Mounting platform for handling at least one aircraft underbody without deformation for mounting an aircraft fuselage

Description

Technical field

[0001] The present invention relates to an assembly platform for manipulating at least one lower aircraft shell for assembly of a fuselage body, while maintaining the shape of the lower shell. State of the art

[0002] An aircraft fuselage barrel typically comprises several components, including a cabin floor grid, a lower shell, two side shells, and an upper shell. These components are manufactured independently of each other, and the holes for joining them are drilled before assembly. Assembling these components therefore requires hole-to-hole assembly and / or part-to-part assembly techniques to ensure they are properly aligned during assembly. Documents US 2022 / 097870 A1, CN 102 001 451 B, CN 104 229 158 B and EP 2 979 810 A1 describe installation systems for assembling a fuselage.

[0003] As for the lower hull, its shape must be maintained during assembly. This is because the lower hull can deform during assembly. For example, it can twist. This can be a disadvantage during fuselage body assembly. Statement of the invention

[0004] The present invention aims to overcome this drawback. To this end, it relates to an assembly platform intended to manipulate at least one lower hull of an aircraft with a view to assembling a fuselage body of the aircraft.

[0005] According to the invention, the assembly platform comprises at least: a rectangular chassis having a longitudinal axis and four corners, at least two frames having a longitudinal axis, the at least two frames having an adjustable attitude relative to the rectangular chassis, at least two adjustment systems associated with a frame, the at least two adjustment systems being intended to adjust the attitude of the frame with which it is associated relative to the rectangular chassis, at least two cradles, each of the at least two cradles being fixed to a frame, the at least two cradles having a generating line parallel to the longitudinal axis of the frame on which it is fixed, the at least two cradles each having at least one receiving surface intended to receive the lower shell and to maintain the lower shell in a desired shape, each of the two frames comprising an alignment arm extending parallel to the longitudinal axis of each of the two frames,the alignment arm of each of the two frames comprising a free end comprising a centering pin, the centering pin of the alignment arm being intended to receive a positioning element of the lower hull.

[0006] According to one feature, the receiving surface(s) of each of the at least two cradles comprise a plurality of rigid pads intended to serve as support for the lower shell on each of the at least two cradles, the plurality of rigid pads being configured so that the lower shell is maintained in the desired shape when the lower shell rests on the plurality of rigid pads.

[0007] According to another feature, the receiving surface(s) each comprise at least one fixing device intended to fix the lower shell to the two cradles.

[0008] Furthermore, the fixing device(s) for the receiving surface(s) each correspond to a suction cup fixed to the receiving surface(s).

[0009] In addition, each of the at least two cradles comprises at least one first support structure comprising a first receiving area of ​​a first lateral side of the cradle and at least one second support structure forming comprising a second receiving area of ​​a second lateral side of the cradle, the first receiving area and the second receiving area of ​​each of the at least two cradles forming a receiving surface, the first support structure(s) and the second support structure(s) of each of the at least two cradles being rotatably mounted about an axis of rotation parallel to the longitudinal axis of the frame, each of the at least two cradles comprising at least one first damping device each associated with a first support structure and at least one second damping device each associated with a second support structure, the first damping device(s) being configured to bring the associated first support structure(s) to a nominal position about the axis of rotation parallel to the longitudinal axis of the frame on which the cradle is fixed, the second damping device(s) being configured to bring the associated second support structure(s) to a nominal position about the axis of rotation parallel to the longitudinal axis of the frame on which the cradle is fixed.

[0010] Furthermore, the first receiving area of ​​the first support structure(s) of each of the at least two cradles comprises a first sliding hoop and the second receiving area of ​​the second support structure(s) of each of the at least two cradles comprises a second sliding hoop, the first sliding hoop having a first curved longitudinal axis between two longitudinal ends of the first sliding hoop, the first curved longitudinal axis conforming to the first receiving zone, the second sliding hoop having a second curved longitudinal axis between two longitudinal ends of the second sliding hoop, the second curved longitudinal axis conforming to the second receiving zone, the first sliding hoop being configured to slide along the first curved longitudinal axis in a first curved slide of the first support structure(s) of each of the at least two cradles, the second sliding hoop being configured to slide along the second curved longitudinal axis in a second curved slide of the second support structure(s) of each of the at least two cradles,the first curved slide comprising a spring element at each longitudinal end of the first sliding hoop for bringing the first sliding hoop into a nominal position, the second curved slide comprising a spring element at each longitudinal end of the second sliding hoop for bringing the second sliding hoop into a nominal position.

[0011] Furthermore, each of the at least two adjustment systems comprises two adjustment devices, the two adjustment devices being fixed to the frame to which the adjustment system is associated on either side of the longitudinal axis of the frame in line with the cradle, the two adjustment devices also being fixed to the rectangular chassis, each of the two adjustment devices of the at least two adjustment systems being configured to adjust a distance between the rectangular chassis and the frame.

[0012] Furthermore, the assembly platform comprises four alignment masts each comprising a top arranged to receive an aircraft side hull positioning reference device, one alignment mast being fixed to each of the four corners and perpendicular to the rectangular chassis.

[0013] In an alternative embodiment, the assembly platform further comprises at least two support masts, each comprising a top arranged to receive a device for positioning the side shells, each of the two support masts being fixed perpendicular to the rectangular chassis between two alignment masts on a longitudinal edge of the rectangular chassis.

[0014] In addition, each of the at least two support masts has an end opposite the top rotatably mounted about an axis perpendicular to the longitudinal axis of the rectangular frame so that each of the at least two support masts is alternately in a retracted position in which each of the at least two support masts is substantially parallel to the rectangular frame and in a deployed position in which each of the at least two support masts is substantially perpendicular to the rectangular frame.

[0015] Furthermore, the assembly platform further comprises a device for balancing the assembly platform intended to keep the rectangular chassis substantially horizontal, the balancing device comprising adjustable feet on which the rectangular chassis is fixed, the adjustable feet being vertically adjustable in height, the adjustable feet being intended to be placed on the ground, the adjustable feet being arranged at the four corners of the rectangular chassis.

[0016] Furthermore, the rectangular frame comprises at least one housing intended to receive a handling fork parallel to the rectangular frame in order to move the assembly platform from one location to another. Brief description of the figures

[0017] The attached figures will make it clear how the invention can be implemented. In these figures, identical references designate similar elements. The figure 1represents a perspective view of an assembly platform according to one embodiment. The figure 2 represents a perspective view of an assembly platform receiving a lower shell of an aircraft fuselage body. The figure 3 represents a perspective view of a detail of a cradle of an assembly platform. The figure 4 represents a perspective view of an alignment arm of an assembly platform. The Figure 5 represents a front view of a longitudinal edge of an assembly platform. The figure 6 represents a top view of a cradle of an assembly platform. The figure 7 represents a schematic profile view of an aircraft comprising a fuselage body. The figure 8 represents a schematic profile view of a detail of the assembly platform including a jack device. Detailed description

[0018] Assembly platform 1 is shown in the figure 1and on the figure 2 The assembly platform 1 is intended to handle at least one lower hull 2 ​​of an AC aircraft with a view to assembling a fuselage body 3 of the AC aircraft.

[0019] In the description, a "central plane of symmetry" of an object is a plane that cuts the object into two equal parts in a longitudinal direction of the object. The adjective "lateral" qualifies a part that is located on one side or / and the other of the central plane of symmetry without intersecting the central plane of symmetry.

[0020] The longitudinally opposite ends of an object are called the "longitudinal ends" of the object.

[0021] The adjective "vertical" and the adverb "vertically" refer to the direction of gravity. The adjective "horizontal" and the adverb "horizontally" refer to a direction perpendicular to the direction of gravity.

[0022] Furthermore, the adjectives "upper" and "lower" are defined in relation to the ground over which the transport system 1 is likely to be moved. An object qualified by the adjective "lower" is located closer to the ground than an object qualified by the adjective "higher".

[0023] The assembly platform 1 comprises at least one rectangular frame 4 having a longitudinal axis A1 and four corners C1, C2, C3, C4.

[0024] The assembly platform 1 also comprises at least two frames 5 having an adjustable angle relative to the rectangular chassis 4.

[0025] In the remainder of the description, the expression “at least two frames” is omitted from the remainder of the description, but it is understood that the assembly platform 1 may also comprise more than two frames 5.

[0026] Each of the two frames 5 comprises a longitudinal axis A2.

[0027] The assembly platform P further comprises at least two cradles 6. In the embodiment shown in the figure 1 , the assembly platform 1 comprises two cradles 6.

[0028] In the remainder of the description, the expression “at least two cradles” is omitted, but it is understood that the assembly platform 1 may also comprise more than two cradles 6.

[0029] Each of the two cradles 6 is fixed on a frame 5.

[0030] The assembly platform also includes at least two adjustment systems 8 each associated with a frame 5 ( figure 6 ). In other words, each adjustment system 8 is associated with a different frame 5.

[0031] In the remainder of the description, the expression “at least two adjustment systems” is omitted from the remainder of the description, but it is understood that the assembly platform 1 may also comprise more than two adjustment systems 8.

[0032] Each of the two adjustment systems 8 is intended to adjust the attitude of the frame 5 with which it is associated relative to the rectangular chassis 4.

[0033] According to one embodiment, each of the two adjustment systems 8 comprises two adjustment devices 13. The two adjustment devices 13 are fixed to the frame 5 with which the adjustment system 8 is associated. The two adjustment devices 13 of an adjustment system 8 are arranged on either side of the longitudinal axis A2 of the frame 5 in line with the cradle 6. The two adjustment devices 13 are also fixed to the rectangular chassis 4. Each of the two adjustment devices 13 of the two adjustment systems 8 is configured to adjust a distance between the rectangular chassis 4 and the frame 5.

[0034] For example, each of the two adjustment devices 13 comprises a hydraulic cylinder 131. The hydraulic cylinder 131 of each of the two adjustment devices 13 has a first end fixed to the rectangular chassis and a second end fixed to the frame 5. For example, the second end is fixed to a side edge of the frame 5. Thus, a hydraulic cylinder 131 is able to adjust a distance between a side edge of the frame 5 and the rectangular chassis 4.

[0035] Each of the two cradles 6 has a cradle surface having a generating line D parallel to the longitudinal axis A2 of the frame 5 on which it is fixed. A generating line of a cradle surface corresponds to a line which moves parallel to itself in space along a curve (the curve defining the curvature of the cradle surface), in a constant direction. A generating line D corresponds to this line at any location along the curve of the cradle surface.

[0036] Furthermore, the two cradles 6 have a central plane of symmetry (along an axis parallel to the generating line D) which is substantially merged with a central plane of symmetry P of the assembly platform.

[0037] The two cradles 6 each have at least one receiving surface 7 corresponding to the cradle surface intended to receive the lower shell 2 and to maintain the lower shell 2 in a desired lower shell 2 shape. The receiving surface(s) 7 of each of the two cradles 6 may comprise a plurality of rigid pads 10 intended to serve as a support for the lower shell 2 on each of the two cradles 6 ( figure 3). The plurality of rigid pads 10 are configured so that the lower shell 2 is maintained in the desired shape when the lower shell 2 rests on the plurality of rigid pads 10. The plurality of rigid pads 10 determines the desired shape of the lower shell 2. The pads 10 of the plurality of pads 10 are adjustable in position before the first receipt of the lower shell 2. A periodic check of the plurality of pads 10 may be performed. For example, the check may be performed a predetermined number of times per year or after a predetermined number of AC aircraft are assembled.

[0038] The receiving surface(s) 7 may each comprise at least one fixing device 11 intended to fix the lower shell 2 to the two cradles 6. When it is said that the fixing device(s) 11 are intended to fix the lower shell 2 to the two cradles 6, it is meant that the fixing device(s) 11 hold the lower shell 2 on the two cradles 6 without there being any relative movement between the lower shell 2 and the receiving surface 7 of the two cradles 6.

[0039] Advantageously, the fixing device(s) 11 of the receiving surface(s) 7 each correspond to a suction cup fixed to the receiving surface(s) 7 ( figure 3 ).

[0040] Furthermore, each of the two cradles 6 comprises at least one first support structure S1 comprising a first receiving zone Z1 of a first lateral side L1 of cradle 6 and at least one second support structure S2 comprising a second receiving zone Z2 of a second lateral side L2 of cradle 6. The first receiving zone Z1 and the second receiving zone Z2 of each of the two cradles 6 together form a receiving surface 7. The first support structure(s) S1 is(are) symmetrical to the second support structure(s) S2 with respect to a central plane of symmetry P of the assembly platform 1.

[0041] As illustrated in the figure 1 and the figure 6 , in one embodiment, each of the cradles 6 comprises two first support structures S1 and two second support structures S2.

[0042] The first support structure(s) S1 and the second support structure(s) S2 of each of the two cradles 6 are rotatably mounted relative to the frame 5 around an axis of rotation A3 parallel to the longitudinal axis A2 of the frame 5 ( figure 4 ).

[0043] Each of the two cradles 6 may comprise at least one first U-shaped fixing element 30 fixed to the frame 5 and at least one second U-shaped fixing element 31 fixed to the frame 5. The first U-shaped fixing element(s) 30 and the second U-shaped fixing element(s) 31 each comprise two parallel legs supporting an axis of rotation coinciding with the axis of rotation A3.

[0044] The or each of the first U-shaped fixing elements 30 is associated with a first support structure S1. The or each of the second U-shaped fixing elements 31 is associated with a second support structure S2.

[0045] The or each of the first support structures S1 of each of the two cradles 6 is rotatably mounted between the two legs of a first U-shaped fixing element 30. The or each of the second support structures S2 of each of the two cradles 6 is rotatably mounted between the two legs of a second U-shaped fixing element 31.

[0046] In one embodiment, each of the first U-shaped fixing elements 30 and each of the second U-shaped fixing elements 31 comprises a displacement part 36. This displacement part 36 allows each of the first U-shaped fixing elements 30 and each of the second U-shaped fixing elements 31 to move according to a translational movement 371 perpendicular to the axis of rotation A3 and a translational movement 372 parallel to the axis of rotation A3. On the figure 3, the translational movement 371 and the translational movement 372 are represented by a double arrow. The displacement part 36 may correspond to a ball bearing plate.

[0047] Each of the two cradles 6 comprises at least one first damping device D1 and at least one second damping device D2. The or each of the first damping devices D1 is associated with a first support structure S1. The or each of the second damping devices D2 is associated with a second support structure S2.

[0048] The first damping device(s) D1 are configured to bring the associated first support structure(s) S1 to a nominal position around the rotation axis A3 parallel to the longitudinal axis A2 of the frame 5 on which the cradle 6 is fixed. Similarly, the second damping device(s) D2 are configured to bring the associated second support structure(s) S2 to a nominal position around the rotation axis A3 parallel to the longitudinal axis A2 of the frame 5 on which the cradle 6 is fixed. The nominal position of the support structures S1 and S2 corresponds to a position in which the support structures S1 and S2 are not stressed by a force, in particular when the lower shell 2 is not received on the cradles 6.

[0049] In one embodiment ( figure 6), the or each of the first damping devices D1 comprises a first end 32 fixed to a first U-shaped fixing element 30 and a second end 33 fixed to the associated first support structure S1. The or each of the second damping devices D2 comprises a first end 34 fixed to a second U-shaped fixing element 31 and a second end 35 fixed to the associated second support structure S2.

[0050] The first receiving zone Z1 of the first support structure(s) S1 of each of the two cradles 6 may comprise a first sliding hoop B1. Similarly, the second receiving zone Z2 of the second support structure(s) S2 of each of the two cradles 6 may comprise a second sliding hoop B2.

[0051] The first sliding arch B1 has a first curved longitudinal axis A41 between its two longitudinal ends E1. The first curved longitudinal axis A41 conforms to the first receiving zone Z1. Similarly, the second sliding arch B2 has a second curved longitudinal axis A42 between its two longitudinal ends E2. The second curved longitudinal axis A42 conforms to the second receiving zone Z2.

[0052] The first sliding arch B1 is configured to slide along the first curved longitudinal axis A41 in a first curved slide R1 of the first support structure(s) S1 of each of the two cradles 6. Similarly, the second sliding arch B2 is configured to slide along the second curved longitudinal axis A42 in a second curved slide R2 of the second support structure(s) S2 of each of the two cradles 6.

[0053] A slide corresponds to a groove made in the support structures S1 and S2 to slide the sliding hoops B1 and B2.

[0054] The first curved slide R1 of the first support structure(s) S1 of each of the two cradles 6 has a longitudinal axis parallel to the first curved longitudinal axis A41. The second curved slide R2 of the second support structure(s) S2 of each of the two cradles 6 has a longitudinal axis parallel to the second curved longitudinal axis A42.

[0055] The first curved slide R1 comprises a spring element 12 at each longitudinal end E1 of the first sliding arch B1. The spring element 12 at each end of the first sliding arch B1 exerts a force parallel to the first curved longitudinal axis A41 to bring the first sliding arch B1 into a nominal position. Similarly, the second curved slide R2 comprises a spring element 12 at each longitudinal end E2 of the second sliding arch B2. The spring element 12 at each end of the second sliding arch B2 exerts a force parallel to the second curved longitudinal axis A42 to bring the second sliding arch B2 into a nominal position. The nominal position of the sliding arches B1 and B2 corresponds to a position in which the sliding arches B1 and B2 are not stressed by a force, in particular when the lower shell 2 is not received on the cradles 6.

[0056] On the embodiment illustrated on the figure 6 , the spring element 12 of the ends of the first sliding arch(s) B1 and the ends of the second sliding arch(s) B2 comprises two helical springs 121 having a longitudinal axis parallel to the first curved longitudinal axis A41 and to the second curved longitudinal axis A42, respectively. The spring element 12 may also comprise a helical spring guide rod 121. The guide rod has a longitudinal axis parallel to the first curved longitudinal axis A41 and to the second curved longitudinal axis A42, respectively. A guide rod may be screwed by a screwing element 122 to each of the ends E1, E2 of the slides R1 and R2. The fixing device(s) 11 (for example the suction cups) and / or the plurality of rigid pads 10 are fixed on the first sliding arch B1 and the second sliding arch B2.

[0057] Furthermore, the assembly platform 1 comprises four alignment masts 14 each comprising a top 15 arranged to receive a reference device 16 for positioning the aircraft side hull AC. An alignment mast 14 is fixed to each of the four corners C1, C2, C3, C4. Each of the alignment masts 14 has a longitudinal axis perpendicular to the rectangular chassis 4.

[0058] For example, the positioning reference device 16 corresponds to a device intended to position relative to each other at least one cabin floor grid (not shown) and two side shells (not shown) of an aircraft AC with a view to assembling a fuselage body 3 of the aircraft AC.

[0059] Advantageously, the assembly platform 1 may further comprise at least two support masts 17 each comprising a top 25 arranged to receive a fixing device to which the side shells are fixed. Each of the two support masts 17 is fixed perpendicular to the rectangular chassis 4 between two alignment masts 14 on a longitudinal edge LA1, LA2 of the rectangular chassis 4.

[0060] The presence or absence of the support masts 17 may depend on the length of the fuselage body 3 to be assembled. Indeed, the presence of the support masts 17 may be necessary if the length of the fuselage body 3 to be assembled has a length that may cause bending of the cabin floor grid and / or of the two side shells between the alignment masts 14 under their own mass.

[0061] In addition, each of the at least two support masts 17 has an end 19 opposite the top 25 rotatably mounted about an axis A5 perpendicular to the longitudinal axis A1 of the rectangular chassis 4 so that each of the at least two support masts 17 is alternately in a retracted position and a deployed position. In the retracted position, each of the at least two support masts 17 is substantially parallel to the rectangular chassis 4. In the deployed position, each of the at least two support masts 17 is substantially perpendicular to the rectangular chassis 4. On the figure 1 and the figure 2 , the support masts 17 are in the deployed position.

[0062] As shown in the figure 1 and the figure 2 , the rectangular frame 4 may also comprise at least two housings 24. Each of the two housings 24 is intended to house a support mast 17 when this support mast 17 is in the retracted position.

[0063] As shown in the figure 1 and the figure 8 , each of the at least two support masts 17 may further comprise a jack device 26. The jack device 26 is configured to drive the support mast 17 from the retracted position to the deployed position and vice versa around the axis A5 perpendicular to the longitudinal axis A1 of the rectangular chassis 4. For example, the jack device 26 is fixed to the end 19. On the figure 1 , a jack device 26 is shown transparently under the rectangular chassis 4. For the sake of clarity of the figure 1 , only a jack device 6 is shown.

[0064] On the figure 8 , the translational drive movement 261 (represented by a double arrow 261 on the figure 8) generated by the jack device 26 causes a rotational movement 171 (represented by a double arrow 171) of the support mast 17 around the axis A5 at the end 19.

[0065] Furthermore, as shown in the figure 1 and the figure 2 , each of the support masts 17 may comprise a crutch 27 configured to maintain each of the support masts 17 in a position substantially perpendicular to the rectangular frame 4. The crutch 27 of each of the support masts 17 comprises an end fixed to the rectangular frame 4 and an end fixed to the support mast 17 between the end 19 and the top 25.

[0066] Furthermore, the assembly platform 1 may comprise a balancing device 9 of the assembly platform 1 ( Figure 5). The balancing device 9 is intended to keep the rectangular frame 4 substantially horizontal. The balancing device 9 may comprise adjustable feet 18 on which the rectangular frame 4 is fixed. The adjustable feet 18 are vertically adjustable in height. The adjustable feet 18 are intended to be placed on the ground. The adjustable feet 18 are arranged at the four corners C1, C2, C3, C4 of the rectangular frame 4.

[0067] Each of the adjustable feet 18 may include a jack for adjusting their height. For example, the jack of each of the adjustable feet 18 may correspond to a hydraulic jack that can be controlled remotely.

[0068] Each of the adjustable feet 18 may also correspond to an adjustable foot by screwing or unscrewing. For example, unscrewing allows the height of the adjustable foot 18 to be increased and screwing allows the height of the adjustable foot 18 to be decreased.

[0069] Each of the two frames 5 comprises a centering pin 22. The centering pin 22 of each of the two frames 5 is intended to receive a positioning element of the lower shell 2. This centering pin 22 makes it possible to place the lower shell 2 on the assembly platform 1 so that the longitudinal axis of the lower shell 2 is substantially parallel to the longitudinal axis A1 of the rectangular chassis 4.

[0070] According to the claimed invention, each of the two frames 5 comprises an alignment arm 20 extending parallel to the longitudinal axis A2 of each of the two frames 5. The alignment arm 20 has a free end 21 comprising a centering pin 22 ( figure 4 ).

[0071] This centering pin 22 is intended to receive a positioning element of the lower shell 2. This positioning element of the lower shell 2 may correspond to an element having a shape complementary to the shape of the centering pin 22. This centering pin 22 makes it possible to place the lower shell 2 on the assembly platform 1 so that the longitudinal axis of the lower shell 2 is substantially parallel to the longitudinal axis A1 of the rectangular chassis 4.

[0072] For example, the centering pin 22 of one of the two frames 5 and the centering pin 22 of the other of the two frames 5 are aligned along a line parallel to the longitudinal axis A1 of the rectangular chassis 4.

[0073] According to one embodiment ( Figure 5), the rectangular frame 4 may comprise at least one housing 23 intended to receive a handling fork parallel to the rectangular frame 4 in order to move the assembly platform 1 from one location to another.

[0074] According to another embodiment, the assembly platform may comprise wheels (not shown) mounted under the rectangular frame 4 in order to move the assembly platform 1 from one location to another. These wheels may be retractable.

Claims

1. An assembly platform (1) intended for manipulating at least one lower shell (2) of an aircraft (AC) in order to assemble a fuselage barrel (3) of the aircraft (AC), wherein it comprises at least: - a rectangular chassis (4) having a longitudinal axis (A1) and four corners (C1, C2, C3, C4), - at least two frames (5) having a longitudinal axis (A2), the at least two frames (5) having a trim that is adjustable with respect to the rectangular chassis (4), - at least two setting systems (8) associated with a frame (5), the at least two setting systems (8) being intended to adjust the trim of the frame (5) with which it is associated with respect to the rectangular chassis (4), - at least two cradles (6), each of the at least two cradles (6) being fixed onto a frame (5), the at least two cradles (6) having a generating line (D) parallel to the longitudinal axis (A2) of the frame (5) to which it is fixed, the at least two cradles (6) each having at least one reception surface (7) intended to receive the lower shell (2) and to hold the lower shell (2) in a desired form; characterized in that each of the two frames (5) comprises an alignment arm (20) extending parallel to the longitudinal axis (A2) of each of the two frames (5), the alignment arm (20) of each of the two frames (5) comprising a free end (21) comprising a centering pin (22), the centering pin (22) of the alignment arm (20) being intended to receive a positioning element of the lower shell (2).

2. The platform as claimed in claim 1, characterized in that the reception surface or surfaces (7) of each of the at least two cradles (6) comprise a plurality of rigid pads (10) intended to serve as bearing support for the lower shell (2) on each of the at least two cradles (6), the plurality of the rigid pads (10) being configured for the lower shell (2) to be held in the desired form when the lower shell (2) is pressed onto the plurality of the rigid pads (10).

3. The platform as claimed in either one of claims 1 and 2, characterized in that the reception surface or surfaces (7) each comprise at least one fixing device (11) intended to fix the lower shell (2) to the two cradles (6).

4. The platform as claimed in claim 3, characterized in that the fixing device or devices (11) of the reception surface or surfaces (7) each correspond to a sucker fixed onto the reception surface or surfaces (7).

5. The platform as claimed in either one of claims 1 to 4, characterized in that each of the at least two cradles (6) comprises at least one first support structure (S1) comprising a first reception zone (Z1) for a first lateral side (L1) of a cradle (6) and at least one second support structure (S2) comprising a second reception zone (Z2) for a second lateral side (L2) of a cradle (6), the first reception zone (Z1) and the second reception zone (Z2) of each of the at least two cradles (6) forming a reception surface (7), the first support structure or structures (S1) and the second support structure or structures (S2) of each of the at least two cradles (6) being mounted to rotate about a rotation axis (A3) parallel to the longitudinal axis (A2) of the frame (5), each of the at least two cradles (6) comprising at least one first damping device (D1) each associated with a first support structure (S1) and at least one second damping device (D2) each associated with a second support structure (S2), the first damping device or devices (D1) being configured to bring the associated first support structure or structures (S1) to a nominal position about the rotation axis (A3) parallel to the longitudinal axis (A2) of the frame (5) to which the cradle (6) is fixed, the second damping device or devices (D2) being configured to bring the associated second support structure or structures (S2) to a nominal position about the rotation axis (A3) parallel to the longitudinal axis (A2) of the frame (5) to which the cradle (6) is fixed.

6. The platform as claimed in claim 5, characterized in that the first reception zone (Z1) of the first support structure or structures (S1) of each of the at least two cradles (6) comprises a first sliding half-ring (B1) and the second reception zone (Z2) of the second support structure or structures (S2) of each of the at least two cradles (6) comprises a second sliding half-ring (B2), the first sliding half-ring (B1) having a first curved longitudinal axis (A41) between two longitudinal ends (E1) of the first sliding half-ring (B1), the first curved longitudinal axis (A41) being in accordance with the first reception zone (Z1), the second sliding half-ring (B2) having a second curved longitudinal axis (A42) between two longitudinal ends (E2) of the second sliding half-ring (B2), the second curved longitudinal axis (A42) being in accordance with the second reception zone (Z2), the first sliding half-ring (B1) being configured to slide along the first curved longitudinal axis (A41) in a first curved slide (R1) of the first support structure or structures (S1) of each of the at least two cradles (6), the second sliding half-ring (B2) being configured to slide along the second curved longitudinal axis (A42) in a second curved slide (R2) of the second support structure or structures (S2) of each of the at least two cradles (6), the first curved slide (R1) comprising a spring element (12) at each longitudinal end (E1) of the first sliding half-ring (B1) to bring the first sliding half-ring (B1) into a nominal position, the second curved slide (R2) comprising a spring element (12) at each longitudinal end (E2) of the second sliding half-ring (B2) to bring the second sliding half-ring (B2) into a nominal position.

7. The platform as claimed in any one of claims 1 to 6, characterized in that each of the at least two setting systems (8) comprises two setting devices (13), the two setting devices (13) being fixed to the frame (5) with which the setting system (8) is associated on either side of the longitudinal axis (A2) of the frame (5) in line with the cradle (6), the two setting devices (13) being also fixed to the rectangular chassis (4), each of the two setting devices (13) of the at least two setting systems (8) being configured to adjust a distance between the rectangular chassis (4) and the frame (5).

8. The platform as claimed in any one of claims 1 to 6, characterized in that it comprises four alignment posts (14) each comprising a top (15) arranged to receive a referential positioning device (16) of an aircraft side shell, an alignment post (14) being fixed at each of the four corners (C1, C2, C3, C4) and at right angles to the rectangular chassis (4).

9. The platform as claimed in any one of claims 1 to 8, characterized in that it comprises at least two support posts (17) each comprising a top (25) arranged to receive a positioning device for the side shells, each of the two support posts (17) being fixed at right angles to the rectangular chassis (4) between two alignment posts (14) on a longitudinal edge (LA1, LA2) of the rectangular chassis (4).

10. The platform as claimed in claim 8, characterized in that each of the at least two support posts (17) has an end (19) opposite the top (25) mounted to rotate about an axis (A5) at right angles to the longitudinal axis (A1) of the rectangular chassis (4) in such a way that each of the at least two support posts (17) alternately takes a retracted position in which each of the at least two support posts (17) is substantially parallel to the rectangular chassis (4) and a deployed position in which each of the at least two support posts (17) is substantially at right angles to the rectangular chassis (4).

11. The platform as claimed in any one of claims 1 to 9, characterized in that it further comprises a balancing device (9) for the assembly platform (1) intended to hold the rectangular chassis (4) substantially horizontal, the balancing device (9) comprising adjustable feet (18) to which the rectangular chassis (4) is fixed, the adjustable feet (18) being adjustable vertically in height, the adjustable feet (18) being intended to be placed on the ground, the adjustable feet (18) being disposed at the four corners (C1, C2, C3, C4) of the rectangular chassis (4).

12. The platform as claimed in any one of claims 1 to 11, characterized in that the rectangular chassis (4) comprises at least one housing (23) intended to receive a handling fork parallel to the rectangular chassis (4) in order to move the assembly platform (1) from one place to another.