WO2018015744A1

WO2018015744A1 - Single rail robot

Info

Publication number: WO2018015744A1
Application number: PCT/GB2017/052117
Authority: WO
Inventors: Pål Johan FROM; Lars GRIMSTAD
Original assignee: Norwegian University Of Life Sciences; RAMSAY, Laura Anne
Priority date: 2016-07-19
Filing date: 2017-07-18
Publication date: 2018-01-25
Also published as: GB201612519D0; GB2552341A

Abstract

A device comprising: a first and a second independently driven cart (200, 300) slidably attached to a rail (100) for translation along the rail (100); a platform (400) connected to the first cart (200) via at least a first connecting rod (510a, 510c) and to the second cart (300) via at least a second connecting rod (510e, 510f), wherein translation of the first and/or second cart (200, 300) along the rail (100) provides motion in an x and/or a z direction to the platform (400), the x direction being parallel with the direction of translation of the first and/or second cart (200, 300) along the rail (100) and the z direction being perpendicular to the x direction; and an independently driven actuator (220) connected to the first connecting rod (510a) to move the first connecting rod (510a) relative to the rail (100) so as to move the platform (400) in a y direction that is perpendicular to the x and the z directions.

Description

Single Rail Robot

Technical Field

The present disclosure relates to a rail-based robot or robotic manipulator. More specifically, but not exclusively, the present disclosure relates to a single-rail-based robot having three degrees of freedom coincident with an x, y, and z axis.

Background

Rail-based robots are often used for pick-and-place work (e.g. for sorting objects), assembly operations (e.g. circuit board assembly), machining (e.g. welding, drilling, and cutting), and sensing applications (e.g. mapping the topology of a surface).

Typically, a single-rail-based robot, such as a single-rail parallel robot, comprises two independently slidable carts on a single rail, and a platform attached to each of the two carts via connecting rods or links. The connecting rods or links may be stiff or flexible. Such robots provide two perpendicular degrees of motion to the platform for applications that only require movement in two dimensions. For example, such robots provide linear movement to the platform in an x direction parallel with the rail by translating the two carts by the same amount in the same direction along the rail. Further, such robots provide transverse movement to the platform in a z direction perpendicular to the x direction by translating the two carts along the rail towards each other or away from each other. Movement of the platform in the z direction only will of course be understood to define a path that is perpendicular to the length of the rail.

It will be appreciated that in such arrangements the two carts may move along the rail in the same direction with the same velocity to generate motion of the platform in the x direction only. Further, in such arrangements the two carts may move in opposite directions with the same velocity to generate motion of the platform in the z direction only. In addition, in such arrangement the two carts may move in the same or opposite direction with different velocities to generate motion to the platform in the x and z directions.

To provide a third degree of motion to the platform in a y direction perpendicular to the x and the z direction, current single-rail-based robots typically require at least one additional rail and/or one or more additional carts. These additional components cause issues with the overall size, the cost, and the manufacturing and operational complexity of the robot.

For example, owing to the need to add one or more additional rails to a single-rail- based robot to move the platform in three orthogonal directions, the size of the robot is often larger than the workspace over which movement of the platform may extend in the x, y, and z directions. Consequently, it is difficult to arrange such robots close together in an array, particularly when the workspace (the space over which movement of the platform may extend) of each robot needs to overlap with the workspace of its neighbouring robots, as is typically required for pick-and-place, assembly, and other such applications.

Furthermore, even when it is possible to arrange the robots together in an array with overlapping workspaces, the additional space occupied by the additional rail(s) often requires the workspace of each robot to be reduced in order to prevent collisions with the additional rail(s).

It has also been proposed to add a further cart to the single rail to move the platform in three orthogonal directions. However this also reduces the workspace of a robot since the additional cart(s) limits the range of movement of the other carts on the single rail. That is, the carts are often not able to translate along the length of the rail without one or more of the additional carts getting in the way. This therefore limits the range of motion provided by each cart to the platform and requires complex coordinated movement between the carts to move the platform in three orthogonal directions.

An object of the invention is to provide an improved single-rail-based robot device, system, and method for providing motion in three perpendicular directions. Summary

From a first aspect, the invention provides a device comprising: a first and a second independently driven cart slidably attached to a rail for translation along the rail; a platform connected to the first cart via at least a first connecting rod and to the second cart via at least a second connecting rod, wherein translation of the first and/or second cart along the rail provides motion in an x and/or a z direction to the platform, the x direction being parallel with the direction of translation of the first and/or second cart along the rail and the z direction being perpendicular to the x direction; and an independently driven actuator connected to the first connecting rod to move the first connecting rod relative to the rail so as to move the platform in a y direction that is perpendicular to the x and the z directions.

The first and second independently driven carts may be independently translated linearly back and forth along the rail in the x direction. That is, the independently driven carts may be translated along a single axis parallel with the rail.

The movement of the first and second independently driven carts may be transferred to the platform via the first and the second connection rods, respectively. That is, the linear translation of the two independently driven carts along the rail (i.e. along the x-axis) may move the first and/or the second connecting rod relative to the rail so as to advantageously move the platform in one or two perpendicular degrees of motion (i.e. to move the platform in the x direction or the z direction). Specifically, the linear translation of the two independently driven carriages along the rail may provide motion to the platform in the x direction by translating the first and the second independently driven carts (and therefore also the first and the second connecting rod) in the same direction along the rail. In addition, the linear translation of the first and/or the second independently driven carts along the rail (i.e. along the x-axis) may provide motion to the platform in the z direction (i.e. motion in along a z-axis orthogonal to the x-axis) by translating the first and/or the second independently driven carts (and therefore also the first and the second connecting rod) closer together or further away from each other along the rail.

It will of course be appreciated that the first and the second independently driven carts may be translated in the same direction along the rail at different relative speeds to move the two carts closer together or further away from each other. In this way, the linear translation of the first and the second independently driven carts along a single axis (i.e. the x-axis) may simultaneous provide motion to the platform in the x direction and the z direction.

It will also be appreciated by those skilled in the art that the independently driven actuator connected to the first connecting rod provides a third degree of motion (i.e. motion in the y direction) to the platform by moving the first connecting rod relative to the rail so as to move the platform in a y direction. In this way, the device having two independently slidable carts on a single rail is able to move the platform in the x, y and z directions without requiring an additional rail or an additional cart.

Advantageously, therefore, the device provides motion in three perpendicular directions in a more compact form than current single-rail-based robots. This allows the device to be arranged more closely together with other such devices in an array. Further, since the size of the device is not made to exceed or become substantially comparable to its workspace by the addition of one or more rails, it is possible and/or easier to overlap the workspace of a robot with the workspace of an adjacent robot in the array. In addition, the workspace of each robot in the array does not need to be restricted in order to avoid collisions with an additional rail. In one example application such a device may find particular use as a precision planting/weeding tool for accurate placement of plants/seeds or removing weeds in agricultural applications.

Further advantageously, by using an independently driven actuator connected to the first connecting rod to provide a third degree of motion to the platform, the range of motion provided to the platform by the first and/or the second independently driven cart is not restricted by the addition of one or more additional carts. In this way, the device also provides simpler coordinated movement between the carts for moving the platform in the x and/or y directions than rail-based robot devices having more than two carts on a rail.

Another advantage of such a device is that the size of the workspace along the x-axis is limited only by the length of the rail. In this way, the workspace along the x-axis may be set to any size by using a suitably long rail.

The platform may be positioned level with the rail (i.e. parallel with the x-axis).

The actuator may be positioned on the first cart or on the platform. In the former arrangement it will be appreciated that, in addition to movement in the x and the z directions, the first cart may provide motion to the platform in the y-direction. Further, positioning the actuator on existing components of a single-rail-based robot device saves space.

In some embodiments, the actuator may be connected to the first connecting rod via a lever that extends away from the actuator. Movement of the actuator may move the lever to move the first connecting rod relative to the rail so as to move the platform in a y direction. The lever provides additional leverage for moving the platform in the y direction with the actuator. In this way it is easier for the actuator to move the platform in the y direction.

The first connecting rod and the actuator may be connected to separate ends of the lever to provide maximum leverage for moving the platform in the y direction with the actuator.

The first connecting rod may be connected to the lever via a ball joint or other rotational joint. The ball joint enables the first connecting rod to be moved by the lever and the first cart over a wider range of angles in the x, y, and/or z directions, thereby providing a greater range of motion for the platform to be moved by the first connecting rod in all three directions (i.e. x, y, and z).

The actuator may be connected to one end of the first connecting rod. Specifically, the actuator may be directly connected to one end of the first connecting rod. In some embodiments, the lever may be directly connected to one end of the first connecting rod.

The first connecting rod may be connected to the first cart, the actuator, and/or the platform via a ball joint or other rotational joint. It will be appreciated that the ball joint or other rotational joint will enable the first connecting rod to be moved over a wider range of angles in the x, y, and/or z directions, thereby providing a greater range of motion for the platform to be moved by the first connecting rod in all three directions (i.e. x, y, and z).

The actuator may be a rotating actuator or a linear actuator.

The linear actuator may translate along a single axis extending at least partially in the y direction so as to move the first connecting rod relative to the rail and thereby move the platform at least partially in the y direction.

The rotating actuator provides motion of the platform in a least two directions by, for example, rotating the first connecting rod relative to the rail in a plane that extends in the y direction and the z direction. Optionally, the plane may also extend in the x direction. The first connecting rod may transfer its rotation to the platform such that the platform also rotates relative to the rail in a plane that extends in the y direction, the z direction and, optionally, the x direction. For example, the first connecting may be rotated by the rotating actuator such that the platform moves along an arc or arc-like trajectory relative to the rail in a plane that extends in the y direction, the z direction and, optionally, the x direction.

Preferably, the platform moves in the same plane as the first connecting rod. The path of the platform may define a circle, an ellipsoid, an arc, or a polynomial shape. In this way, the rotating actuator may provide motion in the z direction and/or x direction to the platform, in addition to the x direction and z direction motion provided by the movement of the first and/or the second cart. Accordingly, the rotating actuator provides additional fine or coarse control to move the platform in the z and/or x direction.

Accordingly, it will be appreciated that the movement of the actuator may be in a plane that is inclined relative to a plane parallel with the x and y directions. Preferably, the actuator moves in a plane perpendicular to the x direction (i.e. in a plane extending parallel with the y axis and the z axis). Preferably, the actuator moves the first connecting rod and/or the platform in a plane perpendicular to the x direction (i.e. in a plane extending parallel with the y axis and the z axis).

In some embodiments, the actuator may be driven by a motor, a magnetic field, an electric current, or even a change in temperature, pressure or humidity. For example, movement of the actuator may be magnetically or electrically activated. As another example, the movement of the actuator may be activated by a change in temperature, pressure, or humidity.

Optionally, the actuator may comprise a motor, preferably an electric motor.

Optionally, the actuator may be attached to a flange. The flange may be connected to the platform or the first cart.

Optionally the first and the second cart may be controlled using a first controller for moving the platform in the x and/or the y direction. Additionally, the actuator may be controlled using the first controller, or a second controller in communication with the first controller, for moving the platform in one or more of the three dimensions.

The second connecting rod may be directly connected onto the second cart and onto the platform. That is, unlike the first connecting rod, the second connecting rod may not be connected to an actuator arranged to move the platform in the y direction. However, in some embodiments the second connecting rod may be moved relative to the rail by a further actuator so as to assist movement of the platform in the y direction.

The first connecting rod may be connected with a side of the platform that extends in a direction between a first end of the platform that faces the first cart and a second end of the platform that faces the second cart. Connecting the first connecting rod to a side of the platform in this way provides better leverage for the platform to be moved by the first connecting rod.

In some embodiments, additional connecting rods may connect the first and/or the second cart to the platform. In some examples, the number of additional connecting rods may depend on the type of joint (e.g. ball joint or other rotational joint) used to connect the connecting rods to the platform and/or the cart. Additionally or alternatively, additional connecting rods may be used to connect the first and/or the second cart to the platform to restrict the rotation of the platform (when, for example, an external force(s) such as the force from a gust of wind acts on the platform). The number of additional rods may vary according to the extent to which the rotation of the platform needs to be restricted.

Thus in some embodiments, the device further comprises a third and a fourth connecting rod connecting the platform to the first cart, wherein the third and the fourth connecting rods are parallel with each other and attached to the first end of the platform. These additional connecting rods prevent the platform from twisting or rotating around certain axes such as in the plane of the platform when, for example, an external force(s) acts on the platform as described above. That is, this arrangement of the first, third, and fourth connecting rods helps to keep the plane of the platform level when external force(s) act on the platform.

The second connecting rod may be in connection with the second end of the platform.

In a set of embodiments, the one or more of the connecting rods may be connected to the platform and the first or second cart via ball joints or other types of rotational joints. The ball joints enable the connecting rods to be moved over a wider range of angles in the x, y and/or z directions, thereby providing a greater range of motion for the platform to be moved.

The device may also comprise a fifth and a sixth connecting rod connecting the platform to the second cart, wherein the fifth and sixth connecting rods are parallel with the second connecting rod, and the fifth connecting rod is attached to the second end of the platform, and the sixth connecting rod is attached to the platform between the second and fifth connecting rods and away from the second end of the platform such that the points of connection of the second and the sixth connecting rod define a parallelogram. This arrangement is particularly convenient if ball joints are used. It may be viable to use fewer rods if other types of joint are used.

Defining a parallelogram shape with the second, fifth, and sixth connecting rods in this way further prevents undesirable twisting and/or rotation of the platform. That is, for example, the parallelogram configuration also (i.e. in addition to the arrangement of the third and fourth connection rods) helps to keep the plane of the platform level with the rail when external forces act on the platform or when the cart(s) translate along the rail and/or as the actuator moves the platform in the y direction.

The Applicant has recognised that a device according to various embodiments of the present invention, and the associated benefits, may be particularly applicable to a robot used for precision weeding or pick-and-piace operations. Thus in various examples the platform preferably carries a weeding tool, it is often desirable to arrange a plurality of weeding tools adjacent to one another in an array.

The applicant has also realised that a device according to various embodiments of the present invention, and the associated benefits, may be particularly applicable to a robot used for pick-and-place operations or other such operations where a workspace extending along the x, y, and the z axis is required and/or where a very large workspace extending in one direction (e.g. the x direction) is needed.

From a second aspect, the invention provides a system comprising a plurality of the devices described herein and the plurality of devices may be arranged adjacent to each other in an array. Preferably the rail of each device is such an array is arranged parallel and level with the rail(s) of other devices in the array.

The plurality of devices may be arranged adjacent to each other such that a workspace over which the platform of at least one device in the array may move at least partially overlaps with a workspace over which the platform of a neighbouring device may move, the neighbouring device being adjacent to the at least one device. Overlapping the workspaces in this way provides greater flexibility of pick-and-place and assembly applications. In addition, it provides greater robustness against devices failures. For example, if one device in the array fails, one or more neighbouring robots may function in the workspace of the failed device to complete a task.

The array may be a one dimensional array, a two dimensional array, or a three dimensional array.

From a third aspect, the invention provides a method for moving a platform connected to (i) a first cart via at least a first connecting rod and to a second cart via at least a second connecting rod, the first and second carts being independently driven and slidably attached to a rail for translation along the rail, the method comprising: translating the first and/or the second cart along the rail to provide motion to the platform in a x and/or a z direction to the platform, the x direction being parallel with the direction of translation of the first and/or second cart along the rail and the z direction being perpendicular to the x direction; and driving an actuator connected to the first connecting rod to move the first connecting rod relative to the rail so as to move the platform in a y direction that is perpendicular to the x and the z directions.

The actuator may be connected to the first connecting rod via a lever that extends away from the actuator, and the method may further comprise driving the actuator to move the lever so as to move the first connecting rod relative to the rail and thereby move the platform in the y direction.

The method may further comprise picking and placing a plant/seed with a planting tool attached to the platform, or weeding with a weeding tool attached to the platform.

Brief description of drawings

One or more non-limiting examples will now be described, with reference to the accompanying drawings, in which:

Figure 1 is a front perspective view of a singie-rail-based positioning device in accordance with an example of the present invention; Figure 2 is a magnified view of a first cart of the single-rail-based positioning device of Figure 1 ;

Figure 3 is a magnified view of a second cart of the sing!e-rail-based positioning device of Figure 1 ;

Figure 4 is a rear perspective view of the single-rail-based positioning device of Figure 1 ;

Figures 5a to 5f show side views of the single-rail-based positioning device at different positions; and

Figures 6a to 6f respectively show corresponding front views of the single-rail-based positioning device illustrated in Figures 5a to 5f.

Referring to the figures of the accompanying drawings, a single-rail-based positioning device 10 is illustrated. The single-rail-based positioning device 10 comprises a rail 100 mounted horizontally with respect to the ground upon which a first and a second cart 200, 300 independently slide along in an x direction that is parallel with an x-axis 500x. The rail 00 extends from a mounting surface 105a of a support frame 105 with its height perpendicular to the mounting surface 105a. In this example, and as best seen in Figures 5a-5d and 6a-6d, the x-axis 500x is parallel with the length of the rail 100 (i.e. parallel with the longest dimension of the rail 00) and perpendicular to a y-axis 500y and a z-axis 500z. The y-axis 500y is parallel with the height of the rail 00 and perpendicular to the x-axis 500x and the z-axis 500z. The z-axis 500z is parallel with the mounting surface 105a of the support frame 105 and perpendicular to the x-axis 500x, y-axis 500y, and the height of the rail 100.

The single-rail-based positioning device 10 also comprises a platform 400 and connecting rods 510a - 51 Of linking the platform 400 to the two carts 200, 300. Each cart 200, 300 comprises a rail mount 205, 305 shaped to slidabiy engage with the rail 100. Each cart 200, 300 also comprises a mounting bracket 250, 350 having a base 250a, 350a for holding an actuator 2 0, 310. In this example, the base 250a, 350a of each cart 200, 300 holds a motorised pinion gear 210, 310 that slides the cart 200, 300 along the rail 100.

To slide the cart 200, 300 along the rail 100, the motorised pinion gear 210, 310 rotates a circular gear 215, 315 (also referred to herein as a pinion gear 215, 315) that engages with teeth on a guide rack 1 10, The guide track 110 is placed parallel with the length of the rail 100 (i.e. parallel with the x-axis 500x) on the support frame 105. Rotational motion applied to the circular gear 2 5, 315 causes the cart 200, 300 to move along the rail 00 (i.e. along the x-axis 500x), thereby translating the rotational motion of the circular gear 215, 315 into linear motion.

The mounting bracket 250, 350 of each cart 200, 300 also comprises a first flange 250b, 350b. The first flange 250b, 350b extends outwardly away from the rail 100 and the base 250a, 350a, and may hold an actuator 220. In this example, only the first flange 250b of the first cart 200 holds a rotating actuator 220 and the rotating actuator 220 is positioned on the first flange 250b so as to rotate a lever 230 in a plane orthogonal to the x-axis 500x and z-axis 500y plane (i.e. orthogonal to the x-axis 500x and parallel with the y-axis 500y and z-axis 5Q0z). However, in other examples, the rotating actuator 220 may of course be positioned on the first flange 250b so as to rotate a lever 230 in a plane that extends along the X-, y~, and z~ axis 500x, 500y, 500z (i.e. to rotate a lever 230 in a plane that is not orthogonal to the x-axis 500x and z-axis 500y plane).

The lever 230 is connected to the platform 400 via a first connecting rod 510a. The first connecting rod 510a transfers motion of the lever 230 to the platform 400 such that the platform 400 rotates together with, and in the same plane as, the lever 230. The motion of the platform 400 by the lever 230 defines an arc that extends along the z-axis 500z and the y-axis 500y.

The lever 230 is joined onto the rotating actuator 230 using a fastener and onto the first connecting rod 510a using a ball joint 502a. To provide maximum leverage with the lever 230 for moving the platform 400, the first connecting rod 510a is connected to an end of the lever 230 that extends away from the joint connecting the lever 230 to the rotating actuator 220.

The first connecting rod 510a is connected to a side flange 430a of the platform 400 using a ball joint 502a. The side flange 430a of the platform 400 is positioned on a first side 430 of the platform 400. In this example, the first side 430 of the platform 400 is the side of the platform 400 that is closest to the rail 00, and is located between a first end 410 of the platform 400 that faces the first cart 200 and a second end 420 of the platform 400 that faces the second cart 300. However, the side flange 430a may of course be located on a side of the platform 400 that opposes the first side 430 of the platform 400, such as second side 440 shown in Figure 1. Preferably, the side flange 430a extends from the platform 400 such that the ball joint 502a attached thereto to at least partially faces the first cart 200.

In addition to the first flange 250b, 350b, the mounting bracket 250, 350 of each cart 200, 300 also comprises a second flange 250c, 350c for connecting the cart 200, 300 to the platform 400 via connecting rods 510b-510f. The second flange 250c, 350c extends outwardly away from the rail 100 and the base 250a, and is angled on the mounting bracket 250, 350 to face the platform 400, as best seen in Figures 1 , 5a-5d, and 8a-6d.

In this example, a second 510b and a third connecting rod 510c connects the second flange 250c of the first cart 200 to a first flange 410a of the platform 400. In addition, a fourth 510d, a fifth 510e, and a sixth connecting rod 51 Of connects the second flange 350c of the second cart 300 to a second flange 420a of the platform 400. The second 510b to sixth 51 Of connecting rods are connected to their respective cart flanges 250c, 350c and to their respective platform flanges 410a, 420a via bail joints 502b'-502f , 502b-502f. The bail joints 502b'-502f , 5Q2b-502f allow the connection rods to swivel in three dimensions so as to allow the platform 400 to move relative to the rail 100 along the x-axis 500x, y-axis 500y, and z- axis 500z.

The first flange 410a of the platform 400 extends from the first end 410 of the platform 400 to face the second flange 250c of the first cart 200. The second flange 420a of the platform 400 extends from the second end 420 of the platform 400 to face the second flange 350c of the second cart 300. Optionally, the first flange 410a of the platform 400 is parallel with the second flange 250c of the first cart 200. Further optionally, the second flange 420a of the platform 400 is parallel with the second flange 350c of the second cart 300.

As best seen in Figures 2, 4 and 5a-5d, the second 510b and third 510c connecting rods are connected to their respective cart flange 250c and to their respective platform flange 4 0a such that they are parallel with each other. The bail joints 502b, 502c connecting the second 510b and third connecting rods 510c to the first flange 410a of the platform 400 line up parallel with the y-axis 500y. Furthermore, the bail joints 502b^!, 502c' connecting the second 510b and third connecting rods 510c to the second flange 250c of the first cart 200 line up parallel with the y-axis 500y. Of course the ball joints of the second 510b and the third 510c connecting rods may be arranged differently on the second flange 250c of the first cart 200 and on the first flange 4 0a of the platform 400. Other types of joints and configurations can also be used

As best seen in Figure 1 , 3, and 6a-8d, the fourth 51 Od, fifth 51 Oe and sixth 51 Of connecting rods are also connected to their respective cart flange 350c and to their respective platform flange 420a such that they are parallel with each other. The bail joints 502d, 502e connecting the fourth 51 Od and fifth 51 Oe connecting rods to the second flange 420a of the platform 400 line up parallel with the y-axis 500y. The ball joints 502d', 502e' connecting the fourth 51 Od and fifth 51 Oe connecting rods to the second flange 350c of the second cart 300 also line up parallel with the y-axis 500y.

Further, the ball joint 502f connecting the sixth connecting rod 51 Of to the second flange 420a of the platform 400 forms a triangle with the bail joints 502d, 502e connecting the fourth 510d and fifth 510e connecting rods to the second flange 420a of the platform 400. That is, in the y-axis 500y, bail joint 502f is placed on the second flange 420a of the platform 400 in between ball joints 502d and 502e, and in the x-axis 500x, ball joint 502f is placed on the second flange 420a of the platform 400 away from ball joints 502d and 502e.

The ball joint 502f connecting the sixth connecting rod 51 Of to the second flange 350c of the second cart 300 forms a triangle with the bail joints 502d', 502e' connecting the fourth 51 Od and fifth 51 Oe connecting rods to the second flange 350c of the second cart 300. That is, in the y-axis 500y, ball joint 502f is placed on the second flange 350c of the second cart 300 in between ball joints 502d' and 502e', and in the x-axis 500x, ball joint 502f is placed on the second flange 350c of the second cart 300 away from ball joints 502d' and 502e\ Preferably, ball joint 502f forms an isosceles triangle or equilateral triangle with ball joints 502d' and 502e' on the surface of the surface of the second flange 350c of the second cart 300.

Accordingly, as best seen in Figure 1 and 3, the ball joints 502e, 502f, 502f , 502e' of the fifth 51 Oe and sixth 51 Of connection rods define a parallelogram shape. Similarly, the ball joints 502d, 502f, 502f , 502d^! of the fourth 51 Od and sixth 51 Of connection rods also define a parallelogram shape.

The arrangement of the first, second, third, fourth, fifth, and sixth connecting rods 510a-51Qf, prevents undesirable twisting and/or rotating forces in the plane of the platform 400 when, for example, an external force is applied to the platform and/or when the first cart 200, the second cart 300, or the rotating actuator 250 moves the platform 400. Specifically, the arrangement of (i) the second 510b and third 510c connecting rods parallel to each other on the first flange 410a at the first side 410 of the platform 400, (ii) the first connecting rod 510a on the side flange 430a at the first side 430 of the platform 400, and (iii) the fifth 51 Oe and sixth 51 Of connecting rods defining a parallelogram shape prevents undesirable twisting and/or rotating forces in the plane of the platform 400That is, the parallelogram configuration keeps the plane of the platform 400 level. .

As seen in Figures 1 and 4, the power and control connection to the motorised pinion gear 210 and to the rotating actuator 250 on the first cart 200 is made by cable carrier 30. The power and control connection to the motorised pinion gear 310 on the second cart 300 is made by cable carrier 120. The cable carriers are supported on the support frame 105 by a shelf 1 11 extending from the support frame 105, and attached to the carts by brackets 280, 370. The cable carriers 120, 130 allow the carts to move along the rail 100 without tangling or breaking the power and control connection wires.

Figure 5a to 5d and 6a to 6d illustrate the movement of the platform 400 in three dimensions (i.e. along the x-axis 500x, y-axis 500y, and z-axis 500z) in accordance with the present disclosure.

During operation, the platform 400 may be moved along the x-axis 500x by moving the first and second cart 200, 300 in the same direction along the rail 100 (i.e. along the x- axis 500x). The movement of the carts 200, 300 is transferred to the platform 400 via the connection rods 510a-510f. Moving the carts 200, 300 to the right hand side of the rail 100 in Figures 6a to 6d moves the platform 400 in a positive x-direction along the x-axis 500x. Moving the carts 200, 300 to the left hand side of the rail 100 in Figures 6a to 6d moves the platform 400 in a negative x-direction along the x-axis 500x.

The platform 400 may separately or additionally be moved along the z-axis 500z by moving the first and second cart 200, 300 closer together or further away from each other along the rail 00. Moving the carts 200, 300 closer together moves the platform 400 towards the bottom of the page (i.e. away from the rail 100) along the z-axis 500z in Figures 5a to 5d and 6a to 6d. Moving the carts 200, 300 away each other moves the platform 400 towards the top of the page (i.e. towards the rail 100) along the z-axis 500z in Figures 5a to 5d and 6a to 6d. Movement towards the top of the page in Figures 5a to 5d and 6a to 6d defines a positive z-direction along the z-axis 500z. Movement towards the bottom of the page in Figures 5a to 5d and 6a to 6d defines a negative z-direction along the z-axis 500z.

The platform 400 may also separately, or in addition to the movement provided by the carts 200, 300, be moved along the y-axis 500y by rotating the rotating actuator 220 attached to the first cart 200. As set out above, to move the platform 400 along the y-axis 500y, the rotating actuator 220 rotates a lever 230 in a plane orthogonal to the x-axis 500x and z-axis 500y plane. The rotational movement of the lever 230 is transferred to the platform 400 via the first connecting rod 510a such that the platform 400 moves in the same plane as the lever 230. The path along which the platform 400 moves defines an arc that extends along the z- axis 500z and the y-axis 500y.

In Figures 5a to 5d, rotating the rotating actuator 220 in a clockwise direction moves the platform 400 towards the left side of the page. Movement towards the left side of the page in Figures 5a to 5d defines a negative y-direction along the y-axis 500y. Rotating the lever 230 in an anti-clockwise direction moves the platform 400 towards the right side of the page. Movement towards the right side of the page in Figures 5a to 5d defines a positive y- direction along the y-axis 500y.

Since the rotating actuator 220 rotates the platform 400 along an arc that extends along the z-axis 500z in addition to the y-axis 500y, the clockwise rotation or the

anticlockwise rotation of the rotating actuator 220 in Figures 5a to 5d may also move the platform 400 in the positive z-direction or the negative z-direction.

In Figure 5a and 8a, the platform 400 is shown in a starting position located on a right side of the support frame 105.

Figures 5b-5d and 6b-6d illustrate the movement of the platform 400 relative to a starting position of the platform 400 illustrated in Figures 5a and 6a.

In a first step, starting from the starting position of the platform 400, the rotating actuator 220 is rotated clockwise such that the platform 400 is moved in the negative y- direction and the positive z-direction to the first position shown in Figures 5b and 6b. The first position of the platform 400 is located on a left side of the support frame 105 and closer to the rail 100 compared to the starting position of the platform 400. The location of the first position of the platform 400 along the x-axis 500x is the same as the starting position of the platform 400.

In a second step, the first cart 200, the second cart 300 and the rotating actuator are moved such that the platform is moved from its first position to the second position shown in Figures 5c and 6c. Specifically, the first cart 200 and the second cart 300 are moved towards each other along the rail 100 such that the platform 400 is lowered in the negative z- direction, and the rotating actuator 220 is rotated anti-clockwise such that the platform 400 is moved in the positive y-direction and further lowered the negative z-direction. The second position of the platform 400 is located substantially directly underneath the support frame 105 and further away from the rail 100 compared to the starting position of the platform 400 and the first position of the platform 400. The location of the second position of the platform 400 along the x-axis 500x is the same as the first position of the platform 400 and the starting position of the platform 400.

In a third step, the first cart 200 and the second cart 300 are moved in the positive x- direction at substantially the same speed along the rail 100 such that the platform 400 is moved from the second position to the third position shown in Figures 5d and 5d. The third position of the platform 400 is located further towards the right side of the rail 100 than the starting, first, and second position of the platform 400. The location of the third position of the platform 400 along the x-axis 500x and the y-axis 500y is the same as the second position of the platform 400.

It will be appreciated that the range of motion of the platform 400 as it is moved along the x-axis 500x is determined by the movement of the first cart 200 and the second cart 300 along the rail 100. It will also be appreciated that the range of motion of the platform 400 as it is moved along the z-axis 500x is determined by the movement of the first cart 200 and the second cart 300 along the rail 100 and the rotation of the rotating actuator 220 attached to the first cart 200. It will also be appreciated that the range of motion of the platform 400 as it is moved along the y-axis 500x is determined by the rotation of the rotating actuator 220. The rail 00 may be mounted onto the support frame 105 using a fastening device such as an adhesive layer or a bolt. Optionally, the rail may comprise openings for receiving a fastening device e.g. for receiving a bolt.

Rail 100 may be any suitable rail upon which the carts 200 and 300 can move along such as, for example, a bearing rail 100 or a dovetail rail 100. The rail 100 may loosely and at least partially slot into a portion of each rail mount 205, 305 for smooth sliding of the carts 200, 300 along the rail 100. For example, the rail 100 (e.g. dovetail rail 100) may have a cross-section defining a groove upon which the rail mounts 205, 305 may slidably slot onto for smooth movement of the carts 200, 300 along the rail 100. Each rail mount 205, 305 may additionally or alternatively comprise at least one bearing which engages with the rail 100 (e.g. bearing rail 100) for smooth movement of the carts 200, 300 along the rail 100.

Optionally the motorised pinion gears 210, 310 driving the two independent carts 200, 300 along the rail 100 may be controlled using a first controller for moving the platform in the x-axis 500x and the z-axis 5GGz. Additionally, the actuator 250 driving the movement of the platform in the y-axis 500y may be controlled using the first controller, or a second controller in communication with the first controller, for moving the platform 400 in one or more of the three dimensions (i.e. along the x-axis 500x, y-axis 500y, and/or z-axis 500z).

Optionally, the actuator 250 driving the movement of the platform in the y-axis 500y may be a linear actuator that moves the platform in a linear direction parallel with the y-axis 500y.

Additionally or alternatively, the platform 400 may hold a tool such as a pincer or other device for picking and placing objects at a desired position in three dimensions. The tool may additionally or alternatively be a device for planting plants/seeds. In addition, the platform may move the tool along the x-axis 500x, y-axis 500y, and/or z-axis 500z in accordance with the embodiments described herein. The platform 400 may additionally or alternatively hold and transfer a load along the x~axis 500x, y~axis 500y, and/or z~axis 500z. For example, the platform may be used for pick and place operations.

Optionally, the arrangement of the connecting rods 510a-510f and their respective ball joints 502a-502f, 502a'-502f relative to the platform 400 and the carts 200, 300 may be achieved by connecting them to the posts extending from the platform 400 rather than to the first, second, and side flanges of the platform 410a, 420a, 430a described herein.

It will be appreciated that further connecting rods may be attached between the carts 200, 300 and the platform 400 to increase the stability of the platform and/or allow the transfer of heavier loads on the platform 400.

It will also be appreciated that instead of bail joints 502a-502f, 502a'-502f other types of rotational joints may be used in the embodiments described herein. Additionally, or alternatively, one or more ball joints 502a-502f, 502a'-502f may be replaced with semi-ridgid or rigid joints to limit movement of the platform in the x, y and or z direction.

Whilst specific examples of the present disclosure are described hereinbefore, it will be appreciated that a wide range of modifications and alterations may be made thereto without departing from the scope of the present disclosure, as defined by the following claims.

Claims

1) A device comprising:

a first and a second independently driven cart slidably attached to a rail for translation along the rail;

a platform connected to the first cart via at least a first connecting rod and to the second cart via at least a second connecting rod,

wherein translation of the first and/or second cart along the rail provides motion in an x and/or a z direction to the platform, the x direction being parallel with the direction of translation of the first and/or second cart along the rail and the z direction being perpendicular to the x direction; and

an independently driven actuator connected to the first connecting rod to move the first connecting rod relative to the rail so as to move the platform in a y direction that is perpendicular to the x and the z directions.

2) The device according to claim 1 wherein the actuator is positioned on the first cart.

3) The device according to claim 1 wherein the actuator is positioned on the platform.

4) The device according to any preceding claim wherein the actuator is connected to the first connecting rod via a lever that extends away from the actuator, and wherein movement of the actuator moves the lever to move the first connecting rod relative to the rail so as to move the platform in the y direction.

5) The device according to claim 4 wherein the first connecting rod is connected to the lever via a ball joint.

6) The device according to any preceding claim wherein the actuator is connected to one end of the first connecting rod.

7) The device according to any preceding claim wherein the actuator is a rotating

actuator or a linear actuator.

8) The device according to any preceding claim wherein the actuator is driven by an electric motor.

9) The device according to any preceding claim wherein the movement of the actuator is in a plane that is inclined relative to a plane parallel with the x and y directions.

10) The device according to any preceding claim wherein the second connecting rod is directly connected onto the second cart and onto the platform.

1 1) The device according to any preceding claim wherein the first connecting rod is in connection with a side of the platform that extends in a direction between a first end of the platform that faces the first cart and a second end of the platform that faces the second cart.

12) The device according to claim 1 1 wherein the device further comprises a third and a fourth connecting rod connecting the platform to the first cart, wherein the third and the fourth connecting rods are parallel with each other and attached to the first end of the platform. 13) The device according to claim 1 1 or 12 wherein the second connecting rod is in connection with the second end of the platform.

14) The device according to any of claims 11 to 12 wherein the device further comprises a fifth and a sixth connecting rod connecting the platform to the second cart, wherein the fifth and sixth connecting rods are parallel with the second connecting rod, and the fifth connecting rod is attached to the second end of the platform, and the sixth connecting rod is attached to the platform between the second and fifth connecting rods and away from the second end of the platform such that the points of connection of the second and the sixth connecting rod define a parallelogram.

15) The device according to any preceding claim wherein one or more of the connecting rods are connected to the platform and the first or second cart via one or more ball joints.

16) The device according to any preceding claim wherein the platform carries a weeding tool.

17) A system comprising a plurality of devices according to any of claims 1 to 16 wherein the plurality of devices are arranged adjacent to each other in an array.

18) A system according to claim 17 wherein the plurality of devices are arranged

adjacent to each other such that a workspace over which the platform of at least one device in the array may move at least partially overlaps with a workspace over which the platform of a neighbouring device may move, the neighbouring device being adjacent to the at least one device.

19) A system according to any of claims 17 to 18 wherein the array is a one dimensional array, a two dimensional array, or a three dimensional array.

20) A method for moving a platform connected to a first cart via at least a first connecting rod and to a second cart via at least a second connecting rod, the first and second carts being independently driven and slidably attached to a rail for translation along the rail, the method comprising:

translating the first and/or the second cart along the rail to provide motion to the platform in a x and/or a z direction to the platform, the x direction being parallel with the direction of translation of the first and/or second cart along the rail and the z direction being perpendicular to the x direction; and driving an actuator connected to the first connecting rod to move the first connecting rod relative to the rail so as to move the platform in a y direction that is perpendicular to the x and the z directions.

21) The method according to claim 20 wherein the actuator is positioned on the first cart.

22) The method according to claim 20 wherein the actuator is positioned on the platform.

23) The method according to any of claims 20 to 22 wherein the actuator is connected to the first connecting rod via a lever that extends away from the actuator, and wherein the method comprises driving the actuator to move the lever so as to move the first connecting rod relative to the rail and thereby move the platform in the y direction.

24) The method according to claim 23 wherein the first connecting rod is connected to the lever via a ball joint. 25) The method according to any of claims 20 to 24 wherein the actuator is connected to one end of the first connecting rod.

26) The method according to any of claims 20 to 25 wherein the actuator is a rotating actuator or a linear actuator.

27) The method according to any of claims 20 to 26 wherein the actuator is driven by an electric motor.

28) The method according to any of claims 20 to 27 comprising driving the actuator

connected to the first connecting rod in a plane that is inclined relative to a plane parallel with the x and y directions to move the first connecting rod relative to the rail so as to move the platform in a y direction.

29) The method according to any of claims 20 to 28 wherein the second connecting rod is directly connected to the second cart and to the platform.

30) The method according to any of claims 20 to 29 wherein the first connecting rod is in connection with a side of the platform that extends in a direction between a first end of the platform that faces the first cart and a second end of the platform that faces the second cart.

31) The method according to claim 30 wherein the device further comprises a third and a fourth connecting rod connecting the platform to the first cart, wherein the third and the fourth connecting rods are parallel with each other and attached to the first end of the platform.

32) The method according to claim 30 or 31 wherein the second connecting rod is in connection with the second end of the platform.

33) The method according to any of claims 30 to 32 wherein the device further comprises a fifth and a sixth connecting rod connecting the platform to the second cart, wherein the fifth and sixth connecting rods are parallel with the second connecting rod, and the fifth connecting rod is attached to the second end of the platform, and the sixth connecting rod is attached to the platform between the second and fifth connecting rods and away from the second end of the platform such that the points of connection of the second and the sixth connecting rod define a parallelogram.

34) The method according to any of claims 20 to 33 wherein one or more of the

connecting rods are connected to the platform and the first or second cart via one or more ball joints.

35) The method according to any of claims 20 to 34 further comprising picking and/or placing a plant/seed with a planting tool attached to the platform, or weeding with a weeding with a weeding tool attached to the platform.