FR2974760A1 - Remotely controlled mobile platform for use in water and air mediums to carry out underwater and air recognitions, has switching unit whose reversing unit reverses rotation of electric motors that rotate marine/aerial propellers - Google Patents

Abstract

The platform has four propellants (P1-P4) comprising propulsion axes (Delta1-Delta4), respectively, where the propulsion axes are oriented in two planes parallel to each other and to a longitudinal axis (X-1, X'-1) of the platform. The propellants comprise propulsive marine propellers (HM1-HM4), tractive aerial propellers (HA1-HA4), a switching unit, and electric motors for rotating the marine/aerial propellers. The switching unit switches a coupling between the electric motors and the marine/aerial propellers and comprises a reversing unit for reversing the rotation of the electric motors.

Description

The present invention relates to a remote-controlled mobile platform capable of evolving in a medium such as water and air, in particular for performing underwater and aerial reconnaissance.

It relates more particularly to an energy-autonomous platform remote remotely controllable from a control / command station located on the ground or on a surface vessel, this platform being equipped with means for receiving the pilot data coming from said control station and for transmitting thereto data from on-board sensors aboard said platform, such as a video camera, a geolocation device, a sonar, a bathymetry device, a acoustic navigation beacon, physicochemical sensors or others.

Moreover, in many applications, especially when the platform is brought to evolve in a nerve, hostile or adverse environment, it is desirable that this platform is as little detectable as possible.

Thus, for example, in the case of the radio remote control of an air platform, the question that arises is that of the deletion of the radiofrequency signature.

Similarly, in the case of the acoustic location of an underwater platform, the question that arises is that of the removal of the acoustic signature.

These two requirements are combined in the case of a remote-controlled platform able to evolve in a medium such as water and air, especially for underwater and aerial reconnaissance.

It is clear that in both cases, the platform should be made "silent" while allowing it to evolve, if only to point a target. Of course, this problem appears a priori hardly soluble since the majority of the noise is generated by the propulsion and / or levitation means used which, as a rule, are relatively noisy.

It is known, moreover, that one of the great difficulties that arises in the design of such apparatus lies in the resolution of stability problems, especially in the stationary state, for example when acquisition and maintenance of an orientation for visual or other purposes.

In this respect, the French patent FR 2 796 217, published on February 2, 2001, proposes a remotely controlled mobile platform able to evolve in a medium such as water or air; said platform is characterized in that it has a density close to that of the medium in which it is located and in that it comprises at least two pairs of steerable thrusters in two planes parallel to each other and to the axis longitudinal of the platform.

In the underwater version, the platform is equipped with hydraulic reactors; as for the aerial version, it comprises a dirigible type structure.

It is clear that these two configurations are not compatible in the case of a remote controlled mobile platform able to evolve in a medium such as water and air.

The invention therefore more particularly aims to solve these problems.

It proposes, for this purpose, a platform comprising two pairs of thrusters whose propulsion axes are orientable in two planes parallel to each other and to the longitudinal axis of the platform, knowing that said thrusters comprise an electric motor which can to rotate in either a propeller marine propeller or a tractive air propeller, the coupling switching between one or the other is effected by reversing the direction of rotation of said electric motor.

Thus, the orientation of the thruster propulsion axes, the variation of the speed of rotation of the propellers, and the mode of marine or air propulsion, according to the choice of the direction of rotation of the electric motor, make it possible to evolve the platform. in the water and in the air, meeting the driving requirements in these two environments.

Advantageously, the platform will be equipped with a device for transmitting information between said autonomous platform and a transmitting / receiving station, as described in French patent FR 2 792 478 published on July 13, 2001.

This mode of information transmission via an optical fiber, operating in "full duplex" meets the bandwidth requirements imposed for the real-time transfer of video images; it also meets the requirements defined above, namely: in the case of the radio remote control of an air platform, the question which arises is that of the deletion of the radiofrequency signature, in the case of the acoustic localization of the antenna. 'an underwater platform, the question that arises is that of the suppression of the acoustic signature.

Thus, in the case where the platform is intended to evolve in the aquatic environment, the four propellers will be able to operate thanks to the action of the marine propellers, in propulsive mode, the blades of aerial propellers will be folded under the effect of the flow aquatic, offering low resistance to underwater propulsion.

Similarly, in the case where the platform is intended to evolve in the air, the four thrusters can operate through the action of aerial propellers, in tractive mode, the blades of aerial propellers will be deployed under the centrifugal effect , marine propellers offering low resistance to air propulsion.

Advantageously, the platform, intended to evolve in an air and aquatic environment, will be energetically autonomous, thanks to batteries whose stored energy density is high. Of course, the configuration of the thrusters, in terms of orientation and servocontrol of the speed of rotation of the propellers, in the aquatic environment will be different from that in the air.

More specifically, in the aquatic environment, the orientation of the four propellers will be variable depending on the desired trajectory of the platform (horizontal navigation, dive or ascent), and the rotational speeds of the propellers marine propellers will be variable according to the speed of propulsion and the change of course. In the air environment, the four thrusters will be oriented vertically, the aerial propellers being tractive, and the rotational speeds of these will be variable according to the desired trajectory of the platform (ascent, descent, forward, reverse). and change of course); this mode of operation is similar to that of a swashplate of a rotary wing.

Therefore, this mode of propulsion, whether it is in the aquatic environment or in the air, will make it possible to perform starboard / port turnover maneuvers, climb / descent without any control.

Of course, the mechanical design of the platform will be such that its density is very slightly less than the density of the aquatic environment, and compatible with the thrust of the thrusters in an air environment. In both cases, an inertial unit will restore the horizontal attitude of the platform, in the absence of maneuvers made from the control / command station.

An embodiment of the invention will be described below, by way of non-limiting example, with reference to the accompanying drawings in which:

FIGS. 1 and 2 are diagrammatic representations of a mobile platform according to the invention in a marine configuration viewed from above (FIG. 1) and in profile view (FIG. 2), FIGS. 3 and 4 are diagrammatic representations of FIG. the movable platform of FIGS. 1 and 2 in plan view aerial configuration (FIG. 3) and profile view (FIG. 4), FIG. 5 is a cross section of a propulsion unit for the platform of FIGS. 4, in the marine configuration, and FIG. 6 is a cross-section of the thruster of FIG. 5 in an overhead configuration.

In the examples shown in FIGS. 1 to 4, the mobile platform consists of a tubular central beam T and four orientable thrusters P1 to P4 situated on either side of the beam T, namely: two thrusters P1, P3 orientable about a common axis X2, X'2 perpendicular to the longitudinal axis X1, X'1, and two thrusters P2, P4 orientable about a common axis X3, X'3, 10 parallel to the axis X2, X'2, and perpendicular to the longitudinal axis X1, X'1.

The central beam T may contain, at each of its ends, a video camera shooting associated with a lighting headlight, or possibly a night vision camera with image intensifier or an infrared camera; these different cameras will be mounted in a hemispherical transparent bulb BH1, BH2, extending the ends, respectively front and rear, of the central beam T; in the illustrated example, it also comprises an inertial unit for controlling the orientation of the thrusters and the speed of rotation of the propellers concerned so as to maintain the horizontal attitude of the platform in the absence of maneuvers performed from a control / command station not shown. This central beam T may also include sensors intended to transmit information to the control / command station relating to the medium concerned, marine or air; these sensors are advantageously adapted to the medium concerned so as to facilitate the control of the platform.

By way of example, and in a non-exhaustive manner, the sensors intended for the marine environment may be the following: an ultrasound probe, a hydrophone, a bathymetry probe, an underwater navigation beacon, sensors physicochemical (turbidity, salinity, pH, ...).

Similarly, sensors intended for the air environment; may be: - altimeter, - GPS.

And in general, intended for both types of environment: external temperature sensor, artificial horizon, battery voltage meter, laser pointer.

The central beam T is also equipped with an information transmission device between the platform and the control / command station, as described in French patent FR 2 792 478 published on July 13, 2001. This device , not shown, comprises a coil of optical fiber freely rotatable about an axis perpendicular to the longitudinal axis X1, X'1, 20 thus allowing the optical fiber to unfold as and when the advancement of the platform ; this device is advantageously located under the central beam T, preferably in the central position; in addition, said coil comprises a device for converting optical information into electrical information and vice versa; the electrical information is then transmitted to an electronic module, not shown, located in the central beam, via electrical rotary joints, said electronic module providing on the one hand the transmission of the control information to the four thrusters P1, P2 , P3, P4, and on the other hand the transmission of information from the various sensors and in particular the video images.

Advantageously, the aforesaid coil may comprise a sheath of small diameter (approximately 900 μm) comprising three optical fibers, each of which will have a diameter of 250 μm, thus enabling the simultaneous transmission of video images from the front and rear cameras, the artificial horizon, pilot data and data from RS 422 or RS 485 sensors.

In the example illustrated in FIGS. 1 to 4, the four thrusters P1, P3-P2, P4 each comprise a tubular structure respectively TU1, TU3-TU2, TU4, whose main axes A1, A3-A2, A4, respectively pivot about the axes X2, X'2 and X3, X'3, essentially +/- 90 ° on either side of an initial position situated in the plane containing the three aforementioned axes XI, X'1, X2, X'2 and X3, X'3. The axes of the tubular structures fulfill the conditions: A1, A3 perpendicular to X2, X'2 and A2, A4 perpendicular to X3, X'3. These tubular structures TU1, TU3 - TU2, TU4 are integral with supports, respectively SUI, SU3 - SU2, SU4, whose main axes are collinear respectively with the axes X2, X'2 and X3, X'3. These four sets, TU1 / SUI, TU2 / SU2 - TU3 / SU3, TU4 / SU4, constitute the four thrusters PI, P3 - P2, P4; each of them is connected to the central beam T by means of a respective sealed rotary joint located in the respective base, among the four bases EM1, EM3 - EM2, EM4, each base being secured to the central beam T.

Considering that the front of the platform consists of bulb BH1, that is to say that the forward direction of the mobile platform is to the right, the four thrusters PI, P2, P3, P4 are called the following procedure: - P1: port forward thruster PI, - P2: port forward thruster P2, - P3: starboard forward thruster P3, and - P4: rear starboard thruster P4.

In the configuration illustrated in FIGS. 1 and 2, the four thrusters P1, P3-P2, P4 are in the "marine" configuration, the marine propellers, respectively HM1, HM3-HM2, HM4, located at the rear of each thruster, are of the propulsive type. As for the aerial propellers, respectively HA1, HA3-HA2, HA4, located at the front of each thruster, they are represented folded backwards under the effect of a flow of water.

The directions of rotation of the four marine propellers HM1, HM3 - HM2, HM4 will be such that the rotation of the two helices adjacent to the same helix will be of opposite direction; more specifically, the rotation of the forward port and starboard port propellers will be, for example, clockwise; the rotation of the starboard and starboard propellers will therefore be counter-clockwise. Thus, the two port and starboard aft propellers will be propulsive with a right step; the two starboard propellers forward and port side propeller will be propulsive with a step to the left. This configuration of the rotational directions of the propellers thus makes it possible to avoid a rolling effect during the displacement of the platform.

In the configuration illustrated in FIGS. 3 and 4, the four thrusters P1, P3-P2, P4 are in the "overhead" configuration, the marine propellers, respectively HM1, HM3-HM2, HM4, located at the rear of the thrusters, 25 are motionless. As for the air propellers HA1, HA3 - HA2, HA4, located at the front, they are unfolded under the centrifugal effect.

As above, the directions of rotation of the four aerial propellers HA1, HA3-HA2, HA4 are such that the rotation of the two helices adjacent to the same helix are of opposite direction; more specifically, the rotation of the forward port and starboard port propellers are, for example, in the clockwise direction; the rotation of the starboard bow and starboard propellers are therefore counter-clockwise. Thus, the two propellers port forward and starboard rear are tractive with a 5 not left; the two starboard propellers forward and port side are tractive with a step to the right. This configuration of the rotational directions of the propellers thus makes it possible to ensure an almost horizontal plane of lift of the platform.

It can easily be assumed that in the "marine" configuration, the four thrusters P1, P3-P2, P4 respectively pivot about the axes X2, X'2 and X3, X'3, of +/- 90 ° around a initial position in the plane containing the three aforementioned axes X1, X'1, X2, X'2 and X3, X'3.

In the "overhead" configuration, the four thrusters P1, P3-P2, P4 respectively have the axes A1, A3-A2, A4 perpendicular to the plane containing the three aforesaid axes X1, X'1, X2, X'2 and X3. , X'3.

One of the thrusters P1-P4, under the generic reference P, will now be described in greater detail with reference to FIGS. 5 and 6. The thruster P comprises a tubular enclosure TU whose main axis A is the said axis. propulsion; orthogonal to the axis of propulsion A, the axis X, X ', said axis of rotation of the thruster P, is the main axis of a support SU; the tubular enclosure TU and its support SU pivot in the vicinity of a rotary joint JT via a hollow shaft A3, integral with the free end of the support SU, which hollow shaft A3 is rotatably mounted relative to a EM base with two bearings R5, R6; the base EM is integral with the central beam T, not shown. The hollow shaft A3 comprises, in the vicinity of its free end, a pinion PI1, which meshes with a pinion PI2 driving a servomotor SM integral with the base EM.

The tightness of the assembly TU, SU, and EM is provided by a seal J6 in contact with the central beam T, and by a joint J5 of the rotary joint JT; Furthermore, the hollow shaft A3 allows the passage of the electrical conductors connecting the various components contained in the thruster towards the control and control members located in the central beam T. The support SU comprises a power supply battery of the thruster and a VA variator; Furthermore, it comprises a sealed connector, not shown, for recharging the battery.

The tubular enclosure TU comprises a motor MO with double shaft outputs; it is electrically powered by said battery BA through said variator VA, which makes it possible to vary the direction of rotation and the rotational speed of said motor MO.

The motor MO comprises, in the vicinity of each of its shaft ends, the female part EM11, EM21, of two conical clutches, respectively EM1, EM2; these two female parts EM11, EM21 are slidably mounted on the respective shaft outputs of the motor MO via a helical ramp, not shown, allowing, in the direction of rotation of the motor, to be driven in rotation and to slide axially in two opposite directions. Vis-à-vis each of the female parts EM11, EM21, two male parts, respectively, EM12, EM22, integral respectively propeller shafts, respectively Al, A2, are rotatably mounted by means of bearings, respectively R1 , R2, and R3, R4, in the tubular enclosure TU. A marine propulsion propeller HM is secured to the free end of the shaft A1; likewise, an aerial tractive propeller HA is integral with the free end of the shaft A2; the tightness of the shaft Al is provided by two rotating joints J1, J2; likewise, the sealing of the shaft A2 is provided by two rotating joints J3, J4.

Thus, depending on the direction of rotation of the motor MO, it will cause either the marine propulsion propeller HM or the air tractive propeller HA.

In order to improve the efficiency of the marine propulsion propeller HM, a cylindrical casing CA, integral with the tubular enclosure TU, channels the flow of water.

The aerial tractive propeller HA comprises a hub HAc integral with the free end of the shaft A2; this hub comprises two pivot axes of two propeller blades HAa, HAb; thus, these two blades can rotate about an axis, respectively Da, Ab; their stroke respectively is limited firstly by the contact with the tubular enclosure TU, and secondly by a stop located in the propeller hub HAc, not shown. Thus, in the absence of rotation of the shaft A2, especially under the effect of a flow of water, the blades of propellers HAa, HAb, will be folded, in contact with the tubular chamber TU; in case of rotation of the A2 tree, these will be deployed and become tractive.

In FIG. 5, the thruster P is in the so-called "marine" configuration; in Figure 6, the thruster P is in the so-called "air" configuration.

The mechanical design of the platform according to the invention is such that its density is between 1 and 0.8 times, and preferably between 0.998 and 0.996 times, the density of the aquatic medium. Likewise, the mechanical design of the platform according to the invention is such that its mass is between 1 and 0.5 times, and preferably between 0.8 times and 0.5 times. , the thrust of thrusters P1 to P4 in the air.

The piloting of the mobile platform, according to the invention, will be such that a strong analogy between the two modes known as "marine" and "aerial" will make it possible to exploit the same controls from two "right-hand" pedals and "Left hand", each having two degrees of freedom along the horizontal axes longitudinal OX and transverse OY. The rudder "right hand" will be devoted to throttle control and change of course; the "left hand" rudder will devolve to the modification of the platform attitude.

The choice of mode, "marine" or "overhead", will be made from a simple two-position switch; Of course, the choice of mode, "marine" or "air", will affect several factors that affect the operation of each of the four propellers.

Thus, taking into account the actions carried out by means of the two "right-hand" and "left-hand" pedals and the "sea" or "air-mode" selection switch, the control of the mobile platform, according to the The invention is similar to that of a rotary wing, knowing that it can evolve in a medium such as water and air indifferently along three orthonormal longitudinal axes Ox, transverse Oy and vertical Oz .

More precisely, the switch "marine configuration / aerial configuration", or more simply said the "water / air" switch intervenes at three levels: - on the main orientation of the thrusters, on the direction of rotation of the four electric motors, 10 2974760 - 14- on the "left hand" rudder controls.

Regarding the main orientation of the thrusters: in the "marine" configuration, the four thrusters P1, P3-P2, P4, 5 respectively pivot about the X2, X'2 and X3, X'3 axes, of +/- 90 ° around an initial position situated in the plane containing the three aforementioned axes X1, X'1, X2, X'2 and X3, X'3,

in the "overhead" configuration, the four thrusters P1, P3-P2, P4 respectively have the axes A1, A3-A2, A4, perpendicular to the plane containing the three aforementioned axes X1, X'1, X2, X'2 and X3, X'3.

As regards the direction of rotation of the four electric motors, it will be in one direction in the "marine" configuration and in the opposite direction in the "overhead" configuration, so that, depending on the direction of rotation of the engine, the latter respectively drives either the marine propulsion propeller HM, the aerial tractive propeller HA. In addition, the direction of rotation of the four engines is such that: in the "marine" configuration: 20 - the marine propeller propellers port forward starboard and starboard turn clockwise, and - the propeller propellers marine port side and starboard front turn in counter clockwise; in "overhead" configuration: 25 - the aerial propellers on the port bow and starboard side turn clockwise, and - the aerial propellers on the port and starboard bow forward rotate counterclockwise. It should be noted that the direction of rotation of the engine is effectively reversed in the "marine" or "overhead" configuration, since the directions of rotation of the marine or overhead propellers are seen respectively on the rear side or on the front side of the engine. .

Concerning the "left hand" rudder controls, they will be such that: in "marine" configuration: according to the OX and OY axes, they will act on the orientation of each of the four thrusters, in the "overhead" configuration: axes OX and OY, they will act on the rotational speeds of each of the four engines.

The rudder "right hand" is devolved to the throttle and the change of course as follows: 15 along the axis OY: this command can vary the rotation speed Ç2 of the four engines from S2 = 0 to £ 2 = umax, according to the directions described above; the corresponding names, depending on the configurations, are as follows: 20 - in the "marine" configuration: thrust, - in the "overhead" configuration fixed wing: throttle, - in the "overhead" configuration rotary wing: not general (nick) . Of course, the rotational speeds of the four motors will be equivalent at all times. along the axis OX: this command makes it possible to vary the orientation of the platform to the right or to the left, the attitude being horizontal; the corresponding names, according to the configurations, are the following: - in "marine" configuration: heading, 2974760 - 16- - in "aerial" configuration fixed wing: rudder beam, - in "aerial" configuration rotary wing: yaw (twist).

More precisely: 5 - in "marine" configuration: / heading to starboard: port and port forward engines: S2> 0 starboard engines front and rear stern: S2 = 0 / port cap: 10 port and port engines port side: S2 = 0, starboard forward and starboard engines: S2> 0.

- in "overhead" configuration: / starboard tack: 15 S2 (port and starboard engines)> S2 (port and starboard forward engines), / port to port: S2 (port and starboard engines) <£ 2 (port and starboard engines forward). The "left hand" rudder is devoted to modifying the attitude of the platform in the following manner: along the axis OY: this command makes it possible to vary the incidence of the platform 25 in a plane vertical containing the main axis of said platform; the corresponding names, according to the configurations, are as follows: - in "marine" configuration: depth, - in "air" configuration fixed wing: elevator, 30 - in "aerial" configuration rotary wing: pitch (pitch). 2974760 - 17 - In a more precise way: - in "marine" configuration: / diving: forward port thrusters, port starboard, starboard 5 forward and aft starboard: a <0, / lift: forward port thrusters orientation, port side, starboard front and starboard rear: a> 0.

10 - in "overhead" configuration: / down: Q (front port and starboard engines forward) <£ 2 (rear port and starboard engines), / up: 15 0 (front port and starboard engines)> Q (port and starboard rear engines).

along the axis OX: this command makes it possible to vary the incidence of the platform 20 in a vertical plane perpendicular to the main axis of said platform; the corresponding names, according to the configurations, are as follows: - in "marine" configuration: heel, - in "air" configuration fixed wing: aileron (ailvator), 25 - in "aerial" configuration rotary wing: roll (roll).

In a more precise way: - in "marine" configuration: / list to starboard: 30 orientation of the forward port thrusters, port sideboard: a> 0; orientation of starboard forward and aft starboard thrusters: a <0, -18- / port tack: forward port thruster orientation, aft port side: a <0; orientation of the starboard bow thrusters: a> 0.

- in "overhead" configuration: / starboard tack: S2 (port forward and port port engines)> S2 (starboard forward and aft starboard engines), / port list: S2 (port forward and port port side engines) <S2 (engines starboard bow and starboard aft).

Thus, thanks to the actions performed by means of the two pedals 15 "right hand" and "left hand", the piloting of the mobile platform, according to the invention, is similar to that of a rotary wing, knowing that it can evolve indifferently according to the three orthonormal axes Ox, Oy and Oz; only the water / air mode switch determines the choice of medium such as water or air. Two transitions of water / air medium are conceivable as follows: to effect the air / water transition, the platform evolving in an air environment, approaches the vertical of the surface of the water until natural flotation then, thanks to the air / water commutation, the direction of rotation of the engines are reversed, driving the marine propellers, the propellers are oriented in diving incidence, the aerial propellers fold back under the effect of the flow of water; the platform evolves in the marine environment. To effect the water / air transition, the platform operating in the marine environment approaches the vertical surface of the water until it is placed in natural flotation and, thanks to the water / air switching, the propellers 10 The direction of rotation of the engines reverses, causing the aerial propellers unfolding under the centrifugal effect, the marine propellers being immobile; the platform rises from the surface of the water and evolves in an air environment. Thus, it can be seen that according to the air / water or water / air transition, the sequences of reversal of the direction of rotation of the motors and orientation of the thrusters are different.

During the air-to-water transition, from a stationary state, only the throttle control (right-hand rudder, according to OY) will be required to approach the water surface vertically up to natural floatation.

As for the water / air transition, the throttle control ("right hand" rudder, according to OY) and the control of the propeller thrust ("left hand" rudder, according to OY) will be necessary to make a vertical approach from the surface of the water to natural flotation.

Of course, the platform, according to the invention, is adapted to pose, as a rotary wing, on the ground or on the deck of a building surface. 5

Claims (6)

REVENDICATIONS1. Mobile platform intended to be remotely controlled, characterized in that it comprises two pairs of thrusters (P1, P2, P3, P4) having respective propulsion axes (A1, A2, A3, A4) orientable in two parallel planes between them and to a longitudinal axis (X1, X'1) of the platform, each thruster comprising a propellant marine propeller (HM1, HM2; HM3, HM4) and a tractive air propeller (HA1, HA2, HA3, HA4) respectively each thruster further comprising an electric motor (M1, M2 - M3, M4) for driving in rotation either the marine helix or the overhead propeller, the platform further comprising means for switching a coupling between said engine and the engine. one or the other of the marine and air propellers, said switching means comprising means for reversing the direction of rotation of said electric motor. 2. Platform according to claim 1, characterized in that each thruster (P1-P4) of a pair has a common axis of rotation (X2, X'2; X3, X'3) with a thruster of the other pair. 20 3. Platform according to claim 1, characterized in that it is adapted to evolve in an aquatic environment, and in that the aforesaid propellants (P1, P2, P3, P4) comprise means for generating a stream of water. serving to propel the aforesaid platform. 4. Platform according to claim 1, characterized in that it is able to evolve in an air environment, and in that the above-mentioned thrusters (P1, P2-P3, P4) comprise means for generating a flow of air used to ensure the sustenance of the aforesaid platform. 2974760 - 21 - 5. Platform according to claim 3, characterized in that its density is between 1 time and 0.8 times, and preferably between 0.998 times and 0.996 times, the density of the aquatic environment. 5 6. Platform according to claim 4, characterized in that its mass is between 1 time and 0.5 times, and preferably between 0.8 times and 0.5 times, the thrust of the thrusters (P1, P2- P3, P4) in the air.