BR102018069070B1 - ROW UNIT IN A PLANTING MACHINE, E, PLANTING MACHINE - Google Patents

Abstract

An agricultural planter row unit has a depth adjuster wheel supported by a depth adjuster wheel arm, to control planting depth. An actuator drives the movement of a mechanical stop that rests against a depth control wheel support arm to position the depth control wheel support arm to obtain a desired planting depth. A seed depth control system receives operator input from an operator compartment of a tow vehicle and automatically controls the actuation of the seed depth actuator.

Description

DESCRIPTION FIELD

[001] The present description refers to agricultural machinery. More specifically, the present description relates to adjusting a planting depth in a planter row unit.

FUNDAMENTALS

[002] There is a wide variety of different types of agricultural machinery. Some agricultural machines include planters that have row units. For example, a row unit is often mounted in a planter with a plurality of other row units. The planter is often towed by a tractor over the ground where seed is planted into the ground, using row units. The row units in the planter follow the soil profile through the use of a combination of a downward force assembly that communicates a downward force on the row unit to push disc openers into the soil and depth adjuster wheels to adjust the penetration depth of disc openers. Some current downforce assemblies provide a relatively fixed downforce. Some allow an operator to change the downward force applied to the row unit by adjusting a mechanical mechanism in the row unit, and others allow the operator to change the downward force from the operator compartment.

[003] In many current systems, the depth adjusting wheels are mounted to the row unit by one or more depth adjusting wheel arms. Adjusting the seed depth in the planter is done by stopping the planter, leaving the planter compartment and manually adjusting a depth adjustment arm stop to limit the movement of the depth adjustment wheel in relation to the disc opener. The manual adjustment mechanism often uses a spindle drive, a knob, or other mechanical mechanism that can be used to adjust the seed depth. This type of adjustment is a bit cumbersome and time-consuming. It also does not exactly lend itself to frequent changes, due to its cumbersome and time-consuming nature.

[004] Therefore, many planting operations are carried out with suboptimal planting seed depth settings. This may result in a loss of production potential. For example, at the beginning of a corn planting operation, the operator can set the seed depth to 3.08 cm (two inches) and then leave it at this depth until the corn planting operation is complete. The operator can leave it at this depth even though the depth may be suboptimal for varying environmental or soil characteristics.

[005] The above discussion is merely provided for general background information and is not intended to be used as an aid in determining the scope of the claimed matter.

SUMMARY

[006] An agricultural planter row unit has a depth regulating wheel supported by a depth regulating wheel arm, to control the planting depth. An actuator drives the movement of a mechanical stop that rests against a speed control wheel support arm to position the speed control wheel support arm to obtain a desired planting depth. A seed depth control system receives operator input from an operator compartment of a tow vehicle and automatically controls the actuation of the seed depth actuator.

[007] This summary is provided to introduce a selection of concepts in a simplified way, which will be described in more detail below in the detailed description. This summary is not intended to identify the principal features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter. The claimed subject matter is not limited to implementations that address any or all of the disadvantages noted in the pleas.

BRIEF DESCRIPTION OF THE DRAWINGS

[008] Figure 1 is a top view of an example of a planting machine.

[009] Figure 2 shows a side view of an example of a row unit of the planting machine illustrated in Figure 1.

[0010] Figure 3 shows an example of a planting depth actuator assembly.

[0011] Figure 4 shows the actuator assembly, illustrated in figure 3, in two different positions.

[0012] Figure 5 is a perspective view of an example of a portion of the actuator assembly illustrated in figures 3 and 4.

[0013] Figure 6 illustrates another example of a planting depth actuator set.

[0014] Figure 7 illustrates another example of a planting depth actuator set.

[0015] Figure 8 is a block diagram showing an example of a planting machine architecture.

[0016] Figure 9 is a block diagram showing an example of a planting depth control system in more detail.

[0017] Figures 10A and 10B (collectively referred to here as figure 10) show a flowchart illustrating an example of the operation of the planting depth control system shown in figure 9.

[0018] Figure 11 is a block diagram of an example of a planting depth calibration system in more detail.

[0019] Figures 12A-12C (hereinafter referred to as figure 12) are flowcharts illustrating an example of the operation of the planting depth calibration system in more detail.

[0020] Figures 13A-13D are schematic/symbolic illustrations showing the calibration steps.

[0021] Figure 14 is a block diagram of an example of a computing environment that can be used in the architectures shown in the previous figures.

DETAILED DESCRIPTION

[0022] Figure 1 is a top view of an example of an agricultural planting machine 100. The machine 100 is a row crop planting machine, which, illustratively, includes a tool bar 102 that is part of a frame 104. Figure 1 also shows that a plurality of planting row units 106 are mounted to the tool bar 102. The machine 100 can be towed behind another machine, such as a tractor.

[0023] Figure 2 is a side view showing an example of a row unit 106. The row unit 106 illustratively includes a chemical tank 110 and a seed storage tank 112. It also includes, illustratively, a disc opener 114, a set of depth adjusting wheels 116, and a set of closing wheels 118. Seeds from the tank 112 are gravity fed into a seed feeder 124. The seed feeder controls the rate at which seeds are dropped into a seed tube 120 or other seed delivery system, such as a brush belt, from the seed storage tank 112. The seeds may be sensed by a seed sensor. seed 122.

[0024] It should be noted that there are different types of seed dosers, and the one shown is shown by way of example only. For example, in one example, each row unit 106 does not need to have its own seed meterer. Instead, metering or other seed individualization or division techniques may be performed at a central location for groups of row units 106. The metering systems may include rotating discs, concave or basket-shaped rotary devices, between others. The seed delivery system may be a gravity drop system (such as that shown in Figure 2), in which seeds are dropped through the seed tube 120 and fall (by gravitational force) through the seed tube into from the seed pit. Other types of seed delivery systems are assistive systems, in which they do not simply rely on gravity to move the seed from the dosing system into the soil. Instead, such systems actively capture seeds from the seed feeder and physically move the seeds from the feeder to a lower opening, where they exit into the soil or pit.

[0025] A downforce actuator 126 is mounted to a coupling assembly 128 that couples the row unit 106 to the toolbar 102. The actuator 126 may be a hydraulic actuator, a pneumatic actuator, a spring-tensioned mechanical actuator, or a wide variety of other actuators. In the example shown in Figure 2, a rod 130 is coupled to a system of parallel links 132 and is used to exert an additional downward force (in the direction indicated by arrow 134) on the row unit 106. The total downward force (which includes the force indicated by arrow 134 exerted by actuator 126, plus the force due to gravity acting on row unit 106, and indicated by arrow 136) is deflected by upwardly directed forces acting on closing wheels 118 (from the ground 138 and indicated by arrow 140) and the double disc opener 114 (again from the ground 138 and indicated by arrow 142). The remaining force (the sum of the force vectors indicated by arrows 134 and 136, minus the force indicated by arrows 140 and 142) and the force on any other component engaging the ground in the row unit (not shown), is the differential force indicated by arrow 146. The differential force may also be referred to here as the downforce margin. The force indicated by arrow 146 acts on the depth gauge wheels 116. This load can be sensed by a depth gauge wheel load sensor, which can be positioned at any location on the row unit 106 where it can sense this load. It can also be placed where it cannot directly sense the load, but an indicative characteristic of this load. Sensing a load both directly and indirectly is contemplated here and will be referred to as sensing a force characteristic indicative of this load (or force). For example, it may be disposed near a set of depth gauge control arms (or depth gauge arm) 148 that movably support the depth gauge wheels 116 to the flank 152 and control a wheel offset. depth adjusters 116 and the discs on the double disc opener 114, to control the planting depth. The arms (or depth gauge wheel arms) 148, illustratively, are in contact with a mechanical stop (or arm contact member - or wedge) 150. The position of the mechanical stop 150 relative to the flank 152 can be adjusted by a planting depth actuator assembly 154. The control arms 148, illustratively, pivot about the pivot point 156 so that when the planting depth actuator assembly 154 acts to change the position of the mechanical stop 150, a relative position of depth adjusting wheels 116, relative to the double disc opener 114, changes to change the depth at which the seeds are planted. This is described in greater detail below.

[0026] In operation, the row unit 106 moves generally in the direction indicated by arrow 160. The double-disc opener 114 opens a furrow in the soil 138, and the depth of the furrow 162 is adjusted by the planting depth actuator assembly 154 , which itself controls the deviation between the lowermost parts of the depth regulating wheels 116 and the disc opener 114. Seeds are dropped, through the seed tube 120, into the furrow 162 and the closing wheels 118 close the soil .

[0027] In previous systems, to change the planting depth, the tow vehicle operator would disassemble the tow vehicle and operate a mechanical actuator that would adjust the position of the mechanical stop 150. This would be done at each row unit. According to one example, the actuator assembly 154 can be actuated automatically by a control system from the operator's compartment of the tow vehicle. It can be actuated based on an operator input detected through this control system, or it can be actuated automatically to automatically change the planting depth as the row unit 106 is towed through the field. In one example, and as described in greater detail below, it can be actuated to maintain a desired hole contour or hole profile so that the depth of the seed hole varies in a desired manner.

[0028] Figure 3 shows an example of the planting depth actuator assembly 154, in more detail. Planting depth actuator assembly 154, illustratively, includes an actuator 190 that drives the rotation of a linkage system that, itself, drives the movement of the mechanical stop 150. In one example, the linkage system may include a mechanism for drive 180 that can be coupled to the action output 190. The drive mechanism 180, in turn, drives the movement of a mechanical stop or wedge 150, as described in more detail below. Because Figure 3 is a side view, only an opening disc 114, depth adjusting wheel 116, closing disk 118 and depth adjusting wheel arm 148 are shown. It will be appreciated, however, that each of these may have another member to form a pair. This is just an example. Items similar to those shown in figure 2 are similarly enumerated.

[0029] Figure 3 shows that disc opener discs 114 are rotatably mounted to flank 152 at point 173, are pulled through the soil in the direction indicated by arrow 160 and they open a pit or groove 162 in the soil. The seeds are placed inside the hole (or furrow)162. The pit is defined by a lower portion of soil 166, pit side walls (one of which is shown at 168), and the soil surface 170. The vertical distance between the soil surface 170 and the pit bottom 166 is defined as the planting depth. To obtain a desired planting depth, the pair of depth regulating wheels 116 is forced into contact with, and follows, the soil surface 170. A downforce system (such as the downforce actuator 126 and the parallel links 132, shown in figure 2) is used to apply a downward force on row unit 106 to ensure complete penetration of the opener discs, resulting in ground contact between the depth adjusting wheels 116 and the ground surface 170 with the depth adjusting wheel arms 148 engaging the stop 150.

[0030] Depth adjusting wheels 116 are movably connected to the row unit flank 152 by a set of depth adjusting wheel arms 148. The depth adjusting wheels 116 are each connected to an arm 148 by a joint joint 172. Similarly, each arm 148 is connected to the flank 152 by rotary joint 174, so that they are pivotable about a pivot point 156. When the arms 148 pivot about the pivot point 156, they move up and down in figure 3 to increase or decrease, respectively, the distance between the lowest points of the opening discs 114 and the depth adjusting wheels 116, and thus change the planting depth (the depth of a furrow 162 ).

[0031] In the example shown in figure 3, the mechanical stop 150 is formed by a wedge that is positioned between the depth regulating wheel arm 148 and another mechanical stop 176 that can be defined by a portion of the row unit flank 152 The position of the wedge is, illustratively, changed along a longitudinal axis 178 of the drive mechanism 180. When the position of the wedge 150 is changed along the geometric axis 178, it changes the position of the upper limit of rotation. of the depth gauge wheel arm 148 around the pivot point 156. Thus, when the depth gauge wheel 116 is forced into contact with the ground, the wedge 150 defines the position of the depth gauge wheels 116 relative to the flank of row unit 152 and in relation to the opening discs 114, thus defining the planting depth.

[0032] In one example, the drive mechanism 180 is a lead screw that is mounted within the flank of the row unit 152 using a set of bearings 182 and 184. The lead screw, illustratively, has an outer surface threaded 186 that interacts with a threaded inner surface 188 of a carriage 189 that carries the wedge 150 such that, when the lead screw 180 rotates within the bearings 182 and 184, it drives the movement of the wedge 150 along the longitudinal axis. 178 in a direction that is determined by the direction of rotation of the lead screw 180. Changing the position of the wedge 150 along the geometric axis 178 thus changes the angle between the longitudinal geometric axis 178 of the lead screw 180 and the elongated geometric axis of the arms of depth adjusting wheels 148.

[0033] In one example, the actuator 190 drives the rotation of the lead screw 180 at a controllable speed and in a controllable direction. The actuator 190 may, by way of illustration, be an electric motor with a locking member (such as a self-locking worm drive) mounted between the electric motor and lead screw 180. This may serve to increase the torque available for turn lead screw 180. The self-locking feature of the worm drive allows the worm drive to maintain the set depth while downward force is acting on depth adjuster wheels 116, without torque being applied to the electric motor or other actuator 190. This also, illustratively, allows the position of the wedge 150 to be changed while downward force is acting on the depth regulating wheel 116, and allows the actuator 190 to overcome the frictional forces between the wedge 150 and the depth adjusting wheel arms 148, as well as those forces between the wedge 150 and the mechanical stop 176, and further frictional forces between the inner threaded surface 188 of the carriage 189 and the outer threaded surface 186 of the lead screw 180. A relationship of Different transmission may be used depending on the force available from the actuator 190. In one example, the transmission ratio may be 1:20, although this is just an example.

[0034] Figure 4 shows depth adjusting wheels 116 in two different positions relative to a disc opener 114. The items in Figure 4 are similar to those shown in Figure 3, and they are similarly enumerated. However, when items are in a first planting depth adjustment, the items are designated as “A” and when in a second depth adjustment, they are designated as “B”. In position B, it can be seen that the planting depth is deeper. This is because the wedge 150 is moved along the axis 178 more in the direction towards the bearing 182, so that the depth regulating wheel arm 148B is rotated vertically upwards around the point 156 rather than at position A. Thus, the distance between the lowest point of the disc opener 114 and depth adjusting wheel 116B is relatively large. In position A, the wedge 150 is moved along the axis 178 further towards the bearing 184 so that the depth regulating wheel arm 148A is rotated further downward around the point 156. Thus, the lowest point of the disc opener 114 and this depth adjusting wheel 116A are relatively close to each other. Thus, in position B, pit 168B is relatively deep, while in position A, pit 168A is relatively shallow.

[0035] It should be noted that different configurations of wedge 150 are contemplated here. For example, in one example, the wedge 150 may illustratively be configured as a single piece that engages with both the right and left arms of depth adjusting wheels 148 (both the arm 148 shown in Figure 4 and the other arm depth adjusting wheel, which is not shown in the figures, and which corresponds to another depth adjusting wheel, also not shown in the figures). However, the wedge is, illustratively, configured as a rocker so that it can rotate slightly about the geometric axis 178. This rocker configuration is used to allow some independent movement of the left and right depth adjusting wheels 148 in relation to to the other. This may occur, for example, when the row unit 106 is traveling over uneven terrain.

[0036] In another example, however, the wedge 150 may not have direct contact with the depth adjusting wheel arms 148. Instead, a separate rocker mechanism may be interposed between the wedge 150 and the corresponding set of depth adjusting arms. depth control wheels 148. In yet another example, a separate wedge may interact with each separate depth control wheel arm 148. These and other configurations are contemplated herein.

[0037] It will also be noted that, in one example, the wedge 150 may also include a downward force sensor. A downforce sensor may be a load cell or other sensing device for determining the downforce between the corresponding depth adjuster wheels 148 and the ground (e.g., the downforce margin).

[0038] In another example, the wedge 150 or carriage 189 may incorporate a scraper, a rubber lip, or other mechanisms that may be used to clean the lead screw 180 of debris. Ala may also include a set of plastic bristles or another cleaner.

[0039] In yet another example, the depth adjusting wheel arms 148 can, illustratively, be curved. This can be done so that the position where force is induced on the rocker or wedge 150 and/or the direction and magnitude of the force applied to the rocker or wedge 150 are substantially the same for all depth adjustments. It will be appreciated that, instead of curved arms 148, the surface of the wedge 150 or a corresponding rocker arm may also be curved, or both the wedge 150 and the arms 148 may be curved.

[0040] Figure 5 is a perspective view of an example of the planting depth actuator assembly 154, in more detail. Some of the items are similar to those shown in figure 3 above, and are similarly enumerated. Figure 5 shows that, in one example, a frame structure 200 supports the lead screw 180 and the bearings 182 and 184 in, or affixed to, the flank 152 (not specifically shown in Figure 5). The wedge 150 has the carriage 189 with the threaded inner surface 188 that rides over the threaded outer surface 186 of the lead screw 180. Figure 5 also shows that the lower portion of the wedge 150 is formed as a rocker 202. The rocker 202 may, illustratively, include a first arm engagement portion 204 that engages the depth gauge wheel arm 148 and a second arm engagement portion (not shown) that engages the second depth gauge wheel arm 148 (also not shown). shown). It swings generally in the directions indicated by arrow 206 about a geometric axis 208 of a mechanical assembly that attaches rocker arm 202 to wedge 150 so that it moves with wedge 150 when wedge 150 moves along lead screw 180 The rocking movement about the axis 208 accommodates some independent movement of the depth adjusting wheel arms.

[0041] Figure 5 also shows an example of an actuator 190 that includes the motor 210 that drives the rotation of a self-locking worm drive 212, which rotates within a set of bushings 214 and 216. The motor 210, illustratively drives rotation of the worm screw portion of the worm drive 212. The rotation of the worm screw portion is illustratively translated to the rotational motion of the lead screw 180 through a worm gear (not shown) in a self-locking manner. The worm drive 212 thus acts as a locking member that locks the wedge 150 in place. Therefore, any torque or other forces communicated to the rocker mechanism or wedge 150 are not fed back to the motor drive output 210. Instead, they are transmitted back to the flank 152 through the frame structure 200.

[0042] Figure 6 shows another example of a planting depth actuator assembly 154 that can be used to automatically adjust the planting depth of a row unit 106. Some items are similar to those shown in the previous figures, and they are similarly enumerated. In the example shown in Figure 6, a rocker arm 220 (or other arm contact member or depth gauge wheel thrust member) is supported by an adjustment lever 222 that rotates relative to flank 152 about the geometric axis of rotation. 224. When it rotates about the axis 224, it actuates the member 220 to impart force on, and rotate, the depth regulating wheel arm 148 downward about the pivot point 156, or allows the wheel arm The depth adjuster 148 moves upward about the pivot point 156. The adjusting arm 222, illustratively, has a gear wheel portion 225 that interacts with the threaded surface of the lead screw 180. feed 180 rotates, it thus triggers the movement of the gear wheel portion 226 to correspondingly trigger the rotation of the arm 222 about the geometric axis 224 in the directions indicated by the arrow 228. By choosing the geometry of the adjusting arm 222 and from the gear wheel portion 226, the point at which force is applied from the contact member 220 to the arm 148 can be adjusted. In one example, it may be adjusted so that the point at which member 220 applies force to arm 148 is the same regardless of planting depth. Also, by choosing the geometry of the adjusting arm 222, the force required to turn lead screw 180 in order to drive movement of the member 220 can also be adjusted.

[0043] In the illustrated example, the lead screw 180 may, in contrast, be a self-locking worm drive that is connected to the electric motor 210 by a worm gear. A reduction gear drive can be implemented to provide the desired torque. The position of the adjusting arm 222 can thus, in one example, only be changed by the motor 210 to actively drive the worm drive worm drive 180 because of the self-locking nature of the worm gear. end. When the motor is not actively driving the worm drive portion of the worm drive 180, then any forces that are occurring in the worm drive 180 are transmitted from there to the bearing mounting points 182 and 184, and finally to the flank 152. This allows isolation of any impact forces that may impact the depth control wheel 116, and thus the depth control wheel arm 148, from the electric motor 210 and thus protect the 210 electric motor against peak loads.

[0044] Figure 7 shows another example of a planting depth actuator assembly 154. Some items are similar to those shown in Figure 6, and they are similarly enumerated. In the example shown in Figure 7, the upper limitation of movement of the depth control wheel arm 148 is controlled by rotation of the cam 230. The cam defines a groove 232 for guiding the movement of a support arm 222 and the contact member ( or the rocker arm) 220. When the cam 230 is rotated, a mounting pin 234 follows the groove 232. Because the pin 234 is in, and follows, the groove 232, an upward bearing is provided in situations in which the planter or row unit 106 is raised and the depth adjusting wheel 116 and arm 148 do not compress the contact member 220 against the cam 230. A second groove defined by the member defining the groove 236 guides the movement of the arm 222 and the contact member 220 in a direction generally indicated by arrow 238. Thus, when cam 230 is driven by an actuator (such as an electric motor), pin 234 follows groove 232, but also follows the groove defined by frame structure 236. Therefore, when the cam 230 is actuated, it triggers vertical movement (in the direction indicated by arrow 238) of the contact member 220. Because the contact member 220 rests against the depth adjuster wheel arm(s) 148, it thus causes rotation of the depth regulating wheel arms 148 about their pivot points 156 (as shown in relation to the figures above).

[0045] In the example shown in Figure 7, it can be seen that any vertical force(s) resulting from the gravitational force of the row unit 106 and any additional applied downward force, minus the resistance of the ground to reach the desired depth, are produced solely by the cam 230. Actuation of the cam may be implemented either directly by the teeth partially integrated into the smaller part of the cam or the cam may be connected to a drive shaft on which a gear, such as the gear 242, is assembled. A relatively low speed and relatively high torque are then applied to the cam 230 in order to control the corresponding planting depth. In another example, a transmission box 244 (or gear reduction) between the cam 230 and the gear 242 (which is driven by the motor 210) may be provided. The 244 gearbox can have a relatively high gear ratio in order to provide torque as well as precise depth control. The worm drive can be used for the same reasons as those described above (e.g. a high gear ratio and self-locking characteristics). A planetary gearbox or other types of gearboxes can also be used.

[0046] Figure 8 is a block diagram of an example of a planting machine architecture 250 for automatically controlling planting depth. Architecture 250 includes a planting machine, such as planter 100 (also shown in Figure 1), which has a plurality of row units (such as row units 106 also shown in Figure 1) and may have other items 251 Each row unit may have one or more sensors 252 to 254. The row unit 106 is also shown with other mechanisms 255. The mechanisms 255, illustratively, include depth adjuster wheels 116, disc opener 114, disc wheels 114, closure 118, and some or all of the other mechanisms shown in the previous figures on the row unit 106 or different mechanisms.

[0047] The row unit 106 may also have a wide variety of other components 256.

[0048] Also, as shown in Figure 8, each row unit 106 may have a downforce actuator 126 and a planting depth actuator assembly 154. In some examples, the downforce actuator 126, illustratively, exerts additional downward force on row unit 106 to keep the depth adjuster wheels 116 in contact with the ground, as discussed above with respect to FIG. 2. Also, in one example, the downward force actuator 126 may also be a force actuator upward force that can be used to raise the depth regulating wheels 116 relative to the disc opener 114. In examples in which the downward force actuator 126 is also an upward force actuator that can exert upward force on the depth regulating wheels 116, then the planting depth actuator assembly 154 may not be necessary. These and other examples are described in more detail below.

[0049] The planting depth actuator assembly 154, as illustratively discussed above, controls the distance between the lowest points of the depth adjusting wheels 116 and the disc opener 114. Accordingly, it can be actuated to control the planting depth at which row unit 106 sows seeds. Sensors 252 to 254 may be any of a wide variety of sensors. For example, in one example, sensors 252 to 254 include a downforce sensor that senses the downward force exerted by the downforce actuator 126 on the row unit 106. In another example, they may be a combination of the sensors and logic that senses the downforce margin, as described above. Sensors 252 to 254 may, illustratively, include a position sensor that senses the position of the depth adjusting wheels 116 relative to a disc opener 114. It may be a sensor that senses the depth within the seed pit. Sensors may also include a wide variety of other sensors, such as sensors that monitor soil characteristics (such as moisture, soil compactness, soil type, etc.), and environmental characteristics. Sensors can also sense a wide variety of other variables (machine variables, soil variables, environmental variables, etc.).

[0050] Figure 8 also shows that, in one example, the control system 260 may, illustratively, receive inputs from additional sensors 262 to 264, and may also interact with operator interface mechanisms 266. The interface mechanisms operator input mechanisms 266 may include operator input mechanisms 268, with which the operator 270 may interact in order to control and manipulate the control system 260, and some parts of the planting machine 100.

[0051] Therefore, in the illustrated example, the control system 260 may include one or more processors 272, a database 274, dynamic downforce/upforce control logic 276, the planting depth control system 278 , operator interface logic 280, and may include a wide variety of other items 282. Dynamic downforce/upforce control logic 276 is included in scenarios in which the downforce/upforce actuator 126 may be controlled dynamically by the operator 270, from the operator's compartment of the tractor or other towing vehicle, to controllably communicate either a downward force on row unit 106, an upward force, or both.

[0052] The planting depth control system 278, illustratively, receives sensor inputs and/or operator inputs. It controls the planting depth actuator assembly 154, in each row unit 106, in order to control the planting depth used by the row units 106 in the planting machine 100.

[0053] Operator interface mechanisms 266 may include a wide variety of mechanisms, such as a display screen or other visual output mechanisms, audio mechanisms, tactile mechanisms, levers, the linkage system, buttons, display elements user-actuable (such as icons, displayed connections, buttons, etc.), pedals, control levers, steering wheels, among a wide variety of others. Operator interface logic 280, illustratively, controls the outputs in operator interface mechanisms 266 and can detect operator inputs through operator input mechanisms 268. It can communicate an indication of those inputs to other items in the control system. control 260 or anywhere.

[0054] Sensors 262 to 264 may also be a wide variety of different types of sensors that may be used by the dynamic downforce/upward force control logic 276, the planting depth control system 278, or other items. Some of these are described in greater detail below.

[0055] Figure 8 shows that, in one example, the architecture 250 includes a planting machine (such as the planting machine 100 shown in the previous figures) and a control system 260. The control system 260 can be ported by trailer machine that is towing the planting machine 100, it may be transported by the planting machine 100, or it may be distributed among the trailer machine, the planting machine 100 and a wide variety of other locations. In one example, the control system 260 generates control signals to control the planting machine 100, and as will be more specifically described in greater detail below, the planting depth that the row units in the planting machine 100 are using to plant seeds. 8 also shows that, in one example, the control system 260 can receive sensor signals from a plurality of different sensors 262 and 264. It also shows that the operator 270 (who may be the operator of the tow vehicle) can interact with the control system 260 through operator interface mechanisms 266 which may include, for example, operator input mechanisms 268.

[0056] Figure 9 shows an example of the planting depth control system 278 in more detail. In the example shown in Figure 9, the planting depth control system 278 may include target depth identification logic 290, force/speed estimation logic 292, control signal generator logic 294, planting depth calibration 295, and may include a wide variety of other items 296. The force/speed estimation logic 292 illustratively receives the target depth, which identifies a desired planting depth for the planting machine 100 It may also identify individual planting depths for individual row units 106 on the planting machine 100. It may receive the target depth from the target depth identification logic 290, from an operator, or from another source.

[0057] The target depth identification logic 290 can identify the target depth in a variety of different ways. For example, it may receive a target depth input from operator 318 that identifies a target depth input by operator 270. It may include map data 320 that includes a wide variety of different information correlated to different geographic locations within the field that is being planted. The information may include soil moisture information, soil type information, soil compactness information, and a wide variety of other information, which may be used by target depth identification logic 290 to identify a desired target depth. Logic 290 may also receive sensor data 322 that is indicative of one or more variables that may have an effect on the identified target planting depth. Again, for example, sensor data 322 may be data generated from a soil moisture sensor, a soil type sensor, a soil characteristic or environmental sensor that senses other soil characteristics (such as compaction or other soil characteristics). ) or other environmental characteristics, such as topology, position, etc. Sensor data may include data generated by machine sensors that sense machine variables or other items.

[0058] When the planting machine 100 moves around the field, the target planting depth identified by the target depth identification logic 290 may change based on the location of the planting machine 100. Therefore, the logic 290 may receive a location sensor input indicative of this location, and other inputs that support the desired target planting depth, and may modify the target planting depth when the machine 100 moves around the field. Thus, the target planting depth provided by logic 290 to force/speed estimation logic 292 may vary. All of these scenarios are covered here.

[0059] Force/velocity estimation logic 292 is also shown receiving, by way of example, sensor data 298, one or more operator inputs 300, and may include a wide variety of other inputs 302. By way of illustration, it generates an estimate of the force and speed that will be required to control the planting depth actuator assembly 154 in order to obtain the target planting depth. Thus, it may include the force estimation model 304 which is used to estimate the force that will be required to obtain the target planting depth. It may also, illustratively, include the actuation speed estimation model 306, which generates an estimate of the speed at which the planting depth actuator assembly 154 must be actuated to move from a current planting depth to the planting target. It may also include other items 308. By way of example, the force estimation model 304 may estimate the force that needs to be applied to the depth gauge wheel arms 148 in order to move the depth gauge wheel in the desired direction (or up or down in relation to the disc opener 114). The actuation speed estimation model 306, illustratively, generates an indicative estimate of how quickly the actuator assembly 154 must be actuated to move the depth regulating wheels to the desired target depth. For example, it may be undesirable to change the depth profile of the seed hole too quickly. Instead, it may be desired to alter the planting depth gradually to obtain a desired pit contour or pit depth profile. Thus, the actuation speed estimation model 306 can generate an estimate that indicates how quickly the actuator assembly 154 must be actuated to change the planting depth.

[0060] In one example, force estimation and speed estimation are provided to control signal generation logic 294 which, illustratively, includes the downward force/upward force control signal generator 310, the of planting depth actuator control signal 312, and may include other items 314. In some examples, the control signal generator 310 will control the downforce/upforce actuator 126 (shown in FIG. 8) to remove any applied downward force or to provide a downward force so that the planting depth actuator assembly 154 does not need to overcome any applied downward force in changing the planting depth. The control signal generator 312 then, illustratively, controls the planting depth actuator assembly 154 to change the planting depth at a rate corresponding to the speed estimated by the model 306. The output of the control signal generator logic 294 is, illustratively, a set of control signals 316 that are output to the row units 106 in order to control the downforce/upforce actuator 126 and/or the planting depth actuator assembly 154.

[0061] As mentioned above, a parameter associated with planting is the depth below the soil surface at which the seed is planted. Various methods have been shown to sense the depth at which seed is being placed during planting. Planting depth (along with other variables such as soil texture, temperature, humidity, etc.) can affect plant emergence time and vigor. Generally, production is optimized by all plants emerging as uniformly as possible, but there may be conditions in which it is better to stagger plant emergence or maturity. In addition, emergence may differ from one piece of soil to another if the planting depth is kept constant. Therefore, variable planting depth can be used to obtain uniform emergence as well.

[0062] While the row unit is engaging the soil and planting, the forces required to change the planting depth in motion can be significant. Actuators that are large enough and strong enough to operate against such forces can be relatively large and expensive. One way to change the planting depth, as described below, may involve stopping the planting machine, raising the row units out of the ground, and then automatically actuating the actuator assembly 154 to change the planting depth accordingly. automatically, before continuing. This may occur in the end rows or may occur during a brief pause in forward motion to raise the machine during planting to facilitate such an adjustment. The actuators needed to change planting depth can therefore be relatively small, because they do not need to overcome the large downward forces involved with some types of planting equipment.

[0063] In another example that is described in more detail below, the downforce/upward force control signal generator 310 controls the downforce/upward force actuator 126 in conjunction with the depth actuator control signal generator planting depth 312 that controls the planting depth actuator assembly 154 to change the planting depth. The control signal generator 310 can control the downforce actuator 126 to momentarily relieve any downward force applied, and to optionally provide the required force or to raise (upward force) or further lower (downward force). one or more row units 106 into the ground with respect to where the depth regulating wheels 116 are running on the ground surface. The control signal generator 312 can then control the planting depth actuator assembly 154 to simply lock at the new desired depth. This reduces the need for the assembly 154 to be able to exert the additional force (and thus incur additional cost and additional structural effort) that is required to overcome the downward force, whilst still allowing the row unit 106 to adjust the planting depth accordingly. movement. Thus, it can be seen that, in one example, the downforce/upforce control signal generator 310 can be used to provide all of the power necessary to change the planting depth, in which case the downforce control signal generator 310 planting depth actuator 312 controls planting depth actuator assembly 154 to simply lock at the new depth. In another example, the downforce/upforce control signal generator 310 may generate a portion of the necessary force to adjust the relationship between depth adjuster wheels 116 and opener 114, or it may simply be used to remove any applied downforce. dynamically so that planting depth can be adjusted using a smaller actuator. In these latter scenarios, the planting depth actuator assembly 154 includes an actuator in addition to the actuator 126, which provides additional planting depth adjustment force to change the relationship between depth adjusting wheels 116 and the disc opener 114, and to make the planting depth adjustment, and then to lock this adjustment in place.

[0064] Also, it will be noted that, in one example, the planting depth control system 278 controls the planting depth using a control curve that plots the desired planting depth against a position of the mechanical stop 150 in the control actuator assembly. planting depth 154. Control curve calibration can be used to accommodate changes in the relationship between planting depth and a mechanical stop position. For example, when opener 114 and depth adjuster wheels 116 are used, they may wear at different rates. Manufacturing and assembly tolerances may also lead to changes. Therefore, as discussed in greater detail below with respect to Figures 11 to 13, the calibration system 295 can calibrate the control curve.

[0065] Before describing the operation of the planting depth control system 278 in more detail, a number of observations will first be noted. When the planting depth of a row unit is changed, it can be changed either from a shallower depth to a deeper depth, or from a deeper depth to a shallower depth. When the planting depth is changed within a field, when the planting machine 100 is moving and planting (e.g., when it is changed in motion), it may be desired that transitions between two planting depth settings and corresponding pit contours are uniform. That is, to be uniform, the pit contour when moving from a shallower planting depth to a deeper planting depth must be the same as the pit contour when moving from a deeper planting depth to a deeper planting depth. shallower plantation.

[0066] This can be very difficult to achieve because the forces required by the actuator assembly 154 to go from a deep planting depth to a shallower planting depth are often much greater than to go in the opposite direction (from a shallower planting depth). planting for a deeper planting depth). This is because the downward force on the row unit 106 is acting against the transition from a deep planting depth to a shallow planting depth. Therefore, in order to reduce the planting depth, the entire row unit 106 must be lifted against its weight and against any downward force provided by an active (pneumatic or hydraulic) or passive (mechanical spring) downward force system 126. Even if the downforce actuator 126 is dynamic (in that it can be controlled from the operator's compartment or by a moving control system), and even when the additional downforce added by the downforce actuator 126 can be relieved, there typically still remains significant force acting against the transition from deep to shallow planting depths due to the weight of the row unit 106 itself. When the downward force actuator 126 is not dynamic, then the difference in forces acting against the deep to shallow transition versus the forces acting against the shallow to deep transition is even significantly greater.

[0067] Because the forces acting against the change in planting depth are very different depending on the direction of adjustment (e.g., deep to shallow or shallow to deep), it can be very difficult to obtain a uniform pit contour in the shallowing movement. to deep and deep to shallow. For example, it may take longer to overcome the force on the row unit 106 when moving it in one direction than to overcome the force when moving it in the other direction. This can make the pit contour (the change from current planting depth to target planting depth) much steeper in one direction than the other. Furthermore, attempting to actuate a depth adjustment mechanism (such as assembly 154) without first obtaining an estimate of the required actuation force may lead to undesired behavior, which is known as backlash. In a backlash scenario, in which the actuating force is not known prior to attempting to make a depth regulation adjustment, the planting depth may actually move in the wrong direction before it begins to move in the correct direction. By way of example, when moving from a deep planting depth to a shallower planting depth, the total force on the row unit (as described above) must be overcome. The depth adjustment actuator may not normally be active at all times. Therefore, if a locking mechanism, which is used to maintain the row unit at a desired planting depth, is unlocked so that an adjustment can be made, then at the beginning of the planting depth change, the row unit 106 can begin movement to even a deeper planting depth before beginning to move to a shallower planting depth, which results in a very undesirable pit contour. However, the system currently estimates the actuation force and actuation speed, which are necessary so that force can be immediately applied when (or just before when) the depth adjustment mechanism is unlocked. This avoids unwanted pit contouring where the planting depth may currently move in the wrong direction before eventually moving to the target planting depth.

[0068] According to an example, the planting depth control system 278, illustratively, controls the planting depth actuator assembly 154 so that it has the same adjustment characteristics, regardless of the adjustment direction. It can also include information about planting speed to allow adjustment characteristics to be consistent across a georeferenced coordinate system, so that the same pit contour can be obtained at different planting speeds.

[0069] Figures 10A and 10B (collectively referred to herein as Figure 10) illustrate a flowchart showing an example of the operation of the planting depth control system 278 and a row unit 106 of the planting machine 100, upon changing the depth plantation, in more detail. It is first assumed that the planter 100 is operating in a field. This is indicated by block 330 in the flowchart of Figure 10. The force/speed estimation logic 292 then receives a target planting depth. This is indicated by block 332. Again, as discussed above, this may be based on an operator input 318. This is indicated by block 334. It may also be from an automatic system, such as target depth identification logic 290. This is indicated by block 336. It can also be received in a wide variety of other ways, and this is indicated by block 338.

[0070] The adjustment identification logic 303 then, illustratively, receives the target depth, and a current planting depth. This is indicated by block 340 in the flowchart of Figure 10. The current planting depth may be an estimated planting depth that is estimated based on sensor signals that sense a position of depth adjusting wheels 116 and openers 114. It may also be a directly sensed planting depth that uses a planting depth sensor to sense the depth of the seed hole or furrow.

[0071] The adjustment identification logic 303 then identifies whether an adjustment should be performed based on the received target planting depth and the current planting depth. If an adjustment must be made, it illustratively identifies a magnitude of the adjustment and a direction for the adjustment (such as what the magnitude of the adjustment value is and whether it should be made to move the planting depth from the shallowest to deeper or deeper to shallower). It provides these items for the force estimation model 304 and the actuation speed estimation model 306. The determination of whether an adjustment should be made, and the magnitude and direction of the adjustment, is indicated by blocks 342 and 344 in the figure. 10.

[0072] It will be noted that models 304 and 306 can be integrated into a single model that receives inputs and generates outputs indicative of the estimated force and actuation speed. They can be two separate models that process inputs in parallel or sequential models in which the output of one model feeds into the input of another model. All of these and other architectures are covered here.

[0073] It will also be noted that the force/velocity estimation logic 292 (and models 304-306) can detect or receive a wide variety of inputs that can be used to generate the outputs. This is indicated by block 348. For example, the inputs may include an input indicating the current planting depth and adjusting the current planting depth. This is indicated by block 350. They may include the magnitude of the planting depth adjustment and the direction of the planting depth adjustment, as indicated by block 352. They may include a wide variety of environmental or crop sensor signal data. or map data 354. This may include such factors as features sensed by crop feature sensors, environmental features sensed by environmental feature sensors, topology information fed into a topology map, among a wide variety of other features. Inputs may also include the downward force 356 acting on the row unit 106 as well as the downward force margin 308. Examples of these are described above.

[0074] Logic 292 may receive a travel quality value 360, indicative of a travel quality of the row unit 106. This value may be generated by accelerometers that generate a signal indicative of accelerations measured at the row unit 106, or in other ways. It may receive a planting speed input 362 indicative of the ground speed of the planting machine 100. It may include an input that identifies the kinematics of the system (such as measurements, angles, and other values that define the kinematics of the mechanisms used when adjusting planting depth). The kinematics of the system are indicated by block 364 in the flowchart of Figure 10. And may include a wide variety of other inputs, such as the position of the depth control wheel, or other items 366.

[0075] The force estimator model 304 and the actuation speed estimation model 306 then generate an estimate of the force and actuation speed to change the planting depth to the target depth. This is indicated by block 368. This may be based on a desired pit contour 370. The desired pit contour 370 may define how quickly the depth should be changed or the magnitude of the change per linear foot of the pit, or other factors. Thus, given the planting speed and given the magnitude of adjustment, the force and speed estimate can be provided to change the planting depth based on the desired pit contour.

[0076] Again, estimates can be generated using one or more models. This is indicated by block 372.

[0077] Depth adjustment can also be made through a series of incremental changes. This is indicated by block 374. By way of example, it may be desirable to make a planting depth adjustment in incremental steps. Therefore, the output of the force/speed estimation logic 292 may be an output indicating how to control the planting depth actuator assembly 154 to move from the current planting depth to the target planting depth in a series of incremental steps. This can be done in lieu of controlling the actuator assembly 154 to move continuously from the current depth to the target depth. Estimating the force and speed of actuation to change the current planting depth to the target planting depth can be done in a wide variety of other ways as well, and this is indicated by block 376.

[0078] As discussed above, in one example, force and velocity estimates can be made on a system that does not have any additional downward force applied or that does not have a dynamically changing downward force (such as in a system that does not have a hydraulic or pneumatic downforce actuator, but is instead in a system that has a relatively static downforce system, such as one that communicates downforce through a set of mechanical springs or in other ways).

[0079] If, as indicated by block 378, planting depth adjustment is not to be made against an actively applied downward force, then planting depth actuator control signal generator 312 illustratively controls the planting depth actuator assembly 154 to apply the estimated force (received from model 304) to the actuation speed (received from model 306) to change the planting depth. This is indicated by block 380. Again, this may be provided as a continuous signal to continuously actuate actuator assembly 154 (e.g., to rotate lead screw 180 or other actuator) to move the depth gauge wheel arms. 148 to change the planting depth in a continuous control step. This can also be done by making incremental changes that incrementally move the depth control wheel arms 148 to change the planting depth incrementally, from the current planting depth to the target planting depth. This can also be done in other ways.

[0080] If, in block 378, it is determined that the planting depth change must be made against an actively applied downward force, then, in block 382, the downward force control signal generator 310 determines whether the downward force descending is applied by a dynamically changeable system, or whether it is a relatively static system (e.g. based on a mechanical spring). If there is an active downward force applied to the row unit, but it is not dynamically changeable, then processing continues again at block 380 where planting depth actuator control signal generator 312 generates control signals to control the planting depth actuator assembly 154 for changing the planting depth as discussed above.

[0081] However, if, in block 382, it is determined that the actively applied downward force is dynamic in nature, and that it can be controlled quickly, then the downward force control signal generator 310 generates control signals to control the downforce actuator 126 to remove the actively applied downforce. This is indicated by block 384. In the example described here, this is done by controlling the downforce actuator 126 to become passive or by controlling the actuator to actively remove the downforce in other ways as well. This is indicated by blocks 386 and 388. Also, in one example, the row unit may be temporarily lifted out of the ground so that the actively applied downward force is no longer working against the depth setting change (e.g. For example, the change may be made during a headland turn or during a brief pause while the row unit 106 is raised off the ground). These are just examples.

[0082] The planting depth actuator control signal generator 312 then generates control signals 316 to control the planting depth actuator assembly 154 to change the planting depth. This is indicated by block 390 in the flowchart of Figure 10. It will be noted that, as described above, the planting depth actuator assembly 154 may be incorporated into the downforce actuator 126, such that the downforce actuator 126 also includes a upward force actuator that can exert upward force on the row unit, rather than just downward force. In this case, the upward force actuator can also be controlled when changing the planting depth. This is indicated by block 392. The planting depth can be changed by controlling a separate planting depth actuator assembly 154, as discussed above. This is indicated by block 394. The actuator (e.g., the motor) in the planting depth actuator assembly 154 can be controlled at the estimated actuation speed so that the planting depth adjustment is made over a certain period of time. This is indicated by block 396. Planting depth actuator assembly 154 can be controlled based on a desired pit contour. For example, it can be controlled to make the adjustment, while considering the speed of the planting machine 100, so that the change from the current depth to the target depth is made in accordance with a desired pit contour (so that the pit do not change depth too quickly over a given linear distance) or otherwise. Control of the planting depth actuator assembly based on a desired pit contour is indicated by block 398.

[0083] Once the new planting depth is obtained, then the planting depth actuator control signal generator 312 generates control signals to control the planting depth actuator assembly 154 to lock the new planting depth at the place. This is indicated by block 400. By way of example, the planting depth actuator assembly 154 may include the worm drive. In this case, once the target planting depth is obtained, the worm drive is self-locking. In another example, the new planting depth may be locked in other ways so that forces or accelerations applied to the row unit 106 via the depth adjusting wheels 116 do not transmit back to the actuator (e.g., the electric motor or another motor) in the planting depth actuator assembly 154. Instead, those forces or accelerations are, illustratively, transmitted to the frame of the planting machine, such as the flank 152, or other structural mechanisms.

[0084] Planting depth adjustment can also be done in a wide variety of other ways. This is indicated by block 402 in the flowchart of figure 10.

[0085] Once the planting depth adjustment has been made and locked, then the downforce control signal generator 310, illustratively, controls the downforce actuator 126 to reapply the active downforce that was removed in the block 384. The reapplication of downward force after the planting depth adjustment has been made is indicated by block 404 in the flowchart of figure 10.

[0086] It will be appreciated that, in one example, the planting depth control system 278 may continue to monitor various sensor signals and other inputs and make planting depth changes, on the fly, until the planting operation is completed. This is indicated by block 406 in the flowchart of figure 10.

[0087] Figure 11 is a block diagram of an example of the planting depth calibration system 295. In the example shown in Figure 11, the system 295 is seen receiving a calibration start trigger 410, motor torque signal 412, and can receive a wide variety of other items 414. Based on the items received, it provides an adjusted control curve 416 that the planting depth control system 278 can use to control the planting depth. As discussed above, the control signal generator logic 294 can access a control curve that plots the desired planting depth versus an indication of the position of the mechanical stop 150. However, a position of the mechanical stop 150 is determined based on the kinematics of the physical system (such as measurements, angles, physical relationships, etc., on portions of the row unit and planting depth actuator assembly 154 that are used to adjust planting depth). The various kinematic values can be obtained at the time of manufacture, or they can be fed in later. Some of those values can also be sensed.

[0088] There are some conditions under which kinematic values may change. For example, when a row unit 106 is used, openers 114 and depth adjuster wheels 116 may exhibit wear. This can cause their diameters to change, and they may not change uniformly with respect to each other. Therefore, a position of mechanical stop 150, when it rests against depth adjusting wheel arms 148, may result in a different planting depth than before the depth adjusting wheels 116 and openers 114 wear out. Also, the kinematic values used to generate the control curve may change based on manufacturing and assembly tolerances. Therefore, from one row unit to the next, the kinematic values may be slightly different, even when the parts are new. These and other factors may affect kinematic values and may thus affect the relationship between a position of mechanical stop 150 along lead screw 180, and the resulting planting depth. Thus, the planting depth calibration system 295 can intermittently perform a calibration process that adjusts the control curve based on new kinematic values identified during the calibration process. The adjusted control curve 416 can then be used by the planting depth control system 278 to control the planting depth.

[0089] In the example shown in Figure 11, the planting depth calibration system 295 illustratively includes calibration trigger detection logic 418, arm contact member position logic 420, engine torque sensing logic 422, engine revolution tracking logic 424, arm contact member position detection logic 426, calibration curve zero point identifier logic 428, curve adjustment logic control system 430, wear calculation logic 431, and may include a wide variety of other items 432. Before describing the operation of system 295 in more detail, a brief description of some of the items in system 295, and their operation, will be provided first.

[0090] Calibration trigger detection logic 418 detects a calibration start trigger 410 that indicates that a calibration operation must be performed. This may include operator input, or it may include an automatic trigger, such as where the system monitors a number of acres that have been planted since the last calibration process was performed. These and other triggers are discussed below.

[0091] The contact member positioning logic 420, illustratively, generates an output to the control signal generator logic 294 (shown in Figure 9) to generate control signals to move the mechanical stop (or contact member). arm contact) 150 to a desired position along the lead screw 180. The motor torque sensing logic 422, illustratively, receives a motor torque signal 412 indicative of the torque of the motor driving the lead screw 180 , in the planting depth actuator assembly 154. The motor revolution tracking logic 424 may include a revolution sensor, or other sensor that senses a number of revolutions made by the motor output driving the lead screw 180. arm contact member position detection 426, illustratively, detects a position of the mechanical stop (or arm contact member) 150. This is described in greater detail below. The calibration curve zero point identifier logic 428 illustratively identifies a new calibration point, and the control curve adjustment logic 430 recalibrates (or adjusts) the control curve based on the calibration points. which are identified during the calibration operation. Wear calculation logic 431 can calculate wear on opener 114 and/or depth adjuster wheels 116. This is also discussed in greater detail below.

[0092] As mentioned, the control curve adjustment logic 430 adjusts the control curve based on the calibration points identified by the calibration point identifier logic 428. In one example, the calibration process can be performed for a plurality of different calibration points, and the control curve can be adjusted based on those points. In another example, the calibration process can be performed to identify a single calibration point, and the control curve can be adjusted based on this calibration point.

[0093] Figures 12A-12C (hereinafter referred to as figure 12) show a flowchart illustrating an example of the operation of the planting depth calibration system 295 in carrying out a calibration process. Figures 13A-13D are schematic/symbolic illustrations of a portion of the row unit 106, to illustrate different parts of the calibration process. Some items in Figures 13A-13D are similar to those shown in Figure 4, and they are enumerated in a similar manner. Figures 12A-13D will now be described in conjunction with each other.

[0094] In one example, calibration trigger detection logic 418 first detects a calibration start trigger. This is indicated by block 434 in the flowchart of Figure 12. The calibration start trigger 410 can take a variety of different forms. For example, it may be an operator input 436, or it may be an indication that a usage limit has been reached, as indicated by block 438. For example, calibration start trigger 410 may be generated when the control system 260 determine that a row unit was used to seed a limit number of acres, or that it was used for a limit amount of time. In another example, the use threshold 438 may be determined based on soil type, such that if the soil is more likely to promote weathering, then the trigger is generated sooner than if the soil is less likely to promote weathering. The calibration start trigger can be generated based on a wide variety of other criteria that can also indicate wear, and this is indicated by block 440.

[0095] Once the calibration start trigger has been detected, then the contact member positioning logic 420 positions the arm contact member (or mechanical stop) 150 to the maximum planting depth. This is indicated by block 442. An example of this is illustrated in the symbolic representation shown in Figure 13A. It can be seen that the arm contact member 150 has been moved to its position closest to the bearing 182 (or to another known position along its travel range). It is also out of contact with the depth control wheel arm 138. This is indicated by block 444 in the flowchart of Figure 12. The arm contact member 150 can be positioned for maximum planting depth in other ways as well, and this is indicated by block 446.

[0096] Next, the row unit 106 is lowered (and the entire planter can be lowered) onto the relatively flat base. This is indicated by block 448. In one example, the ground may be a firm surface, such as concrete, so that neither the depth adjusting wheel 116 nor the opener 114 penetrates the ground. This is indicated by block 450. It is also controlled so that both the depth adjusting wheels 116 and the opener 114 are in contact with the ground, as indicated by block 452. This ensures that the lower portions of the openers 114 and the wheels depth regulators 116 are generally coplanar, in a horizontal plane, generally defined by the ground surface 454. This is also indicated by block 456 and can be detected automatically or through observation, as indicated by block 457 in the flowchart of figure 12 .

[0097] Figure 13A also shows that, in one example, the depth control wheel arms 148 include a sensor target 458, together with a distance sensor 460 (which may be an inductive sensor, or other sensor) that measures the distance to the target 458. The target 458 is thinned so that, when the depth control wheel arm 148 pivots about the pivot point 156, the distance between sensor 460 and target 458 changes approximately linearly (or in another relationship known) by changing the angle of the depth adjustment wheel.

[0098] Returning again to the flowchart of Figure 12, once the row unit 106 is lowered onto the relatively flat floor, then the arm contact member position detection logic 426 measures the position of the depth adjuster wheel using position sensor 460 and target 458, or another sensor. This is indicated by block 462 in the flowchart of figure 12. In one example, the measurement is made for both depth control wheels on a pair of depth control wheels, as indicated by block 464. The measurement can also be made from other ways, and this is indicated by block 466.

[0099] The contact member positioning logic 420 then generates a control signal and provides the same to the control signal generator logic 294 to actuate the motor to move the mechanical stop (or arm contact member) 150 in one direction to decrease planting depth. Referring again to Figure 13A, this will cause the mechanical stop 150 to move more in the direction toward the bearing 184. Motor actuation to move the mechanical stop 150 in this direction is indicated by block 468 in the flow chart of Figure 12. While this is happening, engine revolution tracking logic 424 tracks the number of engine revolutions when it is moving mechanical stop 150. Engine revolution tracking is indicated by block 470.

[00100] This continues until the engine torque sensing logic 422 senses that the mechanical stop 150 has contacted the depth regulating wheel arm 148, as illustrated in the symbolic diagram shown in figure 13B. In one example, when this occurs, the torque output by the motor by turning the lead screw 180 will increase, and this will be indicated by the motor torque signal 412. When this occurs, the contact member positioning logic 420 provides a signal to the control signal generator logic 294 so that it stops the engine rotation. The determination that the mechanical stop 150 is in contact with a depth regulating wheel arm 148, such as through an increase in engine torque or otherwise, is indicated by blocks 472, 474 and 476 in Figure 12. The stoppage of the engine, once when the mechanical stop 150 comes into contact with the depth adjusting wheel arm 148, is indicated by the block 478.

[00101] The arm contact member position detection logic 426 then determines a position, along its travel length, of the arm contact member (or mechanical stop) 150. This is indicated by block 480 in the flow chart from figure 12. This can be done in a variety of different ways. For example, using the number of engine revolutions, as indicated by block 482, that were required to move the mechanical stop 150 from a position shown in Figure 13A to a position shown in Figure 13B, together with the gear ratio of any gearbox. that is installed between the motor drive shaft and the lead screw 180 (as indicated by block 484), together with the screw pitch on the lead screw 180 (as indicated by block 486), logic 426 can identify how far the mechanical stop 150 has moved through its travel range along the lead screw 180. A position along its travel range can be identified in other ways as well, and this is indicated by block 488.

[00102] Once this position is known, the calibration point identifier logic 428 illustratively identifies this as a zero point on the calibration curve, where the depth adjuster wheel 116 and the opener 114 are in the exact same height so that the corresponding planting depth would be zero. The control curve adjustment logic 430 then adjusts the control curve based on the identified calibration zero point. This is indicated by block 490 in the flowchart of figure 12. The identification of this calibration point as a zero calibration point on the control curve is indicated by block 492. It, illustratively, shifts the control curve based on the new point zero, and this is indicated by block 494. It can adjust the control curve to accommodate wear or other changes in the system kinematics, in other ways as well, and this is indicated by block 496.

[00103] The wear calculation logic 431 then, illustratively, calculates the wear on the opener and depth adjusting wheels. This is indicated by block 498. In one example, where a depth gauge wheel position sensor 460 is used, and where arm contact member position detection logic 426 is also used (which calculates a stop position mechanic 150 based on engine revolutions and gear ratio and screw pitch), then wear calculation logic 431 can calculate wear on both the depth adjuster wheel 116 and the opener 114. However, where only one of those sensors of position is used, then the combined wear of both the opener 114 and the depth adjusting wheel 116 can be calculated. The combined wear calculation is indicated by block 500 and the separate calculation of depth adjuster wheel wear and opener wear is indicated by block 502.

[00104] The wear calculation logic 431 then provides an indication of wear on the depth adjusting wheels 116, and the opener 114, and this is indicated by block 504. It may be provided to a storage component, as indicated by the block 506, where it can be accessed at any time. It may also be displayed to the operator, as indicated by block 508. In one example, wear calculation logic 431 compares the calculated wear to a wear limit to determine whether to replace depth adjuster wheels 116 or opener 114 is necessary. This is indicated by block 510. If necessary, this may be brought to the operator's attention (or someone else's attention) via an alert message, or other type of output mechanism. Providing wear can also be done in other ways, and this is indicated by block 512.

[00105] As discussed above, the planting depth calibration system 295 can perform either single-point calibration (where a single calibration point is identified, as discussed above with respect to Figure 12) or can perform a multi-point calibration, in which case which multiple calibration points can be identified and used to fit the calibration curve. If multipoint calibration is to be performed, as indicated by block 514, then, in one example, a calibration element (illustrated by element 516 in Figures 13C and 13D) is placed between the ground and the depth adjusting wheels 114, while allows the opener 114 to remain in contact with the ground. In one example, the calibration element 516 has a known height. This is indicated by block 518 in the flowchart of figure 12. Maintaining the opener 114 in contact with the ground is indicated by block 520. The calibration element 516 can be placed under the depth adjusting wheels in a single row unit 106, or under all depth adjusting wheels of all row units 106 in the planter. The calibration element can be placed between the ground and the depth adjusting wheels in other ways as well, and this is indicated by block 522.

[00106] The planting depth calibration system 295 then performs motor actuations to move the arm contact member 150 from a travel end to be in contact with the depth adjuster wheel arms 148 in order to to identify another calibration point on the control curve. This is indicated by block 524 in the flowchart of Figure 12, and is described in greater detail above with respect to Figures 13A and 13B. It is also shown in more detail in figures 13C and figure 13D. For example, Figure 13C shows that the arm contact member 150 is at its furthest extent of travel in the direction toward the bearing 182. Figure 13D shows that the arm contact member 150 has now been moved until it engages with depth control wheel arm 148. Again, this can be sensed based on an increase in torque at the engine output by driving the lead screw 180, or in other ways.

[00107] Once the distance traveled by member 150 has been identified (based on engine rotations, any gear ratio, lead screw pitch 180, etc.), then this, in combination with the known deviation between opener 114 and depth gauge wheels 116 (based on the known height of the calibration element 516), can be used to identify another calibration point. The calibration point identifier logic 428 identifies the calibration point, and the control curve adjustment logic 430 adjusts the control curve again based on the newly identified calibration point. Adjustment of the control curve based on the additional calibration point is indicated by block 526 in the flowchart in Figure 12.

[00108] If additional calibration elements 516, which have different, known heights are provided, then the same process can be repeated to identify even more calibration points which can be used to adjust the calibration curve. If more calibration points must be identified, as indicated by block 528 in the flowchart of Figure 12, processing reverts to block 518.

[00109] Otherwise, however, then the planting depth control system 578, illustratively, controls the planting depth actuator assembly 154 using the adjusted control curve 416. This is indicated by block 530 in the flowchart of the figure 12.

[00110] The present discussion mentioned processors and servers. In one embodiment, the processors and servers include computer processors with associated memory and timing circuitry, not separately shown. They are functional parts of the systems or devices to which they belong and by which they are activated, and they facilitate the functionality of other components or items in those systems.

[00111] Also, a number of user interface views have been discussed. They can take a wide variety of different forms and can have a wide variety of different user-actuable input mechanisms arranged within them. For example, user-actuable input mechanisms can be text boxes, check boxes, icons, connections, drop-down menus, search boxes, etc. They can also be acted upon in a wide variety of different ways. For example, they can be actuated using a point-and-click device (such as a rolling ball or mouse). They can be actuated using hardware buttons, switches, a control lever or keyboard, free levers or touch panels, etc. They can also be actuated using a virtual keyboard or other virtual actuators. In addition, when the screen on which they are displayed is a touch screen, they can be actuated using touch gestures. Also, when the device displaying them has voice recognition components, they can be actuated using voice commands.

[00112] A number of databases were also discussed. It will be noted that they can be broken down into multiple databases. All may be local to the systems that access them, all may be remote, or some may be local while others are remote. All of these configurations are covered here.

[00113] Also, the figures show a number of blocks with functionality prescribed for each block. It will be noted that fewer blocks can be used, so that the functionality is performed by fewer components. Also, more blocks can be used with functionality distributed among more components.

[00114] It will also be noted that the elements of figures 8 and 9, or portions thereof, can be arranged in a wide variety of different devices. Some of those devices include servers, desktop computers, portable computers, tablet computers, or other mobile devices such as pocket computers, cell phones, smart phones, multimedia players, personal digital assistants, etc.

[00115] Figure 14 is an example of a computing environment in which the elements of Figures 8 and 9, or parts thereof, (for example) can be developed. Referring to Figure 14, an example system for implementing some embodiments includes a general purpose computing device in the form of a computer 810. Computer components 810 may include, but are not limited to, a processing unit 820 (which may comprise processors or servers shown in the preceding figures), a system memory 830, and a system bus 821 that couples various system components, including system memory, to the processing unit 820. The system bus 821 may be any of various types of bus structures including a memory bus or memory controller, a peripheral bus, and a local bus using any of a variety of bus architectures. The memory and programs described with respect to figures 8 and 9 can be developed in the corresponding portions of figure 14.

[00116] Computer 810 typically includes a variety of computer-readable media. The computer-readable media can be any available media that can be accessed by the computer 810 and includes both volatile and non-volatile media, removable media and non-removable media. By way of example, and not limitation, computer readable media may comprise computer storage media and communication media. Computer storage medium is different from, and does not include, a modulated data signal or carrier wave. It includes hardware storage media including removable and non-removable media, both volatile and non-volatile, implemented in any method or technology for storing information, such as computer-readable instructions, data structures, program modules or other data. Computer storage media includes, but is not limited to, RAM, ROM, EEPROM, flash memory or other memory technology, CD-ROM, digital versatile discs (DVD) or other optical disc storage, magnetic cassettes, magnetic tape , storage by magnetic disk or other magnetic storage devices, or any other medium that can be used to store the desired information and that can be accessed by computer 810. The media can incorporate computer readable instructions, data structures, modules of program or other data in a transport mechanism and includes any means of providing information. The term “modulated data signal” means a signal that has one or more of its characteristics adjusted or altered in such a way as to encode information in the signal.

[00117] System memory 830 includes computer storage media in the form of volatile and/or non-volatile memory, such as read-only memory (ROM) 831 and random access memory (RAM) 832. An input system/ Basic output 833 (BIOS), containing the basic routines that help transfer information between elements within computer 810, such as during startup, is typically stored in ROM 831. RAM 832 typically contains data and/or program modules that 14 illustrates operating system 834, application programs 835, other program modules 836, and program data 837.

[00118] Computer 810 may also include other removable/non-removable, volatile/non-volatile computer storage media. By way of example only, Figure 14 illustrates a hard disk drive 841 that reads from, or writes to, non-removable, non-volatile magnetic media, an optical disk drive 855, and non-volatile optical disk 856. The disk drive hard drive 841 is typically connected to the system bus 821 through a non-removable memory interface, such as interface 840, and the optical disk drive 855 is typically connected to the system bus 821 through a removable memory interface, such as the 850 interface.

[00119] Alternatively, or in addition, the functionality described here may be performed, at least in part, by one or more logical hardware components. For example, and without limitation, illustrative types of hardware logic components that may be used include programmable logic gate networks (FPGAs), application-specific integrated circuits (e.g., ASICs), application-specific standard products (e.g., , ASSPs), systems on a chip (SOCs), complex programmable logic devices (CPLDs), etc.

[00120] The controllers and their associated computer storage means discussed above and illustrated in Figure 14, provide storage of computer-readable instructions, data structures, program modules and other data for the computer 810. In Figure 14, for For example, hard disk drive 841 is illustrated as storing operating system 844, application programs 845, other program modules 846, and program data 847. Note that these components may be either the same or different from operating system 834. application programs 835, other program modules 836, and program data 837.

[00121] A user can feed commands and information to computer 810 through input devices, such as a keyboard 862, a microphone 863, and a pointing device 861, such as a mouse, rolling ball, or touch panel. Other input devices (not shown) may include a control stick, game panel, satellite dish, explorer or similar. These and other input devices are often connected to the processing unit 820 through a user input interface 860, which is coupled to the system bus, but may be connected through other interfaces and bus structures. A visual display 891 or other type of display device is also connected to the system bus 821 through an interface, such as a video interface 890. In addition to the monitor, computers may also include other peripheral output devices, such as such as speakers 897 and printer 896, which can be connected via a peripheral output interface 895.

[00122] Computer 810 is operated in a networked environment using logical connections (such as a local area network - LAN, WAN wide area network, a CAN controller area network) to one or more remote computers, such as a remote computer 880.

[00123] When used in a LAN-connected environment, the computer 810 is connected to the LAN 871 through a network interface or adapter 870. When used in a WAN-connected environment, the computer 810 typically includes a modem 872 or other means of establishing communications over the WAN 873, such as the Internet. In a networked environment, program modules can be stored on a remote memory storage device. 14 illustrates, for example, that remote application programs 885 may reside on the remote computer 880.

[00124] It should also be noted that the different modalities described here can be combined in different ways. That is, parts of one or more modalities may be combined with parts of one or more other modalities. All of this is covered here.

[00125] Example 1 is a row unit in a planting machine, comprising: a support frame; a pit opener; a depth adjusting wheel; a depth adjusting wheel arm that couples the depth adjusting wheel to the support frame; and a planting depth actuator assembly, selectively engaging the depth control wheel arm, which receives a planting depth signal generated based on a target planting depth, and applies a force to the depth control wheel arm to position the depth adjusting wheel in relation to the hole opener to obtain the target planting depth.

[00126] Example 2 is a row unit according to any or all of the previous examples, wherein the planting depth actuator assembly comprises: an arm contact member; a system of connections; and a motor, coupled to the arm contact member through the linkage system, the motor moving the arm contact member to a target position to apply force to the depth regulating wheel arm.

[00127] Example 3 is a row unit according to any or all of the previous examples, wherein the linkage system comprises: a locking member that locks the arm contact member in the target position.

[00128] Example 4 is a row unit according to any or all of the preceding examples, wherein the locking member is configured to transmit force exerted by the depth adjusting wheel arm against the arm contact member to the frame. support, isolating the engine from the force exerted by the depth adjusting wheel arm against the arm contact member.

[00129] Example 5 is the row unit according to any or all of the preceding examples, wherein the locking member comprises: a self-locking worm drive including a worm screw and a screw gear without end.

[00130] Example 6 is the row unit according to any or all of the previous examples, wherein the motor includes a rotary motor output element.

[00131] Example 7 is the row unit according to any or all of the previous examples, wherein the linkage system comprises: a set of gears connecting the rotary motor output element to the worm screw.

[00132] Example 8 is a row unit according to any or all of the previous examples, wherein the engine comprises an electric motor.

[00133] Example 9 is a row unit according to any or all of the preceding examples, wherein the linkage system comprises: a rotating arm that is mounted for rotation about a point on the support frame and having a first end that engages with the worm gear in the self-locking worm drive and a second end that supports the arm contact member.

[00134] Example 10 is the row unit according to any or all of the previous examples, wherein the planting depth actuator assembly and the depth adjusting wheel arm are configured to exert a substantially constant force regardless of the position of the depth adjustment wheel.

[00135] Example 11 is the row unit according to any or all of the previous examples, wherein the depth adjuster wheel comprises a pair of depth adjuster wheels and wherein the depth adjuster wheel arm comprises a pair of depth gauge wheel arms, each depth gauge wheel arm on the pair of depth gauge wheel arms coupling a depth gauge wheel on the pair of depth gauge wheels to the support frame, and wherein the contact member arm comprises: a rocker member which is in contact with both of the depth adjusting wheels and wherein the linkage system supports the rocker member for rotational movement to accommodate independent movement of each of the depth adjusting wheel arms. depth through a predetermined range of motion.

[00136] Example 12 is a planting machine, comprising: a tow bar; and a plurality of row units coupled to the tow bar, each row unit comprising: a support frame; a double disc opener; a depth adjusting wheel; a depth adjusting wheel arm that couples the depth adjusting wheel to the support frame; and an automatic planting depth actuator assembly, coupled to the depth control wheel arm, which receives a planting depth signal generated based on a target planting depth, and applies a force to the depth control wheel arm to adjust a position of the depth adjustment wheel in relation to the double disc opener.

[00137] Example 13 is the planting machine according to any or all of the previous examples, wherein the automatic planting depth actuator assembly comprises: an arm contact member; a self-locking linkage system configured to lock the arm contact member in place so that the depth adjusting wheel arm is locked in the adjusted position; and a motor, coupled to the arm contact member through the linkage system, the motor moving the arm contact member to a target position to apply force to the depth regulating wheel arm.

[00138] Example 14 is the planting machine according to any or all of the preceding examples, wherein the motor includes a rotary motor output element and wherein the self-locking linkage system comprises: a screw drive without self-locking end that includes a worm screw and a worm gear; and a gear assembly connecting the rotary motor output element to the worm screw in the self-locking worm drive.

[00139] Example 15 is the planting machine according to any or all of the previous examples, wherein the self-locking linkage system comprises: a rotating arm that is mounted for rotation about a point on the support frame and having a first end that engages with the worm gear in the self-locking worm drive and a second end that supports the arm contact member.

[00140] Example 16 is the planting machine according to any or all of the previous examples, wherein the depth adjusting wheel comprises a pair of depth adjusting wheels and wherein the depth adjusting wheel arm comprises a pair of depth gauge wheel arms, each depth gauge wheel arm on the pair of depth gauge wheel arms coupling a depth gauge wheel on the pair of depth gauge wheels to the support frame and wherein the depth gauge contact member arm comprises: a rocker member which is in contact with both of the depth gauge wheels and wherein the self-locking linkage system supports the rocker member for rotational movement to accommodate independent movement of each of the gauge wheel arms depth through a predetermined range of motion.

[00141] Example 17 is a row unit in a planting machine, comprising: a support frame; a pit opener; a depth adjusting wheel; a depth adjusting wheel arm that couples the depth adjusting wheel to the support frame; an arm contact member; a system of connections; and an actuator, coupled to the arm contact member through the linkage system, the actuator receiving an actuation signal and automatically moving the arm contact member to a target position, to apply force to the control wheel arm. depth, based on the actuation signal.

[00142] Example 18 is the row unit according to any or all of the previous examples, wherein the linkage system comprises a locking member configured to transmit force exerted by the depth adjusting wheel arm against the contact member arm, to the support frame, isolating the actuator from the force exerted by the depth adjusting wheel arm against the arm contact member.

[00143] Example 19 is the row unit according to any or all of the preceding examples, wherein the locking member comprises: a self-locking worm drive including a worm screw and a screw gear without end.

[00144] Example 20 is the row unit according to any or all of the preceding examples, wherein the linkage system comprises: a rotating arm that is mounted for rotation about a point on the support frame and having a first end that engages with the worm gear in the self-locking worm drive and a second end that supports the arm contact member.

[00145] Although the matter has been described in language specific to structural characteristics and/or methodological acts, it should be understood that the matter defined in the attached claims is not necessarily limited to the specific characteristics or acts described above. Instead, the specific features and acts described above are described as exemplary ways of implementing the claims.

Claims (12)

1. Row unit (106) in a planting machine (100), which comprises: a support frame (104); a pit opener (114); a depth adjusting wheel (116); a depth adjusting wheel arm (148) that couples the depth adjusting wheel (116) to the support frame (104); and a planting depth actuator assembly (154) comprising: an arm contact member (150, 220); a connection system (180) having a locking member (212); an actuator (210), coupled to the arm contact member (150) through the linkage system (180), the actuator (210) moving the arm contact member (150, 220) to a target position, to apply force to the depth adjusting wheel arm (148); and wherein the locking member (212) locks the arm contact member (150, 220) in the target position and is configured to prevent the force exerted by the depth adjuster wheel arm (148) against the depth contact member (148) arm (150, 220) is applied to the actuator (210); and wherein the planting depth actuator assembly (154) receives a planting depth actuation signal generated based on a target planting depth, and selectively engages the depth regulating wheel arm (148), to apply a force to the depth adjusting wheel arm (148) for positioning the depth adjusting wheel (116) relative to the pit opener (114) to obtain the target planting depth; characterized by the fact that the locking member (212) prevents the force exerted by the depth adjusting wheel arm (148) against the arm contact member (150, 220), by isolating the actuator (210) from the force exerted by the depth adjusting wheel arm (148) against the arm contact member (150, 220). 2. Row unit (106) according to claim 1, characterized in that the locking member (212) comprises: a self-locking worm drive including a worm screw and a screw gear without end. 3. Row unit (106) according to claim 2, characterized in that the arm contact member (150, 220) comprises a threaded opening configured to allow a lead screw therethrough, wherein the member contact arm (150, 220) moves along the lead screw upon rotation of the screw drive. 4. Row unit (106) according to claim 2, characterized in that a motor includes a rotary actuator output element. 5. Row unit (106) according to claim 4, characterized by the fact that the connection system (180) comprises: a set of gears connecting the rotary actuator output element to the worm screw. 6. Row unit (106) according to claim 5, characterized in that the actuator (210) comprises an electric motor. 7. Row unit (106) according to claim 2, characterized in that the connection system (180) comprises: a rotating arm (222) which is mounted for rotation about a point (224) on the support frame (104) and having a first end (226) that engages with the worm gear in the self-locking worm drive and a second end that supports the arm contact member (220). 8. Row unit (106) according to claim 1, characterized by the fact that the planting depth actuator assembly (154) and the depth regulating wheel arm (148) are configured to exert a constant force regardless of the position of the depth adjustment wheel (116). 9. Row unit (106) according to claim 1, characterized in that the depth control wheel (116) comprises a pair of depth control wheels and wherein the depth control wheel arm (148) comprises a pair of depth adjuster wheel arms, each depth adjuster wheel arm (148) on the pair of depth adjuster wheel arms coupling a depth adjuster wheel (116) on the pair of depth adjuster wheels to the support (104), and wherein the arm contact member (150, 220) comprises: a rocker member (202) which is in contact with both depth regulating wheels (116) and wherein the linkage system ( 180) supports the rocker member (202) for rotational movement to accommodate independent movement of each of the depth adjusting wheel arms (148) through a predetermined range of motion, wherein the rocker member (202) is movable along the connection system (180). 10. Row unit (106) according to claim 1, characterized in that the arm contact member (150) is configured to contact the depth regulating wheel arm (148) and a mechanical stop . 11. Row unit (106) according to claim 1, characterized in that the actuator (210) receives an actuation signal and automatically moves the arm contact member (150, 220) to a target position along the linkage system (180), to apply force to the depth adjusting wheel arm (1448), based on the actuation signal. 12. Planting machine (100), characterized by the fact that it comprises: a tow bar; and a plurality of row units (106), as defined in any one of claims 1 to 11, coupled to the tow bar; and an automatic planting depth actuator assembly (154), coupled to the depth regulating wheel arm (148), which receives a planting depth signal generated based on a target planting depth, and applies a force to the planting arm (154). depth adjuster wheel (148) for adjusting a position of the depth adjuster wheel (116) relative to the double disc opener (114), the automatic planting depth actuator assembly (154) comprising: an arm contact member ( 150, 220) configured to contact the depth adjusting wheel arm (148); and a self-locking linkage system (180) configured to lock the arm contact member (150, 220) in place so that the depth adjusting wheel arm (148) is locked in the adjusted position.