Autonomous mowing vehicle

Abstract

An autonomous mowing vehicle 1000 comprises a body portion 400; a mower unit 100, the mower unit connected to the body portion; a pair of wheels 200, each wheel connected to the body portion, wherein

Description

Field of the Disclosure The present invention relates to an autonomous vehicle, in particular an autonomous mowing vehicle. Background Mowing vehicles are designed to cut grass to a uniform height, keeping lawns neat and well-maintained. They typically use one or more blades or other cutting means to trim the grass as the mowing vehicle is pushed or driven, with most mowing vehicles offering adjustable height settings to control how short or long the grass is cut. This capability allows users to achieve their desired lawn appearance, whether for aesthetic reasons or to support healthy grass growth. Mowing vehicles, such as lawnmowers, are used for residential lawns and parks. Mowing vehicles are also essential for the maintenance of sports pitches. On these fields, the mower’s wheels create visible lines or patterns that serve both aesthetic and functional purposes. These stripes help groundskeepers monitor the uniformity of the cut and contribute to the field’s neat, professional look, which is essential for games and events. However, uneven ground can cause these wheel marks to appear patchy or irregular, especially when using two-wheel mowers. The concentrated weight on just two wheels can lead to deeper, more pronounced tracks, and any shifts or tilts due to an uneven surface can result in inconsistent lines. This inconsistency can disrupt the clean, striped appearance that is crucial for a well-groomed sports pitch or garden. Further inconsistency in the lines in a lawn can be observed after mowing where the wheels of the mower are sub-optimally arranged such that the wheels of the mower contact the lawn to a different degree in different areas. As such there is need for an improved mowing and turf maintenance vehicle. Summary According to an aspect of the present invention there is provided an autonomous mowing vehicle comprising: a body portion; a mower unit, the mower unit connected to the body portion; a pair of wheels, each wheel connected to the body portion, wherein the wheels are configured to be driven independently of one another; and a roller comprising a longitudinal axis, the roller connected to the body portion via a connection mechanism such that the roller can rotate around a first axis, wherein the first axis is perpendicular to the longitudinal axis, wherein the pair of wheels is connected to the body portion between the mower unit and the roller, wherein each wheel comprises a wheel contact portion, wherein the wheel contact portion is configured to be in contact with a ground plane, wherein the roller comprises a roller contact portion, wherein the roller contact portion is configured to be in contact with the ground plane, wherein the longitudinal axis is parallel to the ground plane and spaced from the ground plane by a first distance, wherein the first axis is perpendicular to the ground plane, and wherein the wheel contact portions are separated by a distance D, wherein the roller contact portion has a length L, and wherein L is greater than D minus 70mm. As such, the mowing vehicle is designed to operate autonomously and create neat, uniform lines on a mowed lawn, park or sports pitch. The ground plane in the context of the autonomous mowing vehicle is the surface of the grass or other terrain the mowing vehicle moves over. The ground plane is the flat or uneven ground that the pair of wheels and the roller roll on. The mower unit cuts in a plane parallel to the ground plane, and the mower’s cutting height may be adjustable by raising or lowering the mower blades. By adjusting the distance between the mower blades and the ground plane, the length of grass being mowed can be altered. Preferably, the connection mechanism is configured to allow the roller to rotate 360° around the first axis. As such, the roller is configured for maximum manoeuvrability and ease of movement in any direction. Preferably, the connection mechanism is configured such that the roller can rotate around a second axis, and the second axis is perpendicular to both the longitudinal axis and the first axis. As such, the roller is able to maintain contact with uneven or undulating ground for improved stability. As such, the roller is configured to produce an even, continuous stripe of rolled grass without gaps or interruptions. Preferably, the first axis is closer to the mower unit than the longitudinal axis in a distance measured in the ground plane. In this configuration, wobbling and / or oscillation of the roller during the mowing process is minimised and the stability of the autonomous mowing vehicle is enhanced for smoother, more accurate movement. Preferably, the distance between the first axis and the longitudinal axis in the ground plane is at least 120mm. As such, the distance between the first axis and the longitudinal axis in the ground plane is optimised such that the wobbling and / or oscillation of the roller is minimised and the stability of the autonomous mowing vehicle is further optimised. Preferably, the roller is releasably attachable to the body in a plurality of positions such that the distance between the first axis and the longitudinal axis in the ground plane is adjustable. As such, the distance between the first axis and the longitudinal axis in the ground plane can be adjusted and optimised according to requirements. Preferably, the outer edges of the wheel contact portions of the pair of wheels are separated by a distance Y and the length L is greater than the distance Y. As such the roller is configured to create clean, professional-looking stripes by effectively masking the wheel tracks within the rolled pattern. Preferably, the outer edges of the wheel contact portions of the pair of wheels are separated by a distance Y and the length L is less than the distance Y. As such, the roller is configured to create clean, professional-looking stripes by effectively integrating the wheel pattern into the overall rolled design. Preferably the mower unit has a width W, and the width W is less than the distance Y. As such, the roller is configured to create clean, professional-looking stripes, with the wider roller pattern encompassing the narrower mower pattern. Preferably the roller contact portion comprises one roller contact portion segment. A single roller contact portion simplifies the design and reduces maintenance while providing a consistent stripe across the lawn. Preferably, the roller contact portion comprises a plurality of roller contact portion segments, and each roller contact point segment has substantially the same length. In this way, the roller is configured to provide multiple stripes across the lawn. Preferably, the roller contract portion comprises a plurality of roller contact portion segments, and the roller contact portion segments are separated by less than 35mm. In this way, the roller is configured to provide uniform stripes across the lawn. Preferably the first axis is equidistance from each pair of the wheels. In this way, the distance between the stripe created by the roller contact portion and the stripe created by the wheel contact portions are equidistant. As such, the autonomous mowing vehicle is configured to create uniform stripes across the lawn. Preferably the mower unit is connected to the body portion via an arm. As such, the mower unit is able to move flexibly in relation to the body portion. Preferably the arm is configured such that the mower unit may be raised from a first mowing position to a second storage position. As such, the mower unit can easily transition between a mowing position and a storage position, allowing it to avoid obstacles and be securely stored when not in use. Preferably the diameter of the roller is less than the diameter of a wheel of the pair of wheels. As such, the mowing vehicle is configured for stability and balance. Preferably the connection mechanism lies on a central plane of the body portion. As such, the roller is balanced, ensuring even pressure distribution and consistent rolling. Preferably the roller comprises one or more materials selected from a group of materials consisting of: steel, plastic and concrete. As such, the roller is optimised for durability and weight. Preferably the roller comprises a cavity for receiving a ballast. As such, the roller weight is adjustable, as the cavity may be filled to enhance stripe definition and emptied for easier transportation. Preferably the autonomous mowing vehicle further comprises an engine, wherein the engine is configured to power the autonomous mowing vehicle. As such, the mowing vehicle can cut grass quickly and consistently with no manual input. Preferably the autonomous mowing vehicle further comprises a drive system, wherein the drive system is configured to transfer power from the engine to the pair of wheels to propel the autonomous mowing vehicle. As such, the mowing vehicle is configured to be propelled with no manual input. Preferably the autonomous mowing vehicle further comprises a control system, wherein the control system is configured to operatively connect to the drive system for regulating the speed and direction of the autonomous mowing vehicle. As such, the mowing vehicle is configured to adjust speed and direction with no manual input. Preferably the engine is an engine selected from a group of engines consisting of: petrol engines, diesel engines and electric engines. As such, the mowing vehicle is be configured for flexibility in power sources, with options for high power, fuel efficiency, or eco-friendly performance. Brief Description of the Drawings Aspects of the present invention will now be described by way of example only and with reference to the accompanying drawings, in which: Figure 1 illustrates the autonomous mowing vehicle of the present invention; Figure 2 illustrates an alternative view of the autonomous mowing vehicle of the present invention; Figure 3 illustrates a bottom-up view of the autonomous mowing vehicle of the present invention; Figure 4 illustrates a bottom-up view of the autonomous mowing vehicle of the present invention; Figure 5 illustrates an end view of the autonomous mowing vehicle of the present invention; and Figure 6 illustrates an alternative view of the autonomous mowing vehicle of the present invention. Detailed Description With reference to Figure 1, there is illustrated the autonomous mowing vehicle 1000 of the present invention. The mowing vehicle 1000 includes: a mower unit 100, a pair of wheels 200, a roller 300, and a body portion 400. The mower unit 100, the pair of wheels 200 and the roller 300 are each connected to the body portion 400. The roller 100 is connected to the body portion 400 via a connection mechanism 500. The pair of wheels 200 are connected to the body portion 400 between the mower unit 100 and the roller 300. The mower unit 100 includes one or more blades that are configured to mow grass. The pair of wheels 200 are configured to propel and steer the autonomous mowing vehicle 1000, and the roller 300 is configured to bend grass that has been mowed by the mower unit 100. With reference to Figure 2, an example embodiment of the autonomous mowing vehicle 1000 is illustrated. The roller 300 has a longitudinal axis 320. The roller 300 is connected to the body portion 400 via the connection mechanism 500. The roller 300 is connected to the body portion 400 such that the roller 300 can rotate around a first axis 340, wherein the first axis 340 is perpendicular to the longitudinal axis 320. In the illustrated example, the connection mechanism 500 includes a caster and the connection mechanism 500 is configured to allow the roller 300 to rotate 360° around the first axis 340. Each wheel of the pair of wheels 200 are also configured to rotate independently, such that the pair of wheels 200 can steer the mowing vehicle 1000 in any direction. In the illustrated example, the roller 300 is facing in the same direction as the pair of wheels 200 and the mowing vehicle 1000 is configured to be directed in a straight direction. In Figure 2, the autonomous mowing vehicle 1000 is illustrated from a rear angle. The autonomous mowing vehicle 1000 is configured such that it may move in a forward direction, away from the position in which it is illustrated, as well as in a reverse direction back towards that position. As such, the pair of wheels 200 and the roller 300 are each configured to roll in a forward direction, and in a reverse direction. Furthermore, the connection mechanism 500 is configured to allow the roller 300 to rotate around a second axis 360, wherein the second axis 360 is perpendicular to the longitudinal axis 320 and the first axis 340. The roller 300 being able to rotate around the second axis 360 means that the roller 300 is configured to be able to tilt relative to the body portion 400. The tilting ability of the roller 300 allows the roller 300 to adjust itself if it encounters uneven or undulating ground. With reference to Figure 3, a bottom-up view of an example embodiment of the autonomous mowing vehicle 1000 is illustrated. In the illustrated example, the distance between the first axis 340 and the longitudinal axis 320 in the ground plane is 120mm. The distance between the first axis and the longitudinal axis is optimised to minimise the wobbling and / or oscillation of the roller 300 and enhance the stability of the roller 300. In the illustrated example, the roller 300 is attached to the vehicle body by a plate 600. The plate 600 comprises slots that allow the position of the plate 600 to be adjusted relative to the body portion 400. As such, the distance between the first axis 340 and the longitudinal axis 320 is adjustable. In the illustrated example, the roller 300 is in a ‘fully forward’ position such that the distance between the longitudinal axis 320 and the first axis 340 is at its minimum. In an alternative embodiment (not shown) the position of the plate 600 is adjusted relative to the body portion 400 such that the roller 300 is not in a ‘fully forward’ position and the distance between the longitudinal axis 320 and the first axis 340 is greater than 120mm. In the example embodiment illustrated in Figure 3, the pair of wheels 200 are connected to the body portion and the pair of wheels 200 are closer to the mower unit 100 than they are to the roller 300. In an alternative embodiment (not shown) the pair of wheels 200 are closer to the roller 300 than they are to the mower unit 100. In the example embodiment illustrated in Figure 3, each wheel of the pair of wheels 200 comprise a wheel contact portion, and the wheel contact portions are separated by a distance D, the roller 300 comprises a roller contact portion that comprises a length L, and the length L is the distance D minus 70mm. In the illustrated example, each wheel of the pair of wheels 200 lies substantially equidistant from the central plane of the body portion 400, and the mower unit 100 is centrally aligned with the central plane of the body portion 400. As such, the distance between the wheel contact portions and the roller contact portion is the same for each wheel of the pair of wheels 200. As such, in the illustrated example, the autonomous rolling vehicle is configured to create a 35mm gap between the edge of the rolled grass created by the wheel contact portion and the edge of the rolled grass created by the roller contact portion. In an alternative embodiment (not shown), the wheel contact portions are separated by a distance D and the roller contact portion has a length L that is the same as the distance D. With reference to Figure 4, a bottom-up view of an example embodiment of the autonomous mowing vehicle 1000 is illustrated. The roller 300 is configured to rotate 360° around the first axis 340 (shown in Figure 2), which is perpendicular to the longitudinal axis 320. The pair of wheels 200 are also configured to rotate, such that the pair of wheels 200, which are driven independently of one another, can steer the mowing vehicle 1000 in any direction. In Figure 4, the autonomous mowing vehicle 1000 is turning such that roller 300 is rotated around the fist axis 340 relative to the pair of wheels 200 and the mower unit 100. With reference to Figure 5, an example embodiment of the autonomous mowing vehicle 1000 viewed from the end is illustrated, the roller 300 is made of steel and has a hollow cavity designed to receive a ballast. In the illustrated example, the ballast is sand. The roller 300 is configured such that it may be filled with ballast to adjust the weight of the roller 300. When the roller cavity is filled, increased weight allows the roller to apply greater pressure to the ground. When the ballast is removed from the roller cavity, the weight of the roller 300 decreases, making the roller 300 easier to manoeuvre and reducing the pressure applied to the ground. Wth reference to Figure 5, the roller 300 is made up of five roller drums 30, wherein each of the roller drums 30 comprise a contact portion segment and each contact portion segment has substantially the same width. A gap 50 is between each pair of contact portion segments. The roller drums 30 are designed to bend the grass, while the gaps 50 are configured to produce a line of unrolled grass. The distance between the roller contact portion segments is 35mm, therefore the line of unrolled grass has a width of 35mm. In an alternative embodiment (not shown) the distance between adjacent roller contact portion segments is 0mm, therefore there is no line of unrolled grass between the roller drums 30. Wth reference to Figure 6, an example embodiment of the autonomous mowing vehicle 1000 viewed from the side is illustrated. The mower unit 100 is connected to the body portion 400 via the arm 150. In Figure 5, the arm is configured such that the mower unit 100 is in a first mowing position. In the first mowing position, the mower unit 100 is brought into a position such that it may be in physical communication with the grass that is to be cut. In a second storage position (not shown) the mower unit 100 is lifted by the arm 150. The arm 150 may be configured to move the mower unit 100 into one or more different first mowing positions and one or more different second storage positions. For example, one or more different first mowing positions may comprise positions wherein the mower unit 100 is positioned lower, such that the grass is cut to a shorter length, or wherein the mower unit 100 is position higher, such that the grass is cut to a longer length. For example, one or more different second storage positions may comprise positions wherein the mower unit 100 is positioned central to the centre plane of the body portion 400, or where the mower unit 100 is positioned displaced from the central plane of the body portion 400. With reference to Figure 6, the arm 150 extends from a front end of the body portion 400 and the pair wheels 200 and the roller 300 are connected to a lower surface of the body portion 400. In an alternative embodiment (not shown), the mower unit 100, the pair of wheels 200 and the roller 300 are each connected to a lower surface of the body portion 400. With reference to Figure 6, the diameter of the roller 300 is less than the diameter of a wheel of the pair of wheels 200. The different in the diameter of the roller 300 and the diameter of the wheel of the pair of wheels 200 is at least a 5% difference. With reference to Figure 6, the autonomous mowing vehicle 1000 has an engine (not shown) to power the autonomous mowing vehicle 1000. In Figure 6, the engine located at position 500 of the mowing vehicle 1000. The autonomous mowing vehicle 1000 includes a drive system (not shown) and a control system (not shown). The drive system is configured to transfer power from the engine to the pair of wheels 200 to propel the autonomous mowing vehicle 1000. The control system is configured to operatively connect to the drive system for regulating the speed and the direction of the autonomous mowing vehicle 1000. In Figure 6, the engine is a petrol engine. The drive system and control system configuration enable the autonomous mowing vehicle 1000 to operate without manual input. The control unit (not shown) is configured to adjust the engine output and the direction of the pair of wheels 200 to redirect the mowing vehicle 1000 when required. In use, the pair of wheels 200 are configured to propel and steer the autonomous mowing vehicle 1000 over grass that is to be mowed. When mowing is activated, the mower unit 100 is in the first mowing position and configured to be in physical communication with the glass. In use, the mower unit 100 first mows the grass, then the pair of wheels 200 and the roller 300 roll over the grass. When the roller 300 rolls over the grass, the roller 300 bends the grass. As the length of the roller contact portion is less than the distance between the wheel contact portions by a distance of less than 70mm, the mowed grass has a neat appearance. The roller 300 is configured to rotate when it encounters uneven or undulating ground. If the ground beneath the roller 300 has bumps, the roller 300 can rotate around the second axis 360 to stay in contact with the surface, maintaining stability and effective ground contact. Following the mowing of one strip of grass, the control unit will adjust the direction of the pair of wheels 200 to redirect the mowing vehicle 1000 to an area of grass to be mowed. The invention is not limited to the specific examples or structures illustrated, a greater number of components that are illustrated in the Figures could be used, for example. For example, the length L may be the same as the distance D. For example, the length L may be greater than the distance D. For example, the length L may be equal to the distance D minus 70mm, 50mm, 30mm or 10mm. For example, the distance between the first axis and the longitudinal axis in the ground plane may be 120mm to 2000mm. For example, the arm 150 may be a fixed arm and may not be configured to move the mower unit 100 into different configurations. For example, the roller 300 may comprise plastic or concreate, or any other substantially robust material. For example, the ballast may comprise broken stone or gravel. For example, the roller 300 may comprise one, two, three, four, five, six, seven, eight or more roller drums 50. For example, each roller drum 50 may have a different width. For example, some of the roller drums 50 may be the same width and some of the roller drums 50 may be different widths. For example, the autonomous mowing vehicle 1000 may comprise two pairs of wheels 200 configured to be driven independently from each other. For example, the different in the diameter of the roller 300 and the diameter of the wheel of the pair of wheels 200 may be at least a 10% difference, at least a 15% difference or at least a 20% difference.

Claims

1. An autonomous mowing vehicle comprising:a body portion;a mower unit, the mower unit connected to the body portion;a pair of wheels, each wheel connected to the body portion, wherein the wheels are configured to be driven independently of one another; anda roller comprising a longitudinal axis, the roller connected to the body portion via a connection mechanism such that the roller can rotate around a first axis, wherein the first axis is perpendicular to the longitudinal axis, wherein the pair of wheels is connected to the body portion between the mower unit and the roller,wherein each wheel comprises a wheel contact portion, wherein the wheel contact portion is configured to be in contact with a ground plane,wherein the roller comprises a roller contact portion, wherein the roller contact portion is configured to be in contact with the ground plane, wherein the longitudinal axis is parallel to the ground plane and spaced from the ground plane by a first distance,wherein the first axis is perpendicular to the ground plane, andwherein the wheel contact portions are separated by a distance D, wherein the roller contact portion has a length L, andwherein L is greater than D minus 70mm.

2. The autonomous mowing vehicle of claim 1, wherein the connection mechanism is configured to allow the roller to rotate 360° around the first axis.

3. The autonomous mowing vehicle of claim 1 or claim 2, wherein the connection mechanism is configured such that the roller can rotate around a second axis, wherein the second axis is perpendicular to both the longitudinal axis and the first axis.

4. The autonomous mowing vehicle of any preceding claim, wherein the first axis is closer to the mower unit than the longitudinal axis in a distance measured in the ground plane.

5. The autonomous mowing vehicle of claim 4, wherein the distance between the first axis and the longitudinal axis in the ground plane is at least 120mm.

6. The autonomous mowing vehicle of claim 4 or claim 5, wherein the roller is releasably attachable to the body in a plurality of positions such that the distance between the first axis and the longitudinal axis in the ground plane is adjustable.

7. The autonomous mowing vehicle of any preceding claim, wherein the outer edges of the wheel contact portions of the pair of wheels are separated by a distance Y, andwherein the length L is greater than the distance Y.

8. The autonomous mowing vehicle of any of claims 1 to 6, wherein the outer edges of the wheel contact portions of the pair of wheels are separated by a distance Y, andwherein the length L is less than the distance Y.

9. The autonomous mowing vehicle of claim 7 or claim 8, wherein the mower unit has a width W, wherein the width W is less than the distance Y.

10. The autonomous mowing vehicle of any preceding claim, wherein the roller contact portion comprises a plurality of roller contact portion segments.

11. The autonomous mowing vehicle of claim 10, wherein the roller contact portion comprises a plurality of roller contact portion segments, and each roller contact portion segment has substantially the same length.

12. The autonomous mowing vehicle of claim 10 or claim 11, wherein the roller contact portion segments are separated by 35mm or less.

13. The autonomous mowing vehicle of any preceding claim, wherein the first axis is equidistant from each of the wheels.

14. The autonomous mowing vehicle of any preceding claim, wherein the mower unit is connected to the body portion via an arm.

15. The autonomous mowing vehicle of claim 14, wherein the arm is configured such that the mower unit may be raised from a first mowing position to a second storage position.16.The autonomous mowing vehicle of any preceding claim, wherein the diameter of the roller is less than the diameter of a wheel of the pair of wheels.17.The autonomous mowing vehicle of any preceding claim, wherein the connection mechanism lies on a central plane of the body portion.

18. The autonomous mowing vehicle of any preceding claim, wherein the roller comprises one or more materials selected from a group of materials consisting of: steel, plastic and concrete.

19. The autonomous mowing vehicle of any preceding claim, wherein the roller comprises a cavity for receiving a ballast.

20. The autonomous mowing vehicle of any preceding claim further comprising an engine, wherein the engine is configured to power the autonomous mowing vehicle.

21. The autonomous mowing vehicle of claim 20 further comprising a drive system, wherein the drive system is configured to transfer power from the engine to the pair of wheels to propel the autonomous mowing vehicle.

22. The autonomous mowing vehicle of claim 21, further comprising a control system, wherein the control system is configured to operatively connect to the drive system for regulating the speed and direction of the autonomous mowing vehicle.

23. The autonomous mowing vehicle of any of claims 20-22, wherein the engine is an engine selected from a group of engines consisting of: petrol engines, diesel engines and electric engine.s

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