End-effector, method for harvesting a fruit, harvesting system

Abstract

Automated harvesting of a longitudinal fruit, such as a cucumber with a vehicle in a greenhouse and a robot arm to which an end-effector is mounted on a robot arm, the end-effector comprising a frame element for at least partially enclosing the fruit in a circumferential direction of the fruit and in a longitudinal direction of the fruit, a cutting element for cutting a stalk of the fruit, wherein the cutting element is adjustable between an activated position for cutting a stalk of the fruit and a non-activated position.

Description

[0001] Title: End-effector, method for harvesting a fruit, harvesting system

[0002] The invention relates to an end-effector for harvesting a fruit having an upper end with a stalk attached to a plant and a lower end, typically a longitudinal fruit such as a cucumber, in a greenhouse environment.

[0003] Such fruit having an upper end with a stalk attached to a plant and a lower end can be a longitudinal fruit, but in fact can be any type of fruit having an upper end and a lower end wherein the upper end is attached to the plant with a stalk. Such fruit can be cucumbers, but also egg plants or peppers, sweet peppers, tomatoes, both individual as in a bunch, etc. Such fruits are frequently grown in a controlled environment agriculture housing, such as a greenhouse. In such controlled environment agriculture, the plants are typically grown in a vertical manner or in a horizontal manner. In both ways, the fruits hanging from such plants may be distributed over the height of the plants. Nowadays, these fruits are harvested manually. Instead of a fruit, a vegetable can also be harvested. Attempts have been made to automate or semi-automate the harvesting process. Typically, automated or semi-automated harvesting may be done by using a vehicle on which a robot arm is mounted. The robot arm may then be equipped with a gripper for contacting the fruit. However, these attempts see difficulties due to the fact that the plants are rich on leaves that may hide the fruits and / or their stalks. Also, the fruit to be harvested may be obstructed by other fruits or by the plant itself and / or the greenhouse architecture. For example, in certain high-wire greenhouse setups with horizontally oriented plants, their relative positioning may lead to fruit obstruction. Also, it appears that the fruits are sensitive for bruising by the grippers contacting them. Therefore, there is a need for an improved harvesting system. An object of the invention is to provide for a harvesting system that obviates at least one of the above identified problems.

[0004] To that end, the invention provides for an end-effector to be mounted on a robot arm the end-effector comprising a frame element for at least partially enclosing the fruit in a circumferential direction of the fruit and in a longitudinal direction of the fruit, and a cutting element provided on the frame element for cutting a stalk of the fruit, wherein the cutting element is adjustable between an activated position for cutting a stalk of the fruit and a non-activated position. The longitudinal direction of the fruit can be considered the direction between the upper end and the lower end of the fruit. It is understood that not all fruits are straight along this direction, but can be curved, e.g. a cucumber or sweet pepper that grew curved. Harvesting of a fruit, not cutting of a leave, is envisaged. A fruit is typically larger and heavier than a leave, and may require a different approach and / or solution.

[0005] It is understood that instead of a fruit, a vegetable can also be harvested using the end-effector according to the invention or with the method according to the invention. For conciseness, the wording fruit is being used in this disclosure, but where fruit is used, vegetable can be understood as well. It also may be understood that a bunch of fruits, e.g. vine tomatoes or truss tomatoes, or grapes, that is harvested as one fruit is a fruit according this disclosure.

[0006] By providing an end-effector comprising a frame element for at least partially enclosing the fruit in a circumferential direction and in a longitudinal direction, no intended engagement between the frame element and the fruit is required. The longitudinal direction is understood to be more or less in line with a direction between a free hanging end of the fruit and an opposite end, to which the stalk is connected, of the fruit. The end of the fruit to which the stalk is connected is referred to as the upper end. The end of the fruit opposite the upper end, being the free hanging end of the fruit, is referred to as the lower end of the fruit. The end-effector is in particular suitable for long fruits, such as cucumber, pepper, eggplant for which a longitudinal direction may relatively easy be established. In case of more round fruits, such as apples, oranges etc. the longitudinal direction can also be understood to be a direction from the connection point of the stalk to the fruit towards an opposite free hanging end of the fruit. The circumferential direction is understood to be a direction following a circumference of the fruit in a plane transverse to the longitudinal direction.

[0007] The frame element at least partially encloses the fruit without contacting the fruit. The fruit can be at least partially enclosed without holding it. Even when the frame element at least partially encloses the fruit, there remains freedom of movement of the frame element with respect to the fruit, indicating that the frame element does not hold or engages the fruit to manipulate it. Accidental contact or engagement, for example during movement of the frame element with respect to the fruit, can be possible without damaging the fruit. As such, the frame element can be advantageously designed, as it can be of a rigid structure, and complex structures such as moving fingers or adaptable cushions can be obviated. For example, the frame element may be provided as a shell or as a cylindrical tube. The frame element may be rigid, such as a rigid shell or a rigid tube. Advantageously, the frame element may accommodate various diameters of fruits and may allow some play between an inner side of the frame element and the fruit. Advantageously, the frame element is configured to at least partially enclose the fruit without gripping it. Since gripping of the fruit can be obviated, the fruit may be less damaged and / or the frame element can be of a relative simple design.

[0008] Advantageously, the frame element is provided as a single element, as opposed to the prior art at least two or more gripping fingers. The single element may for example be a shell element for partially circumferentially surrounding the fruit, or a tubular element for fully circumferentially surrounding the fruit. The frame element itself is also a static element, in the sense that there are no movable parts at or to the frame element. Advantageously, the only movable parts at the end-effector are the at least one cutting element.

[0009] The frame element may extend in a longitudinal direction of the fruit and in circumferential direction of the fruit, so the frame element has a height a first direction and may be curved in a direction transverse to the first direction. As such, the frame element has a curvature in a plane transverse to the first direction over at least a section of a circumference in said plane. The circumference may be circular or oval or polygonal. In an example, the frame element extends over at least half of the circumference in the second direction, and thus may form a kind of shell element that may surround at least half of the circumference of the fruit. In use, when the frame element is partially or fully surrounding the fruit, the first direction of the frame element is preferably in the same direction as the longitudinal direction of the fruit.

[0010] The frame element may approach the fruit such that it can at least partially surround the fruit, and may move along the fruit up and / or downward. Approach of the fruit may be done sideways and / or from below. When approaching the fruit sideways, the frame element may slightly abut the fruit to at least partially enclose it, indicating that slight contact is possible but that there is no holding of the fruit. When approaching the fruit from below, the frame element may partially enclose the fruit without holding it. Since there is no holding of the fruit and / or the frame element may allow some play between the fruit and the frame element, although accidental contact can occur, the fruit can be protected from damaging and / or bruising thereby increasing the quality of the harvested fruit. Due to a more simple structure of the frame element, the end-effector can be more cost effective, which may improve the payback period of investments in automated or semi-automated harvesting.

[0011] The frame element may be a semi-cylindrical shell being open at one side to partially enclose the fruit. A radius of the shell may be somewhat larger than a radius of the fruit to be harvested such that the shell can partially enclose the fruit without holding or squeezing it. Further, a length of the frame element may be shorter than a length of the fruit to be harvested, the length of the fruit being considered the distance between the upper end and the lower end along the longitudinal direction of the fruit. As such, the frame element may at least partially enclose the fruit in circumferentially direction and in longitudinal direction.

[0012] The end-effector further comprises at least one cutting element for cutting the stalk of the fruit, which fruit is at least partially enclosed by the frame element. The cutting element is adjustable between an activated position for cutting the stalk and a non-activated position. In the nonactivated position, the cutting element is at rest. The cutting element typically can be a bladed instrument, e.g. a knife, or a scissor, that is extendable or rotatable mounted in or to the end-effector, or a scissor, such that in the activated position it can cut the stalk of the fruit. In the nonactivated position, the cutting element is stored such that it is free of the enclosed fruit and / or of the stalk. The cutting element may thus be a single, or at least one of the few, movable components of the end-effector, allowing the end-effector to be of a simple and cost effective design. At least one cutting element can be provided. It may be envisaged that two cutting elements may be arranged to the end-effector, e.g. opposite each other to provide for a reliable cutting. The cutting element may be housed within the end-effector both in activated position as in non-activated position, preferably at least in activated position. The cutting element may also not extend outside of the end-effector in particular in non-activated position to avoid interaction with the plant, leaves or other fruit. As such, when the fruit is at least partially enclosed by the rigid shape of the frame element, an interaction point between the cutting element and the plant, in particular the stalk, is enclosed as well, meaning that there may be no accidental damage to other plant parts.

[0013] In use, the end-effector is mounted to a robot arm which robot arm moves the end-effector to the fruit to be harvested. Advantageously, the robot arm moves the end-effector towards the fruit to be harvested such that the frame element can at least partially enclose the fruit. When the frame element is a partially open frame element, such as a shell, the frame element may approach the fruit from below or sideways. The frame element may then partially enclose the fruit. Advantageously, a lower end of the fruit is at least partially enclosed as a lower end may be more visible and / or more approachable than the entire fruit. The entire fruit and / or the stalk of the fruit, may be hidden from view due to leaves or other fruit hanging over or above it. The lower end of the fruit often remains visible, and as such can be approached by the frame element. When the frame element at least partially encloses the lower end of the fruit, it may advance along the fruit in an upward direction towards an upper end of the fruit. The upper end of the fruit is understood to be the end of the fruit to which the stalk is connected. The stalk connects the fruit to a branch of the plant growing the fruit. When the upper end of the fruit is reached, the cutting element can be activated to cut the stalk of the fruit. During ascending of the frame element along the fruit, the frame element may act as guidance element to the fruit allowing gentle contact without gripping.

[0014] Prior to approaching the fruit from below or sideways, preferably a lower end of the fruit has been detected. Such detection may be done by a vision system mounted on the vehicle of the harvesting system. Such vision system is known and typically may comprise one, two or more camera’s to detect visible parts of the fruit, as well as a controller for processing the collected data and determining a position of the detected fruit. Alternatively, the frame element may be a circumferentially closed element, such as a ring-shaped element or a tubular element or a funnel- shaped element. Such circumferentially closed element advantageously approaches the fruit from below and is being directed by the robot arm to the lower end of the fruit, which lower end may be visible and thus being approachable and / or detectable. The lower end of the fruit is then being received inside of the frame element, an inner diameter of the frame element being larger than the diameter of the fruit to allow some play between an inner side of the frame element and the fruit. Then, the frame element is being advanced along the fruit towards the upper end of the fruit. During this advancement or ascending of the frame element along the fruit, there may be incidental contact between the fruit and the frame element, however such contact is sufficiently gently that the fruit may not be damaged. For an optimal advancement of the frame element along the fruit, an orientation of the longitudinal direction of the fruit may be determined. Then, the frame element may be advanced along the determined orientation. The determined orientation of the fruit is being used as the advancement direction, as such, the fruit itself does not need to be used as guidance, thus minimizing contact and / or impact on the fruit itself. The orientation of the longitudinal direction of the fruit may be determined by the vision system that is mounted on the vehicle.

[0015] When the upper end of the fruit is reached, the cutting element can be activated towards its activated position to cut the stalk of the fruit. Movement of the frame element along the fruit can be done by the robot arm to which the end-effector is mounted. Alternatively and / or additionally, the frame element is longitudinally movable with respect to the end-effector, allowing the frame element a degree of freedom with respect to the endeffector for a translation movement along the fruit while the end-effector itself can be kept in position by the robot arm. This may allow a more accurate movement of the frame element along the fruit. Such a longitudinal movement may be embodied in various well-known ways, e.g. as a rack-and-pinion, or as a carriage-rail or as a detent in a groove, etc. Such local degree of freedom of the frame element may also allow for a more simple control of the movement. Instead of controlling the robot arm to provide the longitudinal movement along the fruit, by integrating this longitudinal movement in the end-effector local control of the movement may be possible. Then, the robot arm may only need to bring the endeffector to the fruit and to return the end-effector. The robot arm may then not need to move outside its field of view, which may induce additional complexity on the robot arm and the control thereof.

[0016] The frame element can be configured to approach the fruit from below and to ascend along the fruit to the upper end of the fruit. The frame element may for example be configured circumferentially closed e.g. as funnel or a truncated cone having an entry side with a larger opening than an exit side to easily approach and receive the lower end of the fruit, or circumferentially partially open, e.g. as a semi-cylindrical shell. By ascending along the fruit to the upper end, the fruit is being guided towards the exit opening. Alternatively, the frame element may for example flare out at the entry side to allow relative easy access of the lower end of the fruit into the frame element. Advantageously, an entry element is provided at the entry side of the frame element. Such entry element may be specifically designed to receive a certain fruit. In an embodiment, the entry element may for example be circumferentially closed while the frame element may be partially open, or vice versa. The entry element may specifically be configured to guide the lower end of the fruit towards the frame element without causing damage to the fruit and / or to the plant. The entry element may also be configured to push away obstacles, such as other fruit or leaves, around the fruit and / or end-effector without damaging the plant. The entry component of the end-effector can have a dual function. For example, the entry element may have a rounded edge of which the radius is between approximately 2 mm - 7 mm, preferably about 5 mm. Further, the entry element may be provided with a skirt outwardly flaring from the rounded edge towards the frame element. The outwardly flaring skirt preferably has a concave shape to minimize damage to the fruit in case an entry opening of the entry element is missed or when other fruits and / or leaves are to be pushed away during advancement of the frame element to the upper end of the fruit.

[0017] Activation of the cutting element is preferably done when the upper end, with the stalk attached thereto, of the fruit is detected. Depending on the type of fruit, detection of the stalk itself may be envisaged, or a combination of detection of the upper end and detection of the stalk. Such detection may be done by one or more sensors. Various types of sensors may be used. For example, a tactile sensor may be used, e.g. a spring mounted finger touching the fruit that extends over a threshold when the upper end of the fruit is reached and the finger either contacts the stalk or extends into the environmental air. Alternatively and / or additionally, a visual sensor may be used detecting the fruit, and when the upper end is reached no fruit is detected anymore. Alternatively and / or additionally, a distance measuring sensor can be used, measuring the distance to the fruit, and when the upper end of the fruit is reached the distance is increased above a predefined threshold, e.g. above a radius of the frame element. Many other sensors and combinations of sensors may be used. At least one sensor is preferred, however a single sensor may in some circumstances result in a false positive measurement. Then, two, three or more sensors circumferentially positioned may be used to result in an accurate measurement.

[0018] Activation of the cutting element can be done by an activation element, such as a motor mounted on the end-effector, or may be done by the robot arm. Thereto, the end-effector, and / or the frame element, may be provided with a mounting element for mounting to the robot arm, wherein the mounting element provides for electrical and / or data connection with the robot arm. The end-effector may be provided with the mounting element allowing the frame element to translate with respect to the end-effector along the fruit while the end-effector is kept in position with respect to the fruit by the robot arm connected to the mounting element. The electrical connection may allow for example for activation of the cutting element and / or for actuation of the frame element when it is provided with a translation degree of freedom and / or to power the sensors. Other connections may be envisaged, such as a hydraulic connection or a pneumatic connection, either of which may be used to activate the cutting element. The end-effector may be provided with a control unit e.g. to process the data obtained by the at least one sensor. Alternatively and / or additionally, a control unit of the robot arm and / or of the vehicle may be used to control the end-effector, for example by processing the data obtained by the at least one sensor and / or determining when the upper end of the fruit is reached. A data connection in the mounting element between the end-effector and the robot arm may then be provided to allow transmission of the data to and from the end-effector.

[0019] Advantageously, the cutting element is arranged at an entry side of the frame element. As such, when reaching the upper end of the fruit, the cutting element is optimally positioned to cut the stalk of the fruit.

[0020] The end-effector may further comprise a sensor element, which sensor element comprises the at least one sensor. The sensor element may be integrated to the frame element, e.g. the sensors may be provided in an inner side of the frame element. Alternatively, the sensor element may be provided between the frame element and the cutting element. Preferably, the sensors are positioned relatively close to the cutting element, such that, when the end of the fruit is detected, the cutting element is optimally positioned to cut the stalk of the fruit. By positioning the sensor element between the cutting element and the frame element, or in the frame element nearby the cutting element, wherein the cutting element is preferably provided at the entry side of the frame element, the sensor element is positioned relatively close to the cutting element, such that when the end of the fruit is detected by the sensor, that the cutting element is surely free of the fruit for cutting the stalk only. Also, the frame element then still may at least partially enclose the fruit for allowing the fruit, when the stalk is cut, to fall towards a storage position in a controlled manner. By providing the at least one sensor at an inner side of the end-effector, the sensor element observe an inner space of the end-effector in which the fruit is being enclosed. Thus, the sensor element can observe without being obstructed by e.g. adjacent fruits or leaves of the plant or other environmental circumstances such as light or moisture. The sensor element may provide for a reliable observation since only the fruit is enclosed by the end-effector which fruit is being detected. At least one sensor is provided, which can be sufficient to detect the fruit. Alternatively, three or five sensors may be provided which advantageously are positioned on a same circumference of an inner side of the end-effector, in an even distribution. Providing more than one sensor may allow for a robust and reliable detection.

[0021] Advantageously, a height of the frame element or a distance between the entry side of the frame element and an exit side of the frame element, is smaller than a typical length of the fruit to be harvested. So, when the fruit is being received in the frame element, part of the fruit will extend further than the height of the end-effector. As such, the frame element partially encloses the fruit in longitudinal direction. To reduce or minimize damage to the fruit to be harvested, it is advantageous that the frame element is shorter than the length of the fruit, thus reducing a potential contact area between the frame element and the fruit and / or to allow for curvature of the fruit to be harvested. Depending on the fruit to be harvested the height of the end-effector can be determined. Preferably, the frame element has an inner diameter, albeit circumferentially partially open or circumferentially closed, that is slightly larger than the diameter range of the fruits to be harvested, thus allowing a smooth advancing of the frame element along the fruit towards its upper end. Such larger diameter also may allow to accommodate curvature and / or irregularities of the fruit to be harvested.

[0022] Further, the end-effector may comprise a receiving sleeve for receiving the fruit. Since, typically, the height of the frame element is smaller than the length of the fruit to be harvested, part of the fruit extends further than the frame element during advancement of the frame element along the fruit, then, it is advantageous that the extending part of the fruit is being received in the receiving sleeve. In particular, when the frame element is circumferentially closed, together with the receiving sleeve, a closed environment can be created for the fruit in which the fruit is being isolated from the outer environment, such as leaves and other fruits. Manipulation of the fruit can then being done in a controlled manner, from enclosing the fruit to cutting the stalk and depositing the harvested fruit. Also, when creating a closed environment in which the fruit can be contained during cutting and thereafter, the risk on infection of a cutting surface of the stalk can be reduced. Also, the risk on damage on adjacent fruits or the plant or even a person by the cutting element can be obviated, allowing for a safe harvesting. This also may allow the at least one sensor of the sensor element to work in a controlled environment by obviating any obstacles that might impede a detection of the sensor.

[0023] Additionally, the end-effector may be provided with a disinfection element that disinfects the cutting element after each cutting action. This can be done particularly advantageous when the frame element is circumferentially closed and thus a closed environment is created for the cutting element. By creating such a closed environment, the disinfection can be controlled and contamination from outside the end-effector may be minimized and / or reduced. Such disinfection element may be provided as a spray element that sprays disinfection liquid onto the cutting element, which disinfection liquid is supplied from a container. The container can be kept inside, or outside or integrated to the end-effector. Many more variants of a disinfection element may be possible.

[0024] Advantageously, the receiving sleeve is configured to hold the fruit when it is harvested. To that end, the receiving sleeve preferably has a closed bottom. The receiving sleeve may be of a rigid structure, like a tube, or may have a more flexible structure, like a bag. Such flexible structure may beneficially accommodate any irregularities in the shape of the fruit, e.g. some curvature. With a flexible structure of the sleeve, damage to the fruit may be minimized or avoided. The receiving sleeve may be provided with a closable bottom, e.g. an adjustable lid, to allow outputting of the harvested fruit. Then, after harvesting, the fruit remains contained in the receiving sleeve and the robot arm may move the end-effector with harvested fruit towards a collecting station, e.g. a storage container on the vehicle. Once the fruit is above the collecting station, the closable bottom can be opened to allow the fruit to be released from the receiving sleeve and to be put in the collecting station. Activation of the closable bottom, e.g. as an adjustable lid, is preferably done via the robot arm, after determination of the position of the end-effector above the collecting station. Alternatively and / or additionally, the end-effector may be provided with a stalk holding element to hold the stalk of the fruit to be harvested during cutting. Such stalk holding element is preferably arranged below the cutting element, such that it can hold the stalk, and the fruit, after it is being cut. As such the fruit can be held in the end-effector after it has been cut, and it may be prevented from falling through the end-effector after being cut. Such stalk holding element can be provided also when the end-effector is not provided with a receiving sleeve. Even when a receiving sleeve, with or without bottom, is provided, the holding element may be arranged to the end- effector. Such holding element advantageously holds the stalk, not the fruit body itself, to avoid damage to the fruit. The stalk holding element may be fingers or grippers for holding the stalk. The holding element advantageously is arranged between the frame element and the cutting element. Alternatively, in case no receiving sleeve and / or no stalk holding element may be provided a separate and / or second robot arm provided with a collecting case may be provided to collect the fruit after the stalk being cut. The fruit may then be directly held in the collecting crate. Such a collecting case may be arranged to receive a single fruit, such that after each cutting action, the second robot arm returns to the collection station to deposit the collected fruit at the collection station and returning empty to the next fruit to be cut. In another example, the sleeve may be embodied as a flexible hose guiding the harvested fruit directly towards a collecting station that may follow the robot to which the end-effector is mounted. Many embodiments may be envisaged for receiving and / or guiding and / or collecting the fruit after its stalk is cut.

[0025] The cutting element and the frame element and / or the at least one sensor and / or the entry element can be integrated to the frame element to form a single, compact component. Alternatively, the end-effector can be a modular assembly of a frame module and a cutting module and / or a sensor module and / or an entry module and / or a disinfection module. The frame module comprises the frame element and the mounting element for mounting to the robot arm. The cutting module comprises the cutting elements and may be configured to removable fit to the frame module. The cutting module preferably comprises the at least one cutting element, and if more cutting elements are envisaged, the cutting module preferably comprises all the cutting elements. For example, the frame module and the cutting module may both have corresponding fitting elements that allow simple and swift engaging and disengaging of the modules to and from each other. Such fitting elements may be through holes through which bolts can be fastened, or may be click fingers fitting in corresponding bores, etc. Such a frame module may then be adaptable depending e.g. on the size of the fruit to be harvested. Typically, fruits are harvested in predefined diameter ranges, so, when a different diameter range is to be harvested, the frame module may be exchanged for a frame module suitable for the different diameter range. Alternatively, the frame module may have a base with an exchangeable insert, that is selected from inserts with different diameters, corresponding with the diameter range to be harvested. In case a holding element is provided, the holding element may be configured as a holding module. Such holding module may then be arranged between the frame module and the cutting module, such that the holding element may hold the stalk of the fruit below a cutting position where the cutting element may cut the stalk. Optionally, the holding element may be integrated to the cutting module to provide a minimum distance between a position of holding the stalk and a position of cutting the stalk. This may be advantageous for fruits with short stalks.

[0026] Also, the cutting module may be exchanged depending on the stalks fruit to be harvested. By providing such a modular end-effector, the end-effector can easily be adapted to varying circumstances, as well as, in case of failure of one of the modules, these can easily be replaced. Further, a sensor module may be provided comprising the sensor element with the at least one sensor. The sensor module optimally is positioned between the frame module and the cutting module, such that, when the sensor module detects the upper end of the fruit, the cutting element of the cutting module is optimally positioned to cut the stalk of the fruit. The sensor module too may be provided with fitting elements corresponding to the fitting elements of the frame module and the cutting module, as to allow easy exchangeability. Further, an entry module can be provided that may be positioned on the cutting module. The entry module as well may have corresponding fitting elements, to fit to the cutting module. The cutting module can be exchanged, depending on the needs of the fruits to be harvested. By providing a frame module, a cutting module and / or a sensor module and / or an entry module, each selected from a set of frame modules, cutting modules and / or sensor modules and / or entry modules respectively, a modular end-effector can be obtained using individually tested and approved components that can be assembled to the optimal end-effector for the fruits to be harvested. By providing a modular system for the endeffector of which each module has corresponding fitting elements that allow easy connection between the various modules, the end-effector may be optimized for the fruit-to-be-harvested. The fitting elements may be embodied as corresponding flanges that can be engaged with bolts, or can be embodied as a snap-fit connection or can be embodied as a bayonet connection, etc. It may be understood that various embodiments of fitting elements can be possible. For example, it can be understood that for each fruit to optimally cut the stalk of the fruit, a dedicated cutting element may be provided. With a modular system, the cutting module can be easily exchanged with a different cutting module for a different type of fruit. Or even during a harvesting cycle for the same fruit, the cutting module can be easily exchanged with a new cutting module, e.g. when the cutting element has become blunt during the harvesting cycle. Similarly, other modules of the modular end-effector may be exchanged.

[0027] The invention further provides for a method for harvesting a fruit having an upper end with a stalk attached to a plant and a lower end, providing an end-effector to be mounted on a robot arm. The end-effector is provided with a frame element and a cutting element. The robot arm moves the frame element towards the fruit to be harvested to at least partially enclose the fruit in circumferential direction and in longitudinal direction. The frame element is then being ascended along the fruit towards an upper end thereof. When the upper end is reached is the stalk being cut by a cutting element provided to the frame element. The method at least partially encloses the fruit without gripping, pressing or otherwise touching it, to reduce and / or minimize damage and / or bruising of the fruit. In fact, use is made of the hanging position of the fruit. Due to the hanging position, the lower end of the fruit often may be visible while an upper end and / or the stalk may often be obstructed from vision by other fruits and / or leaves of the plant and / or the greenhouse architecture. So, when approaching the lower end of the fruit, a visible part of the fruit can be approached. Then, by advancing along the fruit towards the upper end, an at least partially enclosing relation to the fruit can be kept, also when approaching towards a non-visible part of the fruit. While advancing, other fruits and / or leaves may be pushed away.

[0028] The fruit may be approached sideways, which typically is possible when the frame element is partially open in circumferentially direction, such as a shell, e.g. a semi-cylindrical shell. Alternatively, the fruit may be approached from below, to move the end-effector towards the fruit in an approach direction that is preferably approximately colinear with a longitudinal direction of the fruit. However, depending on the position of the fruit an approximately colinear approach is not always possible, then the approach direction of the end-effector may be under an angle with respect to the longitudinal direction of the fruit. Once the fruit is in the frame element, the angular position of the frame element can be adjusted to substantially align the longitudinal axis of the frame element with the longitudinal direction of the fruit. Adjusting the angular position may be done by a swivel motion induced by the robot arm, optimally being a swivel motion around a point coinciding with the attachment of the stalk to the stem. When altering the position of the end-effector with a swivel motion around the stalk attachment point, minimum effect is obtained on the fruit, which is beneficial for the integrity and the quality of the fruit.

[0029] When the orientation of the end-effector is approximately aligned with the longitudinal direction of the fruit, the frame element can be advanced along the fruit in upward direction until the upper end of the fruit is detected, preferably by at least one sensor mounted to the end-effector. For advancing the frame element along the fruit, the orientation of the longitudinal direction of the fruit preferably is determined. Then, the advancement of the frame element can follow the determined orientation and there is no need to use the fruit itself as guidance. This also may reduce contact with and / or manipulation of the fruit to be harvested.

[0030] When the upper end of the fruit is detected, the stalk can be cut by the at least one cutting element. The harvested fruit may be received in a receiving sleeve, which may, or may not, be closed at its bottom. When the receiving sleeve is open at the bottom, the harvested fruit may be outputted directly to a collecting station, e.g. a belt for transporting the harvested fruit to a further location. Such collecting station may be positioned underneath the end-effector by a, optionally other, robot arm. When the receiving sleeve is closed at the bottom, the robot arm may move the end-effector with the fruit in the receiving sleeve to a collecting station, and when positioned above the collecting station, the bottom can be opened to output the harvested fruit to the collecting station. Such collecting station may be a storage container on the vehicle.

[0031] By approaching the lower end of the fruit and advancing along the fruit to the upper end thereof, use is being made of the hanging orientation of the fruit, and minimum manipulation of the fruit itself needs to be done. Use is being made of gravity to allow the fruit to be lowered in the receiving sleeve after the stalk is cut. When no receiving sleeve is used, another receiving means can be foreseen to collect the harvested fruit after cutting the stalk. Thus, handling of the fruit can be done gently, without gripping, pressing or otherwise engaging the fruit. Here, contact of the fruit with the frame element is possible, but since preferably not the fruit is used as guidance, but the orientation of the fruit is used as advancement direction, ascending along the fruit can be done gently and smoothly, minimizing damage and / or bruising of the fruit.

[0032] The invention further relates to a harvesting system comprising a vehicle to which a robot arm is mounted, the robot arm provided with such an end-effector.

[0033] Further advantageous embodiments are provided in the subclaims.

[0034] These and other aspects will be further elucidated with reference to the drawing comprising figures of exemplary embodiments. Corresponding elements are designated with the same or corresponding reference signs. In the drawing shows:

[0035] Figure 1 a first embodiment of an end-effector according to the invention;

[0036] Figure 2 a second embodiment of an end-effector according to the invention;

[0037] Figure 3 an embodiment of a modular end-effector according to the invention;

[0038] Figures 4a - 4g the steps for harvesting a fruit with an end-effector according to the invention.

[0039] It is to be noted that the figures are given by way of exemplary examples and are not limiting to the disclosure.

[0040] Figure 1 shows an end-effector 1 according to the invention for harvesting a fruit, such as a cucumber. The end-effector 1 comprises a frame element 2 and a cutting element 3. The frame element 2 is configured to at least partially enclose the fruit in a circumferential direction and in a longitudinal direction. Here, the frame element 2 is embodied as a shell that can partially surround the fruit. It is provided as a single piece, as opposed to prior art multiple gripping fingers. Further, the end-effector 1 comprises a cutting element 3. The cutting element 3 is here embodied as a knife that is rotatable mounted to a side wall 4 of the frame element 2. Here, there is a single cutting element provided, but two or more cutting elements may be possible. The cutting element 3 is adjustable between an activated position in which it can cut the stalk of a fruit enclosed by the frame element. The cutting element 3 is here shown in a non-activated position in which it is free from a fruit or stalk that is enclosed by the frame element 2. Here, the cutting element 2 is stored in the side wall 4 of the frame element 2 in the non-activated position. In the activated position, the cutting element 2 is being rotated towards an inner space 5 of the frame element 2 in which the fruit is partially enclosed. Rotation of the cutting element 3 is done around a rotation axis R. The cutting element 3 can be rotatable mounted to the frame element 2 e.g. via a rotation shaft or a bolt extending through bore 6 along the rotation axis R. Further, the end-effector 1 is configured to be mounted to a robot arm. The end-effector 1 is thereto provided with a mounting element 7 providing for mechanical, and preferably also electrical connection with the robot arm. The electrical connection, not shown, may be used to activate the cutting element 3 from the non-activated position towards the activated position for cutting the stalk of the fruit and / or to bring the cutting element 3 back to the non-activated position after cutting. In an example, by providing the frame element, the cutting element and the mounting element, the only actuatable element in the end-effector may be the cutting element, while the robot arm provides for the positioning of the end-effector as a whole.

[0041] The frame element 2 is configured to enclose the fruit without gripping the fruit. The frame element 2 may thus be provided with a semi- cylindrical receiving space 5, as is shown here, in which the fruit can be partially enclosed. The semi-cylindrical receiving space 5 is here provided by the shell 2 of the end-effector 2. Since there is no gripping or touching or holding of the fruit needed, the frame element 2 can be of a simple design. The frame element 2 can also be embodied as a rigid component, as in this example a rigid shell, since deliberate holding of the fruit is not envisaged, no soft regions or cushions need to be provided for engaging the fruit, nor complex moving fingers for gripping the fruit.

[0042] In fact, a diameter D of the receiving space 5 is preferably somewhat larger than the diameter range of the fruits to be harvested. Fruits are typically harvested in a specified diameter range, e.g. a range of 30 - 35 mm diameter, 35 - 40 mm diameter, or 40 - 45 mm diameter, or 45 - 50 mm diameter, etc. The diameter of the receiving space 5 may then be, as an example, 37 mm, 42 mm or 47 mm or 52 mm respectively. So, even with the largest diameters fruit, some play is allowed between the frame element 2 and the fruit avoiding that the fruit can become clamped by the frame element 2, and allowing a smooth enclosing of the fruit to be harvested. Also, a height H of the frame element 2 is preferably smaller than a typical length range of the fruits to be harvested. As such, the fruit can be partially enclosed in the longitudinal direction as well, and there is less risk on the fruit becoming stuck in the frame element, e.g. due to a curvature in the fruit. In an optimal enclosure of the fruit by the frame element 2, a longitudinal axis L of the frame element 2 coincides with a longitudinal direction of the fruit. The longitudinal axis L of the frame element preferably is a central axis of the frame element 2, being colinear or approximately colinear with a central axis of the fruit. It is understood that a fruit may have a varying and / or irregular shape, so that it may be difficult to determine a central axis. The axis in longitudinal direction of the fruit that is most centrally, may then be considered the central axis for the purpose of the harvesting with the end-effector 1.

[0043] By providing a shell-shaped frame element 2, being a frame element 2 that can partially enclose the fruit in a circumferential direction and in the longitudinal direction, the fruit can be approach from a side thereof. The end-effector 1 is being moved towards the fruit by the robot arm to which it is connected, until it partially encloses the fruit. Alternatively, the fruit can be approached from below the fruit, and the robot arm may move the end-effector 1 from below the fruit to around the fruit until the fruit is being partially enclosed by the frame element 2. One side of the endeffector 1 may be an entry side 8 and an opposite side of the end-effector 1 may an exit side 9. The frame element 2 approaches the fruit from below, such that the fruit is being received through the entry side 8. Since the height H may be smaller than a length of the fruit, part of the fruit may extend through the exit side 9 out of the frame element 2. Thus, the fruit is being partially enclosed by the frame element 2, both in circumferential direction as in longitudinal direction.

[0044] The cutting element 3 is preferably arranged near the entry side 8 of the frame element 2, as shown in figure 1. As such, when the fruit is enclosed by the frame element 2 and an upper end of the fruit is at or near, preferably below, the entry side 8, then the cutting element 3 is more likely to cut the stalk of the fruit when activated. Thus, it can be avoided, or minimized that the cutting element 3 cuts the flesh of the fruit.

[0045] Alternatively, the frame element 2 can be embodied as to fully enclose the fruit in circumferential direction, e.g. the frame element 2 can then be ring-shaped. The height H of the frame element 2 advantageously remains smaller than a typical length of the fruit to be harvested. Figure 2 shows an embodiment of the end-effector 1 with a frame element 2 that is of a tubular shape, or a ring shape, to fully circumferentially enclose the fruit to be harvested. The frame element 2 is here too provided with a mounting element 7 for connection with a robot arm. Mechanical connections 7a as well as electrical and / or data connections 7b are provided.

[0046] The cutting element 3 comprises a cutting blade 31 mounted on an arm 32. The arm 32 is rotatable mounted around rotation axis R and rotation shaft 33. An actuator 34 provides for the actuation of the cutting element 3 from the non-activated position to the activated position. In figure 2, the cutting element 3 is shown in the activated position. In the nonactivated position, the cutting element 3 can be stored in a collar 35 of the cutting element 3. The cutting element 3 is provided at an entry side 8 of the frame element 2, i.e. an upper side of the end-effector, such that, when an upper end of the fruit is positioned at the entry side of the end-effector, that the stalk of the fruit is being cut. Since the cutting element 3 operates in the receiving space 5 of the end-effector 1, so in a space isolated from the environment, the cutting operation can be performed more safely since no accidental damage to other parts of the plant or to a person can be done.

[0047] The end-effector 1 shown in figure 2 is configured to approach the fruit from below. Then, a lower end of the fruit is being received first in the end-effector 1. To facilitate entry of the fruit in the end-effector 1, the entry side 8 can be provided with an entry element 10 for guiding the lower end of the fruit into the end-effector and / or for moving obstacles such as leaves or other fruit away from the end-effector. The entry element 10 is ring-shaped and has a rounded upper edge 11. The diameter of the rounded upper edge 11 is such to minimize or avoid damage to fruit and / or plant. Preferably, the rounding diameter of the rounded upper edge 11 is about 2 - 8 mm, more preferably around 5 mm. An inner diameter DI of the upper edge 11 can be the same as the diameter D of the receiving space 5 of the frame element 2. Alternatively, the inner diameter D 1 can be larger than the inner diameter D of the frame element 2 to guide the fruit towards the receiving space 5. Further, the entry element 10 comprises a skirt 12 outwardly flaring from the upper edge 11 downwardly and outwardly. By providing such outwardly flaring skirt, obstacles such as leaves and / or other fruits can be pushed away from the end-effector 1 to clear the entry side for receiving the fruit to be harvested.

[0048] When the fruit is being approach from below, the lower end of the fruit is being received through the entry element 10 into the frame element 2. Then, the end-effector 1 is being moved upwardly towards an upper end of the fruit along a longitudinal direction of the fruit. When the upper end of the fruit is reached, the cutting element 3 is activated to cut the stalk of the fruit. To detect whether an upper end of the fruit is reached, at least one sensor 20 is provided in the end-effector 1. Here, three sensors 20 are provided to an inner side of the frame element 2. The sensors 20 are distributed evenly over the circumference of the inner side, so with an angle of approximately 120 degrees between them. The sensors 20 can be visual sensors or tactile sensors, here a visual sensor is provided. The sensors 20 look, or feel, into the inner space 5 of the frame element 2. Thereby, the observation of the sensors 20 is not obstructed by obstacles such as leaves or other fruits nor may it be influenced by the circumstances, such as light or moisture, in the agriculture environment. By providing the at least one sensor 20 to the end-effector 1, wherein the at least one sensor 20 observes an inner space 5 of the end-effector 1 a more reliable observation of the sensor 20 can be obtained, as it may not be obstructed by other factors apart from the fruit to be detected.

[0049] The at least one sensor 20 is also arranged near an upper side of the frame element 2, in particular, it is advantageous that the at least one sensor 20 is arranged close to and below of the cutting element 3. Then, when the upper end of the fruit is detected based on the observations of the sensor 20, in a reliable manner, the cutting element 3 can be activated to cut the stalk of the fruit which is located above the upper end of the fruit.

[0050] The at least one sensor 20 may be a distance sensor detecting the distance of the fruit during ascending of the end-effector 1 along the fruit upwardly. When the detected distance exceeds a certain predefined threshold, e.g. a radius D / 2 minus some margin, it can be determined that the upper end of the fruit has been reached and that the stalk is now in front of the sensor. So, reliably, the cutting element 3 can be activated to cut the stalk.

[0051] By providing a circumferentially closed frame element 2, a contained receiving space 5 for the fruit can be provided, in which environmental influences or obstacles can be obviated, allowing reliable observations of the at least one sensor. The at least one sensor is arranged to observe an inner space of the end-effector 1.

[0052] The end-effector 1 further can comprises a receiving sleeve 40, here mounted to the exit side 9 of the frame element 2. The receiving sleeve 40 is configured to receive a part of the fruit that extends out of the frame element 2. Since the height of the frame element 2 with the entry element 10 is smaller than a typical length of the fruit, part of the fruit extends at the exit side 9 out of the frame element 2. This part of the fruit can be received in the receiving sleeve 40. The receiving sleeve 40 can be rigid, e.g. a tube, or flexible, e.g. a bag. The receiving sleeve 40 is preferably circumferentially closed to provide for a contained environment for the fruit. The circumferentially closed frame element 2 together with the receiving sleeve 40 provides for isolation of the fruit from its environment, i.e. the plant. Not only the sensors 20 can thus provide more reliable observations, due to less obstructions, but also handling of the fruit is less influenced by the environment, such as the plant. In particular, since cutting of the stalk is done in a more isolated environment, the cutting surface may be less infected, thereby adding to the health and / or quality of the harvested fruit.

[0053] Advantageously, the receiving sleeve 40 is at its bottom 41 provided with a closable lid 50. After cutting of the stalk of the fruit, the fruit moves downward under influence of gravity and abuts the lid 50. So, also after harvesting, the fruit remains in the isolated environment of the end-effector 1. Then, the robot arm can move the end-effector 1 with the contained fruit towards a collecting station. Once positioned above the collecting station, the lid 50 may be actuated to an open position to allow the fruit to exit the sleeve 40 and to be put in, e.g. a storage container, of the collecting station. Activation of the closable lid 50, which can be rotatable mounted to the bottom 41 of the sleeve, can be done by an actuator 51, which can e.g. be powered via the robot arm. The end-effector 1 can be of an integrated design, wherein the frame element 2 and the cutting element 3 are integrated to one another, as e.g. shown in Fig. 1. Alternatively, the end-effector 1 can be of a modular design, in which the end-effector 1 is a modular assembly comprising a frame module 2M and a cutting module 3M, and / or an entry module 10M and / or a sensor module, as e.g. shown in Fig. 3. The frame module 2M comprises the frame element 2 is provided with fitting elements 60 that engage with corresponding fitting elements of the adjacent module. Here the fitting elements 60 are embodied as a flange 61 with bores through which bolts 62 can be fastened. The frame module 2M is engaged to the receiving sleeve 40 at its lower side 9 and is engaged to the cutting module 3M at its upper side. The cutting module 3M comprises the cutting element 3. Above the cutting module 3M, the entry module 10M is positioned. The entry module 10M comprises the entry element 10. Each module is selected from a set of different modules to specifically select the module that is adapted for the fruits to be harvested. For example, if fruits with a specific diameter range are to be harvested, the frame module is advantageously selected such that the inner diameter of the frame element is slightly larger than the intended fruit diameter range to allow smooth enclosing of the fruit to be harvested. For example, depending on the species of fruit to be harvested, the entry module can be selected such that it is adapted to the fruit and to the plant to optimally receive the fruit and / or to optimally move away any obstacles. Similarly for the cutting module which can be selected to have a cutting element that is specifically intended to cut the stalks of the fruits to be harvested. Also a sensor module can be provided. The sensor module then comprises the at least one sensor. In the example of figure 3, the sensors are integrated in the frame element, but alternatively, a sensor module may be provided between the frame module and the cutting module. Then, the sensors are close to the cutting element, such that, when the upper end of the fruit is detected, the stalk can be cut in a reliable manner. Figures 4a - 4g show subsequent steps of a method for harvesting a fruit in a controlled environment agriculture, such as a greenhouse with a vehicle 100 on which a robot arm 101 is mounted. The end-effector 1 is mounted to the robot arm 101. The end-effector 1 can be an end-effector 1 as shown in figure 1, figure 2 or figure 3, or any other end-effector having a frame element for at least partially enclosing the fruit in a circumferential direction of the fruit and in a longitudinal direction of the fruit, a cutting element for cutting a stalk of the fruit, wherein the cutting element is adjustable between an activated position for cutting a stalk of the fruit and a non-activated position.

[0054] The vehicle 100 is provided with a vision system having a field of view FOV as shown in fig. 4a. With the vision system, fruits are identified while the vehicle is driving through the greenhouse path. As can be seen, the stalks of the fruits can be obstructed from view to leaves or another fruit. Using the end-effector according to the invention, it is sufficient to detect lower ends of the fruits. The vision system detects lower ends of fruits and determines the probability of success for harvesting. When a fruit is determined that is to be harvested, the robot arm 101 brings the endeffector 1 towards the lower end of the fruit. Optionally, an orientation of the fruit is determined prior to approaching the fruit with the end-effector. Fig. 4b shows the step in which the orientation of the hanging fruit is determined. Also, in this step, obstacles 90, such as leaves can be identified by the vision system of the vehicle 100. The orientation of the fruit mainly corresponds with an angle of a longitudinal direction of the fruit with respect to a vertical plane. When the orientation is determined, the endeffector 1 can be moved to approach the fruit from below. An approach direction is indicated in figure 4c. As can be seen in figure 4c the approach direction may not always correspond with the orientation of the fruit. Then, once the lower end of the fruit is received in the end-effector, shown in figure 4d, either the end-effector can be swiveled to an orientation corresponding with the orientation of the fruit, or, when there is e.g. httle space around the fruit, the end-effector 1 with the fruit can be swiveled to create more space. Such swiveling motion is schematically illustrated in figure 4e. The end-effector 1 is schematically shown. By pivoting the endeffector 1 approximately around the connection of the stalk to the stem, the fruit with the end-effector can be swiveled to a position in which there is more space around the fruit to accommodate the end-effector. By pivoting the fruit around the connection of the stalk to the stem, the fruit can be manipulated without damaging it and / or its stalk. As such, the longitudinal axis of the end-effector 1 may be aligned with the longitudinal direction of the fruit, such that, advantageously a central axis of the end-effector is colinear with a central axis of the fruit, insofar as a central axis of a fruit, that is by definition not perfect and has irregularities, can be determined.

[0055] Once the longitudinal direction of the end-effector is aligned with the longitudinal direction of the fruit, e.g. by the swiveling movement as shown in figure 4e, the end-effector 1 may be advanced to the upper end of the fruit along the longitudinal direction of the fruit. Advantageously, the orientation of the fruit was determined by the vision system prior to the approach, or when the fruit is being pivoted as in step 4e, the orientation is known as well. Then, the robot arm 101 can advance the end-effector 1 along the defined orientation, such that the fruit need not be used as guidance. This provides a more smooth handling of the fruit reducing the risk on damage and / or bruising.

[0056] When the upper end of the fruit is reached, and is detected by the at least one sensor of the end-effector, the cutting element of the endeffector can be activated to cut the stalk of the fruit, illustrated in figure 4f. The fruit then is being received in the receiving sleeve where it abuts the bottom of the receiving sleeve. Then, the robot arm can bring the endeffector with the fruit in the sleeve to a collecting station, e.g. a storage container 102 on the vehicle 100. When the receiving sleeve is positioned above the storage container 102, the adjustable lid can be opened to allow the fruit to exit the receiving sleeve and to be put in the storage container. The robot arm 101 can then move to the next fruit to be harvested.

[0057] The disclosure relates to automated harvesting of a fruit having an upper end with a stalk attached to a plant and a lower end, such as a cucumber with a vehicle in a greenhouse and a robot arm to which an endeffector is mounted on a robot arm, the end-effector comprising a frame element for at least partially enclosing the fruit in a circumferential direction of the fruit and in a longitudinal direction of the fruit, a cutting element for cutting a stalk of the fruit, wherein the cutting element is adjustable between an activated position for cutting a stalk of the fruit and a non-activated position.

[0058] For the purpose of clarity and a concise description, features are described herein as part of the same or separate embodiments, however, it will be appreciated that the scope of the claims and disclosure may include embodiments having combinations of all or some of the features described. It may be understood that the embodiments shown have the same or similar components, apart from where they are described as being different.

[0059] In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. The word ‘comprising’ does not exclude the presence of other features or steps than those listed in a claim. Furthermore, the words ‘a’ and ‘an’ shall not be construed as limited to ‘only one’, but instead are used to mean ‘at least one’, and do not exclude a plurality. The mere fact that certain measures are recited in mutually different claims does not indicate that a combination of these measures cannot be used to an advantage. Many variants will be apparent to the person skilled in the art, and are understood to be comprised within the scope defined in the following claims.

Claims

Claims1. End-effector for harvesting of a fruit having an upper end with a stalk attached to a plant and a lower end, such as a cucumber, the endeffector to be mounted on a robot arm, the end-effector comprising:- a frame element for at least partially enclosing the fruit in a circumferential direction of the fruit and in a longitudinal direction of the fruit,- at least one cutting element for cutting a stalk of the fruit, wherein the at least one cutting element is adjustable between an activated position for cutting a stalk of the fruit and a non-activated position.

2. End-effector according to claim 1, wherein the frame element is configured to at least partially enclose the fruit without gripping.

3. End-effector according to claim 1 or 2, wherein the frame element is configured to approach the fruit from below and to ascend along the fruit from a lower end of the fruit to an upper end of the fruit.

4. End-effector according to any of the preceding claims, wherein the cutting element is configured to be adjusted to the activated position when the upper end of the fruit is detected.

5. End-effector according to any of the preceding claims, wherein the cutting element is arranged at an entry side of the frame element.

6. End-effector according to any of the preceding claims, wherein the frame element comprises an entry element for guiding the lower end of the fruit into the frame element.

7. End-effector according to claim 6, wherein the cutting element is arranged between the frame element and the entry element.

8. End-effector according to any of the preceding claims, wherein the frame element is ring-shaped to entirely enclose the fruit in a circumferential direction.

9. End-effector according to any of the preceding claims, wherein frame element comprises an exit side opposite the entry side, wherein a distance between the entry side and the exit side is smaller than a typical length of the fruit to be harvested.

10. End-effector according to any of the preceding claims, further comprising a receiving sleeve mounted to the frame element for receiving the fruit.

11. End-effector according to claim 10, wherein the receiving sleeve is configured to hold the harvested fruit.

12. End-effector according to claim 10 or 11, wherein the receiving sleeve is configured to output the harvested fruit, preferably via an adjustable lid.

13. End-effector according to any of the preceding claims, further comprising at least one sensor to detect whether the upper end of the fruit has been reached.

14. End-effector according to claim 13, wherein the at least one sensor is provided in a sensor element, the sensor element preferably arranged between the frame element and the cutting element.

15. End-effector according to any of the preceding claims, wherein the frame element is provided with a mounting element for mounting to the robot arm, the mounting element providing for electrical and / or data connection with the robot arm.

16. End-effector according to any of the preceding claims, wherein the end-effector is an assembly comprising a frame module and a cutting module, wherein the frame module comprises the frame element and the cutting module comprises the cutting element to provide for a modular endeffector.

17. End-effector according to claim 16, wherein the frame module and the cutting module each are selected from a set of frame modules and a set of cutting modules respectively to provide a modular end-effector adapted to the longitudinal fruit to be harvested.

18. End-effector according to claim 16 or 17 and according to claim 6 and / or to claim 13, further comprising an entry module comprising the entry element and / or a sensor module comprising the sensor element, preferably selected from a set of entry modules and / or a set of sensor modules respectively to provide for a modular end-effector adapted to the longitudinal fruit to be harvested.

19. End-effector according to any of the claims 16 - 18, wherein the end-effector is an assembly of the frame module, optionally the sensor module, the cutting module and optionally the entry module.

20. Method for harvesting of a longitudinal fruit, such as a cucumber, the method comprising:- at least partially enclosing the fruit at a lower end thereof with a frame element;- ascending the frame element along the fruit towards an upper end of the fruit;- cutting the stalk of the fruit when the upper end is reached with a cutting element provided to the frame element.

21. Method according to claim 20, wherein at least partially enclosing the fruit is done without gripping the fruit.

22. Method according to claim 20 or 21, comprising: approaching the fruit from below the fruit towards the lower end of the fruit to at least partially enclose the fruit at its lower end with the frame element.

23. Method according to any of the claims 20 - 22, comprising, substantially aligning a longitudinal axis of the frame element with the longitudinal direction of the fruit.

24. Method according to any of the claims 20 - 23, further comprising: detecting the lower end of the fruit prior to at least partially enclosing the fruit.

25. Method according to any of the claims 20 - 24, further comprising: determining an orientation of the longitudinal direction of the fruit, preferably ascending the frame element along the determined orientation.

26. Method according to any of the claims 20 - 25, during ascending of the frame element along the fruit, detecting whether the upper end of the fruit has been reached.

27. Method according to any of the claims 20 - 26, further comprising: receiving the fruit in a receiving sleeve.

28. Method according to claim 27, further comprising: holding the harvested fruit in the receiving sleeve.

29. Method according to claim 27 or 28, further comprising: outputting the harvested fruit from the receiving sleeve.

30. Method according to any of the claims 27 - 29, transporting the harvested fruit when in the receiving sleeve to a collecting station and outputting the harvested fruit from the receiving sleeve into the collecting station.

31. Harvesting system for harvesting longitudinal fruit in a controlled environment agriculture, comprising a vehicle to which a robot arm is mounted, the robot arm provided with an end-effector according to any of the claims 1 - 19.

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