GB2633398A

GB2633398A - Panel for a vehicle body

Info

Publication number: GB2633398A
Application number: GB2313776.3A
Authority: GB
Inventors: Santoni Claudio
Original assignee: Silverstone Performance Technologies Ltd
Current assignee: Silverstone Performance Technologies Ltd
Priority date: 2023-09-11
Filing date: 2023-09-11
Publication date: 2025-03-12
Also published as: GB202313776D0; WO2025056887A1

Abstract

An additively manufactured panel 10 for forming a vehicle body 24 has a first surface 12 and a second surface 14, with a support structure 16 between the first surface and the second surface. The first surface and the second surface have a contoured shape that enables the panel to be stacked. Also provided is a stack of panels arranged to minimise separation distance to maximise use of the build volume of a 3D printer, as well as a vehicle body and a production method. Panel 10 may be aluminium. The contour may comprise obtuse panels. The panel may have an air channel and a means of absorbing or generating sound, for example providing a Helmholtz resonator. The panel may also have two fluid channels and a means of exchanging heat between them.

Description

PANEL FOR A VEHICLE BODY FIELD OF THE INVENTION

The invention relates to vehicle bodies. In particular, the invention relates to additively manufactured panels for use in vehicle bodies.

BACKGROUND

Additive manufacturing can enable more finely tuned structural optimisation and greater design freedom when compared to conventional manufacturing. For example, cavities within structures can be produced without the use of a core, draft angles for removing a mould may not be required, and structures having thin walls of 0.1 mm or less can be produced with relative ease. It would therefore be desirable to use additive manufacturing to produce vehicle bodies.

One drawback is that additive manufacturing can be affected by a low rate of productivity, especially in laser sintering based additive manufacturing techniques. The maximum size of a part that can be 3D printed by a printer is limited by the build volume of the 3D printer. Thus, the relatively large size of most vehicle bodies compared to current build volumes means that it can take many printing batches to produce each vehicle body. Alternatively, a large number of 3D printers would be required to produce parts in parallel; however, this can be prohibitively expensive. These factors mean additive manufacturing can be impractical for producing vehicle bodies at scale.

It is an object of the invention to address these issues. SUMMARY OF INVENTION According to a first aspect of the invention, there is provided an additively manufactured panel for forming a vehicle body, comprising: a first surface and a second surface; and a support structure positioned between the first surface and the second surface; wherein the first surface and the second surface have a contoured shape that enables a plurality of like panels to be stacked together.

In this way, the plurality of similar panels can be stacked together in a repeating fashion within a build volume of a 3D printer, which is generally cuboidal in shape, such that a larger number of panels can be produced in each printing operation. This utilises a greater proportion of the build volume, providing increased manufacturing throughput. A vehicle body can be assembled in part or in whole from panels produced in this way.

Completely planar shapes may not be practical for many vehicle bodies. Therefore, some curvature of the panel is required. The contoured shape of the panel allows the panel to be used in contoured vehicle bodies while being stackable within a build volume of a 3D printer.

Sandwich panels can be produced by other means, such as by casting or joining surfaces to a support structure. However, casting the sandwich panels limits the type of structures that can be produced as the support structure. Joining surfaces to a support structure can be unsuitable for structural reasons. Additively manufacturing the panel enables complex support structures to be formed that are integral with the first surface and the second surface, which provides the most favourable combination of strength and design freedom.

Additionally, panels according to the first aspect of the invention can be used more easily by a human operator to design a vehicle body that can be additively manufactured efficiently while being compatible with other vehicle parts. For example, some computer-based design methods can dictate the shape of the vehicle body for maximum 3D printing efficiency. This limits design freedom for a human designer and can result in vehicle body shapes that are difficult to integrate with the rest of a vehicle.

The contoured shape may have curvature features arranged at obtuse angles with respect to a main longitudinal axis or plane of the panel.

The panel may configured for use in any part of a vehicle body. For example, the panel may be configured to be placed in a side portion or a corner portion of a vehicle body.

The panel can be suitable for any kind of vehicle body that provides a frame, such as an endoskeleton or an exoskeleton. The vehicle can be any kind of vehicle, for example a road vehicle such as a car or racing car, or any kind of manned or unmanned air vehicle.

The support structure can comprise a honeycomb structure, a grid structure, an irregular support structure, or any other kind of support structure, lattice or matrix that provides sufficient strength to allow the panel to be used in a vehicle body. The first surface, the second surface and the support structure form a sandwich panel configuration that is known to provide a particularly high-strength frame while remaining relatively lightweight. Additively manufacturing such a panel enables wall thicknesses to be reduced, further reducing vehicle weight without compromising the strength of the panel. Further, using additive manufacturing allows more complex structures to be used as the support structure. This allows different parts of the vehicle body to be more easily customised, for example to provide areas of higher or lesser stiffness to create protective or crumple zones, respectively. The support structure can also be solid in some regions to facilitate attachment of vehicle components.

The panel can be additively manufactured (or "3D printed") using any suitable additive manufacturing techniques and apparatus. In some examples, the panel is produced using powder bed fusion techniques, or laser sintering of metallic powder.

Preferably, the contoured shape comprises obtuse angles. The obtuse angles of the contoured shape enables a plurality of the panels to stack closely against one another to maximise the number of panels that can fit into a single build volume.

For example, curved, open shapes having obtuse angles tend to stack more closely together than shapes having acute angles, with its neighbouring panel. In this way, the first surface may be shaped so that it can be nested with the second surface of a neighbouring panel. This means that adjacent panels can be fitted to one another so that there is very little gap between them, which can make very efficient use of the build volume.

Preferably, the contoured shape comprises a substantially flat central portion and one or more curved edge portions that form a bend at an obtuse angle to the substantially flat central portion. In this way, the panel can be joined or assembled adjacent other similar panels while being stacked efficiently within a build volume of a 3D printer. In one example, the panel may have two opposing non-curved edges and two opposing curved edges that bend with respect to the central portion at obtuse angles.

Preferably, the panel comprises an air channel to an enclosed space between the first surface and the second surface, wherein the air channel and/or the enclosed space provide an acoustic mechanism configured to absorb or generate sound.

In this way, the panel can integrate functions of an acoustic component normally external to a vehicle body within the vehicle body. This provides weight savings while reducing the overall cost and production time of the vehicle. The air channel can be connected to an air-path, such as an exhaust system, of an internal combustion engine by a conduit to amplify the engine sound, in one specific example. In this way, the air channel and/or the enclosed space may form a resonator.

The air channel can be provided along one of the first or second surfaces. Alternatively, the air channel can be provided in the support structure, in which case the air channel may be configured to align and fluidically connect with an air channel of an adjacent panel in an assembled vehicle body. The enclosed space can be configured to trap air in order to reduce or dampen sound. Alternatively, the enclosed space can be configured to amplify or generate sound, depending on the structure of the enclosed space and the positioning of the air channel. The panel may be configured for performing an acoustic effect a particular frequency or frequency range.

The panel may comprise a plurality of air channels and a corresponding plurality of enclosed spaces to provide a more pronounced acoustic effect. The plurality of enclosed spaces may be configured to amplify or dampen different frequencies or frequency ranges.

Preferably, the air channel comprises one or more apertures on the first surface, and the air channel and the support structure are configured to provide a Helmholtz resonator. In this way, the functions of a Helmholtz resonator can be built into the vehicle body.

In some embodiments, the acoustic mechanism comprises a flexible membrane configured to generate sound. The flexible membrane can be part of the first and/or or second surface. Alternatively, the flexible membrane can be provided within or as part of the support structure.

Preferably, the panel comprises a first fluid inlet, a first fluid outlet, and a first fluid channel fluidically connecting the first fluid inlet to the first fluid outlet. In this way, the panel can be used as a heat exchanger. During use in a vehicle body, a fluid to be cooled, such as oil, can be passed through the first fluid channel and heat can be exchanged with the panel. The panel is connected to the remainder of the vehicle body, which provides a heat sink that can absorb and dissipate heat from the fluid. In this way, the panel can integrate functions of a heat exchanger component (normally external to a vehicle body) within the vehicle body. This provides weight savings, reduces the overall cost and production time of the vehicle.

Incorporating a heat exchange system into a vehicle body enables the heat exchanger to positioned away from the engine. Stress caused by vibration from the engine can cause heat exchangers to rupture and leak over time, ultimately causing engine failure. Placing the heat exchanger further from the engine reduces the vibrational stress on the heat exchanger, thereby improving the robustness of the vehicle.

The first fluid channel can be formed in the support structure in any suitable manner. The first fluid channel may comprise an internal porous support structure to prevent the presence of the first fluid channel from reducing the structural strength of the panel. Having an internal porous support structure also increases the surface area in contact between the panel and fluid to exchange heat more effectively with the panel. In other embodiments, the first fluid channel may be an open fluid channel that is not obstructed by an internal support structure.

Preferably, the panel further comprise a second fluid inlet, a second fluid outlet, and a second fluid channel fluidically connecting the second fluid inlet to the second fluid outlet, the second fluid channel arranged to exchange heat with the first fluid channel. In this way, a cooling fluid can be provided in the second fluid channel to allow greater cooling of a hot fluid in the first fluid channel.

The support structure can be arranged in a gyroid configuration to provide a separation wall between the two fluid channels.

Once installed in a vehicle body, several panels can be provided having fluid channels, where the fluid channels are at remote locations in the vehicle body. This can enable a hot fluid circulation zone within the vehicle body that is remote from a cold fluid circulation zone. In turn, this would enable more efficient 3D printing lattice geometries, more efficient fluid inlet/outlet location and full utilisation of structural heat sinking capability. In another configuration, the structure could be exposed to an inflow of external air to manage heat exchange with a fluid that circulate inside the structure.

Preferably, the first surface and/or the second surface have a maximum thickness of 4 mm or less, preferably 2mm or less, more preferably 1 mm or less. In this way, the panel is more lightweight to produce a lighter vehicle body.

Preferably, a separation distance between the first surface and the second surface is substantially constant across the panel. In this way, the stackability of the panel in a build volume is maximised.

The panel may have a contoured shape that enables two or more copies of the panel to be stacked in a build volume within 1 mm or less.

The panel may comprise a bonding feature configured to facilitate attachment to other panels. The bonding feature can be a groove or hole, in some examples.

Preferably, the panel further comprises a mounting feature the first surface or the second surface. In this way, parts of a vehicle can be fixed onto the panel more easily. The mounting feature can be an internal depression configured to interface with a part for a vehicle while ensuring the panel can be stacked efficiently in a build volume of a 3D printer.

Preferably, the panel comprises aluminium. In this way, the panel is formed from a strong and lightweight material that can be 3D printed easily. The panel can be formed from aluminium powder.

Preferably, there is provided a stack of any the additively manufactured described above, wherein the separation of individual panels in a build volume of a 3D printer is minimised in order to maximise use of the build volume. The separation can be minimised by selecting a suitable combination of panel thickness and curvature. If the panels comprise any protrusions, such as a flange for providing support to a part of a vehicle, the size, orientation, and position of the protrusions can be selected to minimise the separation of individual panels in the stack. The skilled person would appreciate that there is a multitude of ways these various parameters of a panel could be arranged to minimise separation of the panels and hence maximise use of the build volume.

In one specific example, each panel's thickness and curvature, together with each panel's protrusion size, orientation and positioning (if protrusions are present) can be selected to satisfy a relationship stack depth < panel depth + (3 x max panel thickness), where "stack depth" refers to the depth of two stacked panels along a stacking direction, "panel depth" refers to the depth of a single stacked panel in the stacking direction, and "max panel thickness" refers to the maximum thickness of the panel as measured between the exposed outer faces of the first and second surfaces. It is envisaged that panels meeting this criterion represent a useful compromise between complexity and stackability.

Preferably, the separation of individual panels in the build volume is lowest at the point of maximum panel thickness. The maximum panel thickness can limit how closely the panels can be stacked. Arranging the panels in the stack in this way ensures the panels are stacked as closely as possible.

Preferably, each panel has a profile that conforms to the profile of an adjacent panel, thereby allowing one panel to be nested within the other in order to minimise separation of panels in the build volume. In this way, the stack of panels can be produced efficiently in the 3D printer to increase manufacturing throughput.

According to a further aspect of the present invention, there is provided a vehicle body comprising an additively manufactured panel according to the first aspect of the invention.

The vehicle body can be composed in part, or, preferably, predominantly or entirely from additively manufactured panels of the first aspect of the invention. This allows vehicle bodies to be manufactured efficiently while also benefiting from the advantages associated with additive manufacturing. In contrast, conventional vehicle body structures may be composed of parts or shapes that are not possible to arrange in a build volume efficiently so that a high proportion of the build volume can be utilised in a single printing operation.

The vehicle body can be any kind of vehicle body that provides a frame, such as an endoskeleton or exoskeleton.

Preferably, all main load bearing sections of the vehicle body are formed from panels according to the first aspect of the invention. In this way, all of the main parts of the vehicle body can be efficiently manufactured by a 3D printer.

According to a second aspect of the present invention, there is provided a method of manufacturing a vehicle body, comprising: additively manufacturing, in a build volume of a 3D printer, a plurality of panels in a stacked configuration or arrangement, each panel comprising a first surface, a second surface, and a support structure positioned between the first surface and the second surface; removing the plurality of stacked panels from the 3D printer; and forming a part of at least one vehicle body using at least one of the plurality of stacked panels.

In this way, one or more vehicle bodies can be assembled more efficiently. Each panel may correspond to any of the embodiments of the first aspect of the invention described above.

The stack of panels can be assembled together to form a single vehicle body. In this case, each panel in the plurality of panels may not necessarily have the same shape, but nevertheless have a stackable contoured shape that enables high utilisation of the build volume. Alternatively, the plurality of panels can have the same shape. In this instance, each panel can be incorporated into a respective vehicle body. Thus, several vehicle bodies can be built over time using several panels from different printing operations. In either case, building a stack of panels allows high utilisation of the build volume of a 3D printer for greater manufacturing throughput.

According to a third aspect of the present invention there is provided a panel for a vehicle body, comprising: a first surface and a second surface; a support structure positioned between the first surface and the second surface; and an air channel to an enclosed space between the first surface and the second surface, wherein the air channel and the enclosed space provide an acoustic mechanism configured to absorb or generate sound.

In this way, the panel can integrate functions of an acoustic component, which is normally external to a vehicle body, into the vehicle body. This provides weight savings and reduces the overall cost and production time of the vehicle. The panel may be additively manufactured or manufactured by other means. The panel can have any of the features described above with respect to the first aspect of the invention.

According to a fourth aspect of the present invention there is provided a panel for a vehicle body, comprising: a first surface and a second surface; a support structure positioned between the first surface and the second surface; and a first fluid inlet, a first fluid outlet, and a first fluid channel fluidically connecting the first fluid inlet to the first fluid outlet.

During use in a vehicle body, a fluid to be cooled, such as oil, can be passed through the first fluid channel and heat can be exchanged with the panel. The panel is connected to the remainder of the vehicle body, which provides a heat sink that can absorb and dissipate heat from the fluid. In this way, the panel can integrate functions of a heat exchanger component normally external to a vehicle body within the vehicle body. This provides weight savings while reducing the overall cost and production time of the vehicle. The panel may be additively manufactured or manufactured by other means.

Incorporating a heat exchange system into a vehicle body enables the heat exchanger to positioned away from the engine. Stress caused by vibration from the engine can cause heat exchangers to rupture over time, ultimately leading to engine failure. Placing the heat exchanger further from the engine reduces the stress on the heat exchanger, thereby improving the robustness of the vehicle.

The panel can have any of the features described above with respect to the first aspect of the invention.

Preferably, the panel further comprises a second fluid inlet, a second fluid outlet, and a second fluid channel fluidically connecting the second fluid inlet to the second fluid outlet, the second fluid channel arranged to exchange heat with the first fluid channel. This enables a cooling fluid to be provided in the second fluid channel.

BRIEF DESCRIPTION OF DRAWINGS

Embodiments of the invention are now described, by way of example, with reference to the drawings, in which: Figure 1 shows a schematic perspective view of a panel according to an embodiment of the invention; Figure 2 shows a cross sectional schematic diagram of a central portion of a panel according to an embodiment of the invention; Figure 3 shows a perspective view of a stack of panels in a build volume of a 3D printer according to an embodiment of the invention; Figure 4 shows a side view of a stack of panels in a build volume of a 3D printer according to an embodiment of the invention; Figure 5 shows a cross sectional schematic diagram of a curved side portion of a panel according to an embodiment of the invention; Figure 6 shows a cross sectional schematic diagram of a curved side portion of a panel distinct from embodiments of the invention; Figure 7 shows a schematic perspective view of a vehicle body according to an embodiment of the invention; Figure 8 shows a schematic perspective view of a panel according to an embodiment of the invention; Figure 9 shows a schematic perspective view of a panel according to an embodiment of the invention; Figure 10 shows a schematic perspective view of a panel according to an embodiment of the invention; Figure 11 shows a schematic top view of a panel according to an embodiment of the invention; Figure 12 shows a flowchart of a method according to an embodiment of the invention; and Figure 13 shows a cross sectional schematic diagram of a stack of panels according to an embodiment of the invention.

DETAILED DESCRIPTION

Figure 1 shows a schematic perspective view of an additively manufactured panel according to an embodiment of the invention.

A panel 10 is provided and comprises a first surface 12, a second surface 14, and a support structure 16 arranged therebetween. The panel 10 comprises a substantially flat central portion 18 and two curved side portions 20 on opposing edges of the panel 10. The first surface 12, the second surface 14, and the support structure 16 form a continuous structure where the support structure provides mechanical strength to the panel 10 to enable use of the panel 10 in a vehicle body.

Figure 2 shows a cross sectional schematic diagram of the central portion 18, showing the support structure 16 in greater detail. The support structure 16 comprises a square grid of walls that extend perpendicularly between the first surface 12 and the second surface 14. The support structure 16 may also comprise walls parallel to the first surface 12 and the second surface 14 so that the support structure 16 comprises a plurality of cuboidal cells. In other embodiments, the support structure 16 can be any other kind of structure, such as a honeycomb structure, a lattice structure having struts or ribs in place of walls, or an irregular support structure comprising a mix of walls and struts or irregular shapes.

The support structure 16 can be configured in different ways in different parts of the panel 10 to accommodate different structural requirements. For example, in some areas the support structure 16 can be designed to provide stiffness, whereas in other areas it can be designed to provide energy absorption to manage impacts. The density of the support structure 16 can also be varied. In some areas it can be solid, e.g., where mountings are required. In other areas of the panel 10 the support structure 16 may comprise large cavities to reduce the mass of the panel 10 or to provide strategic points for controlled structural failure in case of impacts. Design of the support structure 16 can be performed using a computer-based optimisation, which may optimise various aspects of the support structure 10, such as its strength and density, based on an overall design of a vehicle or vehicle body.

The panel 10 comprises aluminium. In other embodiments, the panel 10 can comprise any 3D printable material that has sufficiently strong mechanical properties to form a vehicle body.

The panel 10 has a substantially trapezoidal shape (i.e., referring to the outline of the panel 10 as viewed from a plan perspective, ignoring the curvature of the panel 10). However, in other embodiments the panel 10 can have other shapes, such as a square, rectangular, triangular, or an irregular shape.

The central portion 18 of the panel 10 is substantially flat and forms a main plane of the panel 10, i.e., a plane to which most of the panel 10 is parallel. The curved side portions 20 of the panel 10 bend at obtuse angles relative to the central portion 18 (i.e., relative to the main plane of the panel 10). This allows the panel 10 to be used in contoured vehicle bodies. The curvature of the side portions 20 also allows the panel 10 to be joined to other panels, which have different shapes, to form a contoured vehicle body. In this example, the contoured shape of the panel 10 comprises obtuse angles that allows multiple copies of the panel 10 to be stacked within a build volume of a 3D printer, as illustrated in Figure 3 and discussed further below. In other embodiments, the panel 10 can have any other contoured shape to allow a plurality of similar panels to be stacked with respect to one another.

As shown in Figure 2, a separation distance (D) can be defined between the external sides of the first surface 12 and the second surface 14. In this embodiment, the separation distance D is approximately constant across the length and breadth of the panel 10. This improves the stackability of the panel 10.

In other embodiments, the separation distance may vary, for example if a particular part of a vehicle body requires one of the first or second surfaces 12, 14 to be thicker due to strength requirements.

The panel 10 can be produced using any suitable additive manufacturing (or "3D printing") process and equipment. The panel 10 can also comprise external features produced from machining after the additive manufacturing.

Figure 3 shows a schematic diagram of several copies of the panel 10 arranged in a build volume 22 of a 3D printer in a stacked configuration. Figure 4 shows a schematic diagram of the same stack of panels from a side perspective.

The build volume 22 is a volume defining the space that an additive manufacturing unit can deposit or solidify material to create components. The build volume 22 has a cube shape in this example, but in other examples the build volume 22 may have other shapes, such as a cuboidal shape.

As shown, the contoured shape of the panel 10 allows several identical copies of the panel 10 to fit repeatedly into the build volume 22. The curved portions 20 of each panel bend at obtuse angles with respect to the corresponding central portion 18, which avoids the curved portions 20 creating an obstruction for the adjacently stacked panels. This allows a larger number of panels to be produced per use of the 3D printer for greater manufacturing throughput. The panel 10 may be stackable within a distance of 1mm or less from other panels in the stack. This allows one panel to be nested within the shape of a neighbouring panel, thereby making the most efficient use of the build volume 22.

However, in other embodiments the panel can also have other contoured shapes with protruding portions while nevertheless maximising the use of the build volume 22. An example of this is depicted in Figure 13, which shows a schematic cross section of a stack 210 of additively manufactured panels comprising a panel 212 and a panel 214.

The panel 212 is similar to the panel 10 and comprises a first surface 12, a second surface 14, and a support structure 16 arranged therebetween, as described previously. As shown, the panel 212 is curved and has a thicker central portion 213a compared to its edge portions 213b, which can be useful for providing extra structural support to a vehicle body. The panel 212 comprises flanges 216 for providing support to a part of a vehicle. The flanges 216 are provided at the edge portions 213b and oriented outwards towards the edges of the panel 212. The panel 214 is identical to the panel 212. The flanges 216 on each panel are positioned and oriented outwards to allow the panel 212 to nest with the panel 214, as depicted. This allows the panels 212, 214 to provide additional functions in a vehicle body while also making more efficient use of the build volume 22.

The stack 210 is arranged so that the panel 212 and the panel 214 are positioned as close as possible to minimise the separation distance between the panel 212 and the panel 214, so that the build volume 22 usage can be maximised.

A reference arrow in Figure 13 indicates the maximum panel thickness 218 as measured between the first surface 12 and the second surface 14. A panel depth 220 can be defined as the longest extent of a panel in the stacking direction. A stacking depth 222 can be defined as the total extent of two panels in the stacking direction. These distances are also indicated by reference lines. It is desirable to minimise the stacking depth 222 to maximise use of the build volume 22. The orientation of the flanges 216 and the degree of curvature of the panels 212, 214 are selected to minimise the stacking depth 222 while providing the necessary structural properties for a vehicle body. In general, the thickest part of a panel can cap the extent to which the stacking depth 222 can be minimised. Therefore, the thickest parts 213a of the panels 212, 214 are arranged as close as possible in the stack 210 so that the distance between the panel 212 and the panel 214 is lowest at the thicker central portions 213a. This is one way of minimising the stacking depth 222.

The features (i.e., curvature, thickness, protrusion size, orientation and position) of the panel 212 and the panel 214 can be chosen to satisfy the relationship: stacking depth < panel depth + (3 x maximum panel thickness). In practical scenarios, it is envisaged this constraint provides a panel that is efficiently printable while allowing for protrusions or irregular features that provide structural functions in a vehicle body.

The stack 210 comprises two panels in the illustrated example, however it would be apparent to the skilled person that the stack may comprise several more panels in practice.

In other embodiments, the stack 210 can include panels having other types of protrusions as well as other thickness profiles.

Returning to the panel 10, Figure 5 shows a schematic cross-sectional view of a curved side portion 20 of the panel 10, showing how the side portion 20 bends at an obtuse angle (0) to the central portion 18. As shown in Figure 5, reference line 18a is parallel to the central portion 18. Reference line 20b is parallel to the part of the first surface 12 and the second surface 14 at the periphery of the panel 10, where the side portion 20 ceases to curve further. The contoured shape of the panel 10 is such that the angle (0) between the reference lines 18a and 20a is obtuse.

Figure 6 shows a panel 21 not according to the present invention that has curvature 21b that bends at an acute angle (A) relative to a substantially flat portion 21a of the panel 21. As shown by the reference arrow, this type of curvature creates an overhanging region 21c that prevents efficient stacking of the panel 21 in a build volume of a 3D printer. In contrast, the curvature as shown in Figure 5 would not create an obstruction for efficient stacking.

In other embodiments, the panel 10 can have other more complex shapes utilising obtuse angles to enable efficient stacking of the panel in a build volume. In one example, a peripheral region of the panel 10 can be substantially flat to form a main plane of the panel 10, and a central region can have a depression forming a bowl shape.

Figure 7 shows a schematic perspective view of a vehicle body 24 for a car comprising the panel 10 and additional panels according to embodiments of the invention.

The vehicle body 24 comprises a front end 26 comprising the panel 10, a panel 32 and a panel 34, which have alternative shapes compared to the panel 10 for forming different parts of the vehicle body 24. The panel 32 and the panel 34 have a similar structure to the panel 10. Namely, each comprises first and second surfaces joined by a support structure. Each of the panel 32 and the panel 34 have contoured shapes comprising obtuse angles that allows each of the panel 32 and the panel 34 to be efficiently printed in a stacked configuration in a build volume of a 3D printer. This allows the front end 26 to be manufactured efficiently using a 3D printer. As shown in Figure 7, the front end 26 comprises further panels that are similar to the panel 32 and the panel 34.

In this example embodiment, the front end 26 is attached to a tub 28, which forms a rear end of the vehicle body 24. The tub 28 may be formed by conventional manufacturing means, such as by casting. The vehicle body 24 is an endoskeleton for a car that supports additional vehicle components, such as a bumper structure 36 and wheels 38 as shown in Figure 7.

In other embodiments, the whole vehicle body 24, or at least all main load bearing sections, can be formed from panels similar to the panel 10, instead of only the front end 26. The vehicle body 24 can also have an exoskeleton shape in other embodiments. The vehicle body 24 can also be formed from the panel 212 as shown in Figure 13.

Figure 8 shows a cross section of a panel 40 according to an alternative embodiment of the invention. In this example, the panel 40 is additively manufactured in the manner described previously.

The panel 40 comprises a first surface 42, a second surface 44, and a support structure 46 arranged between and joining the first and second surfaces 42, 44. The first surface 42, the second surface 44 and the support structure 46 perform the same functions as the corresponding features of the panel 10. The support structure 46 comprises walls arranged in a hexagonal grid that extend perpendicularly between the first surface 42 and the second surface 44 (i.e., a honeycomb structure), as shown in Figure 8. Other types of support structures would also be suitable, as shown in Figure 9 and discussed further below. In Figure 8, the first surface 42 is partially removed for the purposes of illustration.

The panel 40 differs from the panel 10 in that the first surface 42 comprises a plurality of apertures 48. The apertures 48 provide an air channel to otherwise enclosed spaces 49 formed within the support structure 46. Due to the hexagonally arranged walls of the support structure 46, each enclosed space 49 has the shape of a hexagonal chamber.

The apertures 48 and the spaces 49 are configured to act as a plurality of Helmholtz resonators. Helmholtz resonators can, in general, be configured to perform various acoustic functions. For example, the Helmholtz resonators can be configured to trap particular frequencies to provide a sound dampening effect, which can reduce or modulate engine noise. The particular frequencies affected can vary depending on the volume and shape of the enclosed spaces 49 as well as the position and size of the apertures 48. The apertures 48 and the spaces 49 can be configured to perform any kind of acoustic function in a vehicle. Providing acoustic functions in the vehicle body is more efficient in terms of the weight and build time of the vehicle, due to the avoidance of making and installing a separate component.

The panel 40 is preferably additively manufactured, which provides greater flexibility in the types of cavities that can be produced within the support structure 46, enabling a wider range of acoustic effects to be implemented.

In this example, the apertures 48 are provided in a regular grid on the first surface 42 with a high spatial frequency so that each enclosed space 49 has several apertures providing an air channel. However, in other embodiments the apertures 48 can be provided in clustered arrangement, or only one aperture may be provided per enclosed space 49.

Figure 9 shows a cross section of a panel 50 according to an alternative embodiment of the invention.

The panel 50 comprises a first surface 52, a second surface 44, and a support structure 56 arranged therebetween. The first surface 52, the second surface 54 and the support structure 56 perform the same functions as the corresponding features of the panel 10. The support structure 56 comprises walls arranged in a square grid that extend perpendicularly between the first surface 52 and the second surface 54, as shown in Figure 9. Other types of support structures would also be suitable. In Figure 9, the first surface 52 is partially removed for the purposes of illustration.

The panel 50 differs from the panel 10 in that the first surface 50 comprises a plurality of apertures 58. The apertures 58 provide an air channel to otherwise enclosed spaces 59 formed within the support structure 56. Due to the square grid of walls that form the support structure 46, each enclosed space 59 has the shape of a cuboidal chamber. The panel 50 differs from the panel 40 in that at least one wall that forms each enclosed space 59 comprises a flexible membrane 57.

The flexible membrane 57 can be a particularly thin wall structure of the same or different material that is capable of vibrating to generate or amplify sound. The apertures 58 and the spaces 59 may have a specific shape, volume and relative position that is configured to generate or amplify a specific frequency of sound. This can be used to amplify an engine sound, in one example.

The panel 50 is preferably additively manufactured, which provides greater flexibility in the types of cavities that can be produced within the support structure 56, enabling a wider range of acoustic effects to be implemented.

In this example, the apertures 58 are arranged in clusters of rows provided at spaced positions on the first surface 42. In other embodiments, the apertures 58 can be positioned in any other suitable way to provide a desired acoustic effect.

Figure 10 shows a cross section of a panel 60 according to an alternative embodiment of the invention. Figure 11 shows a schematic illustration of a plan view of the panel 60. In this example, the panel 60 is additively manufactured in the manner described previously.

The panel 60 comprises a first surface 62, a second surface 64, and a support structure 66 arranged therebetween and joining the first and second surfaces 62, 64. The first surface 62, the second surface 64 and the support structure 66 perform the same functions as the corresponding features of the panel 10. The support structure 66 comprises walls arranged in a square grid that extend perpendicularly between the first surface 62 and the second surface 64, as shown in Figure 10. Other types of support structures would also be suitable, as discussed previously.

The panel 60 is configured to operate as a heat exchanger. To this end, the panel 60 comprises a first fluid inlet 68, a first fluid outlet 70, and a first fluid channel 71 fluidically connecting the first fluid inlet 68 to the first fluid outlet 70. The panel 60 also comprises a second fluid inlet 72, a second fluid outlet 74, and a second fluid channel 76 fluidically connecting the second fluid inlet 72 to the second fluid outlet 74. Various arrows in Figures 10 and 11 indicate fluid flow directions according to an example implementation.

The first fluid channel 71 and the second fluid channel 75 are each formed by respective channels in the support structure 66. Each of the first and second fluid channels 71, 75 comprise an internal porous support structure to increase the mechanical strength of the panel 60. Using an internal porous support structure also increases the surface area of the panel 60 in contact with the fluid flowing through the respective fluid channel. This increases the extent to which the fluid can exchange heat with the vehicle body, which can act as a heat sink. For this reason, in other embodiments the panel 60 can also operate as a heat exchanger having only a single fluid channel, where the vehicle body is used to cool a fluid in the single fluid channel.

The first fluid channel 71 and the second fluid channel 75 are provided adjacent one another to enable fluids flowing through each channel to exchange heat, as shown in Figure 11 schematically by dashed lines. The first fluid channel 71 and the second fluid channel 75 are shown as arranged side by side. However, any other suitable arrangement can be implemented, such as a gyroid configuration. For instance, each fluid channel can be provided as a substantially flat cavity spread across the extent of the panel 60 in different layers of the panel 60. In the plan view of Figure 11, channels of this shape and arrangement would appear to be overlapping. A single layer of the support structure 66 may separate the fluid channels in this case. Such an arrangement would increase the surface area of the support structure 66 shared by each channel to promote the exchange of heat between the fluids therein.

In one example usage, a hot fluid to be cooled, such as engine oil, can be pumped through the first fluid channel 71. A cooling fluid, such as water, can be pumped through the second fluid channel 75 to cool the oil in the first fluid channel 71. Suitable conduits can be attached to each of the first and second fluid inlets 68, 72 and the first and second fluid outlets 70, 74.

The panel 60 can be incorporated into a vehicle body, such as the vehicle body 24 of Figure 7, to provide a heat exchanger integrated into the frame of the vehicle. This can be advantageous where the panel 60 is used in place of a heat exchanger mounted on the engine, which can be prone to failure due to vibrational loads caused by operation of the engine creating leaks in the heat exchanger.

The panel 60 is preferably additively manufactured, which provides greater flexibility in the types and shapes of fluid channels that can be produced within the support structure 66, enabling greater control over the functioning of the heat exchanger.

Each of the panel 40, the panel 50, and the panel 60 may comprise contoured shapes using obtuse angles for efficient stacking in a build volume, as described previously. For instance, each may comprise curved side portions that bend at obtuse angles to a flat central portion in the same manner as described with respect to the panel 10.

Figure 12 shows a flowchart of a method 100 of manufacturing one or more vehicle bodies according to an embodiment of the invention.

The method 100 can be used to manufacture a single vehicle body from panels as described previously in as few printing operations as possible. Alternatively, the method 100 can be used to manufacture several vehicle bodies, each of which may have an identical shape, in as few printing operations as possible.

At step 102, a stack of panels is manufactured in any suitable type of 3D printer in a single build volume. The stack can comprise identical copies of any of the panel 10, the panel 212, the panel 40, the panel 50, or the panel 60. In this case, each panel in the stack may be intended for incorporation into a respective vehicle body of a plurality of identical vehicle bodies. For instance, the stack of panels may comprise 10 identical panels, each intended to form the same part of one of 10 identical vehicle bodies.

Alternatively, the stack can comprise panels having different shapes for forming different parts of a single vehicle body.

In either case, the 3D printer prints a plurality of panels in a stacked arrangement.

Each panel in the stack has a contoured shape that enables the panels to fit closely together in the build volume. The panels in the stack can utilise curvature having obtuse angles, as described previously in relation to the panel 10, to enable the panels to be stacked. The panels in the stack can equally be formed and arranged as described with respect to Figure 13 to maximise the use of the build volume. Manufacturing panels in this way allows the build volume of the printer to be occupied to the greatest extent possible, as illustrated in Figures 3 and 4, in each printing operation. This reduces the number of 3D printing operations required to produce the necessary number of panels.

In step 104, the stack of panels is removed from the 3D printer. Optionally, each panel may be subjected to further manufacturing steps after being 3D printed.

In step 106, the stack of panels can be assembled into one or more vehicle bodies. For example, each panel can be joined to other similar panels using welding or bolting. Any suitable method of connecting the panels can be implemented. Each panel in the stack may comprise one or more bonding features, such as interlocking grooves or holes, configured to facilitate attachment of the panels.

In step 108, steps 102 to 106 can be repeated until one or more vehicle bodies, or sections of vehicle bodies (such as the front end 26 of Figure 7), are assembled from various panels. In the case where only sections of vehicle bodies are produced in steps 102 to 108, the one or more sections can be joined to other vehicle body sections to form a complete vehicle body.

The skilled person would appreciate that step 106 of assembling the panels can also be performed after the additive manufacturing of all of the required panels is completed. In practice, printing and assembly of the panels may be undertaken in parallel.

Claims

CLAIMSAn additively manufactured panel for forming a vehicle body, comprising: a first surface and a second surface; and a support structure positioned between the first surface and the second surface; wherein the first surface and the second surface have a contoured shape that enables a plurality of like panels to be stacked together.
2. A stack of the additively manufactured panels of claim 1, wherein the separation of individual panels in a build volume of a 3D printer is minimised in order to maximise use of the build volume.
3. The stack of additively manufactured panels of claim 2, wherein the separation of individual panels in the build volume is lowest at the point of maximum panel thickness.
4. The stack of additively manufactured panels of claim 2 or claim 3, wherein each panel has a profile that conforms to the profile of an adjacent panel, thereby allowing one panel to be nested within the other in order to minimise separation of panels in the build volume.
5. The panel of claim 1, wherein the contoured shape comprises obtuse angles.
6. The panel of claim 5, wherein the contoured shape comprises a substantially flat central portion and one or more curved edge portions that form a bend at an obtuse angle to the substantially flat central portion.
7. The panel of any of claims 1, 5 or 6, further comprising an air channel to an enclosed space between the first surface and the second surface, wherein the air channel and the enclosed space provide an acoustic mechanism configured to absorb or generate sound.
8. The panel of claim 7, wherein the air channel comprises one or more apertures on the first surface, and wherein the air channel and the support structure are configured to provide a Helmholtz resonator.
9. The panel of claim 7 or claim 8, wherein the acoustic mechanism comprises a flexible membrane configured to generate sound.
10. The panel of any of claim 1 or claims 5 to 9, further comprising a first fluid inlet, a first fluid outlet, and a first fluid channel fluidically connecting the first fluid inlet to the first fluid outlet.
11. The panel of claim 10, further comprising a second fluid inlet, a second fluid outlet, and a second fluid channel fluidically connecting the second fluid inlet to the second fluid outlet, the second fluid channel arranged to exchange heat with the first fluid channel.
12. The panel of any of claim 1 or claims 5 to 11, wherein the first surface and/or the second surface have a maximum thickness of 4 mm or less, preferably 2mm or less, more preferably 1 mm or less.
13. The panel of any of claim 1 or claims 6 to 12, wherein a separation distance between the first surface and the second surface is substantially constant across the panel.
14. The panel of claim 1 or claims 6 to 13, further comprising a mounting feature on the first surface or the second surface.
15. The panel of claim 1 or claims 6 to 14, wherein the panel comprises aluminium.
16. A vehicle body comprising an additively manufactured panel according to claim 1 or any of claims 5 to 15.
17. The vehicle body of claim 16, wherein all main load bearing sections of the vehicle body are formed from panels according to any of claim 1 or claims 5 to 15.
18. A method of manufacturing a vehicle body, comprising: additively manufacturing, in a build volume of a 3D printer, a plurality of panels in a stacked configuration, each panel comprising a first surface, a second surface, and a support structure positioned between the first surface and the second surface; removing the plurality of stacked panels from the 3D printer; and forming a part of at least one vehicle body using at least one of the plurality of panels.