The present invention relates to a device and method for autonomous lubrication of machinery, including machinery reservoirs, with the purpose of making lubrication of machinery in inconvenient locations less difficult. This may lead to more frequent and proper lubrication and thereby less downtime due to repair and more efficient production.

Background of invention

Machines need lubrication in order to function properly and efficiently. Industrial machinery is often subjected to high loads and harsh environments in which cases lubrication is critical for continued production. Improper lubrication and lack of routine maintenance may lead to premature failure that can stop the production, leading to down-time and huge costs for lost productivity and repair of equipment. Therefore, maintenance through frequent inspection and lubrication is important to ensure that the machinery is running at its highest capacity and efficiency.

One example of machinery needing regular maintenance in the form of lubrication is cement plants which operate under severe conditions such as extreme temperatures and pressures. Components such as bearings and gears in rotary kilns, mills, conveyors, roller presses and crushers are continuously subjected to wear, making frequent and proper lubrication essential. Equipment may suffer from infrequent lubrication because the distance between the equipment is large and the equipment is located high above the ground. Such inconvenience makes maintenance more difficult, time consuming and expensive, which in turn makes improper lubrication more likely. The use of centralised greasing systems, whereby a centrally located reservoir feeding numerous points through pipework, can sometimes be considered, but the pipe runs could potentially be very long, so a number of these would have to be considered.

Other types of equipment may likewise be inconvenient for lubrication and

maintenance. These types of equipment include diggers and excavators for e.g. the mining industry. Such excavators can be very large and may need maintenance at potentially dangerous locations. The equipment may also be cranes for use at e.g. harbours and construction work. Maintenance work and lubrication may then take place high above the ground. Additionally, equipment such as dump trucks, trains, ships and oil rigs are other examples of machinery that may need lubrication and other maintenance in potentially dangerous locations.

Another example of inconveniently located machinery is wind turbines. The equipment in this high-growth, rapidly evolving industry is exposed to extreme temperatures, load weights and bearing wear. Many failures are a consequence of gearbox bearing failure. This type of failure is believed to be directly related to poor lubrication and lack of frequent maintenance. Improper lubrication accounts for around 40% of all bearing failures, and in the wind industry gear box failure is one of the most common reasons for down time and huge repair costs. The bearings in a wind turbine must take extremely high loads, and throughout the equipment, the performance criteria of the bearing will be different. Therefore, the different components pose very different requirements regarding lubrication. The main bearing rotates slowly but is subject to high loads and vibration. The generator bearing, by contrast, needs to cope with high speeds and high temperatures. Yaw bearings and pitch bearings also operate under different conditions. The generator bearings, blade bearings and main drive bearing as well as the gearbox and yaw and pitch drives all require lubrication. The very different operating conditions of the different parts of the wind turbine mean that several different lubricants may be necessary in order for the wind turbine to function optimally. For the operator this means that he has to spend a lot of resources on logistics and storage, plus an increased risk of lubricants being mixed up. Most turbines are still lubricated manually, so service technicians have to carry a variety of lubricants.

Repairing wind turbines can be difficult for several reasons. Most wind farms are in remote areas, either land based or offshore wind farms, and workers are faced with making repairs while situated very high above the ground. The worker will have to gain access up the tower via an internal ladder (or elevator in some cases), which is demanding and specialized work.

As evident from the abovementioned examples, lubrication of machinery can be very impractical and may lead to infrequent and improper maintenance. Semi-automatic lubrication systems have been developed where lubricant is either dispensed at fixed intervals or when a sensor indicates low level. Regardless of whether the lubrication is needed due to predicted and scheduled service or due to sensor indications, manual work is needed to some degree when lubricating the equipment. Therefore, it is desirable to have a means of lubricating inconveniently located machinery in a non- manual fashion such that a worker does not have to access the location. This will reduce the labour requirement, lower the risk of improper lubrication and possibly lead to reduced downtime due to improper maintenance.

Summary of invention

Autonomous or semi-autonomous devices are known in the art with the purpose of surveillance, inspection, search and rescue, cinematography and border control.

However, none of these solutions can complete the task of maintenance. The present invention is able to autonomously find the machinery needing maintenance, establish a connection to the machinery and transfer the required lubricant to the machinery. This eliminates the need for a worker to directly access the machinery when performing maintenance. In many cases such equipment is in dangerous locations, for example high above the ground or in harsh environments. The present invention means that the worker will not have to access the dangerous location and will thus improve the safety of the maintenance work. Furthermore, the risk of transferring the wrong lubricant when handling several different lubricants is greatly reduced. It is also likely that the machinery may continue to operate during maintenance while this would not be possible otherwise. For example, when performing maintenance on cranes or specifically wind turbines, production is shut down during maintenance for safety reasons as the worker needs to access the nacelle on top of the tower. In the case of an unmanned vehicle, such as a drone, performing maintenance, the wind turbine may continue its production as the drone connects to the turbine and transfers lubricant, thereby increasing the efficiency of the machinery. A wind turbine may comprise a machinery reservoir, such as a central lubrication system. Also in this case, the unmanned vehicle according to the present disclosure performing maintenance, may facilitate maintenance of the reservoir without interruption of the operation or production.

The abovementioned advantages are obtained through the presently disclosed invention, which relates to an unmanned vehicle configured for delivering lubricant to machinery, the vehicle may comprise a data processing unit configured for controlling the vehicle. The processing unit may preferably be further configured to receive instructions for a task. Furthermore, the vehicle comprises at least one container for holding the lubricant, and a tube configured for connecting the container to the machinery. The vehicle further comprises a pump configured for transferring the lubricant from the container to the machinery. A tube may be understood to be channel or a passage for conveying a fluid. Exemplary embodiments of a tube include a hose or a pipe. The tube may be flexible. Hence, the tube configured for connecting the container to the machinery may preferably be flexible. Preferably, the tube is further configured to attach to a lubrication inlet of a piece of machinery, such as a wind turbine. The tube may comprise a connection piece at the distal end, said connection piece enabling the connection of the tube to the lubrication inlet. Once connected, a fluid connection is established between the container 1 1 enclosed in the vehicle and a container (7, 8) or a reservoir inside the machinery, exemplified in Fig. 2, such that lubricant may be transferred from the unmanned vehicle to the container/reservoir of the machinery.

A first aspect of the present disclosure relates to an unmanned vehicle configured for delivering lubricant to machinery, the vehicle comprising:

- a data processing unit configured for controlling the vehicle,

- at least one container for holding the lubricant,

- a tube configured for connecting to a lubrication inlet of the machinery, such that a fluid connection is established between the container and the lubrication inlet, and

- a pump configured for transferring the lubricant from the container to the machinery via the lubrication inlet.

In a preferred embodiment, the vehicle is configured for delivering lubricant to a machinery reservoir, such as a central lubrication system of a wind turbine. In another preferred embodiment, the vehicle is configured for delivering lubricant to a machinery, such as a crane.

The present disclosure further relates to a method for delivering lubricant to machinery, including to a machinery reservoir, using an unmanned vehicle. The method comprises manoeuvring the vehicle close to the machinery that needs lubricant, identifying the machinery and/or lubrication/oil inlet for verification purpose, connecting the vehicle to a lubricant/oil inlet on the machinery, pumping lubricant from the vehicle to the machinery through the inlet, disconnecting the vehicle from the lubricant inlet, and optionally proceeding to the next machinery that needs lubricant or returning to a lubricant station or a charging station. A second aspect of the present disclosure relates to a method for delivering lubricant to machinery using an unmanned vehicle, the method comprising:

- manoeuvring the vehicle close to the machinery that needs lubricant,

- identifying the machinery and/or a lubrication inlet for verification purpose,

- connecting the vehicle to a lubricantion inlet on the machinery,

pumping lubricant from the vehicle to the machinery through the lubrication inlet,

- disconnecting the vehicle from the lubrication inlet, and

- optionally proceeding to the next machinery that needs lubricant or returning to a lubricant station or a charging station.

In a preferred embodiment, the lubrication inlet is a machinery reservoir inlet, such as an inlet for a central lubrication system.

Description of drawings

Fig. 1 shows one embodiment of the invention, wherein the vehicle is a multirotor drone hovering close to the nacelle of a wind turbine.

Fig. 2 shows an embodiment where a multirotor drone is hovering above the nacelle of a wind turbine while transferring lubricant to the wind turbine. The drone has a tube for connecting a container in the drone to a container in the wind turbine. Lubricant inlets are located on the outside of the nacelle of the wind turbine such that the drone can connect from outside the wind turbine.

Fig. 3 shows another embodiment of the invention, wherein the vehicle is a drone configured for landing on the machinery prior to transferring the lubricant.

Fig. 4 shows an embodiment of the invention, wherein the at least one container of the vehicle is refilled at a lubrication station (Fig. 4A), and wherein the at least one container is changed at a lubrication station (Fig. 4B).

Detailed description of the invention

The present disclosure relates to an unmanned vehicle for autonomous lubrication of machinery in inconvenient locations. In a preferred embodiment, the vehicle is an air- based vehicle such as a multirotor drone. This configuration is advantageous in most cases as the vehicle can then quickly move through even impassable terrain in order to access the machinery or the machinery reservoir. Additionally, the vehicle is not limited to machinery close to the ground, but can easily access machinery high above the ground, such as a crane or a wind turbine.

In another embodiment, the vehicle is a land-based vehicle or a water-based vehicle. In this case, the vehicle advantageously comprises mobility means and/or manoeuvring means such as wheels, caterpillars, paddles, and/or screws. This may be a more convenient and cheaper solution for less demanding tasks. In an embodiment of the disclosure, the vehicle is selected from the group of; an air-based vehicle such as a multirotor drone, a land-based vehicle and a water-based vehicle, and combinations thereof.

More specifically, the vehicle may be a combined air-based vehicle, and/or land-based vehicle, and/or water-based vehicle. Thus, the vehicle comprises two or more mobility means selected from the group of: propellers, rotors, airscrews, wheels, caterpillars, paddles, and screws. For example, the vehicle may be multirotor drone further provided with wheels, such that the drone may be first transported by air to a target site above the ground, and then at the target site, the vehicle is maneuvered into a target position by wheels. Hence, a combined vehicle has the advantage of improving the flexibility and precision for accessing the machinery or the machinery reservoir.

A machinery may comprise an internal, central reservoir providing lubricant for one or more sites or locations on the machine. This is also referred to as a central lubrication system (CLS), or centralized lubrication/grease/oil system. The system delivers controlled amounts of lubricant to multiple locations on the machine, while the machine is operating, and the system may be fully automated or activated via a manual pump. For example, the system may be configured to apply lubricant continuously, or in small, measured amounts over short, frequent time intervals at a first site, and/or configured to apply lubricant in larger amounts with longer time intervals at a second site. Thus, a central lubrication system has the advantage of reducing the amount of maintenance, as well as reducing the risk of contamination from the external vehicle.

Advantageously, the vehicle of the present disclosure may provide maintenance of externally accessible machinery sites, and/or maintenance of an internally, central reservoir of the machinery.

In an embodiment of the disclosure, the vehicle is configured for delivering lubricant to a machinery reservoir, such as a central lubrication system. In case one or more container(s) becomes empty during lubrication, the vehicle should move to a lubrication station to either change or refill the empty container(s). Therefore, in one embodiment the vehicle is configured for moving to a lubricant station when at least one container is empty in order to change and/or refill the container(s). Figure 4 shows an embodiment of according to the present disclosure where the at least one container of the vehicle is refilled and/or changed at a lubricant station. Figure 4A shows an embodiment, wherein the at least one container of the vehicle is refilled at a lubrication station, Figure 4B shows an embodiment wherein the at least one container is changed at a lubricant station.

It is very important that the correct type of lubrication is used for the different parts of the machinery. Improper lubrication leads to more wear and in some cases failure of the improperly lubricated part. Therefore, in one embodiment communication between the machinery and the unmanned vehicle is established prior to lubrication in order to ensure that the vehicle is connected to the correct lubricant inlet and provides the correct type and/or amount of lubricant needed. In another embodiment the type and/or amount of lubrication needed is pre-programmed.

The vehicle is configured to carry lubricant in at least one container. Lubricant may be understood to be a substance capable of reducing friction and/or wear when introduced between solid surfaces. Examples of lubricant include grease and oil. Various types of lubricant may be compatible with the presently disclosed vehicle. In one embodiment the vehicle is configured to carry a single type of lubricant. In some cases, e.g. for machinery using a single type of lubricant, this will be sufficient and may furthermore keep the weight and complexity of the vehicle down. In another embodiment, the vehicle is configured to carry a plurality of types of lubricant. This may be necessary for machinery requiring multiple types of lubricant or for situations where the vehicle provides lubrication to more than one type of machinery before returning to a lubrication station. In yet another embodiment the container for holding the lubricant is changeable. This is advantageous for cases where new lubricant should be loaded onto the vehicle quickly and especially for when a different kind of lubricant is needed. Alternatively, the container for holding the lubricant is refillable. In a further embodiment the container for holding the lubricant is built into the vehicle. The container for holding the lubricant could also be external. A container built into the vehicle would normally be more suitable for refilling while an external container may also be suited for changing the container. When the vehicle reaches the machinery, it may connect to a lubricant inlet before starting the transfer of lubricant. Therefore, in one embodiment the connection procedure is accomplished with the help of at least one magnet. Alternatively, the connection procedure is accomplished with the help of at least one electromagnet. The use of an electromagnet could be advantageous as this allows for the coupling procedure to be controlled by the current in the electromagnet.

In one embodiment of the invention the vehicle is loaded manually. In a preferred embodiment, the vehicle is loaded automatically. This will reduce the manual work requirement and lower the risk of loading the vehicle with a wrong kind of lubricant/oil.

The unmanned vehicle may also be used for collecting liquid from machinery and bring it to another location. This is useful e.g. for changing oil on equipment that is inconveniently located. One example is a wind turbine that needs to have the transmission oil changed. Therefore, in one embodiment of the invention the vehicle is further configured for pumping liquid from the machinery, such as from the machinery reservoir, and into the container, for example when changing oil.

The unmanned vehicle is useful for lubricating a variety of machinery, e.g. cement factories and wind turbines. Because the vehicle may be very versatile and can access inconvenient locations, it is also useful for lubricating other types of machinery.

Therefore, in a further embodiment the vehicle is configured for lubricating machinery in motion, for example a train, a truck, a crane, or wind turbine blades. The vehicle may also be used for lubricating parked vehicles.

In one embodiment, the vehicle is a drone, which is a fast and versatile means for transporting lubricant/oil. Advantageously, the drone connects to the machinery such that a fluid connection is established for transferring the lubricant. Preferably, the drone is configured for landing prior to pumping the lubricant. In one embodiment the drone is furthermore secured to the machinery after landing. Landing and securing a drone prior to transferring the lubricant/oil is advantageous as it prolongs the operational time of the drone due to less battery/fuel usage and lowers the risk of any unintended events during transfer. In some cases, it may be impractical or not even possible for the drone to land when transferring the lubricant. In such cases the drone may connect to the machinery and transfer lubricant/oil while the drone is hovering. The vehicle may be configured to perform various types of motion such as flying, rolling, walking, or combinations thereof. Hence, the vehicle may initially fly e.g. from a lubrication station to a machinery and subsequently land on the machinery, e.g. on the nacelle of a wind turbine. Next, the vehicle may perform a rolling motion or a walking motion in order to reach the relevant position, typically a position wherefrom the lubrication inlets are reachable by the vehicle. The vehicle may then connect the tube 5 to one or more of the lubrication inlets 6 to deliver lubricant to the machinery as described elsewhere in the application. The vehicle may comprise one or more suction cups for creating a partial vacuum such that the vehicle can adhere to the surface of the machinery. The one or more suction cups may form part of the landing gear.

The vehicle preferably comprises an energy storage device such as a battery or a plurality of batteries. The energy storage device powers the vehicle, e.g. rotors of the vehicle and/or the processing unit of the vehicle. The vehicle may further comprise solar cells configured for charging the energy storage device. Alternatively or additionally, the vehicle may be charged by a charging station, said charging station provided on the machinery (e.g. the wind turbine) or at a separate location.

The vehicle may comprise a communication unit configured for wirelessly receiving information such as weather information. The information may be provided by an external service, e.g. a remote server. The communication unit may be configured to wirelessly connect to the internet via a broadband cellular network technology such as 4G, 4G LTE, 5G, or other similar technologies. Hence, the vehicle may receive information from the internet such as information about the weather (wind speed, rain, etc.). The vehicle may further comprise an anemometer configured for measuring the speed and/or the direction of the wind. The processing unit of the vehicle may be configured to adaptively control the vehicle based on the received weather information. The vehicle may also autonomously perform decisions on which routes to take based on weather information. It may also decide to stay in a base, such as a charging station, in case the wind speed exceeds a certain threshold.

The unmanned vehicle needs to be large enough to carry a substantial amount of lubricant/oil and yet small enough to be able to manoeuvre close to the part of the machinery that needs lubrication/oil. In one embodiment, the weight of the unmanned vehicle is 2-3 kg, or 3-4 kg, or 4-5 kg, or 5-6 kg, or 6-7 kg, or 7-8 kg, or 8-10 kg, or 10- 12 kg. In another embodiment, the weight of the unmanned vehicle is between 2 kg and 10 kg, or between 2.5 kg and 8 kg, or between 3 kg and 7 kg, or between 3.5 kg and 6 kg, or between 4 kg and 5 kg. In yet another embodiment the volume of the container(s) for the lubricant/oil is 250-500 ml_, or 500-750 ml_, or 750-1000 ml_, or 1000-1500 ml_, or 1500-2000 ml_, or 2000-2500 ml_, or 2500-3000 ml_. In yet another embodiment the volume of the container(s) for the lubricant/oil is between 250 ml. and 2500 ml_, or between 500 ml. and 2000 ml_, or between 750 ml. and 1750 ml_, or between 1000 ml. and 1500 ml_.

The present disclosure further relates to a method for delivering lubricant to machinery, including machinery reservoirs, using an unmanned vehicle. In one embodiment of this method communication between the machinery and the unmanned vehicle is established prior to lubrication in order to ensure that the vehicle is connected to the correct lubricant inlet and provides the correct type and/or amount of lubricant needed. In another embodiment of the method the type and/or amount of lubrication and/or oil needed is pre-programmed.

The vehicle is preferably configured such that the amount of lubricant in the

container(s) is known. In one embodiment of the method the vehicle is configured for moving to a lubricant station when at least one container is empty in order to change and/or refill the container(s).

Advantageously, the vehicle is configured for performing a coupling procedure prior to transferring the lubricant in order to establish a safe connection to the machinery. Such a coupling procedure may be performed in various ways. In one embodiment of the method the coupling procedure is accomplished with the help of at least one magnet. In another embodiment of the method the coupling procedure is accomplished with the help of at least one electromagnet. The electromagnet may be controlled by varying the current flowing in the electromagnet such that the coupling procedure in some embodiments is controlled and assisted by this. Thereby, the coupling and decoupling may be carried out effortlessly without the vehicle having to apply force to the magnet(s) when decoupling from the machinery. Loading the unmanned vehicle may be accomplished by manually changing/refilling the container(s). Preferably loading the vehicle is accomplished by an automatic system for changing/refilling the container(s).

As mentioned earlier, it is conceivable that the vehicle should pump liquid, such as oil, from the machinery into at least one container on the vehicle. Therefore, on a further embodiment of the invention the method further comprises the step of pumping liquid from the machinery into the container, for example when changing oil.

The method of using an unmanned vehicle for lubricating machinery may be useful for a broad range of applications. This allows lubrication of machinery normally not accessible for maintenance. This could in some cases be vehicles in motion.

Therefore, in such embodiments of the method the vehicle is configured for lubricating machinery in motion, for example a train, a truck, a crane, or a wind turbine blade. The method may also include lubrication of parked vehicles. Lubrication of vehicles in motion means that they can continue operating during lubrication maintenance, meaning that the vehicle has less down time.

In some cases it is beneficial if the vehicle is a drone as it can reach otherwise inaccessible machinery e.g. at locations high above the ground. Moreover, it may be advantageous for the drone to land prior to transfer of lubricant. Therefore, in a preferred embodiment of the method, the vehicle is a drone configured for landing prior to pumping the lubricant. The method may further be improved in some embodiments by having the drone secured to the machinery after landing.

Detailed description of the drawings

Fig. 1 shows one embodiment of the invention where the unmanned vehicle is a multirotor drone 1. The drone 1 is hovering above the nacelle 2 of a wind turbine. The drone may in one embodiment be configured for connecting to the wind turbine and transfer lubricant while hovering above the wind turbine. In another embodiment, the drone is configured for landing prior to transferring the lubricant.

Fig. 2 shows one embodiment where the unmanned vehicle is a drone 1 hovering close to the nacelle 2 of a wind turbine. The drone 1 is a multirotor drone with four rotors 3 and landing gear 4 attached to the bottom. A tube 5 for transferring the lubricant connects a container in the drone 1 with a container 7 in the wind turbine. The tube 5 is connected to a lubrication inlet 6 on the nacelle 2. In this embodiment, a first container 7 and a second container 8 with lubricant are located inside the nacelle 2. In an embodiment, the first and/or second container inside the nacelle is a central lubrication system. Tubes or pipes 9 connect the lubrication inlets 6 with the first 7 and second 8 containers. Fig. 3 shows another embodiment of the invention where the unmanned vehicle is a multirotor drone 1 configured for landing on the nacelle 2 of a wind turbine prior to transferring the lubricant to the wind turbine.

Fig. 4 shows an embodiment of according to the present disclosure where the at least one container of the vehicle is refilled and/or changed at a lubricant/lubrication station 10. Figure 4A shows an embodiment, where at least one container 11 of the vehicle is refilled at a lubrication station via a tube 12 in the same manner as a car is refilled at a petrol tank. The lubrication station comprises one or more reservoirs of lubricant, and the container of the vehicle is refilled by forming a fluid connection between the container and the station reservoir, said fluid connection preferably enabled by a detachable tube, which may be attached/detached from the vehicle and/or the lubrication station. The fluid connection may be formed when the vehicle is adjacent to the lubrication station, such as air-based adjacently above the lubrication station as exemplified in Figure 4A, or land-based adjacently to the lubrication station as exemplified in Figure 4B.

Figure 4B further shows an embodiment where the at least one container is changed at a lubricant station in the same manner as a cartridge replacement. The lubrication station comprises one or more containers, and the at least one container of the vehicle is removed and replaced with a new container from the lubrication station. Preferably, the used/empty container is temporarily disposed at the lubrication station for easy disposal.

Further details of the invention

The following list of items should not be construed as claims.

1 . An unmanned vehicle configured for delivering lubricant to machinery, the vehicle comprising:

- a data processing unit configured for controlling the vehicle and for receiving instructions for the task,

- at least one container for holding the lubricant,

- a tube configured for connecting the container to the machinery, and

- a pump configured for transferring the lubricant from the container to the machinery. 2. The unmanned vehicle according to item 1 , wherein the vehicle is configured for delivering lubricant to a machinery reservoir, such as a central lubrication system.

3. The unmanned vehicle according to any of the preceding items, wherein the vehicle is selected from the group of; an air-based vehicle such as a multirotor drone, a land-based vehicle and a water-based vehicle, and combinations thereof.

4. The unmanned vehicle according to any of the preceding items, wherein the vehicle is configured for moving to a lubricant station when at least one container is empty in order to change and/or refill the container(s).

5. The unmanned vehicle according to any of the preceding items, wherein

communication between the machinery and the unmanned vehicle is established prior to lubrication in order to ensure that the vehicle is connected to the correct lubricant inlet and provides the correct type and/or amount of lubricant needed.

6. The unmanned vehicle according to any of the preceding items, wherein the type and/or amount of lubrication and/or oil needed is pre-programmed. 7. The unmanned vehicle according to any of the preceding items, wherein the vehicle is configured to carry a single type of lubricant.

8. The unmanned vehicle according to any of the preceding items, wherein the vehicle is configured to carry a plurality of types of lubricant.

9. The unmanned vehicle according to any of the preceding items, wherein the

container for holding the lubricant is built into the vehicle.

10. The unmanned vehicle according to any of the preceding items, wherein the

container for holding the lubricant is external.

1 1 . The unmanned vehicle according to any of the preceding items, wherein the

container for holding the lubricant is changeable. 12. The unmanned vehicle according to any of the preceding items, wherein the container for holding the lubricant is refillable.

13. The unmanned vehicle according to any of the preceding items, wherein the

connection procedure is accomplished with the help of at least one magnet.

14. The unmanned vehicle according to any of the preceding items, wherein the

connection procedure is accomplished with the help of at least one electromagnet.

15. The unmanned vehicle according to any of the preceding items, wherein the vehicle is loaded manually.

16. The unmanned vehicle according to any of the preceding items, wherein the vehicle is loaded automatically.

17. The unmanned vehicle according to any of the preceding items, further configured for pumping liquid from the machinery, such as the machinery reservoir, and into the container, for example when changing oil.

18. The unmanned vehicle according to any of the preceding items, wherein the vehicle is configured for lubricating machinery in motion, for example a train, a truck, a crane, or wind turbine blades.

19. The unmanned vehicle according to any of the preceding items, wherein the vehicle is a drone configured for landing prior to pumping the lubricant.

20. The unmanned vehicle according to item 19, wherein the drone is secured to the machinery after landing.

21. The unmanned vehicle according to any of the preceding items, wherein the weight of the unmanned vehicle is 2-3 kg, or 3-4 kg, or 4-5 kg, or 5-6 kg, or 6-7 kg, or 7-8 kg, or 8-10 kg, or 10-12 kg.

22. The unmanned vehicle according to any of the preceding items, wherein the weight of the unmanned vehicle is between 2 kg and 10 kg, or between 2.5 kg and 8 kg, or between 3 kg and 7 kg, or between 3.5 kg and 6 kg, or between 4 kg and 5 kg. The unmanned vehicle according to any of the preceding items, wherein the volume of the container(s) for the lubricant/oil is 250-500 ml_, or 500-750 ml_, or 750-1000 ml_, or 1000-1500 ml_, or 1500-2000 ml_, or 2000-2500 ml_, or 2500-3000 ml_. The unmanned vehicle according to any of the preceding items, wherein the volume of the container(s) for the lubricant/oil is between 250 ml. and 2500 ml_, or between 500 ml. and 2000 ml_, or between 750 ml. and 1750 ml_, or between 1000 ml. and 1500 ml_. A method for delivering lubricant to machinery using an unmanned vehicle, the method comprising:

- manoeuvring the vehicle close to the machinery that needs lubricant,

- identifying the machinery and/or lubrication/oil inlet for verification purpose, connecting the vehicle to a lubricant/oil inlet on the machinery,

pumping lubricant from the vehicle to the machinery through the inlet, disconnecting the vehicle from the lubricant inlet, and

- proceeding to the next machinery that needs lubricant or returning to a lubricant station or a charging station. The method according to item 25, wherein the inlet is a machinery reservoir inlet, such as an inlet for a central lubrication system. The method according to any of items 25-26, wherein communication between the machinery and the unmanned vehicle is established prior to lubrication in order to ensure that the vehicle is connected to the correct lubricant inlet and provides the correct type and/or amount of lubricant needed. The method according to any of items 25-27, wherein the type and/or amount of lubrication and/or oil needed is pre-programmed. The method according to any of items 25-28, wherein the vehicle is configured for moving to a lubricant station when at least one container is empty in order to change and/or refill the container(s).

30. The method according to any of items 25-29, wherein the coupling procedure is accomplished with the help of at least one magnet.

31. The method according to any of items 25-30, wherein the coupling procedure is accomplished with the help of at least one electromagnet.

32. The method according to any of items 25-31 , wherein the vehicle is loaded

manually.

33. The method according to any of items 25-32, wherein the vehicle is loaded

automatically.

34. The method according to any of items 25-33, further comprising the step of

pumping liquid from the machinery, such as the machinery reservoir, and into the container, for example when changing oil.

35. The method according to any of items 25-34, wherein the vehicle is configured for lubricating machinery in motion, for example a train, a truck, a crane, or a wind turbine blade.

36. The method according to any of items 25-35, wherein the vehicle is a drone

configured for landing prior to pumping the lubricant.

37. The method according to item 36, wherein the drone is secured to the machinery after landing.