Press wheel assembly for delicate seed planting and data acquisition for a seed planter

20210007273 ยท 2021-01-14

    Inventors

    Cpc classification

    International classification

    Abstract

    The press wheel has instrumentation associated therewith detecting a rolling of the wheel over a planted set. A computing device is connected to the instrumentation and to the speed monitoring device of the planter. The computing device determines spacings between planted sets. The data obtained is real-time data and is readily available to the operator of the planter so that the speed of the planter can be adjusted on the fly to maintain an ideal set spacing. The press wheel has a soft, smooth, flexible and stretchable rolling surface capable of deforming over a planted set and detecting an imprint of the planted set in the surface thereof, without damaging the planted set. A contact signature of the rolling of the press wheel over a planted set shows that the rolling on of the press wheel over a planted set is as smooth as the rolling away from the planted set.

    Claims

    1. A press wheel associated with a seed planter, comprising: a structure configured for generating a soft contact signature thereof with a planted set when rolling over said planted set, for preventing bruising said planted set; wherein said soft contact signature comprising an increasing pressure gradient between said press wheel and said planted set and a decreasing pressure gradient between said press wheel and said planted set, and wherein a graphical representation of said increasing pressure gradient is basically a mirror image of a graphical representation of said decreasing pressure gradient.

    2. The press wheel as claimed in claim 1, further comprising pressure detecting instrumentation associated therewith for detecting a rolling thereof over said planted set.

    3. The press wheel as claimed in claim 1, said structure comprising an inflated tire.

    4. The press wheel as claimed in claim 3, wherein said tire is a balloon-type low-profile tire having a flexible, soft and smooth rolling surface and inflexible shoulders and side walls.

    5. The press wheel as claimed in claim 4, wherein an inflation of said tire is a pressure between 1.5 psi and 3.5 psi.

    6. The press wheel as claimed in claim 1, wherein said contact signature comprises an exponential pressure increase, an exponential pressure drop, and an elliptical pressure transition between said pressure increase and said pressure drop.

    7. The press wheel as claimed in claim 2, further comprising a speed monitoring device and a computing device associated therewith, being connected to said instrumentation for determining a spacing between said planted sets.

    8. The press wheel as claimed in claim 3, wherein said inflated tire has a thin, soft, flexible and stretchable surface along a central circumferential region thereof and a thick and inflexible shoulders and side walls bordering said central circumferential region.

    9. The press wheel as claimed in claim 8 wherein said central circumferential portion being configured for contacting said planted set and making an imprint in said circumferential portion.

    10. The press wheel as claimed in claim 9, wherein said imprint has a oval-like shape.

    11. A method for rolling a press wheel over a planted set planted in a furrow, without bruising said planted set, comprising the steps of; rolling said press wheel over said planted set, and generating a contact surface between said press wheel and said planted set, wherein said step of generating a contact surface comprises; causing an increasing pressure gradient between said press wheel and said planted set during an approach-contact of said press wheel to said contact surface and a decreasing pressure gradient during a departure of said press wheel from said contact surface, and wherein a graphical representation of said increasing pressure gradient is basically a mirror image of a graphical representation of said decreasing pressure gradient.

    12. A method as claimed in claim 11, wherein, wherein said increasing pressure gradient comprising an exponential pressure increase portion, and an elliptical pressure increase portion.

    13. A method as claimed in claim 12, wherein, wherein said decreasing pressure gradient comprising an exponential pressure drop portion, and an elliptical pressure transition between said increasing pressure gradient and said decreasing pressure gradient.

    14. The method as claimed in claim 11, wherein said step of rolling comprises making an imprint of said planted set in a surface of said press wheel.

    15. The method as claimed in claim 14, wherein said step of making an imprint comprises making an oval-shaped imprint.

    16. The method as claimed in claim 11, wherein said step of rolling comprises tucking said planted set in a soil of said furrow.

    17. A press wheel associated with a seed planter for simultaneously checking a set roll in a planted set and for detecting a location of said planted set without bruising said planted set, comprising: a structure comprising a balloon-type low-profile tire having a thin, soft, flexible and stretchable rolling surface along a central circumferential region thereof and a thick and inflexible shoulders and side walls bordering said central circumferential region; said tire being inflated to a pressure between 1.5 psi and 3.5 psi; said structure being configured for simultaneously checking a movement of said planted set against a bottom surface of a furrow, tucking said planted set in the soil of said furrow and forming an oval-shaped imprint of said planted set in said rolling surface of said press wheel, without damaging said planted set; and said structure further comprising instrumentation associated therewith detecting a deformation of said rolling surface by said imprint.

    Description

    BRIEF DESCRIPTION OF THE DRAWINGS

    [0044] FIG. 1 is a partial side view of a potato set path and delivery under the forward half of a press wheel to reduce set roll, as built in the McCloskey planter;

    [0045] FIG. 2 is a partial side view of the preferred planter used to describe the press wheel according to a preferred embodiment, and its operation;

    [0046] FIG. 3 is a partial cross-section view the furrow made by the preferred planter and a front view of the press wheel according to a first preferred embodiment;

    [0047] FIG. 4 is an illustration of a press wheel rolling over a potato set;

    [0048] FIG. 5 is a cross section view of the press wheel in the first preferred embodiment, as seen along line 5 in FIG. 2;

    [0049] FIG. 6 is a partial cross-section view of a first alternate press wheel in the planter according to the preferred embodiment;

    [0050] FIG. 7 is a side view of a small seed planter;

    [0051] FIG. 8 is a front view of the preferred press wheel in the small seed planter;

    [0052] FIG. 9 illustrates a combination of a preferred furrow opening shoe and a press wheel combination, according to the second preferred embodiment;

    [0053] FIG. 10 is a bottom view of the preferred furrow opening shoe illustrated in FIG. 9;

    [0054] FIG. 11 is a cross-section of the preferred furrow formed by the opening shoe illustrated in FIG. 9 and FIG. 10;

    [0055] FIG. 12 is a diametrical cross-section of the press wheel according to the second preferred embodiment;

    [0056] FIG. 13 is a cross-section of the preferred furrow formed by the opening shoe illustrated in FIG. 9 and FIG. 10, and a partial profile of a press wheel according to the second preferred embodiment;

    [0057] FIG. 14 is front view of the press wheel according to the second preferred embodiment checking a set roll of a planted set;

    [0058] FIG. 15 is an enlarged partial view of the press wheel in FIG. 14; checking a set roll of a planted set;

    [0059] FIG. 16 is a partial perspective view of several planted sets in a furrow that has been left open, for the purpose of showing the aspect of the floor of the furrow after the sets have been planted and tucked in the soil of the furrow by the press wheel according to the second preferred embodiment;

    [0060] FIG. 17 is a partial view of typical set-contact signaturesof the pressure sensor in the press wheel according to the second preferred embodiment, as seen on a computer screen associated with the planter using the preferred press wheel;

    [0061] FIG. 18 is a plan view of the true-scale set-contact signatures illustrated in FIG. 17;

    [0062] FIG. 19 is a plan view of a same-scale as in FIG. 18, of a set-contact signatures with an over-inflated press wheel;

    [0063] FIG. 20 is an enlarged, single, typical contact signature between the press wheel according to the second preferred embodiment and a planted set;

    [0064] FIG. 21 is an enlarged, single, typical contact signature between an over-inflate press wheel and a planted set, as seen in detail circle 21 in FIG. 19;

    [0065] FIG. 22 is a typical imprint or contact surface between the press wheel and a planted set;

    [0066] FIG. 23 illustrates the elements of a graphical representation of the typical contact signature in FIG. 20, in association with a corresponding imprint of FIG. 22;

    [0067] FIG. 24 is a partial perspective view of optional instrumentation associated with the press wheel according to the preferred embodiments;

    [0068] FIG. 25 is a partial plan view of a double row furrow that can be advantageously planted using the planter according to the preferred embodiment.

    DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

    [0069] The drawings presented herein are presented for convenience to explain the functions of all the elements included in the preferred embodiment of the present invention. Elements and details that are obvious to the person skilled in the art may not have been illustrated. Conceptual sketches have been used to illustrate elements that would be readily understood in the light of the present disclosure. The drawings illustrating machine elements are not fabrication drawings, and should not be scaled.

    [0070] The planter used to explained the press wheels according to the first and second preferred embodiments of the present invention is also described in term of its operation and the function of its components. The physical dimensions, material types, and manufacturing tolerances are not provided because these details do not constitute the essence of the present invention and would be considered obvious to the skilled artisan having acquired the knowledge that is actually provided in the present document.

    [0071] Each drawing has been prepared to illustrate a general concept rather that an actual fabrication. Theses drawings were prepared in this format so that they can be extrapolated and easily applied to planters of seeds and sets other than potato sets.

    [0072] Referring to FIG. 1, the press wheel of the McCloskey planter is illustrated. The McCloskey planter is considered the most important advance in the art of reducing set roll when planting sets. In the McCloskey planter, a potato set 20 is released from a planter's delivery tower 22. The seed piece or set is deflected against a deflector 26 and projected into the forward shadow 28 of a press wheel 30 rolling over the set, for checking the rolling momentum of the set against the bottom surface of the furrow. The press wheel 30 is preferably mounted on arms and spring loaded against the soil at the bottom of the furrow.

    [0073] There are two preferred embodiments of press wheels used for delicate planting and data collection. The first preferred embodiment includes several variances. In the second preferred embodiment, the furrow opening shoe and the shape of the press wheel are closely associated to each other.

    [0074] Referring to FIG. 2, a partial view of a planter on which the preferred press wheels are used is presented. The seed planter has a relatively wide furrow opening shoe 40. The furrow opening shoe is made of a cutting edge 42, abrasive-resistant opening plates 44 bordering the cutting edge and wings 46 for widening and lapping the bottom surface of the furrow.

    [0075] The preferred shape of the furrow is illustrated by label 50 in FIG. 3. The set-receiving channel formed by the cutting edge of the opening shoe 40 is labelled as 42, and the lapped surfaces formed by the wings 46 of the opening shoe are labelled as 46. The preferred shape of the furrow is made of the set-receiving channel 42 formed between two lapped surfaces 46. The preferred shape 50 of the furrow has a smooth and even surface that can receive a potato seed piece or set 52. The bottom surface of a set-receiving channel 42, generally, is sufficiently hard to receive a set and supporting that set above the soil. The bottom surface of the set-receiving channel 42 is sufficiently hard so that a set in that furrow represents a detectable object when rolling a press wheel 54 over the surface of that furrow. In FIG. 3, the press wheel 54 has been lifted up the surface of the furrow for clarity. In use, the rolling surface 56 of the press wheel 54 preferably touches the surface of the lapped surfaces 46 over the entire width of these surfaces as can be understood from the illustration in FIG. 4.

    [0076] As can be understood from FIGS. 3 and 4, the width of the tire 70 on the press wheel 54 is a same dimension as the width of the furrow. As also can be understood, both sides of the press wheel 54 are supported over the lapped surfaces 46 of the furrow 50. The set-receiving channel 42 has a depth relative to the lapped surfaces 46 that is less than a general diameter of a small potato seed piece 52. When the press wheel rolls over a planted set 52, the planted set 52 protrudes above a level of the lapped surfaces 46, causes an imprint to be made in the rolling surface 56 of the wheel and represents a detectable object intersecting with the rolling surface 56 of the press wheel 54.

    [0077] Referring back to FIG. 2, the planter, has deflectors 60 to deflect the trajectories 62 of sets toward a region under the forward half of a press wheel 54. These deflectors 60 are mounted to the planter between the seed delivery tower 64, and the press wheel 54. The press wheel 54 is mounted between the seed delivery tower 64 and a pair of furrow closing discs 66. It will be appreciated that the seed delivery tower 64 has of a double column configuration, delivering sets side-by-side in an alternating mode. The potato sets are released in a left-right-left mode, to improve on the efficiency of the planter. For this reason, the deflectors 60 and trajectories 62 referred to above are plural. In this drawing, both deflectors and both trajectories are superimposed over each other.

    [0078] In the illustration of FIG. 2, it will be appreciated that both deflectors 60 are angled inward to project potato sets in a single row. This placement of the deflectors 60 is a standard mounting on a double column potato planter.

    Press Wheel According to the First Preferred Embodiment and its Variances

    [0079] The press wheel 54 according to the first preferred embodiment of the present invention has an inflated tire 70 thereon. The tire 70 is a balloon type tire and the inflation thereof is such that the surface thereof is flexible, soft and smooth. The degree of flexibility of the tire is such that the wheel 54 can roll over a set 52, flex and stretch to make an imprint 72 of the set in the surface 56 of the wheel without damaging the set. The press wheel 54 preferably has a support disc 74 on each side thereof, as can be seen in FIG. 4.

    [0080] Each of the support discs 74 has a relatively large thickness and contribute to supporting part of the weight of the press wheel 54 in use. Moreover, the press wheel is supported in large part by the lapped surfaces 46. The support discs 74 rolling in the side heaps 50 of the furrow and the rolling surface 56 of the press wheel rolling on the lapped surfaces 46 contribute to support the weight of the press wheel 54 and to prevent impacts of the press wheel against a planted set.

    [0081] Referring now to FIGS. 2 and 5, the press wheel 54 has pressure-detecting instrumentation 80 mounted therein. In the preferred embodiments, the pressure-detecting instrumentation 80 includes a connection 82 to the valve stem 84 of a tube 86 mounted inside the tire 70. It will be appreciated that a tubeless tire may also be used.

    [0082] The pressure-detecting instrumentation 80 is mounted inside a sealed compartment 88. This compartment 88 is preferably mounted to, or encased in the support disc 74 of the wheel 54. The pressure-detecting instrumentation 80 monitors the internal air pressure of the tire 70 through the connection 82 to the valve stem 84. The sensitivity of the instrumentation is sufficient to detect a set making an imprint 72 on the surface 56 of the press wheel 54 when the press wheel 54 rolls over that planted set.

    [0083] The pressure-detecting instrumentation 80 also include a transmitter to transmit a wireless signal to a receiver and a computer.

    [0084] In use, the wireless signal is transmitted to the computer which records every occurrence of the press wheel rolling over a set. This signal is associated with the speed of the planter, by the computer, to determine a real-time spacing between the sets.

    [0085] This real-time spacing of the sets can be used by an operator to regulate the speed of the planter, on the fly, to take advantage of good and dry soil condition, for example. This real-time spacing signals can also be used by an operator to reduce the speed of the planter when the spacing of planted sets starts to deviate from an ideal value. The real-time spacing can be used by an operator to operate a planter at its maximum performance at all times and under all field conditions. This set spacing data obviates the need for the conventional manual set-spacing verification method mentioned before.

    [0086] The seed planter used with the press wheels according to the preferred embodiments preferably has a global positioning system (GPS) transmitter/receiver 90 mounted thereon. The signal from this GPS 90 is advantageously added to the instrumentation mentioned above to compute other valuable data.

    [0087] In the planter used with the press wheels according to the preferred embodiments, an encoder 92 is mounted on the swing arm of the press wheel 54 to establish a relation between the lower surface of the press wheel 54 and the location of the GPS 90 on the machine. The information collected by the GPS system 90 is combined to the pressure signal mentioned above and to the speed of the planter to determine the X-Y-Z coordinates (longitudinal, lateral, and depth) of every seed planted.

    [0088] Referring now to FIG. 6 an alternate press wheel 100 is partly illustrated therein. This particular press wheel 100 has two inflatable chambers therein. The wheel has a tubeless tire 110 and a tube 112 mounted inside the tubeless tire 110. Both the tube 112 and the tire 110 are inflated such that a space 114 is maintained between the tube 112 and the inside surface of the tire 110. It will be appreciated that the tire 110 is also a balloon-type, flexible and stretchable tire as described before, capable of deforming over a set without bruising or damaging the set.

    [0089] The inside surface of the tire 110 has several strips 116 of flexible metallic foil bonded thereto. The outside surface of the tube has a flexible metallic coating 118 thereon. The metallic coating 118 and the foil strips 116 are electrically connected to a circuit inside a signal transmitting compartment 120 mounted to the support disc 74 of the wheel 100.

    [0090] When the press wheel 100 rolls over a set, the surface of the tire is deflected, causing one of the foil strips 116 to come in contact with the metallic coating 118 of the tube 112, and sending an electric signal to the signal transmitting instrumentation. This signal is recorder by a computer to record the placement of every set along and across the furrow.

    [0091] It will be appreciated that a number of other devices can also be used in association with a press wheel to determine the exact position of a seed in a furrow. As a first example, a position sensor 130 is mounted on one of the arms supporting the press wheel 132 such as illustrated in FIG. 7, to detect an upward displacement in the press wheel 132. This position sensor 130 may be a linear encoder or a pressurized cylinder in which a change in pressure can be measured.

    [0092] In an other alternate embodiment, the press wheel 132 as illustrated in FIG. 8 is relatively narrow wheel for use in planting small hard seeds such as corn and bean seeds. The wheel is preferably made of thin metal and hollow. A detectable pinging sound of the wheel 132 rolling over a seed is recorded and related to seed location. Alternatively, a vibration in the wheel can be detected and associated with seed location. In the example of FIG. 7, an encoder 134 is mounted to the arm supporting the press wheel 132 for associating an angular position of the wheel to every ping noise heard from the wheel, and for calculating seed spacing.

    [0093] In yet other examples, proximity detectors can be used in association with the press wheel; pressure sensitive mats such as those used in gait analysis can be used in a wrapped-around mode around the press wheel or immediately under the flexible outer layer of the tire 70 to record impacts of the wheel against seed pieces. When a gait analysis mat is used, it can be used with an encoder 134 on the press wheel axle to determine an exact set placement relative to the lowermost point on the wheel.

    [0094] The possibilities listed above represent only a few examples, as still other equipment can be used in association with a press wheel to detect the position of a set after a momentum of that set has been depleted.

    Press Wheel According to the Second Preferred Embodiment

    [0095] Referring now to FIGS. 9-23, the press wheel according to the second preferred embodiment will be described. The press wheel according to the second preferred embodiment has a profile that closely matches the profile of the furrow opening shoe 200. The furrow opening shoe 200 has a cutting edge 202, a pair of abrasive-resistant pads 204 positioned to form a seed-receiving channel 206 of a width D of about 2.5 inches and a depth E of about 1.0 to 1.5 inches. The furrow opening shoe 200 has a pair of abrasive-resistant lapping arms 208 positioned along the bottom of the shoe to form a pair of horizontal shelves 210 in the furrow, bordering the seed-receiving channel 206. Each of these horizontal shelves 210 has a width F of about 2.5 inches. Both shelves 210 define a furrow width of a dimension G of about 9 inches. Heaps of soil 212 are formed along both sides of the furrow, outside the shelves 210.

    [0096] The press wheel 220 according to the second preferred embodiment has a low profile tire 222 with a width G1 of about 7.5 inches, to loosely fit the width of the shelves 210 of the furrow. The press wheel 220 has a thickness H of about 3 inches. The preferred low profile tire 222 has thick, strong and inflexible shoulders 224 and side walls, and a thin, flexible and stretchable sole 226, extending around the circumference of the tire. The width F1 of the stiff shoulders 224 of the press wheel have a respective dimension of about 2-2.5 inches. The width D1 of the thin sole 226 is about 3 inches. The thin sole 226 is very flexible, and to a lesser degree stretchable.

    [0097] The press wheel 220 also has thick circular plates 228 enclosing the low profile tire 222. The diameter of the press wheel 220 is about 12-13 inches. The tire 224 as described herein is available from Bluefield Seeding Solutions Inc., in Whiltshire, Prince Edward Island, Canada.

    [0098] Referring to FIG. 13, the profile 220 of the press wheel 220 according to the second preferred embodiment is illustrated over the profile of a furrow, as is in use. It will be appreciated from the illustration that the strong shoulders 224 of the press wheel 220 roll over the lapped shelves 210 of the furrow, and that the flexible sole 226 rolls over the seed-receiving channel 206. It will also be appreciated that the thick circular discs 228 of the press wheel roll over and into the heaps 212 of the furrow.

    [0099] The supporting soil under the discs 228 and the shoulders 224 of the press wheel 220 contribute to supporting a major portion of the weight of the press wheel 220, so that the sole 226 of the wheel delicately rolls over sets in the seed-receiving channel 206. The arms 94 supporting the press wheel 220 can also be calibrated to add or subtract some of the pressure of the wheel 220 against the soil. One measure to determine if the press wheel is properly supported, is to operate the press wheel 220 without creating any wave in the soil ahead of the wheel 220.

    [0100] The press wheel according to the second preferred embodiment has low profile tire 222 thereon. The tire has a tube 230 therein, a width G and a height H. The thickness of the sole 226 of the tire is the thickness of a membrane to protect the tube 230. The press wheel has a total weight of about 72-74 pounds. The tube 230 is preferably inflated to a pressure between 1.5-3.5 psi. It has been found that a pressure above 3.5 psi produces set damage. A pressure below 1.5 psi makes it more difficult to detect an imprint being made in the tire. A pressure of about 2.5 psi has been found to be ideal.

    [0101] The downward weight applied by the press wheel against the soil of the furrow is about 75 lbs, to help the seed pieces being absorbed by the press wheel and to cause an imprint to be made in the tire. However most of this weight is absorbed by the support discs 228 riding in the side heaps 212 of the furrow and by the shoulders 224 of the press wheel riding on the lapped shelves 210 of the furrow. The press wheel rolls firm and steady on the lapped shelves 210 of the furrow and floats gently over the seed-receiving channel 206. As mentioned before, the press wheel rolls in the furrow without creating a wave of soil in front of the wheel. These details allows the press wheel 220 to ride over planted sets at high speed without damaging the sets and without missing a detection of a set.

    [0102] Referring now to FIGS. 14-15, the operation of the press wheel 220 will be explained. In use, the weight and rolling of the press wheel 220 causes the soil of the furrow to be displaced toward the centre of the furrow. The movement of soil fills the seed-receiving channel 206 around the planted sets 52, tucking the sets 52 into the seed-receiving channel 206. It has been observed that the seed pieces 52 are tucked in to one half or more of their sizes, leaving only the crown portions thereof protruding above the bottom of the furrow. The crown portion of each set 52 is large enough to cause a detectable imprint 240 in the tire 222 of the press wheel 220.

    [0103] FIG. 16 illustrates a typical bottom surface 242 of a furrow after planting, between the press wheel 220 and the closing discs 66. The distance between the press wheel 220 and the closing discs 66 being shown in a exaggerated manner, for clarity. The bottom surface 242 is relatively flat. The seed-receiving channel has been completely filled up. The seed pieces 52 have been partly buried and tucked in so that only the crown portion thereof protrude above the bottom surface 242 of the furrow.

    [0104] Because of the furrow opening shoe 200 and the press wheel 220 combination described herein, the movement of the planted set 52 are delicately checked; the planted set 52 are effectively tucked in; and the crown portion of every set 52 is large enough to make an imprint 240 in the press wheel 220. Typical high speed contact signatures 244 of detected imprints 240 by the press wheel 220 according to the second preferred embodiment can be seen in FIGS. 17-18.

    [0105] FIG. 17 illustrates true-scale press-wheel contact signatures observed during a planting run done at a set spacing of 12 inches and relatively high speed of 4 mph. The graph has been adjusted by algorithm to retain the contact signatures and ignore irrelevant noises and periods of silence.

    [0106] The contact signatures 244 of detected imprints 240 have common features. Referring to FIGS. 17 , 18, 20 and 23, it will be noticed that most signatures 244 have a common relatively wide base 246 or half-period, exponential pressure increase gradient 248, exponential pressure drop gradient 248, and an elliptical rise and fall portion 250 between the pressure increase and the pressure drop portions. The amplitude 252 of each signature 244 has a height that is 1 to 3 times as much as the width of the base 246 as is best illustrated in FIG. 20.

    [0107] It will be appreciated that the exponential pressure increase portion 248 is representative of a delicate initial approach-contact between the press wheel 220 and the seed piece 52. The common wide bases 246 or half-periods of the signatures indicate a relatively large and consistent contact duration between the press wheel 220 and the planted set 52. The elliptical rise and fall portion 250 indicates a gentle formation of an imprint 240 without sudden impact. The shape of these signatures 244 indicates that the contacts between the press wheel 220 and the seed pieces 52 are free of shock and high pressure point. The shape of the contact signatures 244 indicates a gradual approach-contact, a smooth formation of the imprint 240, a distinguishable signal of the contact of the press wheel with the planted set and a gradual withdrawal of the press wheel away from the planted set. During an attempt to determine a shape of the imprint using common carbon paper, the pressure of the press wheel over a planted set was insufficient to mark the planted set, the surface of the press wheel or the carbon paper itself. This is mentioned herein as a measure to fully appreciate the delicateness of the contact between the press wheel and a planted set.

    [0108] Referring now to FIG. 23, another common characteristic in the graphical representations of the contact signatures of FIGS. 17 and 18 will be explained. The graphical representations of the contact signatures 244 obtained in FIGS. 17-18, shows that the pressure increase portion 254 of each signature 244 is basically a mirror image of the pressure decrease portion 256, relative to a median line 258 of each signature 244. This phenomenon indicates an approach-contact of the press wheel over a planted set 52 that is as smooth as the departure of the press wheel from the planted set 52.

    [0109] Of course, potato seed pieces don't have a same diameter and shape. Therefore, in the planting run illustrated in FIGS. 17 and 18, the response signatures are not all the same. For example, responses 262 have a sharp pressure drop, that may have been caused by a seed piece 52 presenting only a sharp edge across the movement of the press wheel 220. In another example, double responses 264, could have been caused by a double seed drop or a seed and a clod, for example.

    [0110] Referring to FIG. 23, the exponential pressure increase and decrease portion 248, 248 of the contact signature 244 is caused by a rapid increase of the size of the imprint 240 in region 266 of the imprint 240. The elliptical portion 250 of the contact signature 244 is caused by a more gradual increase and decrease of the size of the imprint 240 in the region 268.

    [0111] As can be appreciated, the imprint 240 may have the shape of a circle or an oval. In this case, an oval imprint 240 fits the shape of the selected contact signature 244, because a signature for a circular imprint would have a taller exponential portion 248 and a shorter elliptical portion. Because of the curvature of the press wheel 220 in the circumferential direction, it is believed that the imprints 240 have oval shapes more often than circles. Such oval or circular contact surface or imprints 240 offers a better pressure distribution to avoid bruising the planted set. In the planting run illustrated in FIGS. 17 and 18, there is no straight-up-high-impact signature. All contact signatures 244 have consistent rise and fall over similar, relatively wide bases 246.

    [0112] The press wheel 220 according to the second preferred embodiment, its structure and its inflation as specified, makes it possible to obtain contact signatures of the quality illustrated, without bruising the potato seeds. This statement is enforced by showing in contrast, in FIGS. 19 and 21, a slight variation in the specified pressure and the consequences of the variation. The contact signatures as illustrated in FIGS. 19 and 21 were obtained with the press wheel 220 that was inflated to 5 psi. The signatures in FIG. 19 are illustrated at a same scale as those in FIGS. 17 and 18. However, it can be appreciated that at 5 psi, the tire has no flexion. The contact signatures 270 are made of straight up and straight down lines, indicating a sharp pressure point on the planted set. With these types of contact signatures 270, one can understand that the shock of the impact of the press wheel 220 rolling over a set is almost entirely absorbed by the planted set 52. Frequent bruising of planted sets were noticed at that pressure. Furthermore, the algorithm used in the graph of FIG. 17 has difficulties in distinguishing the planted sets when the tire pressure is that high. The contact signatures 270 are undistinguishable from machine and environment noises 272. The amplitudes of the signatures decrease as pressure increases above 3.5 psi.

    [0113] Referring now to FIG. 24, there is illustrated therein a seed planter with optional additional instrumentation. This optional instrumentation includes impact sensors 280, 280 mounted on the deflecting surfaces of the deflectors 60, 60. The impact sensors measure the force of the impact from a set bouncing off one of the deflectors. The optional instrumentation also a pressure sensor 80 as mentioned previously, and a GPS 90. The impact sensors 280, 280 are connected to a computer. The computer records the impacts of the sets against the deflectors, the impact forces of the sets, and the time of the impacts of the sets hitting each deflector 60, 60.

    [0114] The information obtained from the instrumentation mentioned herein above can be displayed on a monitor 282 to the operator of the planter in a format that indicates planter's performance. This information is also preferably transmitted to a main computer 284 in the farmer's office for example. Of course, the planter's performance data can also be displayed on a mobile communication device 284 using an app.

    [0115] The following data constitute a partial list of the information available from the instrumentation described above: [0116] to measure real-time seed spacing; [0117] to measure set roll consistency; [0118] to detect seed misses (empty release); [0119] to detect double seed releases; [0120] to calculate total seed weight planted; [0121] to determine locations of the seed pieces across the width of the furrow; [0122] to detect efficiency of the seed delivery tower and deflectors; [0123] to measure performance and consistency of the planter; [0124] to generate maps of seed locations; [0125] to generate maps of planting speeds; [0126] to generate maps showing the topography of a field. [0127] to generate seed density mapping relative to field slopes, hills and low ground regions; [0128] to control seed discharge for aesthetical planting; [0129] to calculate seeds left in the hopper; [0130] to construct virtual paths to be used by the sprayer or the harvester; [0131] to detect the level of soil compaction or soil density in seed beds where the sets are located; [0132] to control the release of seeds or sets, into specific locations, to achieve optimal growth.

    [0133] One possible application for the optional instrumentation described above is illustrated in FIG. 25. In this drawing, there is illustrated a plan view of a double row, or staggered planting method. In this application, both deflectors 60, 60 are oriented to deflect seeds in two spaced apart parallel rows. The longitudinal distance L as well as the lateral distance M between plants can be monitored to ensure that each plant has a minimum growth area N for minimizing tuber crowding.

    [0134] Modern seed planters can make a relatively large furrow with a smooth surfaced bottom. Although double row or staggered planting is not well known in the industry, it is believed that this method of planting has many advantages over the single row method. The planting potato seed pieces for example, in a staggered arrangement along a single row is made to respect an ideal foot print for each plant, while reducing the longitudinal spacing between adjacent plants. In some cases, the longitudinal spacing of planted sets along a furrow can be reduced by 30%, while maintaining the same foot print for each plant. The soil usage in a potato field is thereby improved. Yield per acre is also increased.

    [0135] It is believed that staggered planting will be more appreciated in the future, with the advance of precision agriculture and the use of press wheels on seed planters.

    [0136] Another benefit from the data obtained from this optional instrumentation include the matching of data collected from the planter with aerial images monitoring actual plant growth. Aerial images of a potato field during the plant growing season can be compared to maps of seed weight, seed piece spacings, seed placement accuracy, or maps of planting speeds, to associate plant growth to the best planting conditions. The information derived from this matching of maps can be used to formulate corrective actions for future planting. It is also believed that the data collected from the instrumentation mentioned herein will become more and more valuable as precision agriculture continues to progress.