NL2015909B1 - Vehicle, system and method for displacing feed. - Google Patents

Abstract

A vehicle for displacing feed which is lying on a floor comprises a wheeled frame with a drive and control system for driving the vehicle over the floor, a rotatable annular part with an outer surface contacting the feed, a shaft around which the rotatable part is rotatable, and a tilt controller operatively connected to the drive and control system, and controlling the tilt of the shaft with respect to a vertical line, and at least one of a tilt detector providing a tilt related signal to the drive and control system, and a combination of a position determining device determining a position of the vehicle, and a memory with position dependent tilt related information, the combination retrieving a tilt related information based on the determined position, and providing a tilt related signal to the drive and control system based on the tilt related information, wherein the tilt controller controls the tilt of the axis based on the tilt related signal. This vehicle measures, knows or even predicts tilt on its route and can take action to prevent toppling over or otherwise counteract negative consequences of such tilting.

Description

Vehicle, system and method for displacing feed

The invention relates to a vehicle for displacing feed on a floor, and comprising a wheeled frame with a drive and control system for driving the vehicle over the floor, a rotatable annular part with an outer surface contacting the feed, and a shaft around which the rotatable part is rotatable.

Such vehicles are sold on the market, such as the Lely Juno® or the Hetwin Stallboy. The vehicles comprise an annular and rotatable cover, which is used a.o. to push feed toward a feed fence in a dairy stall. A problem of the known vehicles is that they often experience trouble when moving through hilly or sloping terrain.

It is an object of the present invention to improve the known vehicles, in particular to improve the moveability in such terrain or on slopes.

The invention achieves the object by means of a vehicle according to claim 1, in particular a vehicle for displacing feed on a floor, and comprising a wheeled frame with a drive and control system for driving the vehicle over the floor, a rotatable annular part with an outer surface contacting the feed, a shaft around which the rotatable part is rotatable, the vehicle further comprising a tilt controller operatively connected to the drive and control system, and controlling the tilt of the shaft with respect to the frame, and at least one of a tilt detector providing a tilt related signal to the drive and control system, and a combination of a position determining device determining a position of the vehicle, and a memory with position dependent tilt related information, the combination retrieving a tilt related information based on the determined position, and providing a tilt related signal to the drive and control system based on the tilt related information, wherein the tilt controller controls the tilt of the axis based on the tilt related signal.

By thus providing a tilt controller, that controls the tilt based on a tilt related signal, the vehicle can "know" or determine that it is on a slope and can expect negative consequences from that slope. Furthermore, based on this knowledge or determined signal, the tilt controller can now actively control the tilt of the axis, to counteract such negative consequences. In some cases, especially route related, the controller is even able to predict the presence of a slope, for example because the route leads to such a slope. Then the controller can even prevent the negative consequences from occurring, by taking preventive action.

An example of the negative consequences is a toppling over of the vehicle. Since the vehicle is used to push feed, it encounters a torque from the frictional forces of feed being pushed, and in some cases also from the floor. Under normal circumstances, the vehicle is balanced enough, and able to withstand this torque. On a slope, at least with at least a predetermined inclination, the combined torque of the frictional forces and gravity might topple over the vehicle. By changing the tilt, i.e. inclination of the shaft, this risk can be eliminated to a large extent. A less drastic consequence, but one that may be encountered more often, is the compromising of the function of the vehicle. In many cases, the vehicle is tilted such that the rotatable part touches the floor in one point, for optimum pushing of feed. This point will most often be in the front half of the vehicle, when driving, and more in particular in the most forward part of the annular part. On a sufficiently steep slope, gravity will tilt the vehicle with its annular part such that the point of touching the floor is no longer controlled and could come to lie for example at the back of the vehicle, where it no longer serves to push feed. Controlling the tilt of the shaft by the tilt controller may correct this, such that the vehicle will still work on slopes. Another problem possibly encountered is a ramp or other suddenly rather steep slope. The transition to this slope may be such that the vehicle is blocked, because the point of touch cannot make the transition, and/or frictional forces become too large. By controlling the tilt of the shaft the vehicle is then able to "lift its skirt" and continue travelling.

It should be noted that the term “point” does not mean that the annular part can only contact the floor and/or the feed lying thereon at a single point. In practice, this "point" will be a (small) part of the annular part, and the bottom edge thereof is often provided with a flexible strip, as a result of which the bottom edge is not only in contact with the floor and/or the feed lying thereon with the lowest point, but also with adjacent peripheral portions.

Although the vehicle may be used with different types of feed and with different types of floors, both indoors and outdoors, the vehicle according to the invention is in particular suitable for displacing and/or pushing feed which has been deposited along a feed fence on a floor of a feeding alley in an animal shed. The vehicle is self-propelled, driverless and autonomous. An electrical drive motor(s) or the like of the wheels are actuated by the control unit. The vehicle comprises a horizontal, central longitudinal axis. The vehicle has, for example, two separately driven rear wheels which are arranged on either side of said central longitudinal axis, and a front wheel which is situated substantially on the central longitudinal axis. Further embodiments of the invention will be described in the dependent claims, as well as in the description that follows below.

In embodiments, the tilt related signal comprises an inclination of the floor. Based thereon, the tilt controller may then determine whether or not to change the tilt of the shaft, and if yes, in what way. For example, the tilt related signal comprises an inclination angle value or percentage or the like, and the tilt controller compares this signal or value with a lower threshold for changing, or calculates the desired tilt change based on a predetermined algorithm that was stored in a memory of the vehicle. A simple example would be for the tilt controller to tilt the shaft in exactly the opposite direction and with an equal inclination, thus mimicking a horizontal floor surface to optimize the vehicle performance. However, it is noted that the tilt related signal may also comprise other information, such as quantitative or even qualitative instructions such as an instruction when to tilt and when not to. For example, the tilt related signal could comprise an instruction "tilt", i.e. into a predetermined tilt position, when the vehicle is present in a certain part of its environment, or on a certain part of its route, and so on. Other examples are easily envisaged.

In particular, the tilt detector comprises an inclinometer, an accelerometer and/or a gyroscope. These are useful tools in determining a quantitative value about the slope, and they may be selected from any known such tool. Alternative tools may also be provided on the vehicle, such as an optical 2D or 3D camera and coupled thereto image processing means. These also enable to determine a slope or other obstacle in front of the vehicle.

Additionally or alternatively, the position determining device is arranged to determine a relative or absolute position on a route preprogrammed into the memory. Herein, "preprogrammed" means that the route is at least partially determined before the control system instructs the vehicle to follow that route, even though the route may be changed during travelling, such as when an obstacle is encountered. By thus determining a position on the route, it is possible for the tilt controller to take into account information that was previously entered about the route, such as an inclination of certain parts of the route. In this way, it is possible for the vehicle to take into account inclinations et cetera without actually having to measure same. Herein, it is noted that the control system, being programmed for driving and in particular also navigating the vehicle, will often already comprise a counter of the path travelled or similar means for determining the point on the route. After all, it must be able to determine how to control the vehicle's wheel(s) and motor(s) to follow the route. Thus, the necessary means for this embodiment are often present already, which means there is no additional hardware required.

Additionally or alternatively, the position determining device is arranged to determine a position with respect to at least one reference position, such as a beacon or a gps satellite. Herein, a beacon can e.g. be strip in floor, a transmitter/transceiver in the environment and so on. Also, a set of beacons may be provided, wherein the control system is able, and arranged, to determine the position with triangulation or the like methods. It is also possible for the position determining device to determine the position with respect to gps satellites, which could also be called beacons. In any case, in these embodiments the vehicle is arranged to determine a relative position with respect to the beacon(s), which may sometimes be called an absolute position, such as if the beacons are gps satellites. in embodiments, the vehicle further comprises at least one shaft actuator for tilting the shaft with respect to the vehicle. This is a direct means for changing the tilt of the shaft. Herein, the actuator may change the tilt with respect to a vertical line, i.e. with respect to the direction of gravity. Alternatively or additionally, the actuator could also be arranged to rotate the shaft around a vertical axis, i.e. change its orientation without actually changing its absolute inclination with respect to the frame. Note that, in case the frame is tilted with respect to the vertical, i.e. is on a slope, such changed orientation will have the end effect of changing the inclination with respect to the vertical. Such a shaft actuator may comprise a shaft suspension with a hinge and a length controllable device to tilt the suspension with respect to the hinge, or any other tilter.

Other means to change the tilt of the shaft are also contemplated. In embodiments, the vehicle further comprises at least one vehicle actuator for tilting the vehicle with respect to the floor. With such a vehicle actuator, the whole frame can be tilted, and thus indirectly, the shaft is tilted as well. In this case, the rotatability of the shaft is not affected by an actuator directly working on the shaft. This may be advantageous with regard to wear of the shaft and any bearings, reliability of the functioning of the vehicle and so on. The vehicle actuator(s) may comprise a wheel suspension with a controllable cylinder or other length controllable device.

In embodiments, the vehicle further comprises an annular part rotator rotating the annular part. This annular part rotator ensures an active rotation of the annular part, and thus a more reliable feed pushing action. However, this is not necessary, since also frictional forces at a contact point between annular part and floor may be used to drive the annualr part and push the feed. The annular part rotator itself may comprise any type of motor, such as an electromotor.

As mentioned above, in some embodiments, the tilt controller tilts the shaft such that the annular part contacts the floor or feed thereon in a contact position. Then the driving force for rotating the annular part comes, partly or wholly, from friction between the annular part at the contact position and the feed or the floor, as is known from e.g. the lely Juno®. Note that the "contact point" may be somewhat above the floor, to prevent unnecessary wear if there is no feed on the floor. In particular embodiments, the tilt controller further controls a position of the contact position in dependence on the tilt related signal. In this embodiment, the tilt controller may change the tilt of the shaft and/or the tilt of the vehicle as a whole such that contact position is changed into a desired position. Such changed position may better suit the slope that the vehicle is on. For example, if the contact position is rather to the side of the vehicle, to have a good control of the direction of rotation of the annular part, and the tilt related signal indicates that the slope is not too steep, it may be advantageous to shift the contact point somewhat to the front of the vehicle, in the direction of travel, and thus slope upwards. However, other controls are possible.

In embodiments, the tilt controller controls the contact position to be shifted from a position in the front half of the vehicle, as seen with respect to a direction of movement over the floor, to a position in the back half of the vehicle, in dependence of the tilt related signal indicating that the vehicle climbs a ramp or is within a predetermined distance of a ramp to be climbed. In this embodiment, the vehicle, and in particular its annular part, is effectively prevented from colliding with a ramp. In effect, the annular part is lifted in the direction of travel, and thus may more easily overcome a transition to a ramp. Furthermore, the vehicle is now on the slope and thus in a tilted position, but the contact point and thus the support is shifted to the lower/lowest point of the vehicle. Thus, the contact point may now actively support and stabilise the vehicle while it is on the ramp. Although this might mean that its function of pushing feed may be compromised, it is expected that such ramp is often free of feed anyway. Note that a ramp is seldom provided at a feed fence, but rather at a corridor, gate or the like. Furthermore, when the vehicle is at the end of a slope and is about to (or has just started to) enter the horizontal part of the floor again, the tilting may again be adjusted to the new situation, such as by tilting back to the original position.

The invention will now be explained in more detail with reference to the attached figures, in which:

Fig. 1 and 2 diagrammatically shows a sideview of a vehicle according to the invention in a first, a second position, respectively, and

Fig. 3 diagrammatically shows another vehicle according to the invention.

Fig. 1 and 2 diagrammatically shows a sideview of a vehicle according to the invention in a first, a second position, respectively. The vehicle is generally denoted 1, and comprises a frame 2 with wheels 3, a shaft 4 rotatable around an axis 5 connected to an annular skirt 6 with a lowest point 7. The axis makes an angle a with the vertical 8 with respect to the ground 9. A drive and control system is generally denoted 10, and comprises or is connected to a position determining device 11 with an antenna 12 for picking up signals from beacons 13. Furthermore, a tilt controller is denoted 14.

The horizontal floor 9 connects to a ramp 15. An optional inclinometer is indicated by 16.

The vehicle 1 is e.g. used to push feed to a feed fence (not shown here), by means of a rotatable skirt 6. This skirt, or an annual part, is connected to a shaft 4, which can rotatate around its axis 5. This axis makes an angle a with respect to the vertical, and is thus tilted. This ensures that the skirt has a lowest point 7. This lowest point could touch the ground in order to drive the skirt 6 and rotate it, or be slightly above the ground 9, in order to be driven only by feed lying on the floor.

The vehicle 1 uses the drive and control system 10 to drive across the floor, such as in a dairy stall, e.g. according to a preprogrammed route, and in a direction of travel, generally indicated by arrow A. Thereto, the system 10 may comprise conventional software (and hardware) to control and drive the wheels 3, and to navigate. The latter may be embodied by means of counters that count rotations of the wheels 3, or also via external means, such as an on-board position determining device 11, that picks up signals from a beacon system 13 via an antenna 12. The beacon system 13 has been indicated very diagrammatically, and could be a locally installed beacon system, but also a gps system or the like (the beacons 13 then being gps satellites), to enable the determination of the position of the vehicle by means of triangulation.

Based on the determined position and or route, the vehicle 1, by means of its drive and control system 10 or position determining device 11, that may be a part thereof, may retrieve from a memory of the system an information about the tilt, slope or inclination of the floor. Based thereon, the vehicle 1 can determine if some action is required. In Figure 1, the vehicle is still on a horizontal floor 9, but will soon enter a ramp 15 which is at an angle β with the floor. This may lead to the skirt 6 bump into the ramp 15 with its lowest point 7. To prevent this, the vehicle 1 may control the tilt actuator 14 to tilt the shaft into a new position a', as shown in Figure 2. This may be an equal angle but then rotated about the vertical about 180° or the like, or may be a different angle altogether, for example depending on the angle β. In any case, the lowest point 7 has now been shifted from the front of the vehicle, with respect to the direction A, to the back of the vehicle 1, which can now enter the ramp 15 more or less freely.

Also shown is an inclinometer 16, that can directly determine the inclination of the floor. This is advantageous, in that the position determination may not always be very accurate, or the information about position dependent inclination is not up to date. On the other hand, based on the tilt information from the inclinometer 16, the vehicle 1 is only able to respond to an actual change, without predicting a tilt change, so that preventive action is not well possible.

Fig. 3 diagrammatically shows another vehicle according to the invention. This vehicle is denoted T, but all (other) parts that correspond to those in Figures 1 and 2 are denoted by the same reference numerals. Furthermore, 17 generally denotes a camera system, 18 denotes vehicle actuators, and 19 denotes a skirt rotator.

The vehicle T is a vehicle in which the skirt 6 is actively rotated around the shaft 4 by means of a skirt rotator 19, such as any electromotor or the like. Even though such a vehicle T would not seem to need a lowest point 7 contacting the floor surface, when driving up a ramp 15, it may be advantageous to provide a support to the vehicle T. Thereto, the drive and control system 10 may control the vehicle actuators 18 to tilt the vehicle T as a whole. The vehicle actuators 18 may comprise e.g. controllable cylinders or the like, that can be extended differently, thus causing a tilt. Herein, the drive and control system 10 acts as a tilt controller. During climbing of the ramp 15 by the vehicle T, the now lowest point 7 may serve as a support for the vehicle, when going down, the lowest point 7 may be provided in front, i.e. in the direction of travel, and when the vehicle is on a horizontal surface again, the vehicle actuators may remove any tilt of the vehicle 1'.

The drive and control system 10 (or a separate tilt controller) may act based on information from an inclinometer 16, route information gathered by the system 10 itself, or e.g. also on the basis of information gathered via the camera system 17, which may comprise a 3D camera, one or more 2D cameras and so on. The images collected are assessed by the camera system and converted to tilt information, that is supplied to the drive and control system 10 (or a separate tilt controller), to control the vehicle actuators 18.

The invention is not limited to the embodiments illustrated in the figures. The person skilled in the art may perform various changes and modifications which are within the scope of the invention. Furthermore, the above-described properties may be applied, both separately and in any desired combination, in the vehicle, the system or the method according to one or more of the claims.

Claims (10)

A vehicle for delivering feed on a floor, and comprising: A wheeled vehicle with a drive and control system for driving the vehicle over the floor, - A rotatable annular part with an outer surface that comes into contact with the feed, - An axle around which the rotatable part is rotatable, the vehicle further comprising: - A tilt control operatively connected to the drive and control system, and controlling the tilt of the axle relative to the frame, and - at least one of - A tilt detector which provides a tilt-related signal to the drive and control system, and - A combination of a position-determining device which determines a position of the vehicle, and a memory with position-dependent tilt-related information, wherein the combination retrieves a tilt-related information based on the determined position, and a tilt-related signal provided to the drive and control system on basi s of the tilt-related information, wherein the tilt control controls the tilt of the axis based on the tilt-related signal. A vehicle according to claim, wherein the tilt-related signal comprises a slope of the floor. Vehicle according to one of the preceding claims, wherein the tilt detector comprises an inclinometer, an accerolometer and / or a gyroscope. A vehicle according to any preceding claim, wherein the position determining device is arranged to determine a relative or absolute position on a route pre-programmed in the memory. A vehicle according to any preceding claim, wherein the position determining device is arranged to determine a position relative to at least one reference position, such as a beacon or a GPS satellite. A vehicle according to any preceding claim, further comprising at least one axle actuator for tilting the axle relative to the vehicle. A vehicle according to any preceding claim, further comprising at least one vehicle actuator for tilting the vehicle relative to the floor. A vehicle according to any preceding claim, further comprising an annular part rotator that rotates the annular part. A vehicle according to any preceding claim, wherein the tilt control tilts the axle such that the annular part touches the floor in a touch position, the tilt control further controlling a position of the touch position in dependence on the tilt-related signal. The vehicle of claim 9, wherein the tilt control controls the tangent position to be moved from a position in the front half of the vehicle, as viewed with respect to a direction of movement across the floor, to a position in the rear half of the vehicle, depending on whether the tilt signal indicates that the vehicle is climbing a slope or is within a predetermined distance of a slope to be climbed.