NL2016464B1

NL2016464B1 - Harvesting machine.

Info

Publication number: NL2016464B1
Application number: NL2016464A
Authority: NL
Inventors: Van De Werken Theo; Kreling Jan
Original assignee: Kw Techniek V O F
Priority date: 2016-03-21
Filing date: 2016-03-21
Publication date: 2017-10-04

Abstract

A first aspect provides a harvesting device for harvesting a crop. The device comprises a sensor for generating a signal upon detection of crop, a primary gripper for gripping and holding the crop and a cutting module comprising a cutter for cutting the crop. The device further comprises a transportation module for moving cut crop away from a harvesting position, the transportation device having the primary gripper connected thereto. The device also comprises a processing unit arranged to receive the signal from the sensor, control the primary gripper to grip the crop upon reception of the signal control the cutting module to cut the crop after the primary gripper has gripped the crop and control the transportation module to move the cut crop away from the harvesting position. Stems of the crop are oriented in the same direction, under an angle smaller than ninety degrees relative to the ground.

Description

P111075NL00

Title: Harvesting machine

TECHNICAL FIELD

The various aspects relate to a machine and method for harvesting of crop and flowering plants having a flower or a flower bud in particular.

BACKGROUND

Harvesting of flower carrying plants is a labour intensive operation. Plants are guided by a guiding mesh that obstructs operation of an automated cutting tool. Removing the guiding mesh results in the plant falling over and entanglement of the plants. Due to the entanglement, the plans cannot be properly cut anymore, either by hand or by means of a machine.

SUMMARY

An automated process of cutting plants and flower carrying plants in particular and a device for such automated process would be an advantage to the industry. A first aspect provides a harvesting device for harvesting a crop. The device comprises a sensor for generating a signal upon detection of crop, a primary gripper for gripping and holding the crop and a cutting module comprising a cutter for cutting the crop. The device further comprises a transportation module for moving cut crop away from a harvesting position, the transportation device having the primary gripper connected thereto. The device also comprises a processing unit arranged to receive the signal from the sensor, control the primary gripper to grip the crop upon reception of the signal control the cutting module to cut the crop after the primary gripper has gripped the crop and control the transportation module to move the cut crop away from the harvesting position.

This device allows for automatic harvesting of crop, as crop can be harvested upon detection and harvested plants can be transported from the harvesting position one by one. In this way, fragile and delicate plants like flowers can be harvested without substantive loss of leaf or damage to flowers and flower buds.

An embodiment of the device further comprises a secondary gripper for gripping and holding the crop, the secondary gripper being comprised by the cutting module. In this embodiment, the processing unit is further arranged to control the secondary gripper to grip the crop upon receiving the signal; and control the secondary gripper to release the crop prior to transportation of the crop by the transportation module.

This embodiment allows for accurate holding of the crop close to the harvesting position.

In another embodiment, at least one of the primary gripper and the secondary gripper is arranged to grip the crop at a gripping position and subsequently move the crop to a cutting position.

Whereas plants may be planted in a regular grid, nature tends to have a mind of her own and does not always abide with such imposed regularity. Grippers functioning in accordance with this embodiment compensate for this issue by relocating for example a stem of crop towards a position where is may be conveniently cut.

In a further embodiment, the secondary gripper comprises at least one gripping hook arranged for executing a substantially rotary movement for gripping the crop and for subsequently executing a substantially linear movement for moving the crop from the gripping position to the cutting position.

With a rotary movement, a particular area may be covered by scanning. This allows for capturing crop in a relatively wide range. With the linear movement, the crop is efficiently moven towards the cutting position. Hence, each of the movements has an advantage.

In yet another embodiment, the transportation module is arranged for moving the primary gripper in a substantially curved path.

This embodiment allows for a plant to be lifted by the stem, while leaving a top of a plant, for example comprising a flower, at a position where it was before cutting and/or transporting. This reduces risk of damaging the flower or other delicate parts of a plant, like fruits.

In yet a further embodiment, the primary gripper is rotatably mounted to the transportation module, the axis of rotation being under an angle relative to a vertical axis.

This embodiment aids the primary gripper to follow the substantially curved path. More preferably, the axis of rotation has a substantially horizontal orientation. A second aspect provides an arrangement for preparing a crop for harvest. The arrangement comprises a guiding mesh comprising mesh loops for guiding growth of crop and a substantially vertically oriented guiding structure for guiding substantially vertical movement of the mesh. In this aspect, the guiding mesh is connected to the guiding structures such that at least one position of the guiding mesh relative to the guiding structure the guiding mesh is enabled to move in a direction having a horizontal component.

This aspect allows for laying down plants in, for example, a flowerbed in one particular direction. Such position of the flowers may be helpful for certain harvesting processes. A third aspect provides a method of harvesting a crop by means of a device according to the first aspect. The method comprises detecting crop, upon detection of the crop, gripping the crop by means of the primary gripper, after gripping of the crop, cutting the crop at a cutting position and after cutting the crop, transporting the crop away from the cutting position.

An embodiment of the third aspect, wherein the crop is guided by means of the arrangement according to the second aspect, comprises , prior to detecting the crop, lifting the guiding mesh, the lifting comprising a movement having a horizontal component, the movement being executed while crop is present in the mesh loops.

BRIEF DESCRIPTION OF THE DRAWINGS

The various aspects and embodiments thereof will now be discussed in further detail in conjunction with drawings. In the drawings, Figure 1 A: shows a flower bed with plants guided by a guiding mesh;

Figure 1 B: shows a flower bed with plants laying down in one direction;

Figure 2: shows a harvesting machine;

Figure 3: shows a lower gripper module for the harvesting machine;

Figure 4 A: shows a gripper in open position;

Figure 4 B: shows a gripper in closed position;

Figure 5 A: shows a side view of the harvesting machine approaching a plant;

Figure 5 B: shows a side view of the harvesting machine gripping a plant;

Figure 5 C: shows a top view of two cutting bladed for cutting stems of plants;

Figure 5 D: shows shows a top view of two cutting bladed having cut stems of plants;

Figure 5 E: shows a side view of the harvesting machine having cut a plant;

Figure 5 F: shows a side view of the harvesting machine transporting a plant;

Figure 5 G: shows a side view of the harvesting machine having transported a plant; and

Figure 6: shows a flowchart.

DETAILED DESCRIPTION

Figure 1 A shows a flowerbed 100 comprising plants 140 that grow in the ground 110 as a crop. The plants comprise a stem 142 and a flower 144. Alternatively or additionally to the flowers 144, the plants comprise flower buds. Preferably, the plants are Chrysanthemum.

During the growth of the plants 140, the flowers are guided by a wire mesh 120. As plants 140 grow, the height of the wire mesh 120 above the ground 110 may be increased. The pace at which the wire mesh 120 is lifted may be the same as the pace at which the plants 140 grow or at a lower pace. Lifting the wire mesh 120 at half the growth rate of the plants 140 may be convenient to keep the wire mesh 120 at about half the stem of the flowers 140. A mesh lifting module 150 may be provided for lifting the wire mesh 120. To that end, the mesh lifting module 150 may comprise a driving unit 152 like an electromotor connected to a winch 154 for winding up a line 156 coupled to the mesh 120.

The wire mesh, in turn, is guided by one or more guiding poles 130. The guiding pole 130 comprises a first elongated section 132 that is, as shown by Figure 1 A, arranged to be provided substantially vertically in or on the ground 100. This allows the wire mesh 120 to be lifted in a substantially vertical way, as long as the height of the mesh does not exceed the length of the first elongated section 132.

If the wire mesh 120 is lifted higher, the wire mesh 120 is guided by a second elongated section 134. The second elongated section 134 is connected to the first elongated section 132. Preferably, the second elongated section 134 is tilted in a direction in a direction parallel to the longitudinal direction of the flowerbed 100 or, alternatively, perpendicular thereto. This has as a result that when further lifted, the wire mesh also moves in a horizontal direction.

Upon lifted the wire mesh 120 beyond the length of the first longitudinal section 132, following the second longitudinal section 134, the plants 140 are tilted in the same direction as the second elongated section 134 is tilted to. If the wire mesh 120 is further lifted, beyond the length of the plants 140, the tilting of the stems 142 of the plants 140 will result in the plants 140 falling over as the support of the wire mesh 120 to the stems is removed. This is depicted by figure 1 B. This position of the plants 140 is a preferred position for harvesting the plants 140. The plants 140 are preferably laid down in this position at a moment close to harvesting -preferably less than 24 hours.

Figure 2 shows a harvesting machine 200 for harvesting the plants 140 laid down in a position as depicted by Figure 1 B. The harvesting machine 200 comprises a frame 202 to which various parts of the harvesting machine 200 are connected. The harvesting machine 200 comprises a vertical guiding rail 212 for guiding a vertical movement of a carriage 214. The carriage 214 is arranged for guiding horizontal movement of a carrying arm 216. The harvesting machine 200 comprises a vertical driving module for driving the vertical movement of the carriage 214. The harvesting machine 200 also comprises a horizontal driving module for driving the horizontal movement of the carrying arm 214.

To the carrying arm 216, an extension arm 218 is mounted. In this embodiment, the extension arm 218 is fixedly mounted to the carrying arm 216 under an angle. Alternatively, the extension arm 218 may be movably mounted to the carrying arm 216 such that the angle may be varied. To the extension arm 218, an upper gripper module 220 is provided. The upper gripper module 220 is rotatably mounted to the extension arm 218 and is rotatable over a rotation axis 228. To the upper gripper module 220, upper grippers 222 are mounted.

At the lower part of the frame 202, a lower gripper module 230 is provided. The lower gripper module 230 will be discussed in further detail below. At the bottom of the frame 202, a tracked driving module 204 is provided. Alternatively or additionally, wheels or other traction modules may be provided. Preferably, the harvesting machine 200 is self-propelled, comprising at least one propulsion driving module for driving the tracks. Alternatively, remote, possibly static, propulsion driving modules are provided for moving the harvesting machine 200 between two or more positions, for example by means of lines.

Figure 3 shows the lower gripper module 230 in further detail. The lower gripper module 230 comprises a mounting module 310 for mounting the lower gripper module 230 to the frame 202 of the harvesting machine 200. In a preferred embodiment, the lower gripper module 230 is movably mounted to the frame 202. More in particular, it is preferred the lower gripper module 230 is mounted such to the frame 202 that it may be linearly movable relative to the frame 202, in particular vertically and horizontally, perpendicular to the direction of movement of the harvesting machine 200. The driving of the lower gripper module 230 relative to the frame 202 is preferably facilitated through hydraulic or pneumatic actuators.

The lower gripper module 230 further comprises a guiding plate 320 comprising indentations 324 provided between guiding teeth 322. At the most recessed points of the indentations 324, grippers 400 are provided. The gripper 400 is discussed below in greater detail. The guiding plate 320 is slidably movable substantially parallel to the direction of movement of the harvesting machine 200. In a preferred embodiment, the grippers 400 are fixedly mounted to the lower gripper module, which means the guiding plate 320 is movable relative to the grippers 400.

The sliding plate is provided with a strike plate 334. The strike plate 334 is arranged to engage with a detector 322 acting as a sensor. The strike plate 334 engages with a button 338 of the detector 332 if the guiding plate 320 is in its most backward position. Preferably, this is at a point where the most recessed points of the indentations 324 substantially coincide with an edge of a housing 410 of the grippers 400, as depicted by Figure 3.

The lower gripper module 230 further comprises a guiding actuator module 336 for pushing the guiding plate 320 forward relative to the frame 202 of the harvesting machine 200, away from the mounting module 230. The guiding actuator module 336 is preferably a hydraulic or pneumatic actuator enabling a linearly reciprocating movement.

At the lower part of the lower gripper module 230, shoes 340 are provided for protection of further parts of the lower gripper module 230 against the ground 110. In one embodiment, the shoes 340 support fully support the lower gripping module 230. In another embodiment, the lower gripper 230 module is fully or at least partially supported by the connection of the mounting module 310 to the frame 202.

Figure 4 A shows the gripper 400 in further detail. More in particular, Figure 4 A shows the gripper 400 in an open position. The gripper 400 comprises the housing 410. In the housing two gripping claws 420 are provided in a movable way. The gripping claws 420 comprise a substantially straight part 424 extending from the housing 410. At outer ends, away from the housing 410, hooks 422 are provided. By actuating a control hook 440 by moving the control hook 440 away from the housing 410, a control slide 442 is moved out of the housing 410. The gripping hooks 420 are connected to the control slide 442 and move along with the control slide 442.

The housing 410 comprises guiding members for guiding movement of the gripping claws 420. The guiding members and the gripping claws 420 are provided such that upon the control hook 440 moving out of the housing 410, the gripping claws 420 firstly move towards one another in a symmetrical way. In this movement, the hooks 422 firstly follow a substantially curved, preferably circular, trajectory until the meet or are either very close.

Subsequently, the straight parts 424 are retracted in the housing 410 in a substantially linear movement. The end of the curved movement may coincide with a first part of the linear movement trajectory. And advantage of closing the lower gripper 400 prior to the linear movement is that this allows plant 140 to be gripped and pulled to a position where the plant 140 may be conveniently cut. Whereas plants 140 are usually planted in lines in a grid, they may in some cases grow in irregular ways and out of the grid pattern. This way of operation of the grippers compensates for such irregularities.

In the retracted position of the gripping claws 420, an opening 412 is provided between the hooks 422 and a gripper indentation 450. The size of the opening 412 may be varied by varying the size of the gripper indentation 450 and/or the size of the hooks 422.

Figure 5 A shows a side view of the lower gripper module 230 and the upper gripper module 220. Figure 5 A also shows a plant 140 that is in the same position as depicted by Figure 1 B. The plant 140 has a stem 142 that, towards the ground 110, has a substantially vertical orientation. The plant 140 also comprises a bud 144. A higher part of the stem 142 is bent towards a group of other plants that is schematically depicted by a triangle 160. The stem 142 is in Figure 5 A drawn curved. Alternatively or additionally, certain parts of the stem 142 are straight and have a diagonal orientation relative to the ground 110. In addition to parts discussed in conjunction with Figure 2, Figure 3 and Figure 4, the lower gripper module 230 comprises a gripper support 342 and a cutter 344.

Figure 5 B shows the harvesting machine 200 having moved towards the plant 140. This results in the guiding plate 320 moving towards the stem 142 of the plant 140. As the guiding plate 320 is slidably mounted to the lower gripper module, the guiding plate 320 is moved into a position in which the strike plate 334 engages with the button 338 of the detector 332. Upon the button 338 being pushed, the detector 332 sends out a signal to a processing unit. Upon receiving this signal, the processing unit instructs the driving module 204 to stop propelling the harvesting machine 200.

Furthermore, the processing unit instructs the harvesting machine 200 to let the upper gripper 222 grip the stem 142 of the plant 140 by means of upper claws 224. Also, the lower gripper 400 is instructed to grip the stem 142 by means of lower gripping claws 420. In particular the upper gripper 222 holds the stem 142 in a firm grip. The lower griper 400 may hold the stem 142 in a loose grip. Whereas the side view provided in Figure 5 A and Figure 5 B shows only one plant 140, multiple plants 140 may be and preferably are provided in line. With the gripper modules comprising multiple grippers, the plants 140 in line are each gripped by grippers, one of each gripping module.

Subsequently, the stem 142 is cut. The stem 142 is cut by a reciprocating movement of the gripper support 342 and the cutter 344. This is shown by Figure 5 C and Figure 5 D. Figure 5 C and figure 5 D show an upper view of the gripper support 342 and the cutter 344. Figure 5 C shows the gripper support 342 and the cutter 344 having indentations that are aligned, with stems 142 in each indentation. The indentation in the gripper support 342 and the cutter 344 coincide in this embodiment with the indentations 324 in the guiding plate 320.

Upon the stems 142 being held by the lower grippers 400 and the upper grippers 222, the gripper support 342 and the cutter 344 are moved relative to one another in a linear movement as shown by Figure 5 D by control of the processing unit. As the indentations of the gripper support 342 and the cutter 344 are sharpened, the stems 142 are cut. In another embodiment, a separate second cutter is provided instead of the gripper support to provide the cutting action in conjunction with the cutter 344.

Figure 5 E shows the plant 140 and the harvesting machine 200 in the same position as in Figure 5 B. The stem 142 of the plant, however, is cut in a stump 148 and a stem upper part 146.

After the stem 142 has been cut, the cut part of the plant 140 is released by the lower gripper 400 and moved away from the harvesting position by means of the upper gripper module 220 and the carrying arm 216. This is shown by Figure 5 F. This action is controlled by the processing unit. Figure 5 F shows the carrying arm 216 moved to a higher position, by driving the carriage 214 up and by driving the carrying arm.

In this embodiment, the upper gripper module 220 is moved such to leave the bud 144 resting on the group of other plants as long as possible. This is achieved by moving the upper gripper module 220 via a curved trajectory, optionally having a substantial circular shape and by rotating the upper gripper module 220 over the rotation axis 228. This enables the plant 140 to be lifted and moved away from the harvesting position as shown by Figure 5 E, with reducing any potential friction between the bud 144 and the other plants still present on the flower bed 100.

Figure 5 G shows the plant 140 held by the upper gripper 222 in an upside down position. Figure 5 G shows a first rotational path of the upper gripper 222 by a dashed line and a second rotational path of the rotation axis by a dash-dot line. In the upside down position of the upper gripper 222, the plant 140 is transported to another location. This may be a location within the frame 202 of the harvesting machine 200 and/or a position further away, outside harvesting machine 200. The plant 140 may be transported for further processing like binding, sorting, quality control, other or a combination thereof.

After the plant 140 has been detected, gripped, cut and moved to the position as shown by Figure 5 G, the upper gripper 222 is moved back to the position as shown by Figure 5 A and the guiding plate 320 is moved back to the position as shown by Figure 5 A by means of the guiding actuator module 336. Subsequently, prior to this or simultaneously, the driving module 204 is activated by the processing unit for further propulsion of the harvesting machine.

An overview of the procedure followed is provided by means of a flowchart 600 provided by Figure 6. The various parts of the flowchart 600 are briefly summarised below: 602 start procedure 604 plant plants 606 grow plants 608 plants ready for harvest? 610 lift wire mesh 612 activate harvesting machine 614 detect plant 616 grip plant with upper gripper 618 grip plant with lower gripper 620 cut plant 622 release lower gripper 624 transport plant 626 all plants done? 628 end harvesting 630 re-initialise machine 632 move machine

The procedure starts in a start terminator 602. Subsequently, the procedure continues with planting a crop of one or more plants 140 in step 604. The plant 140 is grown in step 606 and regularly checked in step 608 whether the plant 140 is ready for harvest. If the plant 140 is ready for harvest, the wire mesh 120 is lifted and the plants 140 are laid down as depicted by Figure 1 B in step 610.

After the plants 140 have been laid down in one direction, in parallel to the harvesting direction or the direction of propulsion of the harvesting machine 200, the harvesting machine 200 is activated in step 612. The harvesting machine 200 is propelled as discussed above, until one or more plants are detected in step 614 as discussed above. Next, the propulsion of the harvesting machine 200 stops. The plant is gripped by means of the upper gripper 222 in step 616 and optionally by means of the lower gripper 400 in step 618. In step 620, the plant 140 is cut. Prior to moving the plant 140 away from the harvesting position in step 624, the lower gripper 400 is released in step 622.

After the plant 140 has been transported, it is checked in step 626 , for example by means of the processing unit, whether all plants 140 in a flower bed 100 have been cut. If this is the case, the harvesting is ended in a terminator 628.

If not all plants have been harvested, the harvesting machine is reinitialised in step 630 by moving the upper grippers 222 back to a position for gripping a new plant 140 and moving back the guiding plate 340 back to its detecting position. Subsequently, simultaneously or earlier, the harvesting machine is set in motion again in step 632.

It should be noted various parts of the harvesting machine may be embodied in different ways. For example, the detector 332 with the button 338 may be replaced or complemented by other means of detections of plants 140, for example by means of optical detection of the plants. This may for example by implemented by means of a laser beam, emitting light in a line where a plant 140 is best situated for cutting. Obstruction of the laser beam, detected by means of a light detector as light is not received at another side of the harvesting machine 200 anymore or light is scattered by the plant 140 and received, indicates the harvesting machine 200 is in a position for cutting.

Furthermore, whereas the curved trajectory for transportation of the cut plant 140 has been shown in conjunction with linear movements of the carrying arm 216 and the carriage 214, such curved trajectory may also be implemented by means of a single arm that is suspended such that it moves in the same or a similar trajectory.

Also, the indentations in the guiding plate 320 may be omitted as the open gripping claws 420 of the grippers 400 may perform a similar function. Alternatively, the lower grippers 400 may be omitted altogether as for the mere functionality of the harvesting machine, the upper grippers 222 suffice. In such embodiment, the detector 322 and the gripper support 342 and the cutter 344 are preferably mounted to the upper gripper module 220. Alternatively, these components are mounted to the lower gripper module 230, without the lower grippers 400 being mounted to the lower gripper module 230.

Nonetheless, presence of the lower grippers 400 enhances functionality of the harvesting machine 200.

With respect to guiding of the plants 140 and laying the flowers down as depicted by Figure 1 B, the plants 140 may also be laid down in another way. The guiding mesh 120 may also be moved relative to the plants 140 in another way rather than following the guiding poles 130 along the second elongated section that is placed under an angle relative to the first elongated section. Another guiding pole comprising one elongated substantially straight element may be envisaged as well and the guiding mesh 120 may be moved during lifting is by other means.

Claims

A harvesting device for harvesting a crop, the device comprising: A sensor for generating a signal upon detection of the crop; A primary grab for grabbing and holding the crop; A cutting module comprising a cutter for cutting the crop; A transport module for moving cut crops away from a harvesting position, the transport module comprising the primary gripper connected thereto; A processing unit adapted to: receive the signal from the sensor; Control the primary grab to grab the crop upon detection of the signal; Control the cutting module to cut the crop after the primary grab has grabbed the crop; and Control the transport module to remove the cut crop from the harvest position.

2. Device as claimed in claim 1, further comprising a secondary gripper for gripping and holding the crop, the secondary gripper being comprised by the cutting module, the processing unit being adapted to: The secondary gripper to control the crop upon receipt of the signal ; and control the secondary grab to release the crop for transportation of the crop through the transportation module.

Device as claimed in any of the foregoing claims, wherein at least one of the primary grab and the secondary grab is adapted to grab the crop at a grab position and then move it to a cutting position.

Device as claimed in claim 3, wherein the secondary gripper comprises at least one gripping hook which is adapted to perform a substantially rotating movement for gripping the crop and for subsequently performing a substantially linear movement for moving the crop from the gripping position to the cutting position.

Device as claimed in any of the claims 2 to 4, wherein the primary grab and the secondary grab are adapted to grab a substantially vertically oriented stem or stem of the crop.

Device as claimed in any of the claims 2 to 5, wherein the cutting module comprises a guide part comprising a notch, which guide part is adapted to move from a first position to a second position relative to the cutter, which second position is closer to the cutter is then the first position and the sensor is triggered to generate the signal when the guide member is in the second position.

The device of claim 6, wherein the secondary gripper is connected to the guide member at a deepest point of the notch.

Device as claimed in any of the foregoing claims, wherein the transport module is adapted to move the primary gripper in a substantially curved path.

Device as claimed in any of the foregoing claims, wherein the primary gripper is rotatably connected to the transport module, the rotation axis being placed at an angle with a vertical axis.

Device as claimed in any of the foregoing claims, further comprising a drive unit for advancing the device.

The device of claim 10, wherein the processing unit is further adapted to: control the drive unit to stop moving the device upon receipt of the signal; and Continue propelling the device when the cut crop has been transported to a predetermined position.

12. Device for preparing a crop for harvesting, the device comprising: A guide net comprising net meshes for guiding growth of the crop; and a substantially vertically oriented guide structure for guiding a substantially vertical movement of the net; The guide net being connected to the guide structures such that at least one position of the guide net relative to the guide structure can move the guide net in a direction with a substantially horizontal component.

Device as claimed in claim 12, wherein the guide structure comprises elongated parts connected to the net which enable movement of the net in a direction parallel to the guide parts, the guide parts comprising: A first elongated substantially straight part; A second elongated substantially straight portion connected to the first portion at an angle.

A method for harvesting a crop by means of a device according to any one of claims 1 to 11, comprising: Detecting the crop; Upon detection of the crop, grasping the crop by means of the primary grab After grasping the crop, cutting the crop at a cutting position; After cutting the crop, transport the crop away from the cutting position.

Method for harvesting a crop according to claim 14, wherein the crop is guided by means of a device according to claim 12, comprising, prior to detection of the crop, lifting the guide net, lifting comprising a movement which comprises a substantially horizontal component, which movement is carried out with the crop in the net meshes.

A method according to any of claims 14 or 15, wherein transporting the crop comprises rotating the first gripper such that the crop is turned upside down.

The method of claim 16, wherein transporting the crop further comprises moving the primary gripper along a substantially curved path such that an upper portion of the crop remains in substantially the same position.