FI121726B - A method for controlling the harvester head - Google Patents

Description

METHOD FOR MONITORING THE HARVESTER FALLING HEAD

The invention relates to a method for controlling the harvester head.

Mechanical management of young forest and seedling has been the subject of lively research in recent years. The clearing work is largely man-made with clearing and motor-5 saws, but the work is heavy and productivity is relatively low in relation to cost. Mechanical clearing and grafting have proved to be effective especially in the treatment of mature seedlings and young tree nurseries. However, moving and using machines, and in particular felling and clearing implements, in a dense forest is associated with a high risk of damaging the trees left to grow. According to the 2008 Quality Inventory, up to 34% of the sites have been noticeable in a variety of 10 mechanical energy wood thinning, where the density of trees left in the forest is high due to their young age. The most common reasons for a note are excessive tree damage and a lower density than the recommended tree stock. For example, mechanical harvesting of the energy ring, where the density of the 15 stands to be left at about 1400 trunks per hectare, could result in harvest damage to about 9% of the trees grown. About 65% of these damages are caused by the boom or felling head, and about 30% by impact of the felling / pruning frame on the side of the tree to be grown as the tree protrudes from the felling head when pruning. This type of wood damage is expected to be more significant than the younger and more dense forests are mechanically harvested.

It is an object of the invention to provide a method for monitoring the harvester head which eliminates the above problems. In particular, it is an object of the invention to provide a method by which tree damage can be reduced by mechanical clearing and grafting of trees. It is a further object of the invention to provide a method for facilitating the operator to detect possible trees that are obstructing harvesting.

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The object of the invention is achieved by a method for controlling the harvester head, which is characterized by what is claimed.

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In the method according to the invention, one or more observers placed in the harvester and / or the harvester's tipping end o detect the direction of movement of the tapping head o w and monitor the harvest line. In this case, obstacles detected on the harvesting or clearing line and in its vicinity may be automatically taken into account in the movements of the tipping head 2 and / or the obstacles detected may be reported to the operator, who shall take them into account in his action.

In the method according to the invention, the detectors placed on the harvester's felling head can easily and reliably check the intended felling position and space of the felled / cleared / harvested frame at the beginning and during the felling / clearing / harvesting process. trees. In particular, the method of controlling the operation of the felling head in accordance with the invention facilitates the operator and helps him to detect possible saving trees that prevent the logging / clearing / harvesting. 10 The monitoring device does not significantly slow down the harvesting process and enables the reduction of tree damage especially in dense young regeneration forests.

In a preferred embodiment of the invention, the method detects the direction of movement of the tipping head stereoscopically with two cameras. Digital cameras offer a relatively inexpensive and technically reliable alternative for tracking the subject.

In another preferred embodiment of the invention, the method employs 3D measurement with a laser line.

In a third preferred embodiment of the invention, the method employs ultrasound technology. Ultrasonic sensors are simple and durable and inexpensive.

In the following, the invention will be explained in more detail with reference to the accompanying drawings, in which Figures 1a and Ib show a method for controlling the harvester head and an operating principle thereof,

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2- Figure 2 is a schematic view of an embodiment of the method employing stereoscopic imaging with two cameras;

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| Figures 3a and 3b are a schematic view of an application of the method employing 3D measurement using a laser line, and Figs. 4a and 4b show the measurement areas of the ultrasonic transducer at different sizes of tubes.

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The figures show the harvester head 1 and the stem tree 5 therein. In addition, the figures schematically show the sensing devices 2, 3 for detecting and tracking the direction of movement of the head.

The operating principle of the method of controlling the harvester feller head according to the invention is shown in Figures 1a and Ib. A camera, ultrasound or other observing device (s) (not shown in Figures 1a and Ib) attached to the felling head 1, checks or verifies the area of the harvested trunk 5 harvested from the felling head, dashed in Figures 1a and Ib, and informs the machine operator or any obstacles on the harvest line. In the case of Ku-10a, feeding, i.e. moving the tipping head, is permitted, since there is no obstacle on the berth line. In the case of Fig. Ib, the supply is blocked because the harvest line has an obstacle 4. The apparatus includes a data unit (not shown in the figures) placed on the tipping head or on the machine to which data is transmitted wirelessly or wired from the observer (s). The information unit shall have the necessary memory unit 15 and the data obtained from the observation equipment may be processed accordingly. The data processed from the information unit is transmitted to a landfill control unit and / or to a device in the vicinity of the machine operator, such as a display device. The display device is programmed to display to the driver the distances of obstructions detected and to indicate in some way, such as green light, the obstruction-free area 20 to which the tipping head can be moved or the tree pruned.

Figures 2-4b show three different techniques by which the method can be implemented.

Fig. 2 is a 3D representation based on a change in depth of field or stereoscopic imaging with two cameras 2, 3. The cameras are positioned at an angle to each other at the tilt structures and continuously monitor the area in front of the tipping head. The computer image processing in the data unit i o enables the identification of tree trunk patterns and the estimation of free space. It should be noted that in forest conditions, twigs and other low-light conditions set technical requirements for camera and lighting.

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g 30 Figures 3a and 3b show a 3D measurement using a laser line. As shown in Figure 3a, the laser light source 3 with line optics is positioned at an angle to the camera 2, whereby a line image (Figure 3b) reflected at different distances is reflected in the camera

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heights. Both devices are located at different locations in the dump head structures. Here you can identify the position of the target frames on the harvest line. The system employs a technology that allows laser light of sufficient intensity to be focused at a distance of 3-5 meters 4 from the tipping head and, on the other hand, the ability to adjust the camera's exposure technology. Still, image processing technology is used to identify the dashed outlines of trees.

In the following embodiment, the apparatus includes an ultrasonic sensor for transmitting an ult-5 audio pulse and receiving an echo. The preliminary study tested a 120 kHz audio frequency sensor with a relatively narrow beam. The test sensor detected a 25-130 mm diameter body in a 0.6-1.5 m wide sector 5 m from the sensor. Figure 4a shows the measurement result of an ultrasonic transducer from an object having a diameter of 130 mm. Figure 4b shows the measurement result of an ultrasonic transducer from an object 10 having a diameter of 25 mm. The sensor is capable of providing information on the target distance, allowing the operator to evaluate whether the detected target echo is significant or not. This is especially important in forested conditions, where insignificant echoes can occur, for example, in snowy branches. Ultrasound technology may be associated with false positive echoes, but a suitably spaced distance display 15 helps the driver quickly evaluate the significance of the echo finding. The information provided by the sensor is simple but sufficient for this purpose. The display device is programmed to display to the driver the distances of the detected echoes and, for example, to indicate a clear thinning area free of green light attached to the tipping head.

Other known techniques can also be used in detection equipment. The invention is not limited to the preferred embodiments shown, but may vary within the inventive idea of the claims.

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Claims (5)

A method for monitoring the harvester's felling head, characterized in that one or more observation devices (2, 3) disposed on the harvester and / or harvester's felling head (1) detect the direction of movement of the felling head and observe the harvest line 5; ) are automatically taken into account in the head movement and / or the operator is notified of any obstacles encountered. A method for controlling the harvester head in accordance with claim 1, characterized in that the method uses 3D imaging based on a change in depth of field 10. A method for controlling the harvester's felling head according to claim 1 or 2, characterized in that the movement direction of the felling head is stereoscopically detected by two cameras (2, 3). Method for monitoring harvester head 15 according to one of Claims 1 to 3, characterized in that the method employs a laser light source (3) and a camera receiver (2) and a 3D line by means of a laser line. A method for controlling the harvester head according to any one of claims 1 to 4, characterized in that the method employs ultrasonic technology. δ CM o oo CM X cc CL CM O 1 ^ LO 05 O O CM