Patent Application
20180160634
A. Technical Field
The present invention generally relates to the technical field of mechanical thinning in agriculture, and more specifically mechanical thinning of grape vine shoots.
B. Description of Related Art
In Viticulture, grape vines often have a high vigor growth, leading to either a high-density canopy throughout the vine, or un-balanced growth throughout the vine. Depending on varietal and farming technique, it is often necessary to remove many shoots throughout the entire vine canopy, or in certain higher density shoot number areas. This removal of canopy shoots is referred to as shoot thinning, and usually takes place during the beginning months of the growing season. Shoot thinning is often performed in order to conform a vine to a desired uniform spacing for maximum fruit quality. In one example, farmers and hand crews, thin the crops by hand. Cost of hand thinning is steadily increasing due to a multitude of factors. These factors comprise declining availability of laborers and increasing government minimum wage standards. As a result, reducing hand labor can increase savings for farmers and growers.
Therefore, there is a need in the art for a device and method of mechanically thinning grape vine shoots, as to save on labor costs, without under or over-thinning specific areas throughout the entire grape vine.
The present invention relates to a device and method for thinning grape vine shoots, which detects shoot size throughout the vine and adjusts the thinning accordingly.
The unique design of the present invention, a device for thinning grape vine shoots, comprises a Normalized Differential Vegetative Index (NDVI) sensor, a shoot-removal whip assembly, and a programmable logic controller or “PLC”. The shoot removal whip is configured to remove at least one grape vine shoot when activated. In short, the programmable logic controller controls the shoot removal whip assembly. Further, the programmable logic controller handles logic and processing of information with a pre-defined algorithm. The algorithm processes the input and output data, and constantly relays a command signal to a hydraulic valve controlling the shoot removal whip assembly. The hydraulic valve uses the command signal from the programmable logic controller to control hydraulic oil flow to the shoot removal whip assembly. The whipping assembly, therefore, removes a certain number of shoots, in relation to the relative density of the grape vine shoot count. The programmable logic controller (PLC) comprises a memory unit, and a processor, programmed with a pre-defined control algorithm. The PLC is a “real-time” system, which produces output results in response to input conditions. In one instance of the current invention, the input conditions is an NDVI value, ranging from 0.001 to 1.000 dimensionless units. This NDVI value is a measurement of the grape vine shoots currently being read by the NDVI sensor, as the thinning system makes its way down the vineyard rows. The PLC module processes the information regarding at least one grape vine shoot to generate a plurality of grape vine shoot parameters. An adjustable gain potentiometer, which allows the operator to adjust the shoot removal size threshold, inputs a value into the PLC algorithm. The control algorithm continually processes the real-time NDVI value. The PLC continually generates a command signal to the hydraulic control valve, which in turn eliminates either: no shoots, one shoot, or many shoots, in a specific area of the vine. The rotational speed of the shoot-removal whipping assembly can be varied by the hydraulic control valve from 0 rotations per second, upwards to 20 rotations per second. If commanded not to activate, i.e. the shoot length and density is not deemed needing thinning, the removing assembly will not remove any shoots. Furthermore, one unique, key aspect of the current invention is that short, low growth (density) areas of the vine are left untouched by the machine while high growth (density) areas are thinned appropriately; thus balancing the vine to a desirable condition.
In one embodiment of the present invention, information regarding the plurality of optimal grape vine shoot parameters comprises of at least one of: an optimal distance from adjacent grape vine shoots on a grape vine (density), an optimal length of the grape vine shoot, optimal position of the grape vine shoots. The combination of these parameters makes up the present referred to “canopy size”. In one example, the NDVI Sensor takes a reading of grape vine shoot size and density, and sends a number varying from 0.001 to 1.000 back to the programmable logic controller. The shoot count and size throughout a grape vine is key among the plurality of grape vine shoot parameters.
A description of embodiments of the present invention will now be given with reference to the Figures. It is expected that the present invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative and not restrictive.
The scope of the invention is, therefore, indicated by the appended claims rather than by the foregoing description. All changes that come within the meaning and range of equivalency of the claims are to be embraced within their scope.
The NDVI sensor 105 differentiates a growing shoot on the vine from old vine wood, soil, etc. The NVDI sensor 105 senses information regarding at least one grape vine shoot. Further, the NVDI sensor 105 transmits information regarding at least one grape vine shoot to the programmable logic controller 110. The programmable controller 110 sends a command to the proportional hydraulic valve 115; in this instance a voltage reading from 0 to 10 Volts. The proportional hydraulic valve 115 controls the hydraulic flow to the removal whip assembly 120, which in rotates and removes shoots. A block diagram of the programmable logic controller 110 is exemplarily illustrated in
Referring to
At step 310, the programmable logic controller receives information from the external gain potentiometer sensor, adjustable by the operator. The potentiometer varies a voltage resistance reading from the PLC, which allows the thinning rate to be decreased or increased relatively.
At step 315, the input module, executed by the processor, receives information regarding at least one grape vine shoot via the NDVI sensor. In one example, the NDVI Sensor takes a reading of grape vine shoot size, and sends a number varying from 0.00 to 0.99 back to the programmable logic controller.
At step 320, the processor compares the output value from the NDVI sensor, 0.00-0.99 to the optimal grape vine shoot parameters, modified by the gain potentiometer. The processor determines the output command value to send to the proportional hydraulic valve.
At step 325, the processor sends a command via the output bus module to the proportional hydraulic valve to adjust desired thinning rate determined by the PLC. In one instance, the output to the proportional valve varies from 1.0 to 10.0
At step 330, the shoot removal whip assembly, if activated via the PLC, receives hydraulic oil and removes the appropriate amount of shoots.
The method 300 ends at step 335. The process restarts and shoot removal constantly varies as the device moves down the vineyard row on a vehicle.
The foregoing description comprises illustrative embodiments of the present invention. Having thus described exemplary embodiments of the present invention, it should be noted by those skilled in the art that the within disclosures are exemplary only, and that various other alternatives, adaptations, and modifications may be made within the scope of the present invention. Merely listing or numbering the steps of a method in a certain order does not constitute any limitation on the order of the steps of that method. Many modifications and other embodiments of the invention will come to mind to one skilled in the art to which this invention pertains having the benefit of the teachings presented in the foregoing descriptions. Although specific terms may be employed herein, they are used only in generic and descriptive sense and not for purposes of limitation. Accordingly, the present invention is not limited to the specific embodiments illustrated herein.
