Method for validating a detection of crossing of the karman line by an object portable by a user, in particular a watch

Abstract

A method for verifying the detection of Kármán line intersections by objects portable by a user, particularly watches. The verification method relates to the detection of a Kármán line crossing by a portable object (2) that is mounted on a rocket and transported, and incorporates a detection device comprising an acceleration sensor (8) capable of measuring the accelerations of the portable object and an electronic unit for processing the acceleration measurements taken to detect the Kármán line crossing by the portable object. The verification method calculates at least one reliability index in relation to measurements taken by the portable object for at least one variable which is a function of forces applied to the portable object, and checks whether at least one condition given for the at least one reliability index is satisfied, thereby verifying or not verifying the detection of a Kármán line crossing by the portable object and the rocket accordingly. The present invention further relates to a method for detecting a Kármán line crossing and a portable object, in particular a watch, designed to enable the implementation of the verification method of the present invention.

Description

Technology Field

[0001] The present invention relates to a space application, to an object portable by a user, in particular a watch, the user being an astronaut or another individual traveling in space by rocket or space shuttle (hereinafter both referred to as 'rocket'). More specifically, the present invention relates to an autonomous detection device, wherein the Kármán (by means of such portable object provided for this purpose) This relates to a method for verifying the detection of crossing of lines, and the verification method is implemented by a portable object.

[0002] The Kármán line defines the conventional boundary between Earth's atmosphere and space. Typically, this is agreed to correspond to an altitude of 100 km; however, this altitude varies depending on the organization, particularly between 85 km and 110 km. The Kármán line is also the boundary at which a spacecraft must fly at a substantial orbital speed to maintain its orbit around the Earth in order to sustain flight. Background Technology

[0003] Astronauts wore a variety of watches for space missions. Some of the watches worn by astronauts were selected for their robustness and precision, without possessing any functions specific to flight or missions in space. Other watches, particularly electronic ones, provide specific functions useful for missions in space. These specific functions typically relate to time measurement, for example, for countdowns and / or alarms.

[0004] The object of the present invention is to provide a method for verifying the detection of a Kármán line intersection by an object portable by a user, in particular a watch, wherein both detection and verification are performed by the portable object based on measurements taken by the portable object during the detection phase of the detection method implemented by the portable object. Accordingly, such detection is intended to be performed autonomously by the portable object during the detection phase of the detection method implemented by the portable object, and thus not by any real-time communication between the portable object and a rocket, or by an external system, in particular one or more satellites supplying position information in space. The present invention also relates to such an object portable by a user.

[0005] In particular, the portable object is intended to include a detection device formed by an acceleration sensor, a time base, and an electronic unit, wherein the detection device measures accelerations experienced by the portable object during the detection phase of the detection process / method implemented by the portable object, and processes the acceleration measurements taken in the electronic device, and is arranged to enable the detection of a crossing of the Kármán line by the portable object based on these acceleration measurements, and in an advantageous alternative embodiment, based on a reference value calculated as a function of a predetermined correction factor or at least one predetermined reference value, and based on an altitude selected by the user for the Kármán line within a given range of values, particularly between 85 and 110 km. It should be understood that the data considered by "predetermined" is recorded in the portable object prior to the detection phase of the detection process / method.

[0006] It is not possible for a portable object, such as a watch, to integrate a high-performance inertial navigation system having an accelerometer designed to accurately measure acceleration along three axes of the coordinate frame of the portable object and an angular velocity sensor (gyrometer) designed to accurately measure angular velocity along these three axes, which would allow the position of the portable object to be accurately determined in a fixed ground coordinate frame. Furthermore, the cost of a precise inertial navigation system is very high. Therefore, in a preferred embodiment, the portable object according to the present invention is notable in that, as the only necessary technical means, it is designed to autonomously detect the crossing of a Kármán line by the portable object mounted on a given type of rocket, comprising an accelerometer capable of measuring components of an acceleration vector for the portable object in a coordinate frame linked to the portable object, a memory containing the predetermined reference value or the calculated reference value, and an electronic unit arranged to process the measurements supplied by the accelerometer. Therefore, in order to detect whether a portable object has crossed a Kármán line, this portable object does not require a gyroscope, which is formed by a microelectromechanical system (also known as 'MEMS'), which is certainly small but typically relatively inaccurate and in any case not accurate enough to allow precise detection of changes in the orientation of the coordinate frame specific to the acceleration sensor during space flight, thereby determining the vertical component of the rocket's motion acceleration at any time between takeoff and crossing the Kármán line, and thus allowing its altitude to be determined over time.Therefore, regarding the measurements required to detect the intersection of Kármán lines, this preferred embodiment avoids the problems associated with small gyroscopes, which are relatively inaccurate and thus cannot provide sufficiently accurate measurements of the angular velocity of a portable object to accurately determine its instantaneous orientation and subsequent changes in its position in space, particularly its altitude, whereas a relatively inexpensive 3D accelerometer of the same size and dimension can provide accurate acceleration measurements along three axes.

[0007] In a preferred alternative embodiment, a method for detecting the intersection of Kármán lines provides for calculating a comparison distance based on norms of acceleration vectors measured by an acceleration sensor, and an electronic unit is arranged to calculate these norms and perform a double integral over time of these norms or norms of periodically measured acceleration vectors that are less than gravitational acceleration—advantageous to the case of a MEMS type accelerometer—in order to obtain a virtual comparison distance that is compared with the above-mentioned calculated reference value or a predetermined reference value. The acceleration sensor provides acceleration vectors in an appropriate coordinate frame, but the norms of the acceleration vectors are independent of the coordinate frame, that is, they are not variable regardless of the cosmic orientation of the coordinate frame in which these acceleration vectors are given, so that the uncertainty of the orientation of the measurement coordinate frame for the acceleration measurements is no longer a problem. This desirable alternative embodiment is highly advantageous because it overcomes the fact that the coordinate frame linked to the portable object—that is, the coordinate frame defined by the accelerometer fixed to the portable object—has an orientation relative to the ground coordinate frame, which is variable during space flight between the rocket launch base and the Kármán line, particularly since the rocket does not follow a vertical linear trajectory. Furthermore, the orientation of the portable object can change over time relative to the rocket as a result of the movements of the wearer, especially in the case of a wristwatch.

[0008] For this purpose, during the development of a method for detecting a portable object and the crossing of Kármán lines by the portable object, using periodic measurements of the acceleration vector of the portable object as the sole measurements accompanying the detection phase of the detection method and based on calculations regarding the standards of the measured acceleration vectors, the inventors realized that in certain specific situations, this method can lead to an erroneous result, namely the detection of the crossing of Kármán lines by the portable object when the event has not occurred. This is referred to as a 'false positive'. This is problematic for portable objects, particularly watches intended to indicate an exceptional event to their user, namely a trip to space. Therefore, it is desirable to find a solution to determine the possibility of the portable object autonomously detecting the crossing of Kármán lines during the detection phase, so that such detection can be verified or cannot be verified.

[0009] Among the situations that may lead to false results from the conceived detection method, particularly from a preferred alternative embodiment, there is a situation in which a portable object is subjected to continuous rapid acceleration, for example, a series of impacts occurring close to each other. This can occur in a number of voluntary or involuntary situations, or even when playing sports such as tennis or table tennis while wearing a watch designed for the space application on the wrist. Other activities, such as running, can additionally lead to false detections even without the watch worn on the user's wrist receiving strong impacts. Furthermore, aerobatic flying in an airplane can easily result in "false positives," as in the case of a "roller coaster," when the wearer boards a piece of equipment subjected to relatively high acceleration, as well as certain attractions at an amusement park. Other specific situations can also lead to the detection of a false Kármán line intersection in this context, for example, when the watch is placed in a device that applies a significant centripetal force to an object placed inside the device (e.g., a clothes dryer or even a salad spinner). Accordingly, the object of the present invention is to provide means for detecting at least a predetermined number of cases where the detection of Karman line intersections is uncertain, impossible, or impossible, so as to nullify such erroneous detections.

[0010] To solve the problem mentioned above, the present invention relates to a method for verifying the detection of a Kármán line crossing defined by a predetermined altitude by an object portable by a user, comprising an acceleration sensor, a time base, and an electronic unit, wherein the detection device measures accelerations experienced by the portable object during the detection phase of the method for detecting a Kármán line crossing implemented by the portable object, and the electronic unit processes these acceleration measurements to enable the detection of a Kármán line crossing by the portable object based on data recorded on the portable object prior to the detection phase of the detection method and these acceleration measurements. The method for verifying the detection of a Kármán line crossing utilizes continuous measurements made by the portable object for at least one variable dependent on at least one force applied to the portable object during the detection phase of the detection method. The verification method is performed by an electronic unit that calculates at least one reliability index related to the above continuous measurements and then checks whether at least one condition given for the at least one reliability index is satisfied, thereby verifying or not verifying the detection of the crossing of the Karman line by the portable object.

[0011] In a favorable alternative embodiment, the acceleration sensor measures the appropriate acceleration vector of the portable object in the coordinate frame of this clock. The variable is the standard for the appropriate acceleration vector less than the standard for gravitational acceleration, and the appropriate acceleration vector of the portable object is equal to the vector sum of the forces acting on the portable object, excluding gravity, divided by its mass.

[0012] In a preferred alternative embodiment, the portable object further comprises an angular velocity sensor (gyrometer), and the reliability index is defined by a function given for angular velocity measurements, preferably performed periodically, by the angular velocity sensor. Advantageously, the angular velocity sensor (gyrometer) is formed by a microelectromechanical system (MEMS). Brief explanation of the drawing

[0013] The present invention will be described in more detail below with reference to the accompanying drawings, which are given as examples that are not limited in any way: - FIG. 1 schematically illustrates a clock according to a preferred embodiment of the present invention; - Fig. 2 shows the Kármán line L during flight in space. K Between the intersection and takeoff, the trajectory T taken by the rocket, which is interrupted in the drawing F　 (x) as well as various variables related to flight along this trajectory, which are associated with an advantageous method for detecting the intersection of Kármán lines; - FIG. 3 shows an enlarged view of FIG. 2 of the vector sum of various accelerations accompanying an advantageous detection method that provides for measuring the appropriate acceleration of a clock, and the orthogonal axes X t and Z t is the rocket trajectory T parallel to and related to the X and Z axes of Fig. 2. F　 (x) Top point P S　 With their origin at (t), this point P S　 (t) is altitude H F　 Defines (t); - Fig. 4 shows the theoretical curve of the motion acceleration of a certain type of rocket as a function of time; - Fig. 5 shows the theoretical curve for the angle of inclination of the rocket over time; and - Figure 6 shows a theoretical curve for the altitude of the rocket over time, defining the theoretical flight time between the crossing of the Kármán line and the rocket takeoff. Specific details for implementing the invention

[0014] With reference to the drawings, an advantageous embodiment of a clock according to the present invention, an advantageous method for detecting the intersection of Karman lines by the clock according to the present invention, and a method for verifying the detection of the intersection of Karman lines according to the present invention will be described below.

[0015] The watch (2) includes a memory (4), a time base, and a detection and verification device (6), the device includes an acceleration sensor (8) capable of measuring the acceleration vector of the watch in a three-dimensional coordinate frame linked to the watch, and an electronic processing unit (12), also referred to as the ‘electronic unit’ below, which is arranged to process measurements supplied by the acceleration sensor (8). The watch further includes an electronic control unit (14), which is arranged to activate the detection and verification device (6) in response to the operation of an external control member. The watch (2) is equipped with various external control members, in particular a stem-crown (18) and two push-buttons (16, 17) arranged on the case (20) to the outside. The watch may be equipped with a tactile crystal covering a tactile control means, particularly a display means, and such tactile control means is provided to control the display of a certain data, for example, by the display means, for data entered into the watch memory (4) and / or by the display means, particularly before and after space flight or space mission. In a specific alternative embodiment, the watch includes an analog display formed by hands associated with a scale, and a digital display formed by an electronic display module defining a major part of the watch dial.

[0016] The electronic unit (12), in relation to the acceleration sensor (8) and memory (4), for at least a given type of rocket, only by the watch (2) mounted on this rocket, the Kármán line L by the rocket K It is arranged to detect the intersection of. Accordingly, detection is performed autonomously by a detection device included in the detection and verification device (6) of the clock during the detection phase of the detection method implemented by the clock. Karman line L K is the given altitude H D Altitude H, which can be selected directly or through the selection of other cosmic variables, within a range of values ​​given by or by the user, specifically between 85 and 110 km. S It is defined by. 'Given altitude' means an altitude predefined / predetermined by the watch manufacturer or an authorized person or company, not by the user.

[0017] Altitude H selected by a given type of rocket (22) by a clock (2) mounted on this rocket S by, or given altitude H D The Kármán line L defined by K An advantageous detection method for detecting the intersection of is, in a 3D coordinate frame in which an acceleration sensor (8) is linked to this clock, the acceleration vector a of the clock M It is arranged to measure *, and the electronic unit (12) is provided to be arranged to process the measurements supplied by the acceleration sensor. Appropriate acceleration vector a M * is the first approximation for the rocket, where the gravitational acceleration vector a at the acceleration of this clock's motion vector a* at any moment / arbitrary time t is EIt is equivalent to subtracting *. It should be noted that here, the asterisk (*) is used to denote a vector, whereas in FIGS. 2 and 3, vectors are indicated in the conventional manner by arrows placed over the relevant variables. The appropriate acceleration vector of the clock is equal to the vector sum of the forces experienced by the clock, excluding gravity, divided by its mass. That is, the appropriate acceleration of the object is the acceleration that this object experiences relative to an observer in free fall.

[0018] The detection method includes a preliminary phase preceding the placement of a portable object mounted on a rocket for a scheduled space flight, comprising the following preliminary steps:

[0019] A) At least the Kármán line L K given altitude H for D Motion A for the rocket (22) as a function of time t from rocket takeoff, defining time 0, until one pass through N　 Step providing the nominal acceleration of (t), this nominal acceleration of the motion is a scalar value of the same unit as Earth's gravity (the standard of the motion's nominal acceleration) (accordingly, this dimensionless scalar value corresponds to the standard of the vector of the motion's nominal acceleration divided by the standard of Earth's gravity).

[0020] B) Altitude H given from rocket takeoff D The theoretical angle of inclination θ for a given type of rocket as a function of time t and with respect to the horizontal plane, up to at least one intersection. T　 Step providing (t).

[0021] C) Altitude H given from rocket takeoff D Theoretical flight time T for a given type of rocket up to the crossover K The step of providing or determining.

[0022] D) Based on the above nominal acceleration of the motion and the above theoretical angle of inclination, for a given type of rocket, the theoretical optimal acceleration A as a function of time PT Step to determine (t), this theoretically appropriate acceleration value is defined by the following formula in the same units as Earth's gravity:

[0023]

[0024] E) Time T corresponding to this theoretical appropriate acceleration, or the theoretical flight time, which is less than the standard of gravitational acceleration by numerical and / or mathematical means. K Between the time 0 (t = 0) corresponding to rocket takeoff, the theoretical optimal acceleration A PT　 Theoretical measured distance D defined by the double integral of (t) MT Step to calculate; Kármán line L K given altitude H for D Theoretical measured distance D divided by MT is, for a given type of rocket, a correction factor F C Defines.

[0025] F) Theoretical measurement distance D MT and / or correction factor F C The step of recording to the watch memory, this correction factor F C is thereafter, where applicable, prior to the liftoff of the rocket defining the start of the space flight, reference distance D MR Altitude H selected to acquire S It is likely to be won.

[0026] Thereafter, the detection method includes a detection phase comprising the following detection steps:

[0027] G) A step of activating the detection device of the clock mounted on the rocket before the rocket takeoff.

[0028] H) Measurement frequency F MIn this, the appropriate acceleration vector of the clock is periodically measured by the detection device in the 3D coordinate frame of the clock, and in the electronic unit, for each measurement, the standard A of the measured appropriate acceleration vector M　 (t n The step of calculating ), where each corrected standard is standard A less than the standard of the acceleration vector M　 (t n Same as ) and t n is the same time as n·P, where n is the number of measurements taken since at least rocket takeoff, incremented by one unit with each new measurement, and P is the time period defined by the measurement frequency.

[0029] I) In an electronic unit, a step of numerically calculating the double integral over time of the standard of the appropriate acceleration vector of the clock, which is less than the standard of the gravitational acceleration, respectively, from rocket takeoff, at least from rocket takeoff, wherein the standard of the appropriate acceleration vector is at times t m Comparison distances D regarding C　 (t m In order to obtain ) (where m is a positive integer and each m corresponds to one of the aforementioned numbers n), the aforementioned standards A of the appropriate acceleration vectors measured periodically M　 (t n It is determined based on ).

[0030] J) Given altitude H D In the case of theoretical measurement distance D MT and, or selected altitude H S In the case of reference distance D MR and respective comparison distance D C (t m Compare ) and comparison distance D C (t m ) is the theoretical measured distance D MT , or respectively, reference distance D MRWhen larger than, a step of recording the detection of the Karman line intersection by the portable object in the memory of the portable object by the detection device.

[0031] The term ‘acceleration of motion’ is understood to mean acceleration corresponding to the time derivative of velocity, and this acceleration of motion defines a vector that is always tangent to the trajectory of the rocket and, accordingly, the portable object in space, that is, a vector collinear with the instantaneous direction vector of the rocket. The term ‘nominal’ is understood to mean a value given in the specifications for the rocket type or for a given rocket; thus, this is a theoretical value, in this case time-dependent, predicted for the rocket and derived from its design and from the plan of space flight with such rocket, particularly in the context of the present invention, until it crosses the Kármán line.

[0032] In a preferred alternative embodiment of the detection method, the acceleration sensor used to measure the appropriate acceleration vector of the clock, and thereby the appropriate acceleration vector of the rocket in general, is a microelectromechanical system (MEMS) integrated into the clock.

[0033] In relation to Step A), Motion A N The theoretical acceleration of (t) can be instantaneously negative, that is, the speed of the rocket can instantaneously decrease as shown in the graph of Figure 4. Therefore, the nominal acceleration of the motion is provided by its mathematical sign, and this mathematical sign must be entered into the formula given in step D).

[0034] With respect to step B) of the detection method, FIG. 5 shows the theoretical inclination angle θ of the rocket involved as a function of time. T I will show an example for the curve of (t). Time T B Up to, the rocket has a theoretical angle of inclination θ T (t) is at time 0 and time T BFollow the vertical direction so that it forms a 90° angle between them.

[0035] Figure 2 shows the trajectory z = T of the rocket (22). F (x) is illustrated as an example (the trajectory is interrupted in this figure for reasons of scale). It should be noted that the examples given in the figures do not limit the theoretical curves that can be conceived in any way, and that these are typically specific to each type of rocket (particularly the type of launch vehicle for the Space Shuttle). At time t, the angle of inclination θ(t) between the rocket's direction at time t and the horizontal plane is, its space position P S　 Rocket trajectory z = T at (t) F　 It is defined by the tangent line to (x), and the variable x is a function of time.

[0036] Theoretical flight time (T K With respect to step C) concerning ), in a simplified alternative embodiment, it is possible to estimate this theoretical flight time based on at least one previous space flight with a rocket of the relevant type. In a favorable alternative embodiment, the theoretical flight time T K is the theoretical angle of inclination θ of the rocket T　 (t) and motion A N　 It will be determined by mathematical and numerical means based on the nominal acceleration of (t). To this end, the theoretical distance L traveled by the rocket as a function of time. T By defining (t), the following approach can be taken. The theoretical altitude H of a rocket in flight. FT (t) and the theoretical distance L traveled by this rocket T A mathematical relationship can be established between (t). Theoretical altitude dH FT　 (t) = dL T　 (t) 　 ·sin θ T　 (t) (here, dH FT　The minimum / fundamental variation at (t) is the minimum / fundamental variation at the shifted theoretical distance. On the other hand, the variation dL T　 (t) = V N　 (t) ·dt and here V N (t) is the nominal velocity of the rocket at time t, and dt is the minimum / fundamental variation at time. Nominal velocity V N Given that (t) is equal to the integral of the acceleration over time, motion A N It can be determined mathematically and / or numerically based on the nominal acceleration of (t). Therefore, as a function of given (nominal / theoretical) variables, based on the mathematical relationships given above, the theoretical altitude H FT Minimum / basic variation dH of (t) FT (t) can be defined. This provides the following:

[0037] , here

[0038] Theoretical altitude H FT (t) is dH calculated by mathematical and / or numerical means FT It is equivalent to the integral over time (t). Theoretical flight time T K To determine, equation H FT 　 (T) = H D is resolved, and here H D is the given altitude and T is a variable.

[0039] Fig. 6 is motion A given in Fig. 4. N (t) Nominal acceleration of the curve and the theoretical angle of inclination θ given in Fig. 5 T　 Theoretical altitude H as a function of time based on the (t) curve FT　 This shows an example of the curve of (t).

[0040] Steps D) and E) of the detection method are a theoretical measurement distance D corresponding to a predetermined reference value, to which a comparison distance subsequently and accurately calculated in the electronic unit of the watch based on appropriate acceleration measurements supplied by an acceleration sensor (8) arranged in the watch during space flight in a rocket carrying the watch can be compared. MT It is characterized by being designed so that it can be accurately determined. In a primary embodiment of the watch (2), the autonomous detection device is considered to use only acceleration sensors arranged to measure vectors of appropriate acceleration experienced by the watch as its measuring means to detect the crossing of the Kármán lines. This method is used in advance, that is, in a preliminary stage prior to the space flight, for the theoretical measurement distance D MT It involves determining a virtual theoretical distance in that it does not correspond to the distance theoretically traveled by the rocket between the ground and the Kármán line, but rather corresponds to the theoretical distance derived from the fact that the appropriate acceleration of the clock is being measured. Additionally, given a limited means of measurement, a reference value will be supplied, and this value depends only on the standard of appropriate acceleration and the trajectory of the rocket, the vector of which is supplied by the acceleration sensor in the coordinate frame of the clock (2) and, advantageously, corrected by the standard of gravitational acceleration by subtracting it from the standard of appropriate acceleration. Thus, the intersection of the Kármán line is intended to be defined based on the standard of appropriate acceleration of the clock and, accordingly, the standard of the rocket that generally carries it.

[0041] The detection method considers that the standard for the appropriate acceleration vector for a given motion acceleration varies with the inclination of the rocket. In effect, this standard, which is less than the standard for gravitational acceleration, does not provide the acceleration of the clock / rocket motion when the rocket does not have a vertical direction. Figures 2 and 3 show, for the rocket, the motion acceleration a* and the measured appropriate acceleration a M* and gravitational acceleration a E * Represents the vector relationship between. The acceleration of the motion vector a(t)* and the measured appropriate acceleration vector a M (t)* is the rocket's space position P at the time of spaceflight t. S Corresponding to (t), and the gravitational acceleration vector a E It should be noted that the small centripetal acceleration experienced when the rocket is gradually tilted is not taken into account in the relationship between the rocket's optimal acceleration and the rocket's motion acceleration, as this centripetal acceleration is small and negligible for the rocket between the ground and the Kármán line.

[0042] Step F) is the theoretical measured distance D in the clock's memory before space flight, that is, before rocket takeoff. MT and / or correction factor F C Provides saving of correction factor F C is the altitude H selected by the user for the Kármán line S Reference distance D when expected to be provided to the watch MR It is useful for obtaining, and correction factor F C In this case, the altitude H selected for the Kármán line S Multiplied by reference distance D MR Calculate the given altitude H D Theoretical measurement distance D, precisely determined for MT Given the linear approximation performed here from, this reference distance D MR It should be noted that this is, in fact, an approximate theoretical distance.

[0043] For the reasons set forth in the summary of the present invention, the detection of Kármán line crossings by clock, which is advantageously arranged to implement the detection method described above, is reliable as long as the detection device is activated during space flight, preferably just before liftoff, but nevertheless, this detection method has the major disadvantages already mentioned. In fact, the advantageous detection method described previously is characterized by using, advantageously, a MEMS-type 3D accelerometer as the sole sensor to detect Kármán line crossings; however, such detection can be incorrectly obtained in certain situations.

[0044] Generally speaking, a method for verifying the detection of a Kármán line crossing defined by a predetermined altitude is implemented by an object portable by a user, and during the detection phase of the method for detecting a Kármán line crossing implemented by the portable object, the accelerations of the portable object are measured and processed in an electronic unit so as to enable the detection of a Kármán line crossing by the portable object based on these acceleration measurements and data recorded in the portable object prior to the detection phase of the detection method. According to one general implementation, the method for verifying the detection of a Kármán line crossing utilizes continuous measurements taken by the portable object for at least one variable dependent on at least one force applied to the portable object during the detection phase of the detection method. The verification method is performed by an electronic unit that calculates at least one reliability index related to the continuous measurements and checks whether at least one given condition is satisfied for the at least one reliability index to verify or not verify the detection of a Kármán line crossing by the portable object.

[0045] Three specific reliability indices are described below, which make it possible to verify the detection of the crossing of the Karman line by the clock using conditions given to each of at least one of these reliability indices, which are checked during the verification process.

[0046] The first reliability index C1(N) is defined by the following function:

[0047]

[0048] N is the number of acceleration measurements performed during the detection phase of the considered detection method, and A j is the value of acceleration supplied by the acceleration sensor during the j-th acceleration measurement or calculated by the electronic unit based on this j-th acceleration measurement, where j = 1 to N. The value L1 is acceleration values ​​A j This is a given restriction on.

[0049] The δ function provides a value of '1' if the relevant condition is true / satisfied, and a value of '0' if the condition is false / unsatisfied. Therefore, C1(N) has a value between '0' and '1'. The closer the value of the function C1(N) is to '1', the greater the confidence in the detection of Karman line intersections.

[0050] The second reliability index C2(N) is defined by the following function:

[0051]

[0052] N is the number of acceleration measurements taken during the detection phase of the considered detection method, and V q The above values ​​A for j = 1 to q j It is the speed obtained by the numerical integration of the acceleration determined by over time. The value L2 is a limit given for the above speed. C2(N) also has a value between '0' and '1'. The closer the value of the function C2(N) is to '1', the greater the confidence.

[0053] In particular, the velocity V after q consecutive measurements are taken at a frequency F equal to 1 / P. q Incremental integration can be used to determine speed V q is actually the increase in speed over the time interval q·P during which these q consecutive measurements are taken. Therefore, speed V q is given by the following equation.

[0054]

[0055] The third reliability index C3(M) is defined by the following function:

[0056]

[0057] M is the number of angular velocity measurements taken by the angular velocity sensor (gyrometer) integrated into the watch for this purpose during the detection phase of the considered detection method. W k is the value of the angular velocity supplied by the angular velocity sensor during the k-th angular velocity measurement and calculated based on the k-th measurement, where K = 1 to M. The value L3 is the value W k This is a given constraint. The function C3(M) has a value between '0' and '1'. The closer the value of C3(M) is to '1', the greater the confidence in the detection of Karman line intersections.

[0058] It should be noted that, according to three basic alternative embodiments, the verification method according to the present invention relates to a single reliability index among three reliability indices, and to individual given conditions that are at least verified after the detection of the crossing of the Karman line by the clock. In the basic alternative embodiment related to the third reliability index, the angular velocity sensor (10) is also integrated into the clock (2) and associated with the detection device to form a detection and verification device capable of implementing the verification process. The given condition checks whether the third reliability index C3(M) is greater than a reference value R2 selected between '0.5' and '1'. In a preferred alternative embodiment, the reference value R2 is selected from '0.7' to '0.9'. In a specific case, the value L3 is equal to 200 rad / s and the reference value R2 is equal to 0.8.

[0059] In a favorable alternative embodiment, because this is safer, the verification method relates to first and second reliability indices and the same given condition for these first and second reliability indices. In a specific case, the same given condition is a condition for the average of the first reliability index and the second reliability index. This same condition checks whether the average is greater than a first reference value (R1), which is selected between '0.5' and '1'. In a preferred alternative embodiment, the first reference value R1 is selected from '0.7' to '0.9'. In a specific case for a given type of rocket, the value L1 is 20 m / s 2 It is the same as, the value L2 is the same as 1000 m / s, and the reference value R1 is the same as 0.8.

[0060] In a specific alternative embodiment regarding the advantageous detection method described above, the acceleration sensor (8) measures the appropriate acceleration vector of the portable object in the coordinate frame of this watch, and the acceleration value A jis the standard for the appropriate acceleration vector below the standard for gravitational acceleration, and thereby this appropriate acceleration vector is obtained during the j-th acceleration measurement. It should be noted that the appropriate acceleration vector of the clock is equal to the vector sum of the forces experienced by the clock, excluding gravity, divided by its mass. In this case, the acceleration sensor is a microelectromechanical system (MEMS).

[0061] In a favorable alternative embodiment, the verification method relates to three reliability indices and at least one given condition regarding the three reliability indices. In a preferred alternative embodiment, the verification method relates to three reliability indices and provides a first given condition related to the first and second reliability indices and a second given condition related to the third reliability indices. Thus, verification of the detection of a Karman line crossover is obtained as long as the two given conditions are satisfied. In a specific case, the first condition is identical to the condition for the average of the first and second reliability indices given in advance, and the second condition is also identical to the condition for the basic alternative embodiment regarding the third reliability indices given in advance. This preferred alternative embodiment makes it possible to exclude erroneous results ('false positives') in all specific situations listed in the summary of the invention.

[0062] In a preferred alternative embodiment, the angular velocity sensor is formed by a microelectromechanical system (MEMS). It was noted in the summary of the invention that MEMS-type angular velocity sensors lack accuracy and are not suitable for accurately detecting the crossing of Kármán lines. The invention does not disregard this fact; however, the inventors have found that such angular velocity sensors can nevertheless provide data accurate enough to allow them to be used in a method for verifying the detection of the crossing of Kármán lines according to the invention. Thus, the crossing of Kármán lines is intended to be detected without using measurements from a gyroscope, and this detection is subsequently verified using measurements from a gyroscope, and the accuracy of this gyroscope is relatively insignificant when verifying this detection by eliminating false detections ('false positives') in situations involving relatively high centripetal force.

[0063] The present invention also relates to an object portable by a user, in particular a watch (2), comprising a detection device formed by an acceleration sensor (8), a time base, and an electronic unit (12), wherein the detection device is configured to preferably periodically measure the accelerations of the portable object by the acceleration sensor. The detection device is configured to autonomously detect the crossing of a Kármán line, defined by a predetermined altitude, by the portable object during the space flight of the rocket, by processing at least the acceleration measurements taken during the space flight in the electronic unit. Subsequently, the detection device also forms part of a detection and verification device (6) configured to implement a method for verifying the detection of the crossing of a Kármán line by the portable object according to the present invention.

[0064] In a preferred embodiment, the portable object, in particular the watch (2), further comprises an angular velocity sensor (10) associated with the detection device to implement a verification method according to a preferred alternative embodiment; the electronic unit (12) is arranged in such a manner that the method for verifying the detection of a Karman line crossing is implemented by this portable object, and the verification method uses a reliability index regarding the angular velocity, in particular a third reliability index and a given condition regarding it. Accordingly, within the scope of the present invention, the detection device is also developed to be a device for verifying each detection. More specifically, the device (6) comprises a part for the actual detection of a Karman line crossing and a part for verifying such detection, and these two parts share hardware resources, in particular the electronic unit. Thus, the device (6) is a device for detecting a Karman line crossing and verifying each detection. An angular velocity sensor is not provided and is therefore used in the detection part specifically designed to detect a Karman line crossing; however, the angular velocity sensor (10) is advantageously provided in the part for verifying each detection.

[0065] In a favorable alternative embodiment, the angular velocity sensor (10) is formed by a microelectromechanical system (MEMS).

Claims

Claim 1 A Karman (defined by a predetermined altitude by an object portable by a user, comprising an acceleration sensor, a time base, and a detection device formed by an electronic unit) A method for verifying the detection of a line intersection, wherein the detection device measures accelerations experienced by the portable object during the detection phase of the method for detecting a Kármán line intersection implemented by the portable object, and the electronic unit processes these acceleration measurements to enable the detection of a Kármán line intersection by the portable object based on the acceleration measurements and data recorded on the portable object prior to the detection phase of the detection method; and the method for verifying the detection of a Kármán line intersection utilizes continuous measurements performed by the portable object during the detection phase of the detection method for at least one variable dependent on at least one force applied to the portable object; A method for verifying the above is performed by an electronic unit, which calculates at least one reliability index regarding the continuous measurements and then checks whether at least one condition given for the at least one reliability index is satisfied to verify or not verify the detection of the crossing of the Karman line by the portable object, and the time base is used to continuously determine the period for measuring the acceleration. Claim 2 A method for verifying the detection of a Karman line intersection according to claim 1, characterized in that the reliability index is defined by the following function: In the equation, N is the number of acceleration measurements performed, C1(N) is the reliability index for the N measurements, and A j is the value of acceleration supplied by the acceleration sensor during the j-th acceleration measurement or calculated by the electronic unit based on the j-th acceleration measurement, where j = 1 to N, and the value L1 is the values ​​of acceleration A j This is a given constraint on, and the δ function provides a value '1' if the condition it is associated with is true and a value '0' if this condition is false, and C1(N) therefore has a value between '0' and '1'. Claim 3 A method for verifying the detection of a Kármán line intersection by the portable object, wherein the reliability index is a first reliability index, the function is a first function, and the given condition is a first condition; the electronic unit further calculates a second reliability index, wherein the second reliability index is defined by a second function given for the acceleration measurements, and verifies the given first condition when the given first condition is also related to the second reliability index, or verifies the given second condition when the opposite is true; and wherein the second reliability index is defined by the following function: C2(N) is the second reliability index for the N acceleration measurements performed, the value of which is between '0' and '1', and V q The above values ​​A for j = 1 to q j The speed is obtained by numerical integration of the acceleration over time determined by, and the value L2 is a limit given for the speed. Claim 4 In claim 3, the given first condition relates to the first reliability index and the second reliability index, and the given first condition is, at least, that the processing of the acceleration measurements performed by the electronic unit is N K A method for verifying the detection of a Karman line crossing, characterized in that, after acceleration measurements are taken, the portable object is provided to verify or not verify the result, and the first condition is a condition for the average of the first and second reliability indices, and the condition is satisfied when the average is greater than a first reference value (R1) selected between '0.5' and '1' or from '0.7' to '0.9'. Claim 5 In any one of claims 2 to 4, the acceleration sensor measures an appropriate acceleration vector of the portable object in the coordinate frame of the portable object, and the value A of the acceleration j A method for verifying the detection of a Kármán line intersection, characterized in that the appropriate acceleration vector obtained during the j-th acceleration measurement is less than the norm of gravitational acceleration, and the appropriate acceleration vector of the portable object is equal to the vector sum of the forces received by the portable object, divided by its mass, excluding the force of gravity. Claim 6 A method for verifying the detection of a Karman line intersection according to claim 5, characterized in that the acceleration sensor is formed by a microelectromechanical system (MEMS): Claim 7 A method for verifying the detection of a Karman line intersection, wherein, in claim 1, the portable object further comprises an angular velocity sensor; and the reliability index is defined by a function given for angular velocity measurements performed by the angular velocity sensor during the detection phase of the detection method, or performed periodically. Claim 8 A method for verifying the detection of a Karman line intersection according to claim 7, characterized in that the reliability index is defined by the following function: In the equation, C3(M) is the reliability index for the M angular velocity measurements taken, and W k is the value of the angular velocity provided by the angular velocity sensor during the k-th angular velocity measurement or calculated by the electronic unit based on the k-th measurement, where K = 1 to M, and the value L3 is the value W k There is a given constraint on , and the function δ provides a value '1' if the condition it is associated with is true and a value '0' if this condition is false, and thus C3(M) has a value between '0' and '1'. Claim 9 A method for verifying the detection of a Karman line intersection according to claim 8, characterized in that the given condition is satisfied when the reliability index is greater than a reference value (R2), which is selected between '0.5' and '1' or from '0.7' to '0.9'. Claim 10 A method for verifying the detection of a Karman line intersection, wherein, in any one of claims 2 to 4, the portable object further comprises an angular velocity sensor; and the method for verification is defined by a given function for angular velocity measurements performed by the angular velocity sensor or periodically performed during the detection phase of the method for detecting the Karman line intersection, and calculates another reliability index that proves at least one condition given for another reliability index, thereby verifying or not verifying the detection of the Karman line intersection by the portable object. Claim 11 A method for verifying the detection of Karman line intersections according to claim 10, characterized in that the additional reliability index is defined by the following function: In the equation, C3(M) is an additive reliability index for the M angular velocity measurements taken, and W k is the value of the angular velocity provided by the angular velocity sensor during the k-th angular velocity measurement or calculated by the electronic unit based on the k-th measurement, where K = 1 to M, and the value L3 is the value W k A given constraint on , and the function δ provides a value '1' if the condition it is associated with is true and a value '0' if this condition is false, and thus C3(M) has a value between '0' and '1'. Claim 12 A method for verifying the detection of a Karman line intersection according to claim 11, characterized in that when the additional reliability index is greater than a second reference value (R2) selected between '0.5' and '1' or from '0.7' to '0.9', a given condition for the additional reliability index is satisfied. Claim 13 A method for verifying the detection of a Karman line crossing, characterized in that, in any one of claims 7 to 9, the angular velocity sensor is formed by a microelectromechanical system (MEMS). Claim 14 A portable object (2) that is portable by a user and comprises a detection device formed by an acceleration sensor (8), a time base, and an electronic unit (12), wherein the detection device is arranged to measure or periodically measure the accelerations of the portable object by the acceleration sensor (8); wherein the detection device is arranged to autonomously detect the crossing of a Kármán line, defined by a predetermined altitude, by the portable object by processing acceleration measurements performed at least during the space flight of the rocket in the electronic unit; and wherein the detection device forms part of a detection and verification device (6) which is also arranged to implement a method for verifying the detection of the crossing of a Kármán line by the portable object described in claim 1, and wherein the time base is used to continuously determine a period for measuring the acceleration. Claim 15 In claim 14, the portable object (2) is characterized in that the acceleration sensor (8) is formed by a microelectromechanical system (MEMS). Claim 16 In claim 14, the detection and verification device (6) further comprises an angular velocity sensor (10); and the electronic unit (12) is arranged to enable the implementation of a method for verifying the detection of the intersection of Karman lines by the portable object described in any one of claims 7 to 9, characterized in that the portable object (2). Claim 17 In claim 15, the detection and verification device (6) further comprises an angular velocity sensor (10); and the electronic unit (12) is arranged to enable the implementation of a method for verifying the detection of a Karman line intersection by a portable object described in any one of claims 7 to 9, characterized in that the portable object (2). Claim 18 In claim 16, the portable object (2) is characterized in that the angular velocity sensor (10) is formed by a microelectromechanical system (MEMS). Claim 19 In claim 17, the portable object (2) is characterized in that the angular velocity sensor (10) is formed by a microelectromechanical system (MEMS). Claim 20 A portable object (2) characterized in that, in claim 14 or 15, the portable object is a watch (2).

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