example) such as entering or leaving a parking space.

[0029] According to the figure 3 also, the motorization device being stopped (100), the pilot who wishes to use the motorization device actuates the switch 50 (105) causing the motorization device 1 (110) and the control unit 3 to be switched on, which ensures a check of the state of the motorization device (115). The pilot then chooses by moving the control element 10 the type of rolling he wishes to carry out (120) and the direction of rolling (125). The control unit 3 will then control the electric motor 2 (130) by applying the control law resulting from the pilot's choice (131 for the first control law, 132 for the second, 133 for the third).

[0030] According to the second embodiment shown in the figure 5 , the electronic control unit 3 only implements a first control law for taxiing and a second control law for forward and reverse maneuvers. The control interface 4 comprises: a control element 10 arranged to be movable by the pilot of the aircraft 3 along a scale 11 comprising two ends 11.1, 11.2 corresponding respectively to a maximum speed and a minimum speed to control the electric motor 2 between these two speeds depending on the position of the control element 10 along the scale 11; a member for selecting the first control law or the second control law, here a switch 20; a member for selecting a direction of rotation of the electric motor 2 during the implementation of the second control law, here a switch 30.

[0031] The switch 20 pivots here between a taxiing position “Taxi” to command the control unit 3 to apply the first control law and a maneuvering position “Man” to command the control unit 3 to apply the second control law.

[0032] The switch 30 pivots here between a “Forward” position to command the control unit 3 to drive the motor 2 forward and a “Reverse” position to command the control unit 3 to drive the motor 2 in reverse. It will be noted that the control unit 3 is arranged to take into account the selection of the forward or reverse direction only when the switch 20 is in the maneuvering position, in the taxiing position only forward movement being possible. It can be provided that placing the switch 20 in the taxiing position causes an LED on the switch 30 to light up to indicate that it is activated.

[0033] The corresponding operating mode is described in figure 2 .

[0034] Of course, the invention is not limited to the embodiment described but encompasses any variant falling within the scope of the invention as defined by the claims.

[0035] In particular, the device may have a structure different from that described.

[0036] The device of the invention can be used for the motorization of one or more wheels of an aircraft. The device can comprise two electric motors each associated with one of the main landing gears and connected to the wheels of this main landing gear.

[0037] The switches 20, 30 can be replaced by any other device allowing selection and for example switches such as push buttons.

[0038] The control element 10 can be replaced by any device allowing continuous variation such as for example a potentiometer. The control element 10 could also be replaced by a switch allowing speed selection from predefined values. A speed selection switch could be provided for taxiing and a speed selection switch for maneuvering, the actuation of one or other of the switches automatically selecting the corresponding control law.

[0039] The control element 10 and the switches 20, 30 can also be replaced by one or more touch screens.

[0040] The operating mode may be different from that described. For example, the motorization device may be arranged so as not to operate in reverse. The operating mode corresponds to that of the figure 2 without operation 125.

[0041] A single reverse speed can also be provided.

[0042] Steering angles or speeds mentioned may differ from those given as a guide in the description.

Claims

1. A motorizing device (1) for moving an aircraft (A) equipped with a landing device (L) having wheels (W) on the ground, the motorizing device comprising at least one electric motor (2) having an output shaft provided with means for its rotational connection to at least one of the wheels (W) of the landing device for driving said wheel in rotation, and an electronic control unit (3) connected on the one hand to the motor to control it and on the other hand to a control interface (4) comprising a control element that the aircraft pilot can move to transmit control signals which the electronic control unit is arranged to transform into motor control signals, the control unit being arranged to implement a first control law having determined dynamics to promote an aircraft movement speed and a second control law having dynamics to promote aircraft manoeuvrability, characterized in that the first control law determines a predetermined acceleration greater than an acceleration determined by the second control law for the same movement amplitude of the control element (10).

2. A device according to claim 1, wherein the control unit is arranged to implement a third control law having determined dynamics to promote manoeuvrability of the aircraft, the second control law being arranged to control the motor in a forward direction and the third control law being arranged to control the motor in a reverse direction.

3. A device according to claim 1 or 2, wherein the control element (10) is arranged to be movable by the pilot of the aircraft along a first scale (11) and a second scale (12) parallel to each other and connected to each other by a connecting section (13) including a neutral point, the first scale including two ends (11.1, 11.2) corresponding respectively to a maximum speed and a minimum speed to control the motor between these two speeds according to the position of the control element by implementing the first control law and the second scale comprising two ends corresponding respectively to a maximum speed and a minimum speed to control the motor between these two speeds according to the position of the control element by implementing the second control law.

4. A device according to claim 3, wherein the second scale (12) comprises a first section (12.1) having a first end corresponding to a maximum forward speed and a second end corresponding to a zero speed and which is connected to a first end of a second section (12.2) having a second end corresponding to a maximum reverse speed.

5. A device according to claim 3, wherein the control interface (4) comprises a selection element (30) for selecting a direction of rotation of the motor (2) during the implementation of the second control law.

6. A device according to claim 1 or claim 2, wherein the control interface (4) comprises a control element (10) arranged to be movable by the pilot of the aircraft along a scale (11) comprising two ends corresponding respectively to a maximum speed and a minimum speed to control the motor between these two speeds according to the position of the control element, and a selection element (20) of the first control law or the second control law.

7. A device according to claim 6, wherein the control interface (4) comprises a selection element (30) for selecting a direction of rotation of the motor during the implementation of the second control law.