Vehicle body

1. A method for forming a vehicle body, comprising:

forming a rigid tub;

mating the rigid tub to a first mould for a superstructure of the vehicle body; and subsequently

rigidifying material in the first mould whilst part of that material is in contact with the tub to thereby form the superstructure of the vehicle body integral with the tub, said material comprising a superstructure portion and a bonding portion integral with the superstructure portion and in contact with the tub,

wherein the first mould comprises a flexible portion where the bonding portion overlaps the tub and the rigidifying step comprises causing the flexible portion to flex so as to bear against at least part of the bonding portion; and a non-flexible portion with a surface that defines the shape of at least part of the superstructure portion where the superstructure portion does not overlap the tub.

2. A method as claimed in claim 1 , wherein the step of mating the rigid tub to the first mould comprises locating the tub to the first mould by aligning a datum feature on the tub with a datum feature on the first mould.

3. A method as claimed in claim 2 , comprising, after the said rigidifying step, attaching a component of the vehicle to the tub with the datum feature on the tub aligned with a datum feature on the component.

4. A method as claimed in claim 3 , wherein the component is a part of at least one of a running gear or a powertrain of the vehicle.

5. A method as claimed in claim 1 , wherein the said material is a fibre-reinforced material and fibres of the material extend between the superstructure portion and the bonding portion.

6. A method as claimed in claim 1 , wherein:

the flexible portion comprises a distal region and a proximal region located between the distal region and the superstructure portion, and the distal region has greater freedom of movement than the proximal region.

7. A method as claimed in claim 1 , wherein the rigidifying step comprises applying pressure to the flexible portion to consolidate the bonding portion against the tub.

8. A method as claimed in claim 7 , wherein following the rigidifying step the bonding portion is thinner at an end remote from the superstructure portion than at an end proximal to the superstructure portion.

9. A method as claimed in claim 1 , wherein:

the step of forming a rigid tub comprises:

pressing a hollow body of material against the interior of a second mould by means of an inflatable core located within the hollow body;

rigidifying the hollow body with the inflatable core located therein so as to form at least part of the tub; and

keeping the inflatable core in the hollow body of the tub until the said step of rigidifying material in the first mould; and

the step of rigidifying material in the first mould comprises applying pressure against the first mould by means of the inflatable core.

10. A method as claimed in claim 1 , wherein:

the material of the superstructure is of a reinforced resin composite material;

the step of rigidifying material in the first mould comprises curing the resin; and

the superstructure is adhered to the tub by the resin.

11. A method as claimed in claim 1 , wherein, at an interface between the superstructure and the tub, the material of the superstructure bifurcates such that a first limb of the material extends in a first direction over the tub and a second limb of the material extends in a second direction over the tub, the angle between the first and second directions being between 45° and 135°.

12. A method for forming an integrated structure comprising first and second bodies, the method comprising

forming the first body in a rigid state; and

subsequently:

preparing a mould for the second body, the mould being mated to the first rigid body and the mould comprising a rigid first zone that does not overlap the first body and is adjacent to a first precursor material for the second body and a flexible second zone that overlaps the first body and is adjacent to a second precursor material for the second body;

applying pressure against the flexible zone to urge the second precursor material against the first body; and

rigidifying the first and the second precursor materials whilst the second precursor material is in contact with the first body.

13. A method as claimed in claim 12 , wherein the flexible second zone is anchored to the rigid first zone.

14. A method as claimed in claim 13 , wherein during the rigidifying step the flexible second zone is anchored to the rigid first zone at a boundary of the first body.

15. A method as claimed in claim 13 , wherein the flexible second zone is constituted by one or more flexible plates attached to the rigid first zone.

16. A method as claimed in claim 13 , wherein during the rigidifying step the flexible second zone has greater mobility relative to the first body at an end remote from the rigid first zone than at an end adjacent the rigid first zone.

17. A method as claimed in claim 12 , wherein the step of applying pressure comprises causing the second precursor material to adopt a tapering profile that becomes thinner towards an edge of the second precursor material remote from the first precursor material.

18. A method as claimed in claim 12 , wherein the precursor material comprises a resin matrix and a reinforcing component and the rigidifying step comprises bonding the second body to the first body by means of the resin comprised in the first and the second precursor materials.

19. A method as claimed in claim 12 , wherein the first body comprises an adhesive layer and wherein, during the step of rigidifying the first and the second precursor materials, the second precursor material is in contact with the adhesive layer of the first body.

20. A method as claimed in claim 12 , wherein the step of applying pressure comprises applying pressure by means of an inflatable flexible bag bearing against the flexible second zone.