Aircraft having at least one control device for controlling inflation of an inflatable safety bag, and an associated method of controlling inflation of an inflatable safety bag

Abstract

A control device including at least one control member for measuring an acceleration of an aircraft, for generating an inflation order, and for transmitting the inflation order to an inflation member, the inflation member serving to inflate at least one inflatable safety bag, the control device, the inflation member and the inflatable bag being arranged together on a single seat of the aircraft. Such a control device includes at least one readying system connected to the at least one control member, the readying system comprising: at least a first sensor suitable for continuously measuring a first current acceleration of the aircraft relative to at least one axis; and at least one switch that is controllable as a function of the first current acceleration of the aircraft as measured by the first sensor.

Claims

1. An aircraft having at least one control device with at least one control member for measuring an acceleration of the aircraft, for generating an inflation order, and for transmitting the inflation order to an inflation member, the inflation member serving to inflate at least one inflatable safety bag, the control device together with the inflation member and the inflatable safety bag being arranged together on a single seat of the aircraft, the control device including at least one readying system connected to the at least one control member, the at least one readying system comprising: at least one first sensor continuously measuring a first current acceleration (A.sub.C1) of the aircraft relative to at least one axis (X, Y, Z), the at least one control member providing a measurement of the acceleration of the aircraft that is independent of the first current acceleration (A.sub.C1) of the aircraft as measured by the first sensor; and at least one controllable switch that is controllable as a function of the first current acceleration (A.sub.C1) of the aircraft as measured by the first sensor, the controllable switch serving to activate and deactivate at least one control member by electrically connecting and disconnecting a source of electricity to the control member, the control member including at least one second sensor suitable for measuring, at least temporarily, a second current acceleration (A.sub.C2) of the aircraft relative to at least one axis; wherein the control member includes at least one computer for comparing the absolute value of the second current acceleration (A.sub.C2) of the aircraft with a third acceleration threshold (S.sub.3) and for causing the controllable switch to open in order to disconnect the source of electricity from the control member when the absolute value of the second current acceleration (A.sub.C2) of the aircraft is less than the third acceleration threshold (S.sub.3) for a predetermined number of comparison iterations (I.sub.1) performed by the at least one computer between the absolute value of the second current acceleration (A.sub.C2) of the aircraft and the third acceleration threshold (S.sub.3).

2. The aircraft according to claim 1, wherein the controllable switch connects a source of electricity to the control member when the absolute value of the first current acceleration (A.sub.C1) of the aircraft becomes greater than a first acceleration threshold (S.sub.1).

3. The aircraft according to claim 2, wherein the at least one readying system includes damper means for damping the first current acceleration (A.sub.C1) of the aircraft as measured by the first sensor, the damper means serving to filter a measurement (V.sub.1) of the first current acceleration (A.sub.C1) of the aircraft, the controllable switch connecting the source of electricity to the control member when the measurement (V.sub.1) of the first current acceleration (A.sub.C1) of the aircraft is greater in absolute value than the first acceleration threshold (S.sub.1).

4. The aircraft according to claim 1, wherein the controllable switch disconnects the source of electricity from the control member when the absolute value of the first current acceleration (A.sub.C1) of the aircraft is less than a second acceleration threshold (S.sub.2) for a predetermined duration (T.sub.1).

5. The aircraft according to claim 1, wherein the at least one computer compares the absolute value of the second current acceleration (A.sub.C2) of the aircraft with a fourth acceleration threshold (S.sub.4) and compares the mean value (A.sub.C2M) of the second current acceleration (A.sub.C2) of the aircraft over a predetermined time interval with a fifth acceleration threshold (S.sub.5), the computer generates the inflation order and then transfers the inflation order to the inflation member when, firstly, the absolute value of the second current acceleration (A.sub.C2) of the aircraft is greater than the fourth acceleration threshold (S.sub.4), and, secondly, the mean value (A.sub.C2M) of the second current acceleration (A.sub.C2) of the aircraft over the predetermined time interval is greater than the fifth acceleration threshold (S.sub.5).

6. The aircraft according to claim 5, wherein the control member includes at least one memory serving to store at least data representative of the third, fourth and fifth acceleration thresholds (S.sub.3, S.sub.4, S.sub.5).

7. The aircraft according to claim 1, wherein the at least one first sensor is formed by a mechanical sensor suitable for measuring an acceleration relative to at least one axis.

8. The aircraft according to claim 1, wherein the at least one first sensor and the at least one second sensor are selected from the group consisting of micro-electromechanical systems (MEMS) and nano-electromechanical systems (NEMS) suitable for measuring acceleration relative to at least one axis (X, Y, Z).

9. The aircraft according to claim 5 wherein the at least one second sensor is saturated so as to measure an acceleration relative to at least one axis (X, Y, Z) solely below a sixth acceleration threshold (S.sub.6) that is selected to be greater than or equal to the fourth acceleration threshold (S.sub.4).

10. A control method for controlling inflation of at least one inflatable safety bag arranged on an aircraft seat in an aircraft, the control method including at least a measurement step consisting of measuring an acceleration of the aircraft and a step of generating an inflation order and of transmitting the inflation order to an inflation member enabling the at least one inflatable safety bag to be inflated, the control method comprising: a preliminary measurement step performed by at least one first sensor, the preliminary measurement step consisting in continuously measuring a first current acceleration (A.sub.C1) of the aircraft relative to at least one axis (X, Y, Z), the measurement step providing a measurement of the acceleration of the aircraft independent of the first current acceleration (A.sub.C1) of the aircraft; and an activation step and a deactivation step for activating and deactivating a control member enabling the step to be performed that consists of generating an inflation order and in transmitting the inflation order to the inflation member for inflating the at least one inflatable safety bag, the activation step and the deactivation step being performed by electrically connecting and disconnecting a source of electricity relative to the control member; the measurement step being performed via the control member and serving, at least temporarily, to measure a second current acceleration (A.sub.C2) of the aircraft relative to at least one axis, wherein the absolute value of the second current acceleration (A.sub.C2) of the aircraft is compared with a third acceleration threshold (S.sub.3) ands a controllable switch is caused to open so as to disconnect the source of electricity from the control member when the absolute value of the second current acceleration (A.sub.C2) of the aircraft is less than the third acceleration threshold (S.sub.3) for a predetermined number of comparison iterations (I.sub.1) between the absolute value of the second current acceleration (A.sub.C2) of the aircraft and the third acceleration threshold (S.sub.3).

11. The method according to claim 10, wherein the absolute value of the first current acceleration (A.sub.C1) of the aircraft is compared with a first acceleration threshold (S.sub.1), and the source of electricity is connected to the control member when the absolute value of the first current acceleration (A.sub.C1) of the aircraft is greater than the first acceleration threshold (S.sub.1).

12. The method according to claim 10, wherein a measurement (V.sub.1) of the first current acceleration (A.sub.C1) of the aircraft is filtered, the measurement (V.sub.1) is compared with a first acceleration threshold (S.sub.1), and the source of electricity is connected to the control member when the measurement (V.sub.1) is greater, in absolute value, than the first acceleration threshold (S.sub.1).

13. The method according to claim 10, wherein the source of electricity is disconnected from the control member when the absolute value of the first current acceleration (A.sub.C1) of the aircraft is less than a second acceleration threshold (S.sub.2) during a predetermined duration (T.sub.1).

14. The method according to claim 10, wherein the absolute value of the second current acceleration (A.sub.C2) of the aircraft is compared with a fourth acceleration threshold (S.sub.4) and the mean value (A.sub.C2M) of the second current acceleration (A.sub.C2) of the aircraft over a predetermined time interval is compared with a fifth acceleration threshold (S.sub.5), the inflation order is generated and the inflation order is then transferred to the inflation member when, firstly, the absolute value of the second current acceleration (A.sub.C2) of the aircraft is greater than the fourth acceleration threshold (S.sub.4) and, secondly, the mean value (A.sub.C2M) of the second current acceleration (A.sub.C2) of the aircraft over the predetermined time interval is greater than the fifth acceleration threshold (S.sub.5).

15. The method according to claim 14, wherein the method includes a step of storing in at least one memory data that is representative of the third, fourth and fifth acceleration thresholds (S.sub.3, S.sub.4, S.sub.5), the at least one memory forming an integral portion of the control member.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

(1) The invention and its advantages appear in greater detail from the context of the following description of examples given by way of illustration with reference to the accompanying figures, in which:

(2) FIGS. 1 to 3 are structural diagrams showing three variants of devices in accordance with the invention for controlling the inflation of inflatable bags;

(3) FIG. 4 is a fragmentary side view of an aircraft in accordance with the invention; and

(4) FIGS. 5 and 6 are two flow charts showing two methods of controlling the inflation of an inflatable bag in accordance with the invention.

(5) Elements present in more than one of the figures may be given the same references in each of them.

DETAILED DESCRIPTION OF THE INVENTION

(6) As mentioned above, and as shown in FIG. 1, the invention relates to a device 1 for controlling the inflation of at least one inflatable safety bag 2. As shown in FIG. 4, such an inflatable bag or airbag 2 may be arranged on a safety harness 22 for the seat 23 of an aircraft 20.

(7) Advantageously, such an aircraft 20 may be an airplane, a rotorcraft, or indeed more particularly, and as shown diagrammatically in FIG. 4, a helicopter.

(8) Firstly, three mutually orthogonal axes X, Y, and Z are shown in FIG. 4 and serves to define the movement of the aircraft in translation along three directions or in rotation about the axes.

(9) Such an orthogonal reference frame thus serves to define the orientation of linear acceleration or of angular acceleration of the aircraft 20, or indeed the dynamic torsor of such an aircraft 20.

(10) As shown in FIG. 1, the control device 1 includes a control member 15 for measuring an acceleration of the aircraft 20, for generating an inflation order, and for transmitting it to an inflation member 10. The inflation member 10 then serves to inflate an inflatable bag 2.

(11) In this first variant of the invention shown in FIG. 1, the control device 1 has a readying system 4 with a first sensor 7 for constantly measuring a first current acceleration A.sub.C1 of the aircraft 10 relative to at least one axis X, Y, Z. By way of example, such a first sensor 7 may be formed by a mechanical sensor for measuring the movement of a flyweight as a function of the first current acceleration A.sub.C1 of the aircraft 20.

(12) The readying system 4 also has a controllable switch 6 that acts as a function of the value of the first current acceleration A.sub.C1 to connect the control member 5 to a source 3 of electricity, or to disconnect it therefrom.

(13) Such a source 3 of electricity may in particular be independent and dedicated to a seat 23. Nevertheless, in other variants in accordance with the invention, such a source 3 of electricity may also be centralized and common to a plurality of control devices 1.

(14) Thus, so long as the absolute value of the first current acceleration A.sub.C1 remains below a first acceleration threshold S.sub.1, the controllable switch 6 remains open.

(15) Nevertheless, when the absolute value of the first current acceleration A.sub.C1 becomes greater than a first acceleration threshold S.sub.1, the controllable switch 6 closes so as to allow electricity to reach the control member 15.

(16) Such a readying system 4 thus serves to limit the electricity consumption of the control member 15 as a function of the absolute value of the first current acceleration A.sub.C1 as measured by the first sensor 7.

(17) In another variant, as shown in FIG. 2, the control device 11 may include a readying system 4 having a first sensor 7 that, in this other variant, may for example be formed by a sensor selected from the group comprising micro-electromechanical systems (MEMS) and nano-electromechanical systems (NEMS) suitable for measuring acceleration relative to at least one axis X, Y, Z.

(18) Furthermore, in a particular embodiment and as shown in FIGS. 1 and 2, the readying system 4, 4 may also include damper means 8 for damping a measurement of the first current acceleration A.sub.C1. These damper means 8 then serve to filter a measurement V.sub.1 of the first current acceleration A.sub.C.sub.1. It is then possible to compare the absolute value of this measurement V.sub.1 with the first acceleration threshold S.sub.1. When the measurement V.sub.1 is greater, in absolute value, than the first acceleration threshold S.sub.1, then the controllable switch 6 is closed in order to elastically connect the source 3 of electricity to the control member 5.

(19) As shown in FIGS. 1 and 2, the control member 15 includes in particular a second sensor 13 suitable for measuring, at least temporarily, a second current acceleration A.sub.C2 of the aircraft 20 relative to at least one axis X, Y, Z. Such a second sensor 13 is advantageously of the miniaturized type such as a MEMS and serves to take a very accurate and fast measurement of the second current acceleration A.sub.C2 of the aircraft 20.

(20) Under such circumstances, it is then possible to envisage subsequently opening the controllable switch 6 in order to disconnect the source 3 of electricity from the control member 15 when the absolute value of the second current acceleration A.sub.C2 becomes less than a third acceleration threshold S.sub.3 and remains less than the third acceleration threshold S.sub.3 for a predetermined number I.sub.1 of comparison iterations i performed by a computer 14.

(21) Specifically, such a control device 1, 11 may also include a computer 14 for iteratively comparing the absolute value of the second current acceleration A.sub.C2 of the aircraft 20 or its mean value A.sub.C2M over a predetermined time interval with various acceleration thresholds.

(22) Thus, the computer 14 serves to compare the absolute value of the second current acceleration A.sub.C2 with the third acceleration threshold S.sub.3 or indeed with a fourth acceleration threshold S.sub.4. Furthermore, the control device 1, 11 may generate an inflation order and transmit this order to the inflation member 10 when simultaneously the absolute value of the second current acceleration A.sub.C2 is greater than the fourth acceleration threshold S.sub.4 and the mean value A.sub.C2M of the second current acceleration A.sub.C2 over a predetermined time interval is greater than a fifth acceleration threshold S.sub.5.

(23) Furthermore, the second sensor 13 may be of the saturated type so as to deliver a measurement of the second current acceleration A.sub.C2 only below a sixth acceleration threshold S.sub.6 that is selected to be higher than the fourth acceleration threshold S.sub.4.

(24) Furthermore, and as shown, the control device 1, 11 may also include a memory 16 for storing data representative of the third, fourth, and fifth acceleration thresholds S.sub.3, S.sub.4, and S.sub.5.

(25) As shown in FIG. 3, in a third variant, the control device 21 may also include a maintenance switch 9 enabling the source 3 of electricity to be disconnected manually from the readying system 4 and/or the control member 15 while performing maintenance operations on the aircraft 20.

(26) Furthermore, it is also possible to envisage increasing the safety of such a control device 21 by providing redundancy for the maintenance switch 9 and/or the readying system 4 and/or the control member 15.

(27) As shown in FIG. 4, and as mentioned above, the invention also provides an aircraft 20, such as a helicopter for example. Such an aircraft 20 is then remarkable in that it includes a device 21 for controlling the inflation of an inflatable bag 2, e.g. fitted to a safety harness 22 of a seat 23.

(28) Such a control device 21 may include in particular a maintenance switch 9 that is actuated magnetically while the seat 23 is being put into place on a guide rail 24 by magnetic means 25 that are secured to the guide rail 24.

(29) Thus, when the seat 23 is removed from its guide rail 24 for a maintenance operation, the maintenance switch 9 is moved away from the magnetic means 25 and opens the electric circuit enabling the readying system 4 and/or the control member 15 to be powered electrically.

(30) Finally, and as shown in FIGS. 5 and 6, the invention also provides a method 50, 51 for controlling the inflation of an inflatable safety bag 2.

(31) Thus, and as shown, the method 50, 51 includes a preliminary measurement step 30 of measuring a first current acceleration A.sub.C1 of the aircraft 20 relative to at least one axis X, Y, Z. A first comparison step 40 then makes it possible to identify whether the first current acceleration A.sub.C1 of the aircraft 20 is less than or greater than a first acceleration threshold S.sub.1.

(32) As shown in FIG. 5, when the absolute value of the first current acceleration A.sub.C1 is greater than a first acceleration threshold S.sub.1, the method 50 activates a step 31 of activating a control member 15 by electrically connecting a source 3 of electricity to the control member 15. Such a connection can thus be performed by means of a controllable switch 6 that is closed in order to enable the control member 15 to be powered electrically.

(33) When the absolute value of the first current acceleration A.sub.C1 is less than the first acceleration threshold S.sub.1, the preliminary measurement step 30 measures the first current acceleration A.sub.C1 of the aircraft 20 relative to at least one axis X, Y, Z.

(34) Thereafter, the method performs a step 33 of measuring a second current acceleration A.sub.C2 of the aircraft 20 by means of a second sensor 13. Such a second sensor 13 may also be saturated, i.e. it may serve to provide a measurement limited to a sixth acceleration threshold S.sub.6 so as to avoid taking account of instantaneous accelerations of very great absolute value. The measurement step 33 then serves to provide a measurement of the second current acceleration A.sub.C2 of the aircraft 20 that is less than or equal to the sixth acceleration threshold S.sub.6.

(35) In a step 42, the absolute value of this second current acceleration A.sub.C2 is then compared with a third acceleration threshold S.sub.3.

(36) Thus, if the second current acceleration A.sub.C2 remains less than the third acceleration threshold S.sub.3 for a predetermined number I.sub.1 of comparison iterations i, a deactivation step 32 for deactivating the control member 15 disconnects the source 3 of electricity from the control member 15. Such a disconnection can thus be performed by means of a controllable switch 6 that is opened to prevent the control member 15 being powered electrically.

(37) Once the deactivation step 32 has been performed, the preliminary measurement step 30 then measures the first current acceleration A.sub.C1 of the aircraft 20 relative to at least one axis X, Y, Z.

(38) Nevertheless, if the absolute of the second current acceleration A.sub.C2 is greater than the third acceleration threshold S.sub.3, a comparison step 43 compares both the absolute value of the second current acceleration A.sub.C2 to a fourth acceleration threshold S.sub.4 and the mean value A.sub.C2M of the second current acceleration A.sub.C2 over a predetermined time interval with a fifth acceleration threshold S.sub.5.

(39) If the absolute value of the second current acceleration A.sub.C2 is greater than the fourth acceleration threshold S.sub.4 and the mean value A.sub.C2M of the second current acceleration A.sub.C2 over a predetermined time interval is greater than the fifth acceleration threshold S.sub.5, the method 50 activates the following step 34, which consists in generating an inflation order and transmitting this inflation order to the member 10 for inflating the inflatable bag 2 since it has been identified that an accident of the aircraft 20 is imminent.

(40) As shown in FIG. 6, the method 51 of controlling inflation of an inflatable bag 2 may also include a storage step 35 consisting in storing in a memory 16 data that is representative of the third, fourth, and fifth acceleration thresholds S.sub.3, S.sub.4, and S.sub.5. Such a memory 16 then advantageously forms part of the control member 15.

(41) In this second example, the method 51 includes a filtering step 36 of filtering a measurement V.sub.1 of the first current acceleration A.sub.C1 of the aircraft 20. Furthermore, this filtering step 36 is performed by the damper means 8 so as to avoid taking account of variations in the first current acceleration A.sub.C1 that are too slow.

(42) Thereafter, a comparison step 41 compares the absolute value of this measurement V.sub.1 of the first current acceleration A.sub.C1 with the first acceleration threshold S.sub.1.

(43) When the measurement V.sub.1 is less than the first acceleration threshold S.sub.1, the preliminary measurement step 30 measures the first current acceleration A.sub.C1 of the aircraft 20 relative to at least one axis X, Y, Z.

(44) In contrast, if the measurement V.sub.1 of the first current acceleration A.sub.C1 is of absolute value greater than the first acceleration threshold S.sub.1, that indicates there is a risk of an accident for the aircraft 20. The method 51 then activates a step 31 of activating a control member 15 by connecting a source of electricity to the control member 15.

(45) Furthermore, in this variant of the method 51, once the step 31 of activating the control member 15 has taken place, there is a step 44 of comparing the absolute value of the first current acceleration A.sub.C1 of the aircraft 20 with a second acceleration threshold S.sub.2.

(46) If the first current acceleration A.sub.C1 of the aircraft 20 is less than the second acceleration threshold S.sub.2 for a predetermined duration T.sub.1, then the method 51 performs a step 32 of deactivating the control member 15. As before, once the deactivation step 32 has been performed, the preliminary measurement step 30 then measures the first current acceleration A.sub.C1 of the aircraft 20 relative to at least one axis X, Y, Z.

(47) In contrast, if the absolute value of the first current acceleration A.sub.C1 of the aircraft 20 is greater than the second acceleration threshold S.sub.2, a measurement step 33 then measures a second current acceleration A.sub.C2 of the aircraft 20 by means of a second sensor 14.

(48) As in the method 50, the method 51 then includes a step 42 of comparing the absolute value of this second current acceleration A.sub.C2 with a third acceleration threshold S.sub.3.

(49) The method 51 then continues in a manner identical to the method 50 as described above with reference to FIG. 5.

(50) Naturally, the present invention may be subjected to numerous variations as to its implementation. Although several embodiments are described, it will readily be understood that it is not conceivable to identify exhaustively all possible embodiments. It is naturally possible to envisage replacing any of the means described by equivalent means without going beyond the ambit of the present invention.