OPERATOR TERMINAL OF AN AIRCRAFT SYSTEM FOR STEERING AN AIRCRAFT

Description

[0001] The present invention relates to an operator terminal of an aircraft piloting avionics system and an associated information display method, within the framework of complex missions.

[0002] The invention lies in the field of aircraft piloting safety, and finds particular application in the field of flight control and guidance systems for an aircraft performing a mission.

[0003] The term aircraft generally refers to any platform adapted to fly, with a pilot on board or remotely controlled, without a pilot on board, for example an airplane, a helicopter or a drone.

[0004] An aircraft mission can be military, within the framework of tactical operations, or civilian, for example, a supply mission or a search and rescue mission at sea. Unlike a planned flight for a commercial airliner, where piloting is guided by an avionics system to follow a pre-calculated trajectory, the missions assigned to aircraft that may incorporate the invention consist of a sequence of task phases of various kinds.

[0005] For each phase of the mission, the crew uses different types of environmental information. The term "crew" here refers to the person or persons responsible for piloting the aircraft.

[0006] Currently, various systems known as mission systems exist, which interact with a flight management system (FMS). These mission systems use information from onboard sensors and provide the FMS with the constraints it needs to calculate an optimal trajectory for the crew or autopilot system. Such mission systems are highly complex and use a vast amount of information, and the crew is not informed of the details of the calculations performed. Consequently, it is difficult for the pilot to know the factors that led to the trajectory calculation and to understand its construction. As a result, the pilot cannot assess the margin of error available to maintain the proposed trajectory.

[0007] Other mission systems allow for the display of a great deal of information, but such displays are very cluttered and complex to interpret, whereas during a mission flight, the crew must make decisions very quickly. An overloaded display increases the mental workload of the pilot(s) and does not promote safe flight operations.

[0008] Patent application WO 2008 / 065120 A1 describes a visualization device for understanding the aerial environment of an aircraft, comprising a display of coloured areas corresponding to levels of danger to the aircraft.

[0009] Patent application EP 1 245 929 A2 describes an aircraft piloting assistance device comprising a presentation of information on a display screen.

[0010] There is a need to improve mission control information systems to help improve the acceptability of data from complex processing in avionics systems, and to enhance security and the anticipation of risks by the crew.

[0011] To this end, the invention proposes, according to a first aspect, an operator terminal for an avionics system for piloting an aircraft according to claim 1.

[0012] The operator terminal according to the invention may have one or more of the features of dependent claims 2 to 6, taken independently or in combination, according to all technically acceptable combinations.

[0013] According to another aspect, the invention relates to an avionics system for piloting an aircraft adapted for use during a mission according to claim 7.

[0014] According to another aspect, the invention relates to a display method implemented by an operator terminal of an aircraft piloting avionics system according to claim 8.

[0015] According to one embodiment, the display method comprises one or more of the features of dependent claims 9 to 11.

[0016] Other features and advantages of the invention will become apparent from the description given below, by way of example and not limitation, with reference to the attached figures, including: there figure 1 is a schematic view of an avionics system according to one embodiment of the invention; the figure 2 is a schematic illustration of a display view according to a first display mode; the figure 3 is a schematic illustration of a display view according to a second display mode; the figure 4 is a flowchart of the main steps of a display process according to a particular embodiment.

[0017] The invention will be described in an embodiment of an avionics system for displaying flight information of an aircraft, comprising an operator terminal on board the aircraft.

[0018] Alternatively, the avionics system is distributed between the aircraft and the ground, and the operator terminal is in a ground command center.

[0019] An example of avionics system 1 according to the invention is illustrated in the figure 1 .

[0020] This avionics system 1 allows for improved mission piloting of an aircraft not shown.

[0021] System 1 comprises a plurality 2 of sensors 2a, 2b, 2c mounted on the aircraft. These sensors include, for example, radio altimeters, image sensors in various spectral bands (visible, near-infrared, etc.), radio sensors, and surveillance or combat radars equipped with imaging or weather modes. It is understood that sensors 2a, 2b, and 2c are represented only as examples, and that any number of sensors may be used.

[0022] These sensors are adapted to transmit data relating to the aircraft's environment at the time the flight is carried out, to a mission system 4, and, as an optional complement, directly to an operator terminal 6 via a communication module 8 of that operator terminal.

[0023] In this example, the operator of this terminal is the pilot of the aircraft.

[0024] The communication module 8 is, for example, a wired communication module, and in this case the data transmitted by the sensors 2 are transmitted via this wired link, according to an appropriate communication protocol.

[0025] Alternatively, communication module 8 is adapted to communicate according to a radio communication protocol, possibly secured by encryption processes.

[0026] System 1 also includes a flight management system or FMS 5, which cooperates with the mission system 4 and generates a reference trajectory for the aircraft, denoted T Ref, based in particular on information provided by sensors 2.

[0027] In addition, supplementary information 9, transmitted by means of radio communication from a command center or another unit (regardless of its location: airborne, on the ground, on the surface...) is also received and used.

[0028] The operator terminal 6 can either be mounted on board the carrier or located in a ground control center. It comprises a central processing unit 10, or CPU, for example an electronic processor, capable of executing computer program instructions when the terminal 6 is powered on, one or more display modules 12, and a human-machine interface (HMI) 14 for inputting operator commands, which is, for example, a touchscreen command input module. Alternatively, the command input interface 14 is integrated with a touchscreen display 12.

[0029] It also includes an electronic memory unit 16 suitable for storing data and executable code instructions.

[0030] Functional blocks 8, 10, 12, 14 and 16 are interconnected, for example via a communication bus.

[0031] A mission plan comprising several mission phases is generally prepared before the mission, and is received by the mission system 4 either via a data link or via a file transfer method (such as a memory card or even a USB key).

[0032] The operator terminal 6 is adapted to receive mission commands 18, via the command input interface 14. For example, commands 18 allow an operator, the aircraft pilot, to make tactical choices or to initiate a mission type or a change of mission phase.

[0033] A tactical choice, for example, corresponds to choosing an alternative from several system options (avoiding or engaging a threat, for example, or choosing a trajectory from options corresponding to different pilot profiles). A change of mission phase can occur automatically, for example, when the aircraft reaches a predefined point, or at the pilot's command. For example, if the current mission phase is to search for a vessel in distress, the pilot can request a change of mission phase once the vessel has been located.

[0034] A mission plan comprises several phases, which are chosen, for example, by the operator from a set of predetermined phases.

[0035] For example, several phases can be distinguished: A) Transit phase, during which the aircraft moves between point A and point B; B) Search and observation phase, during which the aircraft observes a search area, to be traversed according to a given flight pattern; C) Hover phase, during which the aircraft must position itself above a target area and maintain the current position; D) Cargo drop phase, during which an appropriate drop zone must be determined and the aircraft must be maintained in that position.

[0036] Of course, the list of mission phases A), B), C) D) given above is not exhaustive.

[0037] Each mission phase corresponds to a specific objective, and therefore different flight constraints may apply depending on the type of mission phase currently underway.

[0038] In an advantageous embodiment, the type of aircraft trajectory display on a display module 12 of the operator terminal 6 is selected according to the mission phase, as explained in detail below. Thus, the most suitable display with respect to the objectives of the mission phase and the associated constraints is chosen.

[0039] In the illustrated embodiment, the operator terminal 6 is connected to an aircraft control device 20. This control device 20 is adapted to receive guidance instructions from the operator terminal 6 and to apply them, in a known manner, to modify the aircraft's trajectory, according to accessibility zones defined based on constraints associated with the mission phases.

[0040] In particular, the operator terminal according to the invention is adapted to warn the pilot (for example by lifting an alert) if there is a risk deemed significant that one of the constraints associated with the current mission phase will not be respected.

[0041] The control device 20 incorporates, in one embodiment, an automatic control device.

[0042] There figure 2 schematically illustrates a display window 30 of a display module 12 of the operator terminal 6.

[0043] In this window 30 is displayed, in a first display mode which is the vertical display mode, in top view of the terrain flown over, the reference trajectory T Ref of the aircraft provided by the FMS 5.

[0044] The display includes a first graphic symbol 32, which is an arrow in this example, indicating the current POS position of the piloted aircraft and the direction of flight of the aircraft.

[0045] In addition, the display optionally includes, depending on the situation, a second graphic symbol 34, which is also an arrow in this example, indicating the current position POS_E of a second aircraft, an escorting crew member of the piloted aircraft, and the flight direction of this second aircraft. If applicable, the positions of several escorting aircraft are displayed.

[0046] Several accessibility zones Z0, Z1, Z2, Z3, and Z4 are displayed. The reference trajectory TRef intersects at least one of these zones, with the remaining zones located ahead of the aircraft's current position and contained within the area (the extent of which is adjustable by the operator) to which the pilot is focused. Several zones are represented, corresponding to areas where various types of constraints apply in the vicinity of the aircraft's current altitude, near the reference trajectory and the aircraft's current position (for example, areas where the terrain is close to the aircraft's current flight level or within range of known enemy weapon systems).

[0047] The accessibility areas displayed are two-dimensional areas in this first display mode, but correspond to three-dimensional areas.

[0048] By spatial proximity, we mean here that the distance considered is less than the uncertainty of relative positioning of the two elements considered.

[0049] The accessibility level is chosen from a predefined set of accessibility levels, at least equal to 2: accessible and inaccessible.

[0050] The accessibility level of an accessible area is higher than the accessibility level of an inaccessible area.

[0051] Alternatively, several levels of accessibility, including intermediate accessibility levels, are also defined.

[0052] For example, accessible areas are areas where the distance to any obstacle (terrain or otherwise) is considered sufficient, there is no significant turbulence, and no other significant hazards related to the current mission phase have been detected.

[0053] For example, inaccessible areas are areas of obstruction (terrain or risk of collision with another aircraft), areas of meteorological turbulence that prevent the proper functioning of onboard instruments.

[0054] The level of accessibility is calculated from constraints associated with the mission phase, the calculation being carried out according to the mission phase.

[0055] Of course, the display is dynamically updated at regular time intervals, for example every 40 ms, which allows it to take into account the aircraft environment, the operator's commands and a possible change in mission phase.

[0056] Accessibility zones have a visual characteristic, such as a pattern or color, related to the accessibility level. For example, each predetermined accessibility level has an associated color, allowing the operator to easily distinguish accessible areas from prohibited areas.

[0057] There figure 3 schematically illustrates a display window 40 of a display module 12 of the operator terminal 6.

[0058] The display of the figure 3 is a second display mode adapted in particular for a search and observation phase (phase B) according to a given path pattern.

[0059] The display includes a sub-window 42 which indicates the search perimeter to be flown over, and a first graphic symbol 44, which is an arrow in this example, indicating the current POS position of the piloted aircraft and the direction of flight of the aircraft.

[0060] The search perimeter 42 is divided into portions 46 to be observed, and the portion or portions 48 already verified are also displayed with a chosen display pattern.

[0061] In addition, we also display, with a chosen display pattern, zone 47 during the journey and which is located within the capture perimeter of the onboard sensors 2.

[0062] Thus, the operator has a very clear view of the portion of the search area already covered and the portions remaining to be covered, and therefore has all the elements necessary for conducting the flight in the short term.

[0063] In addition, superimposed on the display window 40 are the accessibility zones Z 0 , Z 4, which are respectively in this example an accessible zone Z 0 and an inaccessible zone Z 4.

[0064] Similarly, in the method of implementation of the figure 2 The displayed accessibility areas have a visual characteristic, for example pattern or color, related to the level of accessibility.

[0065] There figure 4 is a flowchart of the main steps of a display method for mission piloting assistance of an aircraft according to an embodiment of the invention.

[0066] A first step, 50, is implemented to obtain the mission plan and the current mission phase. For example, the operator indicates the mission type and the current mission phase via the human-machine interface. Alternatively, after the mission type is indicated, the current mission phase is automatically updated, as each mission type has a sequence of associated mission phases (mission plan) that is previously recorded.

[0067] Environmental data is obtained in step 52, "Environmental Data Acquisition." This environmental data includes data provided by onboard sensors, notably the aircraft's position in a geolocation reference system, and data provided by navigation instruments, particularly data relating to the aircraft's current dynamics, including vertical speed, vertical acceleration, current airspeed, and heading. Onboard sensors also provide information (or parameters) about the environment, particularly regarding other units present in the area of ​​operations. Of course, other parameters measured for aircraft piloting assistance are also usable.

[0068] In addition, information received from a ground control center and useful for piloting complements the environmental data, for example information relating to other aircraft located nearby.

[0069] These parameters are, as is known, provided to the mission system, which extracts the constraints applicable to flight control (based on the progress of the mission plan and the state of the onboard systems). The FMS uses these constraints to calculate a reference trajectory T Ref for the aircraft, obtained in step 54.

[0070] In the next step 56, a three-dimensional envelope Env_AR of a short-term predicted trajectory is determined, based on the state (position and dynamics) of the aircraft, the reference trajectory T Ref, the data relating to the current dynamics and the state of the controls.

[0071] Here, aircraft dynamics refers to its velocity and acceleration vector characteristics.

[0072] Indeed, when the autopilot is not used and the pilot flies manually, or when external elements (especially wind) cause the aircraft to deviate, the latter does not exactly follow the reference trajectory T Ref calculated by the FMS.

[0073] The three-dimensional envelope Env_AR is a volume surrounding the calculated predicted trajectory, in which the aircraft is considered to have a significant probability of evolving (this level of probability corresponds to the acceptable non-detection rate of dangerous situations within the mission).

[0074] This envelope Env_AR is discretized at step 56, for example it is modeled by a set of nodes N i , each node N i being defined by a triplet (X i , Y i , Z i ) of coordinates in a three-dimensional spatial reference frame.

[0075] For each node Ni, we then obtain in step 58 a set of associated applicable constraints. The applicable constraints fall into two categories: imperative constraints, applicable in an absolute and binary way: they are characterized by areas that are absolutely inaccessible in a given mission context; relative constraints, the importance of which is assessed according to the current mission phase and other applicable constraints, for example the detection volumes of known enemy sensors.

[0076] In the category of imperative constraints, there are, for example, obstacle avoidance constraints, for example, depending on the terrain (relief, buildings) or depending on the presence of other aircraft.

[0077] In the category of relative constraints, there is, for example, the presence of meteorological turbulence: a given localized type of turbulence may have more impact in a hovering or cargo drop phase than in a transit phase.

[0078] Some constraints may only be taken into account for certain mission phases. Alternatively, all relevant constraints are taken into account at each mission phase, but with an associated weighting coefficient, which may be equal to zero for some mission phases.

[0079] For example, each node N i is associated with a constraint vector, whose values ​​are calculated based on the information received.

[0080] The constraints associated with a node are calculated based on the spatial position of the node relative to an area, for example, altitude relative to the terrain, position relative to a cloud zone, or situation relative to an estimated sphere of danger from an enemy unit.

[0081] In step 60, a synthetic value is then calculated for the various constraints applicable to the same node, for example using a weighted sum. This synthetic value represents the level of accessibility (or, conversely, danger) associated with the geographical position corresponding to the node in question.

[0082] In addition, accessibility zones with the same level of accessibility are calculated.

[0083] The level of the various constraints applicable around the position of the aircraft and the reference trajectory are displayed during a display step 64, superimposed on the reference trajectory.

[0084] Optionally, step 62 consists of determining the most appropriate display mode for the current task and the nature of the surrounding constraints.

[0085] For example, if the current task is to navigate in formation, the system will display a top-down view showing the position of the formation members and the reference trajectory. Conversely, if the aircraft needs to search for a vessel in an area, the system will display the search area, the areas in which the search has already been conducted, and a set of trajectory segments that allow the flight to perform the search optimally. In both cases, the system will also represent the various external constraints that could influence flight operations, as described previously.

[0086] On the other hand, the system alerts the pilot (step 66) when it becomes likely that one of the mission constraints will not be respected: if the envelope around the predicted trajectory contains a node whose synthetic accessibility level is too low, therefore below a predetermined threshold, or a node where an imperative constraint is active (for example: the corresponding geographical position is below ground level), then the pilot is alerted and the constraint or the problematic area is characterized on the system's display module by information intended for the pilot.

[0087] Preferably, the alert is displayed on the screen in a way that immediately draws the operator's attention, for example, by flashing a light. In addition, an audible alert is also triggered.

[0088] The operator can then perform avoidance maneuvers, and thanks to the display of indications, he has information to make tactical choices.

Claims

1. An operator terminal of an avionic system for flying an aircraft, suitable for use during a mission defined by a mission plan including a plurality of mission phases, each mission phase corresponding to at least one task to perform, the operator terminal (6) comprising at least a display module (12) and a computing device (10), implementing a flight management system suitable for determining a reference trajectory (TRef) of said aircraft by incorporating at least one environment constraint, adapted to display on said display module (12) a current position of the aircraft, characterized in that is suitable for displaying on said display module (12) : said reference trajectory (TRef), and a plurality of accessibility zones (Z0, Z1, Z2, Z3, Z4), at least one of said accessibility zones having an intersection with said reference trajectory, said accessibility zones having an associated accessibility level, between at least two accessibility levels so as to define accessible zones and non-accessible zones for a current mission phase, the accessibility zones having a visual characteristic linked with the accessibility level, the accessibility level being defined as a function of the current mission phase, a trajectory predicted from the reference trajectory and at least two flight constraints associated with the current mission phase, said constraints associated with the current mission phase comprising at least one mandatory constraint and at least one relative constraint associated with the current mission phase.

2. The operator terminal according to claim 1, characterized in that the display is done according to a display mode chosen according to a first display mode and a second display mode based on the current mission phase.

3. The operator terminal according to claim 1 or 2, characterized in that each accessibility zone (Z0, Z1, Z2, Z3, Z4) has an associated display characteristic representative of the accessibility level.

4. The operator terminal according to one of claims 1 to 3, characterized in that the display also includes a first graphic symbol (32), indicating a current position of the flown aircraft and a direction of flight of the aircraft, and at least one second graphic symbol (34), indicating a position of a second aircraft.

5. The operator terminal according to one of claims 1 to 4, characterized in that the display includes an alert display when the predicted trajectory crosses a zone with an accessibility level below a predetermined threshold.

6. The operator terminal according to one of claims 1 to 5, characterized in that the display is refreshed dynamically at regular time intervals.

7. An avionic system for flying an aircraft suitable for use during a mission including a plurality of mission phases, the avionic system including an operator terminal (6) connected to a device (20) for flying the aircraft, characterized in that said operator terminal is according to one of claims 1 to 6.

8. A display method implemented by an operator terminal of an avionic system for flying an aircraft, suitable for use during a mission defined by a mission plan including a plurality of mission phases, each mission phase corresponding to at least one task to perform, the operator terminal comprising at least a display module and a computing device, implementing a flight management system suitable for determining a reference trajectory of said aircraft by incorporating at least one environment constraint, characterized in that it includes the following steps: - computing (56) a predicted trajectory of the aircraft as a function of said reference trajectory, computing a plurality of accessibility zones, at least one of said accessibility zones having an intersection with said reference trajectory, said accessibility zones having an associated accessibility level, between at least two accessibility levels so as to define accessible zones and non-accessible zones for a current mission phase, the accessibility zones having a visual characteristic linked with the accessibility level, the accessibility level being defined as a function of the current mission phase and at least two flight constraints associated with the current mission phase, said constraints associated with the current mission phase comprising at least one mandatory constraint and at least one relative constraint associated with the current mission phase, - displaying (64), on a module of the operator terminal, the reference trajectory, a current position of the aircraft and said accessibility zones.

9. The method according to claim 8, wherein the calculation of accessibility zones comprises the following steps: - computing (56) a three-dimensional envelope of the predicted trajectory, and obtaining a plurality of nodes representative of said envelope, - for each node, obtaining (58) a plurality of associated constraints, as a function of the current mission phase, and calculating (60) an accessibility level by a sum weighted by weight coefficients associated with said constraints, at least part of the weight coefficients depending on the current mission phase.

10. The method according to claim 9, further including a step for emitting an alert (66) if said envelope contains a node whose calculated accessibility level is below a predetermined threshold.

11. The method according to claim 10, wherein the alert emission (66) includes a display on the display module of an alert indicator and of information relative to at least one constraint applicable to said node.