TECHNICAL FIELD

The present disclosure relates to apparatus and methods for marking, or depositing a material on, a ground surface. In particular, but not exclusively, it relates to an autonomous ground deposition machine having a novel paint, or deposition material, quick remove/replace cartridge design and quick connect mounting for said cartridge. Further aspects of the invention relate to a method of replacing said cartridges.

BACKGROUND

Ground marking has traditionally been carried out using manual processes. Ground marking may be carried out using manual line marking equipment, for example to mark out sports pitches, or by using a manual image painting process using stencils and paint which may be painted or sprayed into the cutouts in the stencils, for example to mark areas of ground with a sponsor logo. Such logos may be required to be large enough to see from a long distance, in some cases by aerial photography of all or parts of a sports pitch or venue, and such manual marking can therefore take considerable time to complete, especially if the image to be painted is complex or is a multi-colour image. Further, such a manual process can be a complex task requiring significant user skill to complete. In addition, manual painting of a ground surface can often only provide satisfactory visible results when the ground surface is saturated in paint, such that the intensity of an image is consistent at different parts of the image. Such saturation of the ground surface with paint firstly consumes considerable paint at considerable cost, secondly causes difficulty in removing the paint once the image is no longer required to be present on the ground surface, and thirdly has a more detrimental effect on the environment.

Autonomous ground printers, also known as autonomous ground marking machines, are becoming more commonplace for line marking of sports pitches and for image printing of logos. Such ground printers can autonomously move on a predetermined path and deposit paint in a predetermined pattern to mark lines or print pixels on a ground surface. In particular, paint or ink can be deposited by a single print nozzle to form a line or a pixel of an image, or from multiple print nozzles to form multiple pixels of an image. However, such printing can still be slow when an image requires multiple colours of paint or ink to be deposited, and the image intensity can vary dependent on the ground surface.

One approach to automating ground marking is found in US 2005/0055142 Al in which a turf image marker comprises a ground maintenance vehicle adapted to both mow and store grass as well as carry a marking device that includes a delivery system for applying a marking material to the ground. Dispensing devices for putting down marking materials are provided in the form of boxes requiring mechanisms that require to be driven such as a motor, electric, air or other fluid motor.

Movement or sloshing of the contents of a box can cause the drive and/or balance of a turf image marker to be affected, an affect which becomes more pronounced the more the weight of the ground marking material is compared to the turf image marker carrying the ground marking material. US 2005/0055142 may be able to cope with a certain amount of imbalance due to the size and weight of the agricultural machine being used and the coarse resolution of any image being deposited.

One approach to scalable autonomous ground marking is found in the Applicant's co pending patent "Ground Printing Machine", Micropply Limited, PCT/GB2021/052671, which discloses an ADDR machine capable of ground printing.

However, in order to make ground marking or depositing materials on the ground as efficient as printing or marking on paper a novel approach is needed in order to seek high resolution of marking combined with development of the machine carrying the marking material towards a reduction in size, weight and increase in portability.

SUMMARY OF THE INVENTION Aspects and embodiments of the invention provide a ground printer for marking a ground surface and a method of marking a ground surface, as claimed in the appended claims.

According to a first aspect of the present invention, there is provided an autonomous deposition machine for depositing a material on a ground surface, the autonomous deposition machine comprising: locomotion means, the locomotion means mounted on a chassis; a deposition arrangement comprising one or more spray nozzles; a deposition material cartridge mount, wherein the deposition material cartridge mount is operable to receive a removable paint cartridge at a first end and is fluidly coupled to the deposition arrangement at a second end.

Advantageously, the combination of a retaining holders for retaining deposition material tanks in situ in a frame, or chassis, along with the hose connection mechanism itself, reduces weight and leads to a more compact design. Thus, this means there is no need for a tank frame within the chassis frame itself, reducing weight and again leading to a compaction of design. More user friendly, easier to see paint usage amounts.

Preferably, wherein the deposition material cartridge mount may also comprise a quickconnect connector and/or wherein the deposition material cartridge mount further comprises a screw and/or thread arrangement. This provides the advantage of being able to replace deposition material cartridges quickly and easily.

Further preferably wherein the deposition material cartridge mount may further comprise a flexible guide, wherein the flexible guide is operable to guide a deposition material cartridge into the quick-connect connector. Wherein the flexible guide further comprises a retaining means located at an end furthest away from the chassis mount, wherein the retaining means is operable to retain a deposition material cartridge in place. Advantageously making it easier to insert a deposition material cartridge and keep it securely in place until it needs to be replaced.

Also preferably, wherein each spray nozzle of the one or more spray nozzles may be coupled to a separate respective deposition material cartridge mount, and/or wherein each spray nozzle of the one or more spray nozzles is fluidly coupled to a separate respective deposition material cartridge mount via a spray assembly. Preferably, wherein the spray assembly is mounted inside the chassis of the autonomous deposition machine. Preferably wherein the deposition material cartridge mount is mounted on the chassis frame. Further preferably, wherein the deposition material cartridge mount is mounted externally on the chassis casing.

Further preferably, wherein the spray assembly further comprises a pump and a valve and/or is coupled to the separate respective deposition material cartridge mount via flexible tubing to accommodate movement of the spray nozzles relative to the respective deposition material cartridge mount.

Preferably wherein, the ground printer may further comprise a controller configured to control the position of the ground printer on a ground surface, to control the position of the plurality of spray nozzles on the ground printer, and to control the operation of the plurality of spray nozzles to mark the ground surface. Wherein the controller may be configured to control a valve for each of the plurality of spray nozzles dependent upon the position of the ground printer on the ground surface.

According to a second aspect of the present invention, there is provided a removable paint cartridge suitable for use with the autonomous deposition machine according to the first aspect.

According to a third aspect of the present invention, there is provided a method of controlling an autonomous deposition machine of the first aspect, the method comprising: connecting a paint cartridge to a deposition material cartridge mount located on the autonomous deposition machine; receiving deposition instructions; processing said deposition instructions; and controlling a plurality of valves, each valve being connected between a respective paint cartridge and a respective spray nozzle, to deposit paint on the ground surface below the respective spray nozzle in accordance with the deposition instructions.

The method may further comprise controlling a plurality of valves, each valve being connected between a respective paint cartridge and a respective spray nozzle, to deposit paint on the ground surface below the respective spray nozzle. The method may comprise: moving the plurality of spray nozzles on the ground printer in the third direction, substantially orthogonal to the first direction and substantially orthogonal to the second direction.

The method may also further comprise for each of the paint cartridges, monitoring a parameter relating to a volume of paint in the respective paint cartridge; and stopping the ground printer when one of the parameters relating to the volume of paint in the paint cartridges reduces below a predetermined level.

Preferably, wherein the user sends deposition instructions to the autonomous ground marking machine via a cloud server or device, or an edge server or device.

Also, wherein the material to be deposited may be marking material, paint or ink, and the deposition instructions are printing instructions.

Within the scope of this application, it is expressly intended that the various aspects, embodiments, examples and alternatives set out in the preceding paragraphs, in the claims and/or in the following description and drawings, and in particular the individual features thereof, may be taken independently or in any combination. That is, all embodiments and/or features of any embodiment can be combined in any way and/or combination, unless such features are incompatible. The applicant reserves the right to change any originally filed claim or file any new claim accordingly, including the right to amend any originally filed claim to depend from and/or incorporate any feature of any other claim although not originally claimed in that manner.

BRIEF DESCRIPTION OF THE DRAWINGS

One or more embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which:

Figure 1 is a side view of a ground printer with an externally mounted removable paint cartridge, according to an embodiment of the invention;

Figure 2 is a perspective view of a quick-connect cartridge mount used to couple the ground printer of Figure 1 with an externally mounted removable paint cartridge; and

Figure 3 illustrates a side view of an externally mounted removable paint cartridge and associated spray arrangement for the ground printer of Figure 1.

In the drawings, like parts are denoted by like reference numerals.

Examples of the present disclosure relate to an apparatus for marking a ground surface. In particular, examples of the present disclosure relate to an apparatus for marking a ground surface having spray nozzles for ejecting paint or ink, under pressure, onto a ground surface. Non-limiting examples will now be described with reference to the accompanying drawings.

The figures illustrate an apparatus for marking a ground surface, in the form of an autonomous ground marking machine 10. The autonomous ground marking machine 10 is intended for printing line markings and/or complex images on a ground surface without user intervention following an initial setup of the autonomous ground marking machine 10.

DETAILED DESCRIPTION Figure 1 is a side elevation of a ground marking autonomous ground marking machine 10, according to one embodiment of the present invention. The autonomous ground marking machine 10 further comprises a case or cover 12 held securely by a chassis (not shown) supporting a ground wheel arrangement 50 (1-4) and a print head arrangement 28.

The ground wheel arrangement 50 comprises wheels 50-1, 50-2, 50-3 and 50-4 to steer the autonomous ground marking machine 10 along a path to effect the printing, and this may be under the control of a print file that can be loaded into an on-board control system such as may be contained in a communications and navigation module 24. It should be clear to someone skilled in the art that only wheels 501 and 50-2 can be shown in Figure 1, as the second set of wheels 50-3 and 50-4 are on the rear side of the autonomous ground marking machine 10.

The print head arrangement 28 can be height adjustable, whereby to print finer or coarser images or to adapt to ground irregularities. The print head arrangement 28 can use any of a variety of printing techniques, including standard ink jet, spray, and 3D printing techniques involving melting plastic and dropping or shooting it at a ground surface.

As illustrated in Figure 1, the paint, or material to be deposited is retained onboard the autonomous ground marking machine 10 in a series of removable cartridges 30 (a, b, c), which are inserted into quick-connect cartridge mounts 35 (a, b, c) mounted on a mounting plate 40, located externally to the casing 12 of the autonomous ground marking machine 10.

Each spray nozzle 26 (1-6) of a plurality of spray nozzles 26 may be coupled to a separate respective paint cartridge 30 (a, b, c), as will be described in relation to Figure 3. The paint, or deposition material, may be ejected from each spray nozzle 26 under pressure to form small droplets of paint to uniformly cover the ground surface. Only three removable paint cartridges 30 (a, b, c) are shown for ease, as many removable paint cartridges 30 (a, b, c) as they are spray nozzles 26 (1-6) can be mounted via the quick-connect cartridge mounts 35 (described with further detail in Figure 2) on the mounting plate 40. As such in this embodiment, as there are six spray nozzles 26 (1-6), so there would need to be six paint cartridges 30 (a-f).

Each of the removable paint cartridges 30 (a, b, c) forms part of a pressurised airless spray system 20 (see Figure 3) and is connected to a respective spray nozzle arrangement 28 via an airtight valve outlet of the removal paint cartridge 30 (see Figure 3 for more details).

The autonomous ground marking machine 10 also comprises wheels 50-1 & 50-2 for movement, as well as a navigation and communication means 24, such as a beacon, GPS or other suitable sensor arrangement, as well as a start stop/control panel 23. The navigation and communication means 24 may be used for navigation or the autonomous ground marking machine 10 may use triangulation with known positioning reflectors and the laser for positioning. In operation, the autonomous ground marking machine 10 may be in constant communication with a positioning device and may reposition itself based on communication from a Global Positioning Device.

Figure 2 is a perspective diagram of a quick-connect cartridge mount used to couple the ground printer of Figure 1 with an externally mounted removable paint cartridge 30 of the present invention. There is shown a quick connect connector 31 formed of a male and female portion (31a & 31b), wherein the female portion 31a includes a flexible diaphragm 34b and the male portion 31b further includes a breather 34a, which when coupled, forms an airtight connection.

A paint cartridge 30 is guided into place by a connector guide 32, which is mounted on the chassis mount 40 and can be made of plastic or other suitable materials and which is flexible. At an end furthest away from the chassis mount 40, the connector guide 32 may further comprise at least one first cartridge retainer portion 33a which may interlock with a second cartridge retainer portion 33b located on the neck of removable cartridge 30. The first cartridge retainer portion 33a second cartridge retainer portions 33b providing extra stability and security when the paint cartridge is in position on the quick-connect cartridge mount 35.

The quick-connect cartridge mount 35 is mounted on the chassis mount 40, which is formed over or connected to the chassis 12 of the autonomous deposition machine 10.

Quick-connect connectors (31) are known in the art and are generally a male (31b) and female (31a) push fit cartridge mount coupling and can be released without the need for tools. Generally, they are comprised of a plunger on a spring mechanism, and in most paint deposition situations both parts would need to be able to be airtight/fluidly sealed when fitted. They usually comprise a tab or pressure release button or area in operation and in a preferred embodiment, both ends would have a dust cover, or be closed off, when not connected. Especially with the part located on the cartridge 30, as it would need to be turned upside down to insert it, as it would be very important that minimal material can escape when doing so. The advantage of having a protective cover on the receiving part of the quick cartridge mount 35 (a, b, c) mounted on the mounting place 40, is that it may be essential no dust or materials can get into the airless spray system (of Figure 3) when no cartridge 30 is fitted.

As such it should be clear to someone skilled in the art, that the opening area or 'neck' of the cartridge 30, must be compatible in design with the opening area or 'seat' area of the relevant quick-connect cartridge mount 35 (a, b, c). It should also be clear to someone skilled in the art that other connector arrangements, or combination of arrangements, may be suitable, including screw systems, or clip systems. Depending upon the materials to be deposited and the width of the hosing etc, different quick-connect connector solutions can be chosen.

In Figure 3, there is shown an airless spray nozzle arrangement 20 is shown, which is operable to convey paint from the paint cartridge 30 to a respective spray nozzle 26. As described previously in Figure 1, each paint cartridge 30 is externally mounted to the casing 12 of the autonomous ground marking machine 10 by means of a quick-connect cartridge mount 35 mounted on a mounting plate 40.

A valve 27, such as a solenoid valve, is located between the paint cartridge 30 and the spray nozzle 26. The valve T1 is controlled by an onboard controller (not shown), to be open when printing on the ground surface is required and closed when printing is not required. Each spray nozzle 26 may be coupled to the separate respective paint cartridge 30 via the flexible tubing 104 to accommodate movement of the spray nozzles 26 relative to the respective paint cartridges 30.

Also shown are two filters 22a, 22b, which may be used to filter the relevant deposition material(s) to ensure particulates don't block the flexible tubing 104 and spray nozzles 26, if required in certain deposition situations and with certain materials.

The plurality of spray nozzles 26 is mounted to a lower portion of a print head 28, which may be, in some embodiments, formed from a length of extruded rail with a plate through which the spray nozzles 26 project. The spray nozzles 26 are configured to spray paint onto the ground surface such that a desired marking, or a desired image, is printed onto the ground surface as the autonomous ground marking machine 10 follows instructions to carry out a printing task which may be received from a user of the autonomous ground marking machine 10.

A pump 29, such as a self-priming diaphragm pump 29, may be used to pressurise the airless spray system 20 for each respective spray nozzle 26. The pump 29 may be individually controlled by a controller (not shown) and the pressure for each pump 29 may be adjusted depending on the paint being used for the respective spray nozzle 26. Different paints may be of different viscosities, therefore requiring different pressure to be applied to the spray system for each spray nozzle 26. In operation, paint is ejected from the spray nozzles 26 under pressure, which may be up to a maximum of 10 bar (1000 kPa) hydraulic pressure per spray nozzle 26. In some embodiments the paint is ejected from the spray nozzles 26 at a pressure of 7 bar (700 kPa).

The spray system 20 may beneficially reduce or prevent dripping of paint from the spray nozzles 26, by providing back pressure at the spray nozzles 26. Such an arrangement differs from agricultural spray systems, which use less viscous fluids than the present invention and use breather nozzles to help with back pressure, which can lead to dripping of fluids onto the ground surface. However, in agricultural spray systems, dripping of the fluids onto the ground surface is generally not a problem. The higher viscosity fluids, such as paint, used in the present invention don't provide the same back pressure problem, and this coupled with the pressurization of the spray system minimises any dripping of paint onto the ground surface.

In some embodiments the flexible tubing 104 used to transfer or convey paint from a cartridge 30 to a spray nozzle 26 may have a small inner diameter, for example 2.5 mm diameter, with a relatively thin sidewall. Various materials may be used to form the flexible tubing 104 where some materials may be one of polyurethane, polyvinyl chloride, polypropylene, fluoropolymer, rubber, silicone or other similar materials.

The controller (not shown) may be configured to control a valve T1 , such as a solenoid valve, for each of the plurality of spray nozzles 26, dependent upon the position of the autonomous ground marking machine 10 on the ground surface.

Also shown is an ID tag 14 and an ID reader 13. ID tag 14 may also comprise a barcode or other smart label, which is used for identification of the cartridges 30. The ID reader 13 is an integral part of the chassis casing 12 and is for registering the presence of the cartridges 30 when firmly in place in the frame (not shown). The ID reader 13 may be a photodiode or a RFID tag that communicates with an ID tag 14 of the cartridge 30. ID tag 14 may also comprise a barcode or other smart label, which is used for identification of each cartridge 30. The autonomous ground marking machine 10 can communicate with a remote server (not illustrated), through any wired or wireless network, via the navigation/communications module 24. For example, the autonomous ground marking machine 10 may communicate with a remote server via a cellular network. A user can initiate the printing of a print task, such as the printing of markings or printing of an image, by selecting a printing task on a connected user device which then provides instructions for the printer to follow in order to carry out the printing task.

The user may also register the marking material using the ID tag 14 to match marking materials held in a database by way of communication with the navigation and communication means 24.

The database may contain a list of verified marking materials authorised for use and may in return grant permission for the autonomous ground marking machine 10 10 to accept the material and may, depending in the type of material, make mechanical or software adjustments. For example, a print head 28 height may be adjusted to spray fertilizer in a different way to the height needed for high resolution image printing.

The ID reader 13 may also be used to register the presence of the cartridges 30 and further verify that the correct cartridge 30 is located in the correct frame and may further undertake a verified check of the authenticity of the cartridge 30 using RFID technology or other suitable sensor technologies. The database may comprise a revocation list of packaging or materials that are no longer supported, out of date or out of contract. In which case an error message may be displayed to the user.

Although embodiments of the present invention have been described in the preceding paragraphs with reference to various examples, it should be appreciated that modifications to the examples given can be made without departing from the scope of the invention as claimed. The autonomous ground marking machine 10 and methods described herein can be adapted for use with different types of ground surface. For example, these could be, grass, turf, AstroTurf, artificial turf, synthetic turf, plastic turf, concrete, polished concrete, tarmac or tarmacadam ground surfaces, dirt, gravel, wood chip, carpeting, rubber, roads, asphalt, brick, sand, beaches, mud, clay wood, decking, tiling, stone, rock and rock formations of varying types of rock or stone, snow, ice, ice rinks, artificial snow, polymer surfaces such as polyurethane, plastic, glass and leather.

The autonomous ground marking machine and methods described herein can be adapted for use with different surfaces, such as sports (e.g. football, cricket, racing, rugby, hockey, ice hockey, skiing, shooting) pitches, ski slopes, dry ski slopes, race courses, gymnasiums, indoor sports venues and running tracks.

In some embodiments, the autonomous ground marking machine 10 and methods described herein may be used for printing or painting on a substrate or on the ground surface. This can be to print or paint, with inks or paint, logos, information, advertising or messages on the ground surface. When large images are printed, they are printed with adjacent dots or pixels so that when viewed from above or a suitable distance from afar (e.g. from the stand in a stadium or from a television view) the images are easily determined. Print instructions can be determined so that when an image, e.g. a logo is printed, they can be visible from stadium stand or by a viewer watching an event at home on television. The autonomous ground marking machine 10 and methods described herein offer an improvement to printing methods for advertising purposes. Brand logos, slogans, pictures etc. can be printed to advertise a brand, logo or message. These can be printed more efficiently, quickly and with a higher degree of accuracy than the methods and printers of the prior art.

The autonomous ground marking machine is therefore in some embodiments configured to print an image or logo on a ground surface, the ground printer housing a plurality of print cartridges containing a material for deposition, the material for deposition contained within each print cartridge being an ink or paint selected from a cyan, magenta, yellow, black, white, green, blue, or red colour, the image or logo optionally being an advertising logo, design or safety warning. In various embodiments, the material for deposition is a marking material such as a paint, ink, coloured material, or powder. Features described in the preceding description may be used in combinations other than the combinations explicitly described.

Although functions have been described with reference to certain features, those functions may be performable by other features whether described or not.

Although features have been described with reference to certain embodiments, those features may also be present in other embodiments whether described or not.

Whilst endeavoring in the foregoing specification to draw attention to those features of the invention believed to be of particular importance it should be understood that the Applicant claims protection in respect of any patentable feature or combination of features hereinbefore referred to and/or shown in the drawings whether or not particular emphasis has been placed thereon.