SE2050611A1

SE2050611A1 - Method and system for remote or autonomous tree harvesting

Info

Publication number: SE2050611A1
Application number: SE2050611A
Authority: SE
Inventors: Markus Romar; Mauritz Andersson; Olle Gelin
Original assignee: Airforestry Ab
Priority date: 2020-05-27
Filing date: 2020-05-27
Publication date: 2021-11-28
Also published as: WO2021239704A1; SE2051336A1; SE2051335A1; SE544809C2; SE544184C2; SE544874C2

Abstract

The invention relates to A system (10) for remote and/or autonomous harvesting at least a portion of a tree, said system (10) comprising: a remotely and/or autonomously controlled means (110) configured for harvesting said at least a portion of a tree, a remotely and/or autonomously controlled Unmanned Aerial Vehicle (100), UAV, comprising, at least one means for holding (105) said harvested portion of said tree and being configured for transporting said harvested portion of said tree away from the original location of the tree, wherein said system comprising at least one means for detecting said tree to be harvested, and a base station (120) for communication with said means configured for harvesting at least a portion of a tree and/or said UAV. The invention also relates to a method for remotely and/or autonomously harvesting a tree

Description

METHOD AND SYSTEM FOR REMOTE OR AUTONOMOUS TREE HARVESTING Technical field of the lnvention The present invention relates in general to the field of tree harvesting and in particular tomethods and systems for remote and/or autonomous tree harvesting by means of at least one Unmanned Aerial Vehicle, UAV.

Background of the lnvention Traditional tree harvesting or tree falling has long been conducted by persons and equipmentbased on the ground. ln earlier times, from the early twentieth century and going back to theearly nineteenth century, little consideration was given to the state of the forest or to the eco-system within the forest. Logging was done on a massive scale to keep up with the demandcaused by the industrial revolution and the subsequent expansion of human life at the time.Depending on the terrain, tree harvesting process usually begins with experienced tree fellerscutting down a stand of trees or by using heavy ground based manned harvesting machines.

The above-described methods represent a high level of risk, either to the environment or thepeople performing the work. Damage can also be done to the delicate ecology of the forest,known as the understory or underbrush, where smaller plants bind the soil together and provide a habitat to insects, birds, lichens, and fungus among other things.

Most importantly, many locations are extremely difficult to reach by land, even with the use ofheavy equipment such as bulldozers, and removal of trees from such locations is expensive.Sometimes it may be desirable to harvest a single tree amongst a stand of trees, so called treethinning, without disturbing the surrounding trees. ln US 6,263,932 it is disclosed an aerial tree harvesting apparatus. A first body of said apparatus issuspended from helicopter and a second body is suspended by cables from the first body. Theapparatus is capable of delimbing and cutting the tree and thereafter transporting the harvestedtree to another location.

The problem with the tree harvesting apparatus in US 6,263,932 is that it is very expensive, slow, noisy and complicated to use.

Ob'|ect of the lnvention The present invention aims at obviating the aforementioned problem. A primary object of the present invention is to provide an improved system for harvesting trees.

Another object of the present invention is to provide an improved method for harvesting tfeeS.

Summary of the lnvention According to the invention at least the primary object is attained by means of the systemhaving the features defined in the independent claims.

Preferred embodiments of the present invention are further defined in the dependentclaims.

According to a first aspect of the present invention it is provided a system for remoteand/or autonomous harvesting at least a portion of a tree, said system comprising: a remotelyand/or autonomously controlled means configured for harvesting at least a portion of a tree, anda remotely and/or autonomously controlled Unmanned Aerial Vehicle comprising, at least onemeans for holding said harvested portion of said tree and being configured for transporting awaysaid harvested portion of said tree, wherein said system comprising at least one means fordetecting said tree to be harvested, and a base station for communication with said meansconfigured for harvesting at least a portion of a tree and/or said UAV.

An advantage of this embodiment is that the harvesting and transportation of harvestedtrees can be made from a remote location.

Another advantage of the present invention is that it may have none or at least very littleimpact on the nature other than the harvested trees itself.

Still another advantage of the present invention is that harvesting of a particular area maybe faster, easier to use, less complicated, less complex and more inexpensive compared to priorart.

Yet another advantage is that the present invention provides for an integrated solution forunmanned harvesting of trees. ln various example embodiments of the present invention said means configured forharvesting at least a portion of the tree is configured for moving up and down along a trunk of thetree.

An advantage of these embodiments is that said means do not need to be arranged directlyon the desired cutting position. Another advantage is that the means configured for cutting thetree trunk may be moved downwards along the trunk of the tree by using gravity. Yet anotheradvantage is that the tree may be cut in desired pieces without moving the tree from the original position. ln various example embodiments of the present invention said means configured forharvesting at least a portion of the tree is also configured for moving on ground.

An advantage of these embodiments is that said means may be delivered to the ground bysaid UAV at or near said tree to be harvested and/or said means may be delivered to the groundby said UAV or by a land vehicle at a distance from said tree to be harvested. Another advantageis that various types of trees may have said means attached on the tree to be harvested from aground position. ln various example embodiments of the present invention said UAV and said meansconfigured for harvesting at least a portion of the tree is communicating with each other via oneor more of WiFi, Bluetooth, radio communication, optical fibre and/or electrical wire.

An advantage of these embodiments is that the means configured for harvesting the treeand said UAV can be physically separated from each other.

Another advantage of these embodiments is that said means and said UAV may becontrolled individually independently of each other. Another advantage is that only the harvestedportion of tree may be transported away from the original position of the tree, i.e., lesstransportation weight compared to also transporting the means configured for harvesting thetree together with the harvested portion of the tree. ln various example embodiments of the present invention said means configured forharvesting at least a portion of the tree is connectable to an underside of said UAV. Furthermore,the UAV may be configured to be capable to precisely control position, velocity, orientation androtational speed and via a rigid connection impart its motion to the means for cutting as tofacilitate application to the tree top as well as cutting of the tree top limbs.

An advantage of these embodiments is that said UAV and said means for cutting the treetrunk may be attached and detached from each other. This may be advantageous in cases wherethe means for cutting said tree trunk must be delivered by said UAV or in other cases where saidmeans for cutting said tree is first delivered by a land vehicle and thereafter removed by said UAVafter finished harvesting. ln various example embodiments of the present invention said means configured forharvesting at least a portion of the tree is transported on ground to the tree to be harvested.

An advantage of these embodiments is that said means configured for cutting said treetrunk at a first instance may be delivered either at ground at or near a tree to be harvested by aland vehicle or the UAV. When said tree has been harvested said means configured for cuttingsaid tree trunk may of its own motion be transported to the next tree to be harvested while saidUAV is transporting the harvested tree to another location. This may increase the efficiency of the harvesting. ln various example embodiments of the present invention said UAV comprises a power unitfor powering said UAV and said means configured for harvesting at least a portion of said tree.

An advantage of these embodiments is that one and the same power unit may be shared bythe UAV and the means configured for harvesting at least a portion of said tree. ln various example embodiments of the present invention said UAV comprising a firstpower unit for powering said UAV and said means configured for cutting the tree trunkcomprising a second power unit for powering said means configured for cutting the tree trunk.

An advantage of these embodiments is that said means configured for harvesting at least aportion of the tree and said UAV may be operated physically separated and completelyindependently of each other. ln various example embodiments of the present invention said means configured forharvesting at least a portion of the tree is also configured for delimbing a tree.

An advantage of these embodiments is that said harvested tree or harvested portion of thetree may be removed to another location possibly without any further work before being putonto a truck, train and/or boat to a final destination. ln various example embodiments of the present invention said means configured forharvesting at least a portion of the tree is configured to be in direct communication with a remoteoperator and/or a remote base station or indirect communication via said UAV with a remoteoperator and/or a base station.

An advantage of these embodiments is that said UAV may or may not be a link in betweensaid base station or said operator. lt may be advantageous in some cases to send directinformation/instructions to the means configured for cutting said tree trunk when said UAV is faraway from said means configured for cutting said tree trunk. ln other circumstances it may beadvantageous to have the same information sent to both UAV and said means configured forcutting said tree trunk for synchronisation purposes. ln various example embodiment of the present invention it may comprise means configuredfor automatically locating a predetermined tree or a tree in a predetermined area to beharvested.

An advantage of these embodiments is that the tree localization may be performed fullyautomatic without the help of an operator. Such means may include one or more of a GNSSand/or a camera and/or optical sensor. Such means may also include machine learning/artificialintelligence in order to recognise a suitable tree and/or a suitable position of a tree to attach said means configured for cutting the tree trunk. ln various example embodiments of the present invention it may comprise asynchronization unit for synchronizing the movement of at least two UAV for transportation of atleast a portion of a harvested tree.

An advantage of these embodiments is that a plurality of UAV may be used in synchronismwith each other for transporting heavy trees/trunks or portions thereof and that it is moreefficient, less expensive and easier to use. The synchronisation unit may either be arranged in oneof the UAV being a master UAV for the other slave UAV or in a remote control unit forsynchronising all UAV at a remote distance. ln another aspect of the present invention it is provided a method for remotely and/orautonomously harvesting a tree, said method comprising the steps of: a. remotely and/or autonomously controlling a means configured for harvesting atleast a portion of a tree, b. a remotely and/or autonomously controlled Unmanned Aerial Vehicle, UAV, c. identifying a tree to be harvested, d. remotely and/or autonomously operating said means configured for harvestingsaid at least a portion of said tree, e. remotely and/or autonomously operating at least one means for holding said atleast a portion of said tree, where said at least one means for holding said at leasta portion of said tree is attached to said UAV, f. carrying said at least a portion of said tree, by said UAV, to another location.

The advantage of these embodiments is that the harvesting and transportation of harvestedtrees can be made from a remote location.

Further advantages with and features of the invention will be apparent from the following detailed description of preferred embodiments.

Brief description of the drawings A more complete understanding of the abovementioned and other features and advantagesof the present invention will be apparent from the following detailed description of preferredembodiments in conjunction with the appended drawings, wherein: Fig. 1-4 depict schematic pictures of different inventive remote and/or autonomous harvesting steps by using a system according to the present invention, and Fig. 5 depicts an example embodiment of a unit comprising a remotely and/orautonomously controlled means configured for harvesting at least a portion of a tree and at least one means for gripping said tree trunk Detailed description of preferred embodiments of the invention Figure 1-4 depict schematic pictures of different inventive remote and/or autonomous harvestingsteps of at least a portion of a tree by using an example embodiment of a system 10 according tothe present invention. Said system may comprise a remotely and/or autonomously controlledmeans configured for harvesting at least a portion of a tree 110, a remotely and/or autonomouslycontrolled Unmanned Aerial Vehicle 100, UAV, comprising, at least one means for holding 105said tree trunk and being configured for transporting said harvested portion of said tree toanother location, wherein said system comprising at least one means for detecting said tree to beharvested, and a base station 120 for controlling said means configured for harvesting at least a portion of a tree and said UAV. ln figure 1 said UAV 100 is carrying said remotely and/or autonomously controlled meansconfigured for harvesting at least a portion of a tree 110 on its way to harvest a tree 135 in aforest 130. The UAV is remotely controlled by said base station 120 and/or autonomously controlled and optionally communicating with base station 120. ln figure 1-4 the UAV can be considered as a forestry forwarder and said means configured for harvesting at least a portion of a tree can be considered to be a forestry harvester. ln an autonomously controlled means configured for harvesting at least a portion of a tree saidmeans is able to operate without being controlled directly by humans whereas in a remotelycontrolled means configured for harvesting at least a portion of a tree said means is able to beoperated from a remote distance controlled directly by humans. ln various example embodimentsaid means configured for harvesting at least a portion of a tree and said UAV are remotelycontrolled. ln various example embodiment said means configured for harvesting at least aportion of a tree and said UAV are autonomously controlled. ln various example embodimentssaid means configured for harvesting at least a portion of a tree is remotely controlled and said UAV is autonomously controlled. ln various example embodiments said means configured for harvesting at least a portion of a tree is autonomously controlled and said UAV is remotely controlled.

Said means for detecting a tree may be at least one of a camera or an optical sensor. The cameramay be at least one of for example an iR-carnera (ânfrared-canwera), NiRæanﬁera (Påear Enfrarerl~carnera), a VESP-åißcarnera (Visual iïšear infrared-carnera), a CCD canﬁera (Charged Coupied Üevice~carraera), a CEX/ïíšßcaanera (Compåeanentary Fwfietaä Oxide Seinšcondifctorcarneraﬁi, a digital canﬁera,a 3D camera e.g., stereo camera, time-of-flight camera or LiDAR. The optical sensor may at least one of a photodetector, pyrometer, proximity detector and/or an infrared sensor.

Said means for detecting a tree may be arranged on said UAV and/or said means configured for harvesting at least a portion of a tree.

The UAV may have one or a plurality of propellers. ln figure 1-5 said UAV has 6 propellers arranged symmetrically around an origin.

The base station 120 may, when remotely controlled, be operated by at least one human being,whereas, when autonomously controlled, be a base station 120 with programmed softwarealgorithms used for supporting the autonomous UAV and/or the means configured for harvesting at least a portion of a tree.

Said means for holding the said tree may be at least one movable gripping arm. ln variousexample embodiments said means for holding said tree may be one or a plurality of metal barswhich may at least partially penetrate a tree trunk. ln various example embodiments said meansfor holding said tree may be a unit surrounding said tree trunk and being able to change itsholding area and thereby compress around the tree trunk for securing purpose and decompress for releasing a tree trunk or entering a tree to be harvested. ln various example embodiments said means configured for harvesting at least a portion of thetree may be arranged with means for attaching itself to said tree trunk. ln various exampleembodiments said means configured for harvesting at least a portion of a tree is also configuredfor moving up and down along the trunk of the tree. The movement may be performed by at leastone electrically driven wheel travelling on said tree trunk. ln various example embodiments atleast one wheel may be electrically driven for enabling movement up and down said tree trunk and at least one other wheel is arranged for friction reduction during said movement. ln various example embodiments at least to wheels are configured to attach, secure and move said means configured to harvesting at least a portion of a tree. ln various example embodiments said means configured for harvesting at least a portion of thetree is also configured for moving on ground. The movement can be made via a plurality of wheels or legs and/or as a tracked vehicle.

Said UAV and said means configured for harvesting at least a portion of the tree may becommunicating with each other via one or more of WiFi, Bluetooth, radio communication,telecommunication (3G, 4G, 5G), optical fibre and/or electrical wire. ln various exampleembodiments said control unit and said UAV and/or said means configured for harvesting at leasta portion of the tree may be communicating with each other via one or more of WiFi, Bluetooth,radio communication, telecommunication (3G, 4G, 5G). Depending on the distance and/orcommunication quality between the control unit and said UAV and/or said means configured forharvesting at least a portion of a tree the communication may change from one type of communication to another. ln various example embodiments said means configured for harvesting at least a portion of thetree is connectable to an underside of said UAV. ln various example embodiments said meansconfigured for harvesting at least a portion of the tree may be released from said UAV directlyonto a tree to be harvested or on the ground at or near the tree to be harvested. ln variousexample embodiments said means configured for harvesting at least a portion of the tree may beprovided at a distance from said tree to be harvested from a land vehicle. The means configuredfor harvesting at least a portion of the tree may of its own motion move from the position onground to the desired tree to be harvested. Communication between said UAV and said meansconfigured for harvesting at least a portion of a tree may at any desired time result is a pick-up ofsaid means configured for harvesting at least a portion of a tree by said UAV. The pickup of saidmeans configured for harvesting at least a portion of a tree by said UAV may be made on ground if there is enough space or on a trunk of a tree. ln various example embodiments the UAV may comprise a power unit for powering said UAV andsaid means configured for harvesting at least a portion of said tree .The power from said powerunit in said UAV may be delivered to said means configured for harvesting at least a portion ofsaid tree via at least one power cable. The power unit may be an electric motor and/or an internal combustion engine. ln various example embodiments said UAV may comprising at least a first power unit for poweringsaid UAV and said means configured for harvesting at least a portion of the tree may comprise atleast a second power unit for powering said means configured for harvesting at least a portion ofthe tree .The power unit is said UAV may be electrical and/or an internal combustion engine. Thepower unit is said means configured for harvesting at least a portion of a tree may be electrical and/or an internal combustion engine. ln various example embodiments said means configured for harvesting at least a portion of thetree is also configured for delimbing a tree. The delimbing may be performed from top to bottomif said means configured for harvesting at least a portion of the tree is initially arranged on saidtree to be harvested from above. ln various example embodiments said delimbing may beperformed from bottom to the top if said means configured for harvesting at least a portion of atree is moved by its own motion from ground to the tree to be harvested or attached to a lowersection of the tree to be harvested from the UAV. The delimbing may be performed by one or aplurality of cutting means, snapping means, and/or shearing means. The cutting means may be bycutting chains and/or by rotary cutting disks. The cutting may be performed by a straightmovement along said trunk of said means configured for harvesting at least a portion of a treeand/or by a serpentine movement along the trunk by said means configured for harvesting atleast a portion of a tree. ln various example embodiments said means configured for harvesting at least a portion of thetree is configured to be in direct communication with a remote operator and/or a remote basestation 120 or indirect communication via said UAV with a remote operator and/or a base station120. The indirect communication, i.e., the UAV as access point, with said means configured forharvesting at least a portion of a tree may be used if the same information is to be sent to bothUAV and said means configured for harvesting at least a portion of a tree. The UAV may be invarious example embodiments work independently from a remote base station 120. The indirectcommunication may also be used if said UAV is arranged in between said base station 120 and said means configured for harvesting at least a portion of a tree. ln various example embodiments said UAV and/or said means configured for harvesting at least aportion of a tree may comprise means configured for automatically locating a tree and/or apredetermined area to be harvested. Said means configured for automatically locating a treeand/or said predetermined area to be harvested may comprise at least a Global Navigation Satellite System, GNSS. Said means configured for automatically locating a tree and/or a predetermined area to be harvested may comprise at least one camera or optical sensor. Saidmeans configured for automatically locating a tree and/or a predetermined area to be harvestedmay comprise at least a camera in combination with Artificial intelligence or machine learningalgorithms for speeding up the detection of a suitable area to arrange said means configured to cut a tree trunk.

Now returning to figure 1 where the UAV 100 is on its way to a tree 135 in forest 130 to beharvested. The tree 135 may be preselected, i.e., selected prior to arrival to the tree 135.Alternatively said tree 135 may be selected by the UAV 100 in combination with the base station120 once the UAV 100 is at or near a position above said tree 135. The selection may beperformed by identifying a picture of the tree 135 from above with stored pictures in said controlstation 120 and by means of a selection algorithm select a tree for tree thinning purpose or other selection criteria. ln figure 2 the selected tree 135 has been attached on its top portion by at least one means forgripping 105 said tree trunk. A gripping position on said tree 135 may be selected depending onthe expected lift weight of the harvested portion of said tree. lf the full tree is to be harvested agreater diameter of said trunk of the tree is to be chosen as a gripping position compared to if just a portion of the tree is to be harvested. ln figure 3 the autonomously controlled means configured for harvesting at least a portion of atree 110 has been moved a distance down from said at least one means for gripping 105 said treetrunk. On its way down said means configured for harvesting at least a portion of a tree 110 alsohas delimbed the tree 135 leaving a bare tree trunk 137 without twigs and limbs. The powering ofsaid means configured for harvesting at least a portion of a tree 110 may be provided by said UAV100 or by a power unit in said means configured for harvesting at least a portion of a tree 110. lncase of power supplied from said UAV to said means configured for harvesting at least a portionof a tree 110 said power may be delivered via one or a plurality of power cables arranged onbetween said UAV 100 and said means configured for harvesting at least a portion of a tree 110. Apower unit in said means for cutting a tree trunk 110 may be one or a plurality of battery packs. lnvarious example embodiments a first battery pack maybe used for communication with the UAV100 and/or a base station 120. A second battery pack may be used for moving said means forharvesting at least a portion of a tree 110 up/down on a tree trunk and/or for moving said means for harvesting at least a portion of said tree 110 on ground. ln figure 4 the tree 135 has been delimbed, harvested and on its way to a location away from theoriginal location of the tree. What is left of the original tree 135 at its original location is apile of limbs 138 and a tree stunip 139. In the depicted example embodiment said meansconfigured for harvesting at least a portion of a tree 110 is still arranged on said tree trunk when the tree is transported away from the original location of the tree. lnstead of as in figure 4 delimbing and cutting the full tree, said tree may be harvested in sectionsstarting from above and going down the trunk of the tree. When a section of the tree has beenharvested, said means configured for harvesting at least a portion of a tree 110 may be left on thestill uncut portion, the stump, of the tree while the UAV is transporting away the harvested portion fron1 the original location of the tree.

Delimbing means may be arranged on a top portion and on a bottom portion of said meansconfigured for harvesting at least a portion of a tree 110. By arranging said delimbing means onboth sides of said means configured for harvesting at least a portion of a tree 110 makes itpossible to provide said means configured for harvesting at least a portion of a tree 110 fromabove on the tree or from root of said tree. The delimbing means is provided at the front positionwith respect of the direction of movement of said means configured for harvesting at least a portion of a tree 110. ln various example embodiments said means configured for harvesting at least a portion of a tree110 may be provided by said UAV directly on a portion of the tree to be harvested where there are no limbs. ln various example embodiments said means configured for harvesting at least a portion of a tree 110 may be dropped on the ground at or near the tree to be harvested. ln figure 5 it is depicted a schematic picture of an example embodiment of said means configuredfor harvesting at least a portion of a tree 110 and said means for holding said tree 105. Saidholding means 105 may be provided at a distance from said UAV 100, for instance via one or aplurality of wires 111a. The holding means 105 is in this example embodiment in the form of afirst movable curved arm 107a and a second movable curved arm 107b. Said arms (107a, 107b)can be set to any position between a fully open position and fully closed position in order to allow to embrace a tree trunk and also to grip and release the same. Said means configured for harvesting at least a portion of a tree 110 comprises in figure 5 a first movable curvedfixing/delimbing arm 114a and a second movable curved fixing/delimbing arm 114b. Said first andsecond movable curved fixing/delimbing arms (114a, 114b) may be set to any position between afully open position and fully closed position on order to allow to embrace a tree trunk and also tofixing the same. Said fixing/delimbing arms may have a sharp edge on its top portion and/or itsbottom portion for delimbing the tree as the means configured for harvesting at least a portion ofthe tree moves along the trunk of said tree. Said means configured for harvesting at least aportion of a tree 110 also comprises a cutter 116. The cutter may be in the form of an electricallydriven or internal combustion engine driven chain saw. The chain saw may be arranged movablein said means 110 in order to cut a tree while said means is in a fixed position on said trunk of the tree.

The delimbing means 114a, 114b may be optional. The holding means 105 may be provided at adistance from said means configured for harvesting at least a portion of a tree 110. Said holdingmeans 105 may be attached at said means configured for harvesting at least a portion of a tree110 with at least one wire 111b or at least one metal bar or other suitable attaching means. lnvarious example embodiments said holding means 105 may be mechanically separable from saidmeans configured for harvesting at least a portion of a tree 110 meaning that the holding meansmay attached at a fixed position at the tree while the means configured for harvesting at least aportion of the tree may of its own motion move along the trunk of the tree with no mechanicalattachment to the holding means 105. The means for harvesting at least a portion of a tree maycut a portion of a tree and stay on the still not harvested portion of the tree while said UAV ismoving away with the harvested portion to another location. Delimbing may take place by saidmeans configured for harvesting at least a portion of a tree 110 while said UAV is moving awaysaid harvested portion of the tree. The UAV may return to the same tree and remove yet anotherportion of it and said means configured for harvesting may stay on the not yet harvested portionor attach to the harvested portion or the UAV and move together with the UAV to anotherlocation. The holding means 105 and the means configured for harvesting at least a portion of atree 110 may communicate with each other and/or independently of each other communicatewith the UAV and/or the base station 120. A camera may be used, attached either on said UAV orsaid may be used for means configured for harvesting at least a portion of a tree 110, in order tosimplify attachment of said UAV with said means configured for harvesting at least a portion of atree 110. The attachment of said UAV and said means configured for harvesting at least a portionof a tree 110 may be a fully automatic process. Said means configured for harvesting at least a portion of a tree 110 may have at least one electrically driven wheel 190 for allowing movement of said means configured for harvesting at least a portion of a tree 110 along a trunk of a tree.One or a plurality of supporting wheels 112 may be used for securing said means configured forharvesting at least a portion of a tree 110 onto said trunk of said tree and for reduce friction whilemoving along said trunk of said tree. Said supporting wheel(s) may be arranged on arms 188which may be movable in order to secure said means configured for harvesting at least a portion of a tree 110 on said trunk of said tree. ln various example embodiments said means configured for harvesting at least a portion of a tree110 may be made of two separable parts, a first part that is mainly configured for holding the treeand a second part, capable of moving up and down along the trunk of the tree, which can delimb and/or cut the tree. ln various example embodiments said means configured for harvesting at least a portion of a tree110 may be provided at or near the tree to be harvested either by the UAV or by a land vehicle.Said means configured for harvesting at least a portion of a tree 110 may of its own motion movetowards a predetermined tree to be harvested and arrange itself at a predetermined position onthe trunk. An UAV may before said tree is cut be arranged at a top position of said tree and gripthe trunk of the tree on a position safe to lift the portion to be cut. Said means configured forharvesting at least a portion of a tree 110 cuts the tree and the UAV moves the harvested treeaway from the original location ofthe tree. The harvested tree has all of its limbs left on thetree. Said means configured for harvesting at least a portion of a tree 110 may follow the harvested tree from the original location of the tree or stay at the tree stump. ln various example embodiments said means configured for harvesting at least a portion of a tree110 may be provided at or near the tree to be harvested either by the UAV or by a land vehicle.Said means configured for harvesting at least a portion of a tree 110 may of its own motion movetowards a predetermined tree to be harvested and arrange itself at a predetermined position onthe trunk. An UAV may, before said tree is cut, be arranged at a top position of said tree andhold/grip the trunk of the tree on a position safe to lift the portion to be cut. Said meansconfigured for harvesting at least a portion of a tree 110 first moves upwards the trunk of the treein order to delimb the same. Thereafter said means configured for harvesting at least a portion ofa tree 110 moves to a predetermined position and cuts the tree. The UAV moves the harvested tree from the original location ofthe tree. The harvested tree is delimbed. Said means configured for harvesting at least a portion of a tree 110 may follow the harvested tree from the original location of the tree or stay at the tree sturnp.

The system may comprise a plurality of UAV and a plurality of means configured for harvesting at least a portion of a tree all of which may work together for efficiently harvesting trees in a forest.

A plurality of UAV may work together synchronously for transporting a harvested portion of atree. This may be arranged so that a first UAV is a master UAV and at least a second UAV is a slaveUAV. The master UAV may grip the tree to be harvested at a predetermined position on its trunk.Said at least one slave UAV may be attached to said master drones via wires. Said at least oneslave UAV may be arranged at an elevated position with respect to the master UAV. Asynchronisation unit makes sure the master UAV and the at least one slave UAV works insynchronisation with respect to movement and distance to each other. The synchronisation unitmay be arranged in the master UAV or arranged in the control unit controlling said master UAV and said at least one slave UAV. |nstead of a single UAV gripping said portion of the tree to harvest a plurality of UAVs may grip the same tree to be harvested. ln various example embodiments of the present invention said UAV is designed to be capable offlying as to control position, velocity, orientation and rotational speed and via a rigid connectionimpart its motion to the means for cutting/delimbing said tree. ln this embodiment the UAV controls the movement of the means for cutting/delimbing said tree. ln various example embodiments of the present invention the UAV may be used to reduce loadon said cutting means 116 during cutting. This may be performed by first holding a predeterminedportion of the tree by said holding means 105 and thereafter apply a lift force by said UAV whilecutting the tree by the means for harvesting at least a portion of the tree 110. This may beadvantageous since a reduced load on the cutting means 116 from the weight of the tree mayincrease the efficiency of the cutting procedure and/or require less power compared to cutting a tree with the full load onto said cutting means 116. ln various example embodiments a separate land vehicle may be used with means for harvestingat least a portion of said tree while the UAV is lifting the tree. This may be advantageous since there is no load on the cutting means from the weight of the tree which may increase the efficiency of the cutting procedure and/or require less power compared to cutting a tree with the full load of the portion to be cut on said cutting means. ln various example embodiments the UAV is configured with aerodynamic means, comprisingrotors, fans, wings, or equivalent combination, interacting with the air so as to be capable to precisely control the UAV position, velocity, orientation and/or angular velocity. ln various example embodiments said UAV and said means configured for harvesting at least aportion of a tree may be separated from each other end reconnected with each other. One or aplurality of cameras or other suitable position sensors may be used for the reconnection procedure.

The means configured for harvesting at least a portion of a tree may optionally be capable for moving on ground. The movement may be with legs, wheels or other suitable moving means. ln various example embodiments of the present invention a digital transmitter may be attachedto a tree for communication with a control unit and/or at least one UAV and/or at least onemeans for harvesting at least a portion of a tree . Said digital transmitter may not only send outthe position of said tree it is attached to but also send out information about distance toneighbour trees, the terrain, the diameter of the tree, the final destination of a non-harvestedtree and/or other quality parameters of the tree such as type and/or curved trunk. The digitaltransmitter may be attached to the tree by a UAV, land vehicle, robot or by a human. The digitaltransmitter function may also be implemented as a pure software digital recognition function byunique features of the tree such as tree rings, limb pattern or tree bark.

The digital transmitter may be used to determine which tree to be harvested, where to move theharvested tree in order to simplify transportation logistics. A digital transmitter may be used tomove trees/timber of different quality to different locations by said UAV. A digital marking may beused to determine which drone and/or means for harvesting at least a portion of a tree trunk tobe used. The digital information may be used for using one or a plurality of UAV depending on thesize of the tree to be harvested. The digital marking may be used for tree thinning. The digitalmarking may be used in combination with a remote harvesting planning and/or tree thinningprocess prior to the actual harvesting. With digital marking a map of trees in a predeterminedarea may be used for guiding the UAV to the correct tree to be harvested. The digital marking mayalso determine in which order the trees shall be harvested in order to reduce the harvesting time.

The digital marking may be used to estimate a future harvesting time. The digital marking may be used to determine which type of trees there are in a particular area, the distance between treesin a particular area, the topography of the land where trees are to be harvested, the height of thetree, the quality of the tree, the form of the tree, the diameter of the tree. The digital markingmay determine prior to harvesting of the tree shall be cut in portions. The digital marking may be used to mark the different portion of the harvested trees weight.

Feasible modifications of the lnvention The invention is not limited only to the embodiments described above and shown in thedrawings, which primarily have an illustrative and exemplifying purpose. This patent application isintended to cover all adjustments and variants of the preferred embodiments described herein,thus the present invention is defined by the wording of the appended claims and the equivalentsthereof. Thus, the equipment may be modified in all kinds of ways within the scope of theappended claims.

Harvesting means falling of trees and prepariiwg them for transport away from its originallocation. lt includes both thinning and clearfeiiing operations.

For instance the disclosed system may also transport already harvested trees or portions oftrees laying on ground.

Throughout this specification and the claims which follows, unless the context requiresotherwise, the word "comprise", and variations such as "comprises" or "comprising", will beunderstood to imply the inclusion of a stated integer or steps or group of integers or steps but not the exclusion of any other integer or step or group of integers or steps.

Claims

1. 1. A system (10) for remote and/or autonomous harvesting at least a portion of a tree, said system (10) comprising: a. a remotely and/or autonomously controlled means (110) configured forharvesting said at least a portion of a tree, b. a remotely and/or autonomously controlled Unmanned Aerial Vehicle (100), UAV,comprising, at least one means for holding (105) said harvested portion of saidtree and being configured for transporting said harvested portion of said treeaway from the original location of the tree, wherein said system comprising atleast one means for detecting said tree to be harvested, and c. a base station (120) for communication with said means configured for harvesting at least a portion of a tree and/or said UAV.

2. The system according to claim 1, wherein said means configured for harvesting at least a portion of the tree is configured for moving up and down along a trunk of the tree.

3. The system according to any one of claim 1-2, wherein said means configured for harvesting at least a portion of the tree is also configured for moving on ground.

4. The system according to any one of claim 1-3, wherein said UAV and said meansconfigured for harvesting at least a portion of the tree is communicating with each othervia one or more of Wifi, Bluetooth, radio communication, optical fibre and/or electrical wire.

5. The system according to any one of claim 1-4, wherein said means configured for harvesting at least a portion of the tree is connectable to an underside of said UAV.

6. The system according to any one of claim 1-4, wherein said means configured forharvesting at least apportion of the tree is transported on ground to the tree to be harvested.

7. The system according to any one of claim 1-5, wherein said UAV comprises a power unit for powering said UAV and said means configured for harvesting at a portion of said tree.

8. The system according to claim 7, wherein the power from said power unit in said UAV isdelivered to said means configured for harvesting at least a portion of said tree via at least one power cable.

9. The system according to any one of claim 1-8, wherein said UAV comprising a first powerunit for powering said UAV and said means configured for harvesting at least a portion ofthe tree comprising a second power unit for powering said means configured for harvesting at least a portion of the tree.

10. The system according to any one of claim 1-9, wherein said means configured forharvesting at least a portion of the tree is also configured for delimbing at least a portion of said tree.

11. The system according to any one of the preceding claims, wherein said means configuredfor harvesting at least a portion of the tree is configured to be in direct communicationwith a remote operator and/or a remote base station (120) or indirect communication via said UAV with a remote operator and/or a base station (120).

12. The system according to any one of the preceding claims, further comprising means configured for automatically locating a tree in a predetermined area to be harvested.

13. The system according to claim 12, wherein said means configured for automaticallylocating a tree in a predetermined area to be harvested comprising at least a GlobalNavigation Satellite System, GNSS or a digital transmitter configured to be attached to a tree and to communicate with the UAV.

14. The system according to any one of the preceding claims, further comprising asynchronization unit for synchronizing the movement of at least two UAV for transportation of at least a portion of a harvested tree.

15. A method for remotely and/or autonomously harvesting a tree, said method comprising the steps of: a. remotely and/or autonomously controlling a means configured for harvesting at least a portion of a tree, b. a remotely and/or autonomously controlling Unmanned Aerial Vehicle, UAV, c. identifying a tree to be harvested, d. remotely and/or autonomously operating said means configured for harvestingsaid at least a portion of said tree, e. remotely and/or autonomously operating at least one means for holding said atleast a portion of said tree, where said at least one means for holding said at leasta portion of said tree is attached to said UAV, f. transporting said at least a portion of said tree, by said UAV, away from the original location of the tree.

16. The method according to claim 15, further comprising the step of:g. moving said means configured for harvesting said at least a portion of said tree up and/or down along a trunk of said tree.

17. The method according to claim 15 or 16, further comprising the step of:h. moving said means configured for harvesting said at least a portion of said tree on ground in a direction to and/or from said tree to be harvested.

18. The method according to any one of claim 15-17, further comprising the step of:i. powering said means configured for harvesting said at least a portion of said tree from a power unit arranged in said UAV.

19. The method according to any one of claim 15-17, further comprising the step of:j. powering said means configured for harvesting said at least a portion of said treefrom a power unit arranged in said means configured for harvesting said at least a portion of said tree.

20. The method according to any one of claim 15-19, further comprising the step of:k. setting up a communication link between said UAV and said means for harvestingsaid at least a portion of said tree via one or more of WiFi, Bluetooth, radio communication, tele communication, optical fibre and/or electrical wire.

21. The method according to any one of claim 15-20, further comprising the step of:l. delimbing at least a portion of said tree to be harvested with said means for harvesting said at least a portion of said tree.

22. The method according to claim any one of claim 15-21, further comprising the step of:m. separating said UAV from said means configured for harvesting said at least aportion of said tree or reconnecting said UAV to said means configured for harvesting at least a portion of said tree.

23. The method according to any one of claim 15-22, further comprising the step of:n. carrying said at least a portion of said tree away from the original location of thetree by said UAV while said means configured for harvesting at least a portion of said tree is attached to said portion of said tree being carried.

24. The method according to any one of claim 15-22, further comprising the step of:o. carrying said at least a portion of said tree away from the original location of thetree by said UAV while said means configured for harvesting at least a portion of said tree is secured to the tree yet to be harvested.

25. The method according to any one of claim 15-24, further comprising the step of:p. setting up a direct remote communication between at least one operator andsaid means configured for harvesting at least a portion of the tree or an indirectremote communication via said UAV with said at least one operator and said means configured for harvesting at least a portion of the tree.

26. The method according to any one of claim 15-24, further comprising the step of:q. setting up a direct autonomous communication between at least one base stationand said means configured for harvesting at least apportion of the tree or an indirectautonomous communication via said UAV with said at least one base station and said means configured for harvesting at least a portion of the tree .

27. The method according to any one of claim 15-26, further comprising the steps of: r. identifying a first predetermined area within which a tree is to be harvested and/or a tree to be harvested by means of a GNSS-system by means of at least one of a camera and/or at least one optical sensor.

28. The method according to any one of claims 15-27, further comprising the step of: s. synchronizing a movement of at least two UAV for transportation of at least a portion of a harvested tree away from the original location of the tree.

29. An Unmanned Aerial Vehicle, UAV, configured to be used in a system according to any 5 one of claim 1-14.

30. The UAV according to claim 29, further comprising a synchronization unit for synchronizing the movement of at least two UAV. 10

31. A means configured for harvesting at least a portion of a tree configured to be used in a system according to any one of claim 1-14.