Track system and method for assessing the need for an alignment correction

Abstract

A track system, which is selectively steerable about a steering axis, includes a frame, wheel assemblies and an endless track. A load borne by the track system defines a center of mass, a projection of the center of mass defining a first point of intersection on the ground surface. A projection of the steering axis defines a second point of intersection on the ground surface. The first point of intersection is located at a first longitudinal distance, and a first lateral distance from a lateral center plane and a longitudinal center plane, respectively. The second point of intersection is located at a second longitudinal distance and a second lateral distance from the lateral center plane and the longitudinal center plane, respectively. A difference between the first and second longitudinal distances defines a trail distance. A difference between the first and second lateral distances defining a scrub distance.

Description

TRACK SYSTEM AND METHOD FOR ASSESSING THE NEED FOR ANALIGNMENT CORRECTIONTECHNICAL FIELD

[0001] The present technology relates to track systems, more particularly to steerable track systems as well as methods for assessing the need for an alignment correction thereof.BACKGROUND

[0002] Certain vehicles, such as, for example, agricultural vehicles (e.g., harvesters, combines, tractors, agriculture implement, etc.) and construction vehicles (e.g., bulldozers, front-end loaders, etc.), are used to perform work on ground surfaces that are soft, slippery and / or uneven (e.g., soil, mud, sand, ice, snow, etc.).

[0003] Conventionally, such vehicles have had large wheels with tires to move the vehicle along the ground surface. Under some conditions, such tires may have poor traction on some ground surfaces and, as these vehicles are generally heavy, the tires may compact the ground surface in an undesirable way owing to the weight of the vehicle. As an example, when the vehicle is an agricultural vehicle, the tires may compact the soil in such a way as to undesirably inhibit the growth of crops. In order to reduce the aforementioned drawbacks, to increase traction and to distribute the weight of the vehicle over a larger area on the ground surface, track systems were developed to be used in place of at least some of the wheels and tires on the vehicles.

[0004] Vehicles equipped with such track systems typically have improved floatation and better traction, particularly when they are operated over soft and / or rough terrains. The improved floatation and traction are generally due to the larger ground-contacting area of the traction band. This larger ground-contacting area, commonly referred to as contact patch, effectively spreads the weight of the vehicle over a larger area (i.e. increased floatation) and provides additional ground-engaging surface to the vehicle (i.e. increased traction).

[0005] However, track systems are not without their shortcomings. Though the larger contact patch of the traction band is generally a significant advantage when the vehicle is operated over soft terrains (e.g. snow, mud, sand, etc.), the larger contact patch can become a hindrance when the vehicle is operated over harder surfaces (e.g. packed dirt, concrete, asphalt, pavement, etc.). Indeed, the larger contact patch generally implies more friction between the traction band and the ground, making the vehicle more difficult to steer and maneuver and ultimately negatively affecting its steering when operated over some surfaces.

[0006] However, despite some attempts to improve the steering of vehicles equipped with track systems, there is still a need for an improved track system assembly and / or steering assembly which will at least mitigate some shortcomings of prior art assemblies.SUMMARY

[0007] It is an object of the present technology to ameliorate at least some of the inconveniences present in the prior art.

[0008] According to one aspect of the present technology, there is provided a track system for a vehicle. The vehicle includes a steering assembly that defines a steering axis about which the track system is configured to selectively rotate. The track system includes a frame, a drive wheel assembly, at least one idler wheel assembly, at least one support wheel assembly, an endless track a lateral center plane and a longitudinal center plane. The drive wheel assembly is configured to operatively connect to the steering assembly. The at least one idler wheel assembly is rotationally connected to the frame. The at least one support wheel assembly is rotationally connected to the frame. The endless track is drivingly engaged to the drive wheel assembly, and is engaged to the at least one idler wheel assembly and to the at least one support wheel assembly. The endless track has a groundengaging segment configured to engage a ground surface. The at least one support wheel assembly distributes a load borne by the track system over the ground-engaging segment. The load defines a center of mass, and a projection of the center of mass defines a first point of intersection on the ground surface. The first point of intersection is located at a first longitudinal distance from the lateral center plane, and at a first lateral distance fromthe longitudinal center plane. A projection of the steering axis defines a second point of intersection on the ground surface, the second point of intersection being located at a second longitudinal distance from the lateral center plane, and at a second lateral distance from the longitudinal center plane. A difference between the first and second longitudinal distances defines a trail distance. A difference between the first and second lateral distances defines a scrub distance.

[0009] In some embodiments, the scrub distance is generally zero; and the second point of intersection is longitudinally rearward from the first point of intersection.

[0010] In some embodiments, the scrub distance is generally zero, and the second point of intersection is longitudinally forward from the first point of intersection.

[0011] In some embodiments, the second point of intersection is laterally outward from the first point of intersection, and the second point of intersection is longitudinally rearward from the first point of intersection.

[0012] In some embodiments, the second point of intersection is laterally outward from the first point of intersection, and the second point of intersection is longitudinally forward from the first point of intersection.

[0013] In some embodiments, the second point of intersection is laterally inward from the first point of intersection, and the first point of intersection is longitudinally rearward from the first point of intersection.

[0014] In some embodiments, the second point of intersection is laterally inward from the first point of intersection, and the second point of intersection is longitudinally forward from the first point of intersection.

[0015] In some embodiments, the first point of intersection is aligned with the longitudinal center plane or laterally offset from the longitudinal center plane.

[0016] In some embodiments, the drive wheel assembly is configured to be operatively connected to a driving shaft of the vehicle.

[0017] In some embodiments, the at least one idler wheel assembly also distributes the load borne by the track system over the ground-engaging segment.

[0018] In some embodiments, the frame includes a first frame member, and a second frame member connected to the first frame member about a pivot point. The pivot point is longitudinally forward from the lateral center plane causing the first point of intersection to be longitudinally closer to a front end of the ground-engaging segment than to a rear end of the ground-engaging segment.

[0019] In some embodiments, the first point of intersection is longitudinally forward from the second point of intersection, or longitudinally rearward from the second point of intersection.

[0020] In some embodiments, the frame includes a first frame member, and a second frame member connected to the first frame member about a pivot point, the pivot point being longitudinally rearward from the lateral center plane causing the first point of intersection to be longitudinally closer to a rear end of the ground-engaging segment than to a front end of the ground-engaging segment.

[0021] In some embodiments, the first point of intersection is longitudinally forward from the second point of intersection, or longitudinally rearward from the second point of intersection.

[0022] In some embodiments, the at least one idler wheel assembly is disposed at one of a front end of the track system and a rear end of the track system, and the at least one idler wheel assembly is in a predetermined position from the ground surface causing the first point of intersection to be closer to one of the front end of the track system and the rear end of the track system.

[0023] In some embodiments, the predetermined position is one of an elevated position relative to the ground surface, causing the first point of intersection to be closer to the one of the front end and the rear end opposite to the at least one idler wheel assembly, and a lowered positioned relative to the ground surface, causing the first point of intersection tobe closer to the one of the front end of the track system and the rear end of the at least one idler wheel assembly.

[0024] In some embodiments, the first point of intersection is longitudinally forward from the second point of intersection, or longitudinally rearward from the second point of intersection.

[0025] In some embodiments, the track system is asymmetrical about the lateral center plane thereby causing the first point of intersection to be closer to one longitudinal end of the track system.

[0026] In some embodiments, the first point of intersection is longitudinally forward from the second point of intersection, or longitudinally rearward from the second point of intersection.

[0027] In some embodiments, the at least one support wheel assembly includes a tandem wheel assembly disposed on at least one lateral side of the track system, thereby causing the first point of intersection to be closer to the one lateral side.

[0028] In some embodiments, the first point of intersection is laterally outward forward from the second point of intersection, or laterally inward from the second point of intersection.

[0029] In some embodiments, the steering axis is a first steering axis, and the track system further includes a steering knuckle configured to be operatively connected to the steering assembly. The steering knuckle provides a second steering axis, a projection of the second steering axis defining a third point of intersection on the ground surface, the third point of intersection being spaced from the second point of intersection, and the third point of intersection being located at a third longitudinal distance from the lateral center plane, and at a third lateral distance from the longitudinal center plane.

[0030] In some embodiments, a difference between the first and third longitudinal distances defines a second trail distance, a difference between the first and third lateral distances defines a second scrub distance, at least one of the second trail distance isdifferent from the first trail distance, and the second scrub distance is different from the first scrub distance.

[0031] In some embodiments, the steering knuckle is configured to replace at least one component of the steering assembly of the vehicle.

[0032] According to another aspect of the present technology, there is provided vehicle including a frame, a steering assembly supported by the frame, and a track system according to the above aspect or according to the above aspect and one or more of the above embodiments, the track system being operatively connected to the steering assembly.

[0033] In some embodiments, the steering assembly defines the first steering axis, and the track system further includes a steering knuckle configured to define a second steering axis, the second steering axis being oriented differently from the first steering axis.

[0034] According to another aspect of the present technology, there is provided a track system steerable about a steering axis, the track system includes a frame, a plurality of wheel assemblies rotationally connected to the frame, an endless track, a lateral center plane and a longitudinal center plane. The endless track surrounds the frame assembly and the plurality of wheel assemblies. The endless track has a ground-engaging segment configured to engage a ground surface. A load borne by the track system is distributed over the ground-engaging segment, the load defining a center of mass, a projection of the center of mass defining a first point of intersection on the ground surface. The first point of intersection is located at a first longitudinal distance from a lateral center plane of the track system, and at a first lateral distance from a longitudinal center plane of the track system. A projection of the steering axis defines a second point of intersection on the ground surface, the second point of intersection of the projection of the steering axis being located at a second longitudinal distance from the lateral center plane, and at a second lateral distance from the longitudinal center plane. A difference between the first and second longitudinal distances defining a trail distance. A difference between the first and second lateral distances defining a scrub distance.

[0035] In some embodiments, the scrub distance is generally zero, and the second point of intersection is longitudinally rearward from the first point of intersection.

[0036] In some embodiments, the scrub distance is generally zero, and the second point of intersection is longitudinally forward from the first point of intersection.

[0037] In some embodiments, the second point of intersection is laterally outward from the first point of intersection, and the second point of intersection is longitudinally rearward from the first point of intersection.

[0038] In some embodiments, the second point of intersection is laterally outward from the first point of intersection, and the second point of intersection is longitudinally forward from the first point of intersection.

[0039] In some embodiments, the second point of intersection is laterally inward from the first point of intersection, and the first point of intersection is longitudinally rearward from the first point of intersection.

[0040] In some embodiments, the second point of intersection is laterally inward from the first point of intersection, and the second point of intersection is longitudinally forward from the first point of intersection.

[0041] In some embodiments, the first point of intersection is aligned with the longitudinal center plane or laterally offset from the longitudinal center plane.

[0042] In some embodiments, the drive wheel assembly is configured to be operatively connected to a driving shaft of the vehicle.

[0043] In some embodiments, the at least one idler wheel assembly also distributes the load borne by the track system over the ground-engaging segment.

[0044] In some embodiments, the frame includes a first frame member, and a second frame member connected to the first frame member about a pivot point. The pivot point is longitudinally forward from the lateral center plane causing the first point of intersectionto be longitudinally closer to a front end of the ground-engaging segment than to a rear end of the ground-engaging segment.

[0045] In some embodiments, the first point of intersection is longitudinally forward from the second point of intersection, or longitudinally rearward from the second point of intersection.

[0046] In some embodiments, the frame includes a first frame member, and a second frame member connected to the first frame member about a pivot point. The pivot point is longitudinally rearward from the lateral center plane causing the first point of intersection to be longitudinally closer to a rear end of the ground-engaging segment than to a front end of the ground-engaging segment.

[0047] In some embodiments, the first point of intersection is longitudinally forward from the second point of intersection, or longitudinally rearward from the second point of intersection.

[0048] In some embodiments, the at least one idler wheel assembly is disposed at one of a front end of the track system and a rear end of the track system, and the at least one idler wheel assembly is in a predetermined position from the ground surface causing the first point of intersection to be closer to one of the front end of the track system and the rear end of the track system.

[0049] In some embodiments, the predetermined position is one of an elevated position relative to the ground surface, causing the first point of intersection to be closer to the one of the front end and the rear end opposite to the at least one idler wheel assembly, and a lowered positioned relative to the ground surface, causing the first point of intersection to be closer to the one of the front end of the track system and the rear end of the at least one idler wheel assembly.

[0050] In some embodiments, the first point of intersection is longitudinally forward from the second point of intersection, or longitudinally rearward from the second point of intersection.

[0051] In some embodiments, the track system is asymmetrical about the lateral center plane thereby causing the first point of intersection to be closer to one longitudinal end of the track system.

[0052] In some embodiments, the first point of intersection is longitudinally forward from the second point of intersection, or longitudinally rearward from the second point of intersection.

[0053] In some embodiments, the at least one support wheel assembly includes a tandem wheel assembly disposed on at least one lateral side of the track system, thereby causing the first point of intersection to be closer to the one lateral side.

[0054] In some embodiments, the first point of intersection is laterally outward forward from the second point of intersection, or laterally inward from the second point of intersection.

[0055] In some embodiments, the steering axis is a first steering axis, and the track system further includes a steering knuckle configured to be operatively connected to the steering assembly. The steering knuckle provides a second steering axis, a projection of the second steering axis defining a third point of intersection on the ground surface, the third point of intersection being spaced from the second point of intersection, and the third point of intersection being located at a third longitudinal distance from the lateral center plane, and at a third lateral distance from the longitudinal center plane.

[0056] In some embodiments, a difference between the first and third longitudinal distances defines a second trail distance, and a difference between the first and third lateral distances defines a second scrub distance. At least one of the second trail distance is different from the first trail distance, and the second scrub distance is different from the first scrub distance.

[0057] In some embodiments, the steering knuckle is configured to replace at least one component of the steering assembly of the vehicle.

[0058] According to another aspect of the present technology, there is provided a vehicle including a frame, a steering assembly supported by the frame, and a track system according to the above aspect or according to the above aspect and one or more of the above embodiments, the track system being operatively connected to the steering assembly.

[0059] In some embodiments, the steering assembly defines the first steering axis, and the track system further includes a steering knuckle configured to define a second steering axis, the second steering axis being oriented differently from the first steering axis.

[0060] According to another aspect of the present technology, there is provided a steering assembly for a track system. The track system defines a center of mass, and a projection of the center of mass defines a first point of intersection on the ground surface. The steering assembly includes a steering knuckle configured to operatively connect to a track system. The steering knuckle defines a steering axis, a projection of the steering axis defining a second point of intersection on the ground surface. The second point of intersection is one of longitudinally forward from the first point of intersection, and longitudinally rearward from the first point of intersection. The second point of intersection is one of laterally inward from first point of intersection, and laterally outward from first point of intersection.

[0061] In some embodiments, the scrub distance is generally zero, and the second point of intersection is longitudinally rearward from the first point of intersection.

[0062] According to another aspect of the present technology, there is provided a method for assessing the need for an alignment correction to an endless track of a track system connectable to a steering assembly of a vehicle. The method includes determining a total current deviation of the track system with the track system travelling in at least one of a forward direction, a backward direction, a left direction and a right direction, the total current deviation being caused by one or more of: i) a current position of a center of mass of the track system, ii) a current position of a point of intersection of a projection of a steering axis of the steering assembly with a ground surface; iii) a relative position between the current position of the center of mass, and i v) a loose between at least one of the steering assembly and the track system. The method also includes determining an effect of the total current deviation on a nominal alignment of the endless track of the track system. Theeffect of the total current deviation being greater than an acceptable pre-determined threshold indicates that an alignment correction to modify the nominal alignment of the endless track is required.

[0063] In the context of the present specification, unless expressly provided otherwise, the words "first''', “ second' , “third / etc. have been used as adjectives only for the purpose of allowing for distinction between the nouns that they modify from one another, and not for the purpose of describing any particular relationship between those nouns.

[0064] It must be noted that, as used in this specification and the appended claims, the singular form “a”, ‘ W’ and “the” include plural referents unless the context clearly dictates otherwise.

[0065] As used herein, the term “about” in the context of a given value or range refers to a value or range that is within 20%, preferably within 10%, and more preferably within 5% of the given value or range.

[0066] As used herein, the term “and'or” is to be taken as specific disclosure of each of the two specified features or components with or without the other. For example, “A and / or B” is to be taken as specific disclosure of each of (i) A, (ii) B and (iii) A and B, just as if each is set out individually herein.

[0067] For purposes of the present application, terms related to spatial orientation when referring to a track system and components in relation thereto, such as “vertical”, “horizontal / “forwardly” , “rearwardly” , “left / “right / “above” and “below”, are, with respect to the track system, as they would be understood by a driver of a vehicle to which the track system is connected, in which the driver is sitting on the vehicle in an upright driving position, with the vehicle steered straight-ahead and being at rest on flat, level ground.

[0068] Implementations of the present technology each have at least one of the above- mentioned objects and / or aspects, but do not necessarily have all of them. It should be understood that some aspects of the present technology that have resulted from attemptingto attain the above-mentioned object may not satisfy this object and / or may satisfy other objects not specifically recited herein.

[0069] Additional and / or alternative features, aspects, and advantages of implementations of the present technology will become apparent from the following description and the accompanying drawings.BRIEF DESCRIPTION OF THE DRAWINGS

[0070] For a better understanding of the present technology, as well as other aspects and further features thereof, reference is made to the following description which is to be used in conjunction with the accompanying drawings, where:

[0071] Figure 1A is a perspective view of a vehicle with track systems according to embodiments of the present technology;

[0072] Figure IB is a partially exploded perspective view of the vehicle of Figure 1;

[0073] Figure 2 is a perspective view of one of the track systems of Figure 1;

[0074] Figure 3A is a schematic top view of the track system of Figure 2;

[0075] Figures 3B, 3C, and 3D are schematic top views of the track system of Figure 2 with some misalignment;

[0076] Figure 3E is a schematic top plan view of an unpowered track system travelling in a forward direction;

[0077] Figures 3F and 3G are schematic top plan views of the unpowered track systems of Figure 3E travelling in the forward direction, and having some misalignment;

[0078] Figure 3H is a schematic top plan view of a powered track system travelling in a forward direction;

[0079] Figures 31 and 3J are schematic top plan views of the powered track systems of Figure 3H travelling in the forward direction, and having some misalignment;

[0080] Figure 3K is a schematic top plan view of a track system with potential intersections between a projection of a steering axis with a ground surface;

[0081] Figures 3L and 3M are schematic top plan views of a track system subjected to various forces;

[0082] Figure 4A is a schematic side view of a track system with an intersection between a projection of a steering axis and a ground surface being at a center position;

[0083] Figure 4B is a schematic top plan view of the track system of Figure 4A;

[0084] Figure 4C is a schematic cross-sectional view of the track system of Figure 4A taken along line AA;

[0085] Figures 4D and 4E are schematic views depicting the track system of Figure 4A undergoing a left turn;

[0086] Figure 5A is a schematic side view of a track system with an intersection between a projection of a steering axis and a ground surface being rearward from a center of mass;

[0087] Figures 5B, 5C, 5D, and 5E are schematic views of the track system of Figure 5A with the intersection between a projection of a steering axis and a ground surface being in a position A;

[0088] Figures 6A, 6B, 6C, 6D, 6E, and 6F are schematic views of the track system of Figure 5 A with the intersection between a projection of a steering axis and a ground surface being in a position B;

[0089] Figure 7A is a schematic side view of a track system with an intersection between a projection of a steering axis and a ground surface being forward from a center of mass;

[0090] Figures 7B, 7C, 7D, and 7E are schematic views of the track system of Figure 7A with the intersection between a projection of a steering axis and a ground surface being in a position D;

[0091] Figures 8A, 8B, 8C, 8D, 8E, and 8F are schematic views of the track system of Figure 7A with the intersection between a projection of a steering axis and a ground surface being in a position E;

[0092] Figures 9A, 9B, and 9C are depictions of track systems known in the art; and

[0093] Figure 10A and 10B are depictions of track systems known in the art.DETAILED DESCRIPTION

[0094] The present disclosure is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the drawings. The disclosure is capable of other embodiments and of being practiced or of being carried out in various ways. Also, the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of “including” , “comprising”, or “having", “containing”, “involving" and variations thereof herein, is meant to encompass the items listed thereafter as well as, optionally, additional items. In the following description, the same numerical references refer to similar elements.

[0095] A track system 40 according to an embodiment of the present technology will be described in relation to a vehicle 60. It is to be understood that the track system 40 is merely an embodiment of the present technology. Thus, the description thereof that follows is intended to be only a description of illustrative examples of the present technology. This description is not intended to define the scope or set forth the bounds of the present technology. In some cases, what are believed to be helpful examples of modifications or alternatives to the track system 40 may also be set forth below. This is done merely as an aid to understanding, and, again, not to define the scope or set forth the bounds of the present technology. These modifications are not an exhaustive list, and, as a person skilled in the art would understand, other modifications are likely possible. Further, where this has not been done (i.e. where no examples of modifications have been set forth), it should not be interpreted that no modifications are possible and / or that what is described is the sole manner of implementing or embodying that element of the present technology. As a person skilled in the art would understand, this is likely not the case. In addition, it is to beunderstood that the track system 40 may be provided, in certain aspects, a simple embodiment of the present technology, and that where such is the case it has been presented in this manner as an aid to understanding. As a person skilled in the art would understand, various embodiments of the present technology may be of a greater complexity than what is described herein.

[0096] Referring to Figures 1A and IB, the vehicle 60 is schematically shown as an agricultural vehicle. However, it is contemplated that the vehicle 60 could be another type of vehicle. The vehicle 60 includes a chassis 62 that supports the various components of the vehicle 60. The vehicle 60 further includes shafts 68, 68’ extending laterally outwardly from the chassis 62. As will be described below, the shafts 68, 68’ may be driving shafts or non-driving shafts. The vehicle 60 also includes track systems 40, 40’, 40”, 40’”. Each one of the track systems 40, 40’ is connected to its respective shaft 68, and each one of the track systems 40”, 40’” is connected to its respective shaft 68’. In addition, it is contemplated that one or more of the track systems 40, 40’, 40”, 40’” could be connected to the chassis 62 of the vehicle 60 differently. For example, the track system 40 could be connected to the vehicle 60 via a pivot in addition to the shaft 68. In some cases, the track systems 40, 40’, 40”, 40’” have replaced wheels of the vehicle 60, where the vehicle was originally designed for and supplied with wheels. In the present embodiment, the front track systems 40, 40’ are operatively connected to a steering assembly 200 of the vehicle 60 and may thus referred to as steerable track systems 40, 40’. It is contemplated that the present technology and methods can be applicable to non-steerable track systems in some cases.

[0097] In the context of the following description, “outward” or “outwardly” means away from a longitudinal center plane of the chassis 62 of the vehicle 60, and “inward" or “inwardly” means toward the longitudinal center plane. In addition, in the context of the following description, “longitudinal” or “longitudinally” means in a direction (“X”) parallel to the longitudinal center plane of the chassis 62 of the vehicle 60 in a plane parallel to flat level ground, “lateral” or “laterally” means in a direction (“Y”) perpendicular to the longitudinal center plane in a plane parallel to flat level ground, and “vertical” or“vertzcrzZ / y” means in a direction (“Z”) perpendicular to the longitudinal center plane along a height direction of the track system 40 in a plane perpendicular to flat level ground.

[0098] In the context of the present technology, the term “axis” may be used to indicate an axis of rotation, or the term may refer to a “pivot joint” that includes all the necessary structure (bearing structures, pins, axles and other components) to permit a structure to pivot about such axis, as the case may be.

[0099] The direction of forward travel of the vehicle 60 and the track system 40 is indicated by an arrow 80. In the following description and accompanying Figures, the track system 40 is connected to a front, left side of the chassis 62 of the vehicle 60.

[0100] Furthermore, it is to be understood in the present description that a wheel assembly includes one or more wheels, an axle for supporting the one or more wheels, and the components (bearings, seals, etc.) that are necessary for the wheel(s) to rotate. As such, the different wheel assemblies will not be described in detail in the current description. Moreover, the expression “at least indirectly connected” is understood to mean that a component may be connected to another component via one or more intermediate structures or members, and that these intermediate structures are not necessarily described in the current description.Track System

[0101] Referring to Figure 2, the track system 40 will be generally described. The track system 40 has a frame 10 connected at least indirectly to the steering assembly 200 of the vehicle 60. In some embodiments, the frame 10 could be a single frame member. In other embodiments, the frame 10 could be two or more members such that the frame 10 may be referred to as a frame assembly. Although the track system 40 is described as a steerable track system, it is contemplated that in some embodiments, the track system 40 may not be connected to a steering assembly.Wheel Assemblies

[0102] The track system 40 includes leading and trailing idler wheel assemblies 121, 12t are at least indirectly connected to the frame 10. More particularly, the leading idler wheel assembly 121 is connected to the frame 10 via a tensioner assembly (not shown). The tensioner assembly is adapted to move the leading idler wheel assembly 121 longitudinally forward and backward in order to modulate tension in an endless track 20 of the track system 40. In some embodiments, the tensioner assembly may be configured to move the leading idler wheel assembly 121 vertically relative to a ground surface on which the track system 40 is rolling.

[0103] The track system 40 further has support wheel assemblies 14. The support wheel assemblies 14 may also be referred to as road wheel assemblies or roller wheel assemblies. The support wheel assemblies 14 are disposed intermediate to the leading idler wheel assembly 121 and the trailing idler wheel assembly 12t.

[0104] It is contemplated that in some instances, the idler wheel assemblies 121, 12t may be referred to as support wheel assemblies.

[0105] The support wheel assemblies 14, and sometimes the idler wheel assemblies 121, 12t in some cases) distribute a load borne by the track system 40 over a groundengaging segment 21 of the endless track 20. The load borne by the track system 40 includes the weight of the track system 40 and some of the weight of the vehicle 60.Drive Wheel Assembly

[0106] Referring to Figures 1A, IB and 2, the track system 40 further has a drive wheel assembly 16 drivingly engaged to the endless track 20. The drive wheel assembly 16 is at least indirectly connected to the steering assembly 200 that is operatively connected to the shaft 68 of the vehicle 60. In some cases, the shaft 68 is a driving shaft (i.e. operatively connected to an motor of the vehicle 60, and transmits torque and power necessary for driving the drive wheel 16, which in turn drives the endless track 20. In such cases, the vehicle 60 is a 4x4 vehicle, such that the shafts 68, 68' are operatively connected to the motor via a transmission (not shown) for driving the steerable track systems 40, 40’ and the track systems 40”, 40”’, respectively.Endless Track

[0107] The endless track 20 extends around the frame 10, the leading idler wheel assembly 121, the trailing idler wheel assembly 12t, and the support wheel assemblies 14. The endless track 20 is drivingly engaged to the drive wheel assembly 16, and is engaged to the leading idler wheel assembly 121, the trailing idler wheel assembly 12t, and the support wheel assemblies 14. The endless track 20 is an endless polymeric track. The endless track 20 has an inner surface engaging the leading idler wheel assembly 121, the trailing idler wheel assembly 12t, the support wheel assemblies 14 and the drive wheel 16. Lugs 24 are disposed on the inner surface, and are configured to drivingly engage with the drive 16. The endless track 20 also has an outer surface with a tread selected for ground engagement. The tread can vary from one embodiment to another according to the type of vehicle on which the track system 40 is to be used with and / or the type of ground surface on which the vehicle is destined to travel. It is contemplated that within the scope of the present technology, the endless track 20 may be constructed of a wide variety of materials and structures including metallic components.Frame

[0108] Referring to Figure 2, the frame 10 will now be described in more detail. In some cases, the frame 10 may include a single frame member. In other embodiments, the frame 10 may include two or more frame members, and therefore may be referred to as a frame assembly 10. The frame 10 defines an aperture (not shown) sized and dimensioned for receiving a pivot pin that extends laterally outwardly from the chassis 62 of the vehicle 60. It is contemplated that the pivot pin may extend laterally outwardly from another part besides the chassis 62. Thus, when the track system 40 is connected to the vehicle 60 via the pivot pin, the frame 10 is pivotally connected to the chassis 62 of the vehicle 60, such that when the vehicle 60 travels on a slopped terrain or travels over an obstacle, the track system 40 can pitch positively or negatively about a pivot axis defined by the pivot pin to conform to the terrain. In other embodiments, the frame 10 may include an upper frame member and a lower frame member pivotally connected to one another via a pivot pin thatextends laterally. Thus, when the vehicle 60 travels on a slopped terrain, the lower frame member can pitch positively or negatively about the pivot axis to conform to the terrain.

[0109] The track system 40 bears part of the weight of the vehicle 60. Part of the weight of the vehicle is transmitted to the track system 40 via at least one of the drive wheel assembly and the pivot pin. The load borne by the track system 40 is transmitted to the support wheel assemblies 202, and then to a ground-engaging segment 21 of the endless track 20. In some embodiments, depending on the position of the idler wheels 1201, 120t and / or depending on the soil condition, they can also transmit load to the ground-engaging segment 21 of the endless track 20 (thereby increasing the size of the ground-engaging segment 21.Steering Knuckle

[0110] As best shown in Figure 2B, the track system 40 includes a steering knuckle 100. The steering knuckle 100 is connected to the steering assembly 200 for steering the steerable track system 40. The steering knuckle 100 is sized and structured to support a portion of the weight of the vehicle 60. In some embodiments, the shaft 68 does not bear a material portion of the weight of the vehicle 60.

[0111] The steering knuckle 100 is operatively and pivotally connected to the steering assembly 200 of the vehicle 60 to pivot about a steering axis 102 to allow for steering of the track system 40. As will be described in further detail below, the steering axis 102 is oriented to extend generally offset from a vertical plane so as to provide stability and / or maneuverability to the vehicle 60. The orientation may depend on the particular vehicle to which the track system 40 is configured to connect to, which impacts performance of the track system 40.

[0112] The steering knuckle 100 is pivotably connected to the steering assembly 200 via a kingpin assembly 110. The kingpin assembly 110 typically extends through an aperture defined in the steering knuckle 100. It is contemplated that the steering knuckle 100 and / or the track system 40 may be connected to the steering assembly 200 differently.For example, the track system 40 may be connected to the steering assembly 200 without the steering knuckle 100.

[0113] In some cases, the steering knuckle 100 is configured to replace an original steering knuckle and an original wheel hub of the vehicle 60. More specifically, in some instances, the vehicle 60 may originally be provided with wheels (instead of track systems). The steering knuckle 100 may be configured to accommodate in part for the replacement of the wheels with track systems. In other embodiments, the vehicle 60 may be designed to be manufactured with the steerable track systems 40.

[0114] The steering knuckle 100 may be similar to the ones described in U.S. Patent No. 10,343,732, in U.S. Patent No. 9,505,432, U.S. Patent No. 11,772,702, U.S. Patent Application No. 20240025477, all of which are incorporated by reference herein in their entirety.Center of Mass, Projection of Center of Mass, Steering Axis and Projection of Steering Axis

[0115] Referring to Figure 3 A, the track system 40 has a longitudinal center planeL and a transversal center plane T. The transversal center plane T may be referred to as a lateral center plane. The longitudinal center plane L and the transversal center plane T schematically divide the track system 40 in four quadrants: QI, Q2, Q3 and Q4. It is contemplated that the four quadrants may be named differently. QI and Q4 define a laterally inward side, labelled as « IN » in the accompanying Figures, of the track system 40. Q2 and Q3 define a laterally outward side, labelled as « OUT » in the accompanying Figures of the track system 40. QI and Q2 define a forward side, labelled as « FRONT » in Figure 3A of the track system 40. Q3 and Q4 define a rearward side, labelled as « BACK » in Figure 3A of the track system 40.

[0116] The track system 40 has a center of mass CoM. The center of mass CoM includes a portion of the mass of the vehicle 60 as well as a mass of the track system 40. The center of mass CoM represents the load borne by the track system 40 over the groundengaging segment 21 of the endless track 20. The center of mass CoM is positioned at agiven vertical distance from the ground surface. A projection of the center of mass CoM, which projects vertically, defines an intersection point CoM on the ground surface. In Figure 3A, the center of mass CoM and the intersection point CoM are aligned. In some instances, it can be said that the projection of the center of mass CoM defines an intersection point on the ground-engaging segment 21.

[0117] As will be described below, depending on various configurations of the track system 40, such as, for example, the presence of the pivot pin or the position of at least one idler wheel assembly, the position of the center of mass CoM may vary. In the illustrated embodiment, the center of mass CoM is laterally aligned with the longitudinal center plane L, but longitudinally rearward from the transversal center plane T. It is contemplated that in other embodiments, the center of mass CoM may be laterally offset from the longitudinal center plane L and / or may be longitudinally offset from the transversal center plane T.

[0118] For instance, in an embodiment where the track system 40 includes a pivot pin between upper and lower frame members, the center of mass CoM may be vertically under the pivot pin and projected to the ground-engaging segment 21 of the endless track 20 instead of being vertically under the drive wheel 16 or vertically under the center of mass of the overall track system 40, as described in U.S. Patent No. 7,712,557, the entirety of which is incorporated by reference herein.

[0119] The track system 40 is, as mentioned above, operatively connected to the steering assembly 100, which provides the kingpin assembly 110, and which defines the steering axis 102. The track system 40 is selectively steerable about the steering axis 102 by applying a torque S via the steering assembly 200. For example, the torque S could be applied inwardly (towards the vehicle 60), outwardly (away from the vehicle 60) or straight forward / backward (generally aligned with the longitudinal direction of the vehicle).

[0120] A projection of the steering axis 102 defines an intersection point P on the ground surface. In some instances, it can be said that the projection of the steering axis 102 may define an intersection point on the ground-engaging segment 21. In the illustratedembodiment, the point of intersection P is generally aligned with the longitudinal center plane L and the transversal center planes T.

[0121] As will be described below, position of the intersection point CoM, position of the intersection point P and relative position between the intersection point CoM and the intersection point P can vary.Presence of loose within the assembly

[0122] Referring to Figure 3B in some cases, there is a « play » (i.e., a loose) within the steering assembly 200 and / or within the track system 40 which makes the track system 40 rotate or oscillate around the steering axis of an angle y.

[0123] It is understood that this loose can come from the manufacturing tolerances and / or wear of some components of these assemblies. Over time, wear can increase the loose and therefore the angle y can increase as well.

[0124] In some cases, the loose can be generally evenly distributed between the inward and outward sides of the track system 40 so that the angle y can be divided in two generally equal inward and outward angles, y in, y out, respectively.

[0125] In some cases, the loose can be generally unevenly distributed between the inward and outward sides of the track system 40 so that the angle y can be divided in two generally unequal inward and outward angles, where one of the inward and outward angles is greater than the other.

[0126] In the present embodiment, except specified otherwise, the track system 40 is hypothetically generally aligned with the longitudinal center plane L when operated forward / backward in straight line (direction 80).

[0127] ml schematically represents the track system 40 when rotated inwardly due to the loose in the inward direction and m2 schematically represents the track system 40 when rotated outwardly due to the loose in the outward direction.

[0128] As will be further described, the loose can have an impact on the behaviour of the track system and the alignment of its endless track.

[0129] As best seen in Figure 3C, when the track system 40 is rotated inwardly due to the loose (a> 1), the center of mass CoM is moved laterally of a distance Dout proportional to the magnitude of loose in the inward direction (angle y in).

[0130] Similarly, as best seen on FIG. 3D (top view, X-Y plane), when the track system 40 is rotated outwardly due to the loose (m2), the center of mass CoM is moved laterally of a distance Din proportional to the magnitude of loose in the outward direction (angle y out).

[0131] Typically, once the track system 40 is rotated inwardly or outwardly due to the loose (ml, m2, respectively), the track system 40 generally tends to keep this rotated or deviated orientation until an additional event occurs, such as a left or right turn, or overcoming of an obstacle for examples. In other words, even if the steering assembly is aligned with the forward / backward direction (and thus the drive wheel 16 operatively connected thereto), the track system 40 - or at least some components of it - can be biases inwardly or outwardly due to the loose in these directions. This can contribute in premature wear of certain components of the track system and / or of the steering assembly in some cases. In other cases, this can make the alignment of the endless track 20 difficult.Difference Between a Powered Track System and an Unpowered Track System

[0132] Referring to Figures 3E, 3F and 3G, without being bound by any theory, when the track system 40 is travelling in a forward direction, a force F is generated and applied to the center of mass CoM. In some cases, the force F includes at least one of a friction force resulting from the engagement of the ground and the endless track 20, a rolling resistance of the track system 40 and its components, and a driving force generated by the shaft 68 which transmits torque and power to the drive wheel assembly 16.

[0133] The magnitude of the force F can depend on various factors such as acceleration variation, variation of traction effort, variation of rolling resistance. A lateral force resulting from the friction of the endless track 20 against the ground surface, wherethe friction force is shown in the Figures with an arrow identified FRICTION, can oppose the steering operation of the track system 40. The force F and the lateral friction force each generate a torque around the intersection point P. It is contemplated that a torque generated by the force F is generally greater than a torque generated by the lateral force FRICTION. It is contemplated that the lateral force FRICTION can be greater than at least the torque generated by the loose (ML). In some cases, the torque Mf can generally help to stabilize the track system when it is operated in forwardly or backward directions. In some cases, the magnitude of the force F can be immaterial.Unpowered Track System

[0134] Referring to Figures 3E to 3G, in cases where the shaft 68 is a non-driving shaft, such that torque and power are not transmitted to the drive wheel assembly 16, the track system 40 is an « unpowered » track system. In such cases, the force F is typically directed in the direction opposite to where the vehicle 60 is going, as best seen on Figure 3E.

[0135] As mentioned previously, in some cases, the loose can rotate the track system 40 inwardly (FIGS. 3C and 3F), which moves the center of mass laterally of a distance Dout proportional to the magnitude of loose in the inward direction (angle yin). This creates an offset of the force F that generates a torque (ML) that is counter-clockwise around the point of intersection P of the steering axis 102. This generally makes the track system 40 being pointing outwardly (toe-out) initially, but when the vehicle 60 is travelling in forward direction the torque (ML) generally straightens the track system (self-centering effect).

[0136] Similarly, as mentioned previously, in some cases, the loose can rotate the track system 40 outwardly (FIGS. 3D and 3G), which moves the center of mass laterally of a distance Din proportional to the magnitude of loose in the outward direction (angle gout). This creates an offset of the force F that generates a torque (ML) that is clockwise around the point of intersection of the steering axis (P). This generally makes the track system 40 being pointing inwardly (toe-in) initially, but when the vehicle 60 is travellingin forward direction the torque (ML) generally straightens the track system (self-centering effect).Powered Track System

[0137] Referring to Figures 3H to 3J, when the shaft 68 is a driving shaft that provides torque and power to the drive wheel assembly 16, the track system 40 is a « powered » track system. In these cases, the force F is typically directed in the same direction that the vehicle 60 is travelling, as best seen in Figure 3H. While opposing forces such as friction forces or rolling resistance are still present, the driving force provided to the drive wheel assembly 16 overcomes them in order to propel the vehicle 60 in a given direction (e g., forward or backward). In some cases, track systems can be temporarily considered as “powered” and transitioned to “unpowered” (e.g., with or without under tractive effort, with or without acceleration, at or not at constant velocity, etc.).

[0138] As mentioned previously, in some cases, the loose can rotate the track system 40 inwardly (Figures 3C and 31), which moves the center of mass laterally of a distance Dout proportional to the magnitude of loose in the inward direction (angle yin). This creates an offset of the force F that generates a torque ML that is clockwise around the point of intersection P of the steering axis 102. This generally makes the track system 40 being pointing inwardly (toe-in) initially, but when the vehicle 60 is travelling in forward direction the torque (ML) generally does not straighten the track system (not self- centering effect).

[0139] Similarly, as mentioned previously, in some cases, the loose can rotate the track system 40 outwardly (Figures 3D and 31), which moves the center of mass laterally of a distance Din proportional to the magnitude of loose in the outward direction (angle yout). This creates an offset of the force F that generates a torque ML that is counterclockwise around the point of intersection P of the steering axis 102. This generally makes the track system 40 being pointing outwardly (toe-out) initially, but when the vehicle 60 is travelling in forward direction the torque ML generally does not straighten the track system (not self-centering effect).

[0140] It is understood that, the greater the loose within the assembly, the greater is the deviation (toe-in / toe-out) of the track system 40 relative to the vehicle 60 when the vehicle 60 travels in a forward / backward direction. This deviation (toe-in / toe-out) can contribute in premature wear of some components of the track system 40 and / or of the steering assembly 100 of the vehicle 60 in some cases. It also can have an impact on the method of aligning the endless track 20 of the track system 40 and / or the difficulty to achieve and maintain an alignment of said endless track 20 over time.

[0141] As will be further described below, the present technology addresses this issue to minimize its detrimental effect on the performance and durability of the track system 40.Different Positions of the Point of Intersection

[0142] In some cases, the intersection point P may be centered or offset with the longitudinal center plane L and / or with the transversal center plane T. This is common, notably, when a vehicle that was originally designed as a wheeled vehicle has undergone a modification to replace the original wheels with track systems. In other instances, a modification of the suspension system and / or wear of parts such as the steering assembly 200 and / or of the suspension system may change the position of the point of intersection P. In yet other instances, while a vehicle may be designed as a tracked vehicle, the original provided intersection point P may not be suitable or optimal for some specific purpose or for another track system (in case the original track system is replaced).

[0143] As will be described below, when the intersection point P is not well positioned in comparison to a desired performance (e.g. alignment, steering effort, stability, durability etc.), it can be detrimental for the track system 40. Notably, an alignment of the endless track 20 may be impacted, the rolling resistance and / or power consumption may increase, and components may go through more wear.

[0144] The relative position of the intersection point P and the intersection point CoM influence a behavior of the track system 40. Below, different positions of the intersection point P will be described with reference to the center of mass CoM, while thecenter of mass CoM remains generally fixed in place. However, it is contemplated that the center of mass CoM may be moved to obtain the relative position between the intersection point P and the intersection point CoM described below, and have a similar effect on the behaviour of the track system 40. Thus, generally speaking, since the relationship between the position of the center of mass CoM and the position of the intersection point P impact the performance of a steerable track system 40, moving one relative to the other will lead to a similar effect.

[0145] As shown on Figure 3K, the intersection point P can be located at different positions relative to the intersection point CoM. These positions are labelled as position “CENTER”, position “A”, position “B”, position “C”, position “D”, position “E” and position “F”.

[0146] The location of the intersection point P can be described using the quadrants QI, Q2, Q3 and Q4, laterally inward and outward sides IN and OUT, forward and rear sides FRONT and REAR, the longitudinal center plane L, the transversal center plane, the center of mass CoM and / or a transversal plane T’ parallel to the transversal center plane and extending through the center of mass CoM as reference.

[0147] An other way to describe the position of the intersection point P is with reference its longitudinal distance from the center of mass CoM, which may be referred to as a trail distance, and labelled TRAIL in the accompanying Figures, and its lateral distance from the center of mass CoM, which may be referred to as a scrub distance, and labelled SCRUB in the accompanying Figures. The trail distance can be said to be negative when the intersection point P is behind the center of mass CoM, and can be said to be positive when the intersection point P is forward from the center of mass CoM.

[0148] The scrub distance can be said to be positive when the intersection point P is laterally inward from the intersection point CoM (i.e., intersection point P is disposed between the chassis 62 and the intersection point CoM), and can be said to be negative when the intersection point P is laterally outward from the longitudinal center plane L (i.e., intersection point CoM is disposed between the chassis 62 and the intersection point P).

[0149] Referring back to Figure 3K, position A can be said to have a negative trail distance and a neutral scrub distance. Position B can be said to have a negative trail distance and a negative scrub distance. Position C can be said to have a negative trail distance and a positive scrub distance. Position D can be said to have a positive trail distance and a neutral scrub distance. Position E can be said to have a positive trail distance and a negative scrub distance. Position F can be said to have positive trail distance and a positive scrub distance.

[0150] A description of the intersection point P being in its different positions relative to the intersection point CoM, and the related impact on the track system 40 will be provided.Trail Distance

[0151] Many wheeled vehicles have a positive trail distance, as it can assist in straightening the wheels when the vehicle is moving forward. This can enhance stability of the steering assembly 200 in that direction, especially at high velocity. Generally speaking, forces that cause the wheel to follow the steering axis are proportional to the distance between the steering axis and the center of mass. A negative trail on a wheeled vehicle may cause instability because the steering wheels would be induced to turn 180° about the steering axis.

[0152] As shown in Figure 9A, in the presence of a negative trail, a force pushing the wheel to turn can be helpful when applied with to track systems. Track systems are quite different from wheels notably because of their size (height, width) and their larger contact area with the ground. The increased size of the contact area of track systems provides resistance against rotational movement about the steering axis. This resistance may be deemed to be undesirable because it can make the track systems harder to steer. However, stability of the track systems is increased. Indeed, with a negative trail, the frictional force opposes the biases causing the track system to turn 180° about the steering axis, such that steering effort is brought to an acceptable level. Thus, the tendency of the track system to turn by 180° about the steering axis is damped by the increased friction resulting from the increased contact patch. Thus, a negative trail can provide a reducedsteering effect without causing instability. This will be discussed in greater detail below while describing position A, position B and position C.

[0153] As shown in Figures lOA and 10B, a positive trail may be more stable when vehicles are moving in a straight line at high speeds. This will be discussed in greater detail below while describing position D, position E and position F.Scrub Distance

[0154] Many wheeled vehicles have a neutral scrub, because negative and positive scrub distances can cause premature wear and / or increase rolling resistance.

[0155] As shown in Figure 9C, having a positive scrub distance is typical when a vehicle that is originally provided with wheels is converted into a tracked vehicle (i.e., original wheels are replaced with track systems). Typically, this is more a consequence caused by the conversion from wheel to track system rather than a wished configuration by design. As seen in Figure 10A, the original wheeled vehicle has a negative scrub distance.

[0156] As shown in Figures 10A and 10B, having smaller scrub distances (i.e., close to a neutral scrub distance) generally preferable as it can make track systems easier to steer by reducing the amount of friction between the track systems and the ground.General Considerations

[0157] Reffering to Figure 5E, the steering torque S may be decomposed in components Sx, Sy and Sz, with Sz being the main component. The decomposed components can vary according to an orientation of the steering axis 102. It is understood that depending on the orientation of the steering axis (simple or compound angle relative to the vertical direction), the component Sz can have a significative effect on the track system 40 and other components (Sx and / or Sy) may be more or less material and have a more or less significative effect on the track system 40. For instance, but without being bounded to any theory, the component Sz may make the track system 40 to apply more or less pressure toward the longitudinally forward or rearward ends, which can affect the position of the center of mass CoM, as described in U.S. Patent Application No.20130181431, the entirety of which is incorporated by reference herein. For the sake of brevity, in the accompanying Figures, the steering axis 102 is considered to be laterally inclined with respect to a vertical plane.

[0158] In some cases, dl and d2 can be substantially similar. In some other cases, dl and d2 can differ, depending on the loose in the inward / outward directions and if the track system is powered or unpowered. As mentioned previously, the loose can rotate the track system 40 inwardly or outwardly (wl, w2, respectively), where this deviation is added to or substracted from the offset dl / d2 depending on if the track system is powered or unpowered.

[0159] When the track system 40 is steered up to a certain degree where additional torque Mz is inversed (Mz’) when the center of mass (CoM) moves past the point of intersection (P), the direction of the offset (dl) is inverted. This can switch can amplify or reduce the loose in the inward / outward direction (wl, w2, respectively) in some cases.POSITION CENTERForward Direction

[0160] Referring to Figure 4A, the intersection point P is generally longitudinally aligned with the intersection point CoM when the vehicle 60 is travelling in the forward direction, such that the trail distance is neutral (i.e., not positive and not negative).

[0161] Referring to Figures 4B and 4C, the intersection point P is generally laterally aligned with intersection point CoM when the vehicle 60 is travelling in the forward direction. In other words, the scrub distance is neutral (i.e., not positive and not negative).

[0162] Thus, when the intersection point P is in the position CENTER, the intersection point P and the intersection point CoM are aligned with one another.Left Turn

[0163] Referring to Figures 4D and 4E, with the intersection point P being in the position CENTER, when the vehicle 60 is turning in the left direction 80 (i.e., when the track system 40 is steered left), the intersection point P is laterally aligned with the intersection point CoM. Thus, the scrub distance is neutral. Besides from the steering torque S, which is applied by the steering assembly 200, there is no significant torque that is induced with this relative position of the intersection point P and the intersection point CoM.

[0164] It is understood that the same applies when the vehicle 40 turns right, but in a symmetrically opposite direction. Therefore, the track system 40 being steered to the right will not be described herewith.POSITION AForward Direction

[0165] Referring to Figure 5 A, when the vehicle 60 is travelling in the forward direction 80, the intersection point P is longitudinally rearward from the intersection point CoM. Thus, the trail distance is negative.

[0166] Referring to Figures 5B and 5C, when the vehicle 60 is travelling in the forward direction 80, the intersection point P is generally laterally aligned with intersection point CoM. Thus, the scrub distance is neutral.Left Turn - Unpowered Track System

[0167] Referring to Figures 5D and 5E, when the vehicle 60 is turning in the left direction 80, (i.e., the track system 40 is steered left about the steering axis 102) the intersection point P is laterally offset (dl / d2) from the intersection point CoM. Thus, the scrub distance is negative.

[0168] Besides from the steering torque S, an additional torque Mz is induced due to the relative position of the intersection point P and the intersection point CoM by the force F. The force F is directed backward since the track system 40 is unpowered. Moreover, since the offset dl / d2 of the intersection point P is in the opposite directionrelative to the turning direction, the direction of the additional torque Mz is in the same orientation of the steering torque S. Therefore, steering of the track system 40 is facilitated, because the additional torque Mz and the steering torque S collaborate together.

[0169] It is understood that the track system 40 behaves similarly when it turns to the right. The track system 40 undergoing a right turn will therefore not be described in detail herewith.

[0170] This relative positioning of the intersection point P and the intersection point CoM can minimize steering effort, and therefore increase the manoeuvrability of the unpowered track system 40. In some instances, this relative positioning can also cause the instability when travelling forward or backward without any stabilizing means such as antirotation assemblies or steering stabilizer assemblies. Without being bound to any theory, this can be due to the additional torque Mz that does not contribute to bringing the track system 40 back straight when the turning operation is completed, as the additional torque Mz is oriented in the same direction as the steering torque S.

[0171] In some instances, the lateral force FRICTION can be greater than the torque Mz generated by the force F, thereby mitigating the above-described advantages and disadvantages Mz.Left turn - powered track system

[0172] In a similar fashion to Figures 5D and 5E, in this case, when the vehicle 60 is turning in the left direction 80 (i.e., the track system 40 is steered left) the intersection point P is laterally offset (dl / d2) from the intersection point CoM. Thus, the scrub distance is negative. Besides from the steering torque S, an additional torque Mz is induced due to the relative position of the intersection point P and the intersection point CoM by the force F. The force F, however, is directed forward since the track system 40 is powered. Moreover, since the offset dl / d2 of the intersection point P is on the opposite direction relative to the turning direction, the direction of the additional torque Mz is in the opposite orientation of the steering torque S. Therefore, steering of the track system 40 is made more difficult, because the additional torque Mz and the steering torque S are opposite andcompete against each other (i.e., in order to steer the track system 40, the additional torque Mz has to be overcome).

[0173] It is understood that the track system 40 behaves similarly when it turns to the right, thus the track system undergoing the right turn will not be described in detail herewith.

[0174] This case is believed to increase steering effort, thereby decreasing the maneuverability of the powered track system 40. It is also believed that the powered track system 40 may be unstable during steering operations, at least without any stabilizing means, because the additional torque Mz competes against the steering torque S. On the other hand, the additional torque Mz contributes to bring the track system 40 back straight when the steering operation is completed, because the additional torque Mz is oriented opposite to the steering torque S and tends to be null once the track system 40 is going straight.

[0175] It is understood that, in some cases, the lateral force FRICTION can be greater than at least the torque Mz generated by the force F and can mitigate the above- mentioned advantages and disadvantages.POSITION BForward Direction - Unpowered Track System

[0176] Referring to Figure 5 A, in this case, when the vehicle 60 is travelling forwardly (direction 80), the intersection point P is longitudinally rearward from the center of mass CoM on the ground. Thus, the trail distance is negative.

[0177] Referring to Figures 6A and 6B, in this case, when the vehicle 60 is travelling forward, the intersection point P is laterally offset (dl / d2) from the intersection point CoM. Thus, the scrub distance is negative. In this case, the intersection point CoM and the intersection point P are longitudinally and laterally offset from each other as seen in Figure 6B.

[0178] An additional torque Mz is induced due to the relative position of the intersection point P and the intersection point CoM by the force F. The force F is directed backward since the track system 40 is unpowered. Moreover, since the offset (dl / d2) of the intersection P is outward relative to the intersection point CoM, the direction of the additional torque Mz is clockwise as shown in Figure 6B. Therefore, operation of the track system 40 in a straight direction is difficult because the additional torque Mz urges the track system 40 to rotates inwardly (toe-in).Left Turn - Unpowered Track System

[0179] Referring to Figures 6C and 6D, in this case, when the vehicle 60 is turning in the left direction, the point of intersection of the steering axis on the ground (P) is laterally offset (dl / d2) with the projection of the center of mass (CoM) on the ground. Thus, the scrub distance is negative.

[0180] Besides from the steering torque S, an additional torque Mz is induced due to the relative position of the intersection point P and the intersection point CoM by the force F. The force F is directed backward since the track system 40 is unpowered. Moreover, up to a given point, since the offset (dl / d2) of the intersection point P is in the same direction relative to the turning direction, the direction of the additional torque Mz is in the opposite orientation of the steering torque S. Thus, steering of the track system 40 is therefore difficult, because the additional torque Mz and the steering torque S are opposite and competing against each other (i.e., in order to steer the track system 40, the additional torque Mz has to be overcome). Beyond the given point, the direction of the additional torque Mz changes, such that steering becomes easier due to the additional torque Mz and the steering torque S collaborating together.Right Turn - Unpowered Track System

[0181] The opposite phenomenon occurs on a right turn.

[0182] Referring to Figures 6E and 6F, when the vehicle 60 is turning in the right direction, the intersection point P is still laterally offset (dl / d2) with the intersection point CoM such that an additional torque Mz is induced due to the relative position of theintersection point P and the intersection point CoM by the force F. The force F is directed backward since the track system 40 is unpowered. However, since the offset (dl / d2) of the intersection point P is in the same direction relative to the turning direction, the direction of the additional torque Mz is in the same orientation of the steering torque S. Therefore, steering of the track system 40 is facilitated since the additional torque Mz and the steering torque S collaborate when turning right.

[0183] This case can minimize steering effort while increasing the manoeuvrability of the unpowered track system 40 when the track system 40 is steered right, but steering effort is increased and manoeuvrability is decreased when the track system 40 is steered left. Additionally, the track system 40 may be unstable, especially when turning right, at least without any stabilizing means since the additional torque Mz does not contribute to bringing the track system 40 back straight after the turning operation has finished, because it is oriented in the same direction as the steering torque S. For alignment purposes, the deviation is stable and known, so the alignment of the endless track can be easily set in accordance in advance.

[0184] It is understood that, in some cases, the lateral force FRICTION can be greater than at least the torque Mz generated by the force F and can mitigate the above- mentioned advantages and disadvantages.

[0185] This case is believed to minimize steering effort and increase manoeuvrability of the track system 40. In some instances, the track system 40 may be unstable (e.g., inward / outward oscillations or wiggling), at least without any stabilizing means involved.Forward Direction - Powered Track System

[0186] Referring to Figure 5 A, in this case, when the vehicle 60 is travelling forwardly (direction 80), the intersection point P is longitudinally rearward from the center of mass CoM on the ground. Thus, the trail distance is negative.

[0187] In a similar fashion to what is shown in Figures 6A and 6B, in this case, when the vehicle 60 is travelling forwardly, the intersection point P is laterally offset(dl / d2) from the intersection point CoM. Thus, the scrub distance is negative. In this case, the intersection point CoM and the intersection point P longitudinally and laterally offset from each other.

[0188] An additional torque Mz is induced due to the relative position of the intersection point P and the intersection point CoM by the force F. The force F is directed forward since the track system 40 is powered. Moreover, since the offset (dl / d2 of the point of intersection (P) is outward relative to the pt of intersection, the direction of the additional torque (Mz) is counter-clockwise. Operation of the track system 40 in a straight direction may be difficult, because the additional torque Mz urges the track system 40 to rotate outwardly (toe-out).Left Turn - Powered Track System

[0189] In a similar fashion to what is shown in Figures 6C and 6D, in this case, when the vehicle 60 is turning in the left direction, the point of intersection of the steering axis on the ground (P) is laterally offset (dl / d2) with the projection of the center of mass (CoM) on the ground. Thus, the scrub distance is negative. Besides from the steering torque S, an additional torque Mz is induced due to the relative position of the intersection point P and the intersection point CoM by the force F. The force F is directed forward since the track system 40 is powered. Moreover, up to a given point, since the offset (dl / d2 of the point of intersection P is in the same direction relative to the turning direction, the direction of the additional torque Mz is in the same orientation of the steering torque S. Thus, steering of the track system 40 is therefore facilitated since the additional torque Mz and the steering torque S collaborate together. Beyond the given point, the direction of the additional torque Mz changes, such that steering becomes harder due to the additional torque Mz and the steering torque S opposing one another.Right Turn - Powered Track System

[0190] The opposite generally occurs on a right turn.

[0191] In a fashion similar to what is shown in Figures 6E and 6F, when the vehicle 60 is turning in the right direction, the intersection point P is still laterally offset (dl / d2)from the intersection point CoM and an additional torque Mz is induced due to the relative position of the intersection point P and the intersection point CoM by the force F. The force F is directed forward since the track system 40 is powered. However, since the offset (dl / d2 of the intersection point P is in the opposite direction to the turning direction, the direction of the additional torque Mz is in the opposite orientation of the steering torque S. Therefore, steering of the track system 40 is difficult since the additional torque Mz and the steering torque S compete against each other.

[0192] This case can minimize steering efforts while increasing maneuverability of the powered track system 40 when the track system is steered left, but steering effort is increased and maneuverability is decreased when the track system 40 is steered right. Additionally, the track system 40 may be unstable especially when turning left, at least without any stabilizing means since the additional torque Mz does not contribute to bring the track system 40 back straight after the turning operation is finished, because it is oriented in the same direction as the steering torque S.

[0193] It is understood that, in some cases, the lateral force FRICTION can be greater than at least the torque Mz generated by the force F and can mitigate the above- mentioned advantages and disadvantages.POSITION C

[0194] In this case, the behavior of the track system 40 while travelling in the forward or backward direction, while turning left and while turning right, when powered or unpowered, is generally similar to the behavior described in Position B, but symmetrically inversed with respect to the longitudinal center plane L. For the sake of brevity, no repetitive information will be provided.POSITION DForward Direction

[0195] Referring to Figure 7A, in this case, when the vehicle 60 is travelling in the forward direction 80, the intersection point P is longitudinally forward from the intersection point CoM. Thus, the trail distance is positive.

[0196] Referring to Figures 7B and 7C, in this case, when the vehicle 60 is travelling in the forward direction 80, the intersection point P is generally laterally aligned with the intersection point CoM. Thus, the scrub distance is neutral.Left Turn - Unpowered Track System

[0197] Referring to Figures 7D and 7E, in this case, when the vehicle 60 is turning in the left direction 80, the intersection point P is laterally offset (dl / d2) from the intersection point CoM. Thus, the scrub distance is negative. Besides from the steering torque S, an additional torque Mz is induced due to the relative position of the intersection point P and the intersection point CoM by the force F. The force F is directed backward since the track system 40 is unpowered. Moreover, since the offset (dl / d2 of the intersection point P is in the opposite direction relative to the turning direction, the direction of the additional torque Mz is in the opposite orientation of the steering torque S. Steering of the track system 40 is therefore difficult, because the additional torque Mz and the steering torque S are competing against each other (i.e., in order to steer the track system 40, the additional torque Mz has to be overcome).

[0198] It is understood that the track system 40 behaves similarly when it turns to the right, thus the track system undergoing the right turn will not be described in detail herewith.

[0199] This case can increase steering effort and reduce manoeuvrability of the unpowered track system 40. Also, in some cases, the unpowered track system 40 may be stable especially while travelling forward or backward, since the additional torque (Mz) contributes to bring back the track system 40 straight when the turning operation is complete because it is oriented in the opposite direction of the steering torque (S). In some cases, increasing steering effort and / or reducing maneuverability may not be a big deal for slow vehicle, where alignment may be more important, whereas increasing steering effortand / or reducing maneuverability may be problematic for vehicles such as powersport vehicles.

[0200] In some instances, the lateral force FRICTION can be greater than the torque Mz generated by the force F, thereby mitigating the above-described advantages and disadvantages Mz.Left Turn - Powered Track System

[0201] In a similar fashion to what is shown in Figure 7D and 7E, in this case, when the vehicle 60 is turning in the left direction 80, the intersection point P is laterally offset (dl / d2) from intersection point CoM. Thus, the scrub distance is positive.

[0202] Besides from the steering torque S, an additional torque Mz is induced due to the relative position of the intersection point P and the intersection point CoM generated by the force F. The force F is directed forward since the track system 40 is powered. Moreover, since the offset (dl / d2 of the intersection point P is in the opposite direction relative to the turning direction, the direction of the additional torque Mz is in the same orientation as the steering torque S. Steering of the track system 40 is therefore facilitated, because the additional torque Mz and the steering torque S collaborate together.

[0203] It is understood that the track system 40 behaves similarly when it turns to the right, thus the track system undergoing the right turn will not be described in detail herewith.

[0204] This case is believed to minimize steering effort and increase the maneuverability of the track system 40 since the additional torque Mz collaborates with the steering torque S. On the other hand, the additional torque Mz does not contribute to bringing the track system 40 back straight when the turning operation is finished, because the additional torque is oriented in the same direction of the steering torque S. For alignment purposes, the deviation is stable and known, so the alignment of the endless track can be easily set in accordance in advance.

[0205] In some instances, the lateral force FRICTION can be greater than the torque Mz generated by the force F, thereby mitigating the above-described advantages and disadvantages Mz.POSITION EForward Direction - Unpowered Track System

[0206] Referring to Figure 7A, in this case, when the vehicle 60 is travelling in the forward direction 80, the intersection point P is longitudinally forward from the intersection point CoM. Thus, the trail distance is positive.

[0207] Referring to Figures 8A and 8B, in this case, when the vehicle 60 is travelling in the forward direction 80, the intersection point P is laterally offset (dl / d2) from the intersection point CoM. Thus, the scrub distance is positive. Thus, the intersection point CoM and the intersection point P are longitudinally and laterally offset from each other, as best seen in Figure 6B.

[0208] An additional torque Mz is induced due to the relative position of the intersection point P and the intersection point CoM by the force F. The force F is directed backward since the track system 40 is unpowered. Moreover, since the offset (dl / d2 of the intersection point P is outward relative to the intersection point CoM, the direction of the additional torque Mz is clockwise. Operation of the track system 40 in a straight direction is therefore difficult, because the additional torque Mz urges the track system 40 to rotate inwardly (toe-in).Left Turn - Unpowered Track System

[0209] Referring to Figures 8C and 8D, in this case, when the vehicle 60 is turning in the left direction 80, the intersection point P is laterally offset (dl / d2) from the intersection point CoM. Thus, the scrub distance is positive. Besides from the steering torque S, an additional torque Mz is induced due to the relative position of the intersection point P and the intersection point CoM by the force F. The force F is directed backward since the track system 40 is unpowered. Moreover, since the offset (dl / d2) of theintersection point P is in the opposite direction relative to the turning direction, the direction of the additional torque Mz is in the opposite orientation of the steering torque S. Steering of the track system 40 is thus difficult since the additional torque Mz and the steering torque S are competing against each other.Right Turn - Unpowered Track System

[0210] The opposite occurs during a right turn. Referring to Figures 8E and 8F, the intersection point P is still laterally offset (dl / d2) from the intersection point CoM and an additional torque Mz is induced due to the relative position of the intersection point P and the intersection point CoM by the force F. The force F is directed backward since the track system 40 is unpowered. However, up to a given point, since the offset (dl / d2) of the intersection point P is in the opposite direction relative to the turning direction, the direction of the additional torque Mz is in the same orientation of the steering torque S. Steering of the track system 40 is therefore facilitated since the additional torque Mz and the steering torque S are collaborating together. Beyond the given point, the direction of the additional torque Mz changes, such that steering becomes harder due to the additional torque Mz and the steering torque S opposing one another together.[0021 1] This case can minimize steering effort and increase the maneuverability of the unpowered track system 40 when the track system 40 is steered left up to the given point but steering effort is increased and maneuverability is decreased when the track system is steered right tp to the given point. Additionally, the track system 40 may be unstable, especially when turning right, at least without any stabilizing means since the additional torque Mz does not contribute to bringing the track system 40 back straight when the turning operation is finished, because it is oriented in the same direction of the steering torque S.

[0212] It is understood that, in some cases, the lateral force FRICTION can be greater than at least the torque Mz generated by the force F and can mitigate the above- mentioned advantages and disadvantages.Forward Direction - Powered Track System

[0213] Referring to Figure 7A, in this case, when the vehicle 60 is travelling in the forward direction 80, the intersection point P is longitudinally forward from the intersection point CoM. Thus, the trail distance is positive.

[0214] In a similar fashion to what is shown in Figures 8A and 8B, in this case, when the vehicle 60 is travelling in the forward direction 80, the intersection point P is laterally offset (dl / d2) from the intersection point CoM. Thus, the scrub distance is positive. The intersection point P and the intersection point CoM are longitudinally and laterally offset from one another. An additional torque Mz is induced due to the relative position of the intersection point P and the intersection point CoM by the force F. The force F is directed forward since the track system 40 is powered. Moreover, since the offset (dl / d2 of the intersection point P is laterally outward relative to the intersection point CoM, the direction of the additional torque Mz is counter-clockwise. Operation of the track system 40 in a straight direction is thus difficult since the additional torque Mz urges the track system 40 to rotate outwardly (toe-out).Left Turn - Powered Track System

[0215] In a similar fashion to what is shown in Figures 8C and 8D, in this case, when the vehicle 60 is turning in the left direction 80, the intersection point P is laterally offset (dl / d2) from the intersection point CoM. Thus, the scrub distance is positive.

[0216] Besides from the steering torque S, an additional torque Mz is induced due to the relative position of the intersection point P and the intersection point CoM by the force F. The force F is directed forward since the track system 40 is powered. Moreover, since the offset (dl / d2) of the intersection point P is in the same direction relative to the turning direction, the direction of the additional torque Mz is in the same orientation of the steering torque S. Therefore, steering of the track system 40 is facilitated, because the additional torque Mz and the steering torque S collaborate together.Right Turn - Powered Track System

[0217] The opposite occurs during a right turn.

[0218] Referring to Figures 8E and 8F, the intersection point P is still laterally offset (dl / d2) from the intersection point CoM and an additional torque Mz is induced due to the relative position of the intersection point P and the intersection point CoM by the force F. The force F is directed forward since the track system 40 is powered. However, up to a given point, since the offset (dl / d2 of the point of intersection (P) is in the opposite direction relative to the turning direction, the direction of the additional torque Mz is in the opposite orientation of the steering torque S. Steering of the track system 40 is therefore more difficult, because the additional torque Mz and the steering torque S compete against each other. Beyond the given point, the direction of the additional torque Mz changes, such that steering becomes easier due to the additional torque Mz and the steering torque S collaborating together.

[0219] This case can minimize steering effort and increase the maneuverability of the powered track system 40 when the track system is steered left up to the given point but the opposite occurs when the track system is steered right up to the given point. It is also believed to be unstable especially when turning left, at least without any other stabilizing means (e.g., anti-rotation assembly, steering stabilizer assembly, etc.) since the additional torque (Mz) does not contribute to bring back the track system 40 straight when the turning operation is complete because it is oriented in the same direction of the steering torque (S).

[0220] It is understood that, in some cases, the lateral force FRICTION can be greater than at least the torque Mz generated by the force F and can mitigate the above- mentioned advantages and disadvantages.POSITION F

[0221] In this case, the behaviour of the track system 40 while travelling in the forward or backward direction, while turning left and while turning right, when powered or unpowered, is generally similar to the behaviour described in Position E, but symmetrically inversed with respect to the longitudinal center plane L. For the sake of brevity, no repetitive information will be provided.Design of the Track System

[0222] The present technology notably includes configuring the relative position between the intersection point P and the intersection point CoM to obtain desired performance characteristics.

[0223] In some embodiments, a given track system may, when connected to the vehicle 60, have the intersection point P and the intersection point CoM be in one of the above-described positions. Then, the track system can be configured to change the relative position between the intersection point P and the intersection point CoM in order to achieve desired results. The configuration of the track system to modulate the relative positioning between the intersection point P and the intersection point CoM can be done via sensors, a controller and actuators. For example, the tensioner assembly can be actuated to move the idler wheel assembly 121 between elevated and lowered position with respect to the ground surface.

[0224] It is contemplated that the relative position between the intersection point P and the intersection point CoM can be changed by changing the frame 10. Indeed, in a situation where the frame 10 has two members that are pivotally connected to one another, the position of the pivotal connection can be adjusted to cause the center of mass to move toward a front end of the track system 40 or a rear end of the track system 40. In some instances, the movement of the center of mass can cause the relative position between the intersection point P and the intersection point CoM to change.

[0225] It is contemplated that the relative position between the intersection point P and the intersection point CoM can be changed by changing a position of at least one of the idler wheel assemblies 121, 12t. Changing the vertical position of the idler wheel assemblies 121, 12t can cause the ground-engaging segment 21 to be vary, which can in turn change the position of the center of mass.

[0226] It is contemplated that the relative position between the intersection point P and the intersection point CoM can be changed by making the track system 40 asymmetrical about the longitudinal center plane L and / or the transversal center plane T. This can be done by adding and / or removing one or more tandem wheel assemblies on one lateral or longitudinal side of the track system 40.

[0227] It is further contemplated that the relative position between the intersection point P and the intersection point CoM can be changed via the steering knuckle 100. Indeed, the steering knuckle 100 may be configured to provide an updated steering axis that is oriented differently from the steering axis 102, where the updated steering axis provides an updated intersection point on the ground surface, as described above. The steering knuckle 100 can adjust the relative position between the intersection point P and the intersection point CoM between any one of the positions described hereabove.Method for Aligning an Endless Track Based on a Given Configuration of a Steering Assembly Connected Thereto

[0228] A method for aligning an endless track based on a given configuration of a steering assembly will now be described.

[0229] The method has a step 1, which includes determining a current position of the intersection point CoM and a current position of the intersection point P of a given track system (powered or not). The method includes defining the relationship between the current position of the intersection point CoM and the current position of the intersection point P in terms of longitudinal distance (“trail”) and lateral distance (“scrub”) and additional torque (Mz) generated thereby, if applicable. In other words, identify which of positions “CENTER”, “A”, “B”, “C”, “D”, “E” or “F” the current track system currently corresponds to.

[0230] The method also has a step 2, which further includes determining or measuring a loose within the steering assembly 200 and / or the track system 40 by analytical and / or by practical analysis. The method also includes defining a current angular deviation (y loose) of the track system due to the loose and the resulting inward / outward rotated positions of the track system due to the loose. It is contemplated that the current angular deviation can evolve over time due to the wear of the steering assembly and / or of some components of the track system 40.

[0231] The method further has a step 3, which includes determining a total current deviation (y total) of the track system, when the track system travels in a straight forwardor backward direction, a left direction and a right direction, caused by the current position of the center of mass (CoM) and by the current position of the intersection point P and the relationship therebetween and the loose within the steering assembly and / or the track system. Note: the total current angular deviation can evolve over time due to the wear of the steering assembly and / or of some components of the track system.

[0232] The method further has a step 4, which includes analyzing the effect of the total current deviation (y total) on a nominal alignment of an endless track of the track system in comparison with a misalignment limit of the endless track (e.g. gaps between certain portions of the endless track and other components of the track system (e g. idler wheel, support wheel, frame member, etc.)) and determine if said effect of the total current deviation (ytotal) is greater than an acceptable pre-determined threshold beyond which an alignment correction of the assembly (vehicle and track system) is required to minimize the detrimental effect of the total current deviation (y total). If this is the case, the method goes to the step 5.

[0233] The method further includes a step 5, which includes determining which alignment correction to the assembly (vehicle and track system) is required to modify the nominal alignment of the endless track by biasing the track system in opposition to the total current deviation (y total) in order to counteract it and reduce the effect of said total current deviation (y total) at or below the acceptable pre-determined threshold associated with the misalignment of the endless track. Different alignment corrections are possible, depending on if the desired outcome aims to reduce or increase the longitudinal distance (“trail”) and / or the lateral distance (“scrub”) between the center of mass (CoM) and the point of intersection (P). Some contemplated alignment corrections will be described herewith.Example: Alignment correction by Conversion of a Negative Trail into a Positive Trail

[0234] One option includes modifying the configuration of the leading and trailing idler wheel assemblies and / or the height of a pivot pin in order to change the orientation of a resultant force R so that the resultant force R extends under the pivot pin. As a result, the resultant force R generates a torque around the pivot pin that causes more pressure beingapplied behind the intersection point P and therefore moving the center of mass CoM longitudinally behind the intersection point P when the track system is operated. In other words, modifying the longitudinal distance of the center of mass CoM by voluntarily creating a higher pressure to the ground behind the intersection point P.

[0235] An other option includes configuring the track system such that more weight is located longitudinally behind the intersection point P, (e.g. by having an asymmetrical shape relative to the transversal center plane T, or by adding more material longitudinally behind the intersection point P, or by removing material (weight relief) longitudinally in front of the intersection point P, for example.

[0236] An other option includes configuring the track system such that it includes a pivot pin providing a pivotal connection between a first portion (e.g. upper frame member) and a second portion (e.g. lower frame member) and that the pivot pin is located longitudinally behind the point of intersection (P).

[0237] An other option includes configuring the track system such that the support wheels are mounted on a tandem assembly pivoting relative to the frame member and that said tandem assembly is laterally located inward / outward the intersection point P so that the center of mass CoM is moved laterally (scrub). The tandem wheel assembly can be mounted laterally asymmetrically relative to the frame member or the support wheels mounted to the tandem assembly can be mounted laterally asymmetrically relative to the tandem assembly.

[0238] An other option includes modifying the steering axis of the steering assembly of the vehicle by directly or indirectly. To modify the steering axis directly, the method can include replacing a component of the steering assembly that provides a structure defining the steering axis (e.g. kingpin assembly) by a new component providing a steering axis that is oriented adequately to meet the requirements. This can also apply to a suspension assembly, if applicable to the vehicle in question.

[0239] To modify the steering axis directly, the method includes configuring the track system in order to have a camber and / or castor angle that is oriented adequately tomeet the requirements identified at Step 2. This configuration takes in account the existing steering axis and modifies it by the addition of an additional corrective camber and / or castor angle. This can also apply to a custom steering knuckle that can replace an existing one from the vehicle or the track system in order to provide a corrected steering axis. Additional information are provided about in Soucy’s U.S. Patent Application No. US20200223480A1, the entirety of which is incorporated by reference herein.

[0240] An other option includes modifying the steering assembly and / or the track system in order to eliminate, reduce, or increase the inward or outward loose.

[0241] An other option includes adding an alignment adjusting device to the track system for biasing the endless track in at least one of the inward and outward directions, wherein the biasing of the endless track can in one of the inward and outward directions can differ in the other one direction.

[0242] Referring back to the method, it further includes applying an alignment correction to the assembly (vehicle and track system).

[0243] The method further includes repeating steps 1 to 4 to validate the alignment correction.

[0244] Similar options can be used in order to correct / convert a Positive Trail into a Negative Trail by changing the direction of the correction (longitudinally “in front of’ instead of longitudinally “behind of’ and vice versa).

[0245] In a similar fashion, correction / conversion of a Positive Scrub into a Negative Scrub or a vice versa, or a Positive / Negative Scrub into a Neutral Scrub can be performed by changing the direction of the correction (laterally inwardly / outwardly instead of longitudinally “in front of’ or “behind of’).Method for Aligning an Endless Track Based on a Given Configuration of a Steering Assembly Connected Thereto

[0246] The method has a step 1, which includes determining a current position of the intersection point CoM and a current position of the intersection point P of a given tracksystem (powered or not). The method includes defining the relationship between the current position of the intersection point CoM and the current position of the intersection point P in terms of longitudinal distance (“trail”) and lateral distance (“scrub”) and additional torque (Mz) generated thereby, if applicable. In other words, identify which of positions “CENTER”, “A”, “B”, “C”, “D”, “E” or “F” the current track system currently corresponds to.

[0247] The method has a step 2, which includes determining or measuring a loose within the steering assembly and / or the track system by analytical and / or practical analysis of the assembly. The method also includes defining a current angular deviation (y loose) of the track system due to the loose and the resulting inward / outward rotated positions (wl, w2) of the track system due to the loose.

[0248] The method further includes a step 3, which includes configuring the track system such that the scrub is greater than the greatest inward / outward loose in order to ensure that a total current deviation (ytotal) of the track system when the track system travels in forward, rearward, turns left or right, caused by the current position of the center of mass (CoM) and by the current position of the point of intersection (P) and the relationship therebetween and the loose within the steering assembly and / or the track system is predictable. In other words, by having a scrub greater than the greatest of the inward / outward loose, it can ensure that the track system will deviate inwardly / outwardly (toe-in / toe-out) by design, so that the alignment of the endless track is facilitated (since predictable and stable).

[0249] The method also includes a step 4, which includes aligning the endless track based on the configuration described at step 3.

[0250] A method for assessing the need for an alignment correction to an endless track of a track system connectable to a steering assembly of a vehicle will also be described. The method includes determining a total current deviation of the track system with the track system travelling in at least one of a forward direction, a backward direction, a left direction and a right direction. The total current deviation is caused by one or more of i) a current position of a center of mass of the track system, ii) a current position of apoint of intersection of a projection of a steering axis of the steering assembly with aground surface; iii) a relative position between the current position of the center of mass, and iv) a loose between at least one of the steering assembly and the track system.

[0251] The method also includes determining an effect of the total current deviation on a nominal alignment of the endless track of the track system.

[0252] The effect of the total current deviation is greater than an acceptable predetermined threshold indicates that an alignment correction to modify the nominal alignment of the endless track is required.

[0253] Modifications and improvements to the above-described embodiments of the present invention may become apparent to those skilled in the art. The foregoing description is intended to be exemplary rather than limiting. The scope of the present invention is therefore intended to be limited solely by the appended claims.

Claims

What is claimed is:

1. A track system for a vehicle comprising a steering assembly defining a steering axis about which the track system is configured to selectively rotate, the track system comprising: a frame; a drive wheel assembly configured to operatively connect to the steering assembly; at least one idler wheel assembly rotationally connected to the frame; at least one support wheel assembly rotationally connected to the frame; and an endless track drivingly engaged to the drive wheel assembly, and engaged to the at least one idler wheel assembly and to the at least one support wheel assembly, the endless track having a ground-engaging segment configured to engage a ground surface; a lateral center plane; and a longitudinal center plane; wherein the at least one support wheel assembly distributes a load borne by the track system over the ground-engaging segment, the load defining a center of mass, a projection of the center of mass defining a first point of intersection on the ground surface, the first point of intersection being located: at a first longitudinal distance from the lateral center plane; and at a first lateral distance from the longitudinal center plane, a projection of the steering axis defining a second point of intersection on the ground surface, the second point of intersection being located: at a second longitudinal distance from the lateral center plane; and at a second lateral distance from the longitudinal center plane,a difference between the first and second longitudinal distances defining a trail distance, and a difference between the first and second lateral distances defining a scrub distance.

2. The track system of claim 1, wherein: the scrub distance is generally zero; and the second point of intersection is longitudinally rearward from the first point of intersection.

3. The track system of claim 1, wherein: the scrub distance is generally zero; and the second point of intersection is longitudinally forward from the first point of intersection.

4. The track system of claim 1, wherein: the second point of intersection is laterally outward from the first point of intersection, and the second point of intersection is longitudinally rearward from the first point of intersection.

5. The track system of claim 1, wherein: the second point of intersection is laterally outward from the first point of intersection, and the second point of intersection is longitudinally forward from the first point of intersection.

6. The track system of claim 1, wherein: the second point of intersection is laterally inward from the first point of intersection, and the first point of intersection is longitudinally rearward from the first point of intersection.

7. The track system of claim 1, wherein: the second point of intersection is laterally inward from the first point of intersection, and the second point of intersection is longitudinally forward from the first point of intersection.

8. The track system of any one of claims 1 to 7, wherein the first point of intersection is aligned with the longitudinal center plane or laterally offset from the longitudinal center plane.

9. The track system of any one of claims 1 to 8, wherein the drive wheel assembly is configured to be operatively connected to a driving shaft of the vehicle.

10. The track system of any one of claims 1 to 9, wherein the at least one idler wheel assembly also distributes the load borne by the track system over the ground-engaging segment.

11. The track system of claim any one of claims 1 to 10, wherein the frame includes: a first frame member; anda second frame member connected to the first frame member about a pivot point, the pivot point being longitudinally forward from the lateral center plane causing the first point of intersection to be longitudinally closer to a front end of the ground-engaging segment than to a rear end of the ground-engaging segment.

12. The track system of claim 11, wherein the first point of intersection is: longitudinally forward from the second point of intersection; or longitudinally rearward from the second point of intersection.

13. The track system of any one of claims 1 to 10, wherein the frame includes: a first frame member; and a second frame member connected to the first frame member about a pivot point, the pivot point being longitudinally rearward from the lateral center plane causing the first point of intersection to be longitudinally closer to a rear end of the ground-engaging segment than to a front end of the ground-engaging segment.

14. The track system of claim 13, wherein the first point of intersection is : longitudinally forward from the second point of intersection; or longitudinally rearward from the second point of intersection.

15. The track system of any one of claims 1 to 10, wherein: the at least one idler wheel assembly is disposed at one of a front end of the track system and a rear end of the track system, andthe at least one idler wheel assembly is in a predetermined position from the ground surface causing the first point of intersection to be closer to one of the front end of the track system and the rear end of the track system.

16. The track system of any one of claims 1 to 10, wherein the predetermined position is one of: an elevated position relative to the ground surface, causing the first point of intersection to be closer to the one of the front end and the rear end opposite to the at least one idler wheel assembly; and a lowered positioned relative to the ground surface, causing the first point of intersection to be closer to the one of the front end of the track system and the rear end of the at least one idler wheel assembly.

17. The track system of claim 16, wherein the first point of intersection is: longitudinally forward from the second point of intersection; or longitudinally rearward from the second point of intersection.

18. The track system of any one of claims 1 to 10, wherein the track system is asymmetrical about the lateral center plane thereby causing the first point of intersection to be closer to one longitudinal end of the track system.

19. The track system of claim 18, wherein the first point of intersection is: longitudinally forward from the second point of intersection; or longitudinally rearward from the second point of intersection.

20. The track system of any one of claims 1 to 10, wherein the at least one support wheel assembly includes a tandem wheel assembly disposed on at least one lateral side ofthe track system, thereby causing the first point of intersection to be closer to the one lateral side.

21. The track system of claim 11, wherein the first point of intersection is: laterally outward forward from the second point of intersection; or laterally inward from the second point of intersection.

22. The track system of any one of claims 1 to 21, wherein: the steering axis is a first steering axis; the track system further includes a steering knuckle configured to be operatively connected to the steering assembly, the steering knuckle providing a second steering axis, a projection of the second steering axis defining a third point of intersection on the ground surface, the third point of intersection being spaced from the second point of intersection, and the third point of intersection being located: at a third longitudinal distance from the lateral center plane; and at a third lateral distance from the longitudinal center plane.

23. The track system of claim 22, wherein: a difference between the first and third longitudinal distances defines a second trail distance, a difference between the first and third lateral distances defines a second scrub distance, and wherein at least one of: the second trail distance is different from the first trail distance; and the second scrub distance is different from the first scrub distance.

24. The track system of claim 22 or 23, wherein the steering knuckle is configured to replace at least one component of the steering assembly of the vehicle.

25. A vehicle comprising: a frame; a steering assembly supported by the frame; a track system according to any one of claims 1 to 24, the track system being operatively connected to the steering assembly.

26. The vehicle of claim 25, wherein: the steering assembly defines the first steering axis; and the track system further includes a steering knuckle configured to define a second steering axis, the second steering axis being oriented differently from the first steering axis.

27. A track system steerable about a steering axis, the track system comprising: a frame; a plurality of wheel assemblies rotationally connected to the frame; an endless track surrounding the frame assembly and the plurality of wheel assemblies, the endless track having a ground-engaging segment configured to engage a ground surface; a lateral center plane; and a longitudinal center plane; wherein: a load borne by the track system is distributed over the ground-engaging segment, the load defining a center of mass, a projection of the center of massdefining a first point of intersection on the ground surface, the first point of intersection being located: at a first longitudinal distance from a lateral center plane of the track system; and at a first lateral distance from a longitudinal center plane of the track system, a projection of the steering axis defining a second point of intersection on the ground surface, the second point of intersection of the projection of the steering axis being located: at a second longitudinal distance from the lateral center plane; and at a second lateral distance from the longitudinal center plane, a difference between the first and second longitudinal distances defining a trail distance, and a difference between the first and second lateral distances defining a scrub distance.

28. The track system of claim 27, wherein: the scrub distance is generally zero; and the second point of intersection is longitudinally rearward from the first point of intersection.

29. The track system of claim 27, wherein: the scrub distance is generally zero; and the second point of intersection is longitudinally forward from the first point of intersection.

30. The track system of claim 27, wherein: the second point of intersection is laterally outward from the first point of intersection, and the second point of intersection is longitudinally rearward from the first point of intersection.

31. The track system of claim 27, wherein: the second point of intersection is laterally outward from the first point of intersection, and the second point of intersection is longitudinally forward from the first point of intersection.

32. The track system of claim 1, wherein: the second point of intersection is laterally inward from the first point of intersection, and the first point of intersection is longitudinally rearward from the first point of intersection.

33. The track system of claim 27, wherein: the second point of intersection is laterally inward from the first point of intersection, and the second point of intersection is longitudinally forward from the first point of intersection.

34. The track system of any one of claims 27 to 33, wherein the first point of intersection is aligned with the longitudinal center plane or laterally offset from the longitudinal center plane.

35. The track system of any one of claims 27 to 34, wherein the drive wheel assembly is configured to be operatively connected to a driving shaft of the vehicle.

36. The track system of any one of claims 27 to 35, wherein the at least one idler wheel assembly also distributes the load borne by the track system over the groundengaging segment.

37. The track system of claim any one of claims 27 to 36, wherein the frame includes: a first frame member; and a second frame member connected to the first frame member about a pivot point, the pivot point being longitudinally forward from the lateral center plane causing the first point of intersection to be longitudinally closer to a front end of the ground-engaging segment than to a rear end of the ground-engaging segment.

38. The track system of claim 37, wherein the first point of intersection is: longitudinally forward from the second point of intersection; or longitudinally rearward from the second point of intersection.

39. The track system of any one of claims 27 to 36, wherein the frame includes: a first frame member; and a second frame member connected to the first frame member about a pivot point,the pivot point being longitudinally rearward from the lateral center plane causing the first point of intersection to be longitudinally closer to a rear end of the ground-engaging segment than to a front end of the ground-engaging segment.

40. The track system of claim 39, wherein the first point of intersection is : longitudinally forward from the second point of intersection; or longitudinally rearward from the second point of intersection.

41. The track system of any one of claims 27 to 36, wherein: the at least one idler wheel assembly is disposed at one of a front end of the track system and a rear end of the track system, and the at least one idler wheel assembly is in a predetermined position from the ground surface causing the first point of intersection to be closer to one of the front end of the track system and the rear end of the track system.

42. The track system of any one of claims 27 to 36, wherein the predetermined position is one of: an elevated position relative to the ground surface, causing the first point of intersection to be closer to the one of the front end and the rear end opposite to the at least one idler wheel assembly; and a lowered positioned relative to the ground surface, causing the first point of intersection to be closer to the one of the front end of the track system and the rear end of the at least one idler wheel assembly.

43. The track system of claim 42, wherein the first point of intersection is: longitudinally forward from the second point of intersection; or longitudinally rearward from the second point of intersection.

44. The track system of any one of claims 27 to 36, wherein the track system is asymmetrical about the lateral center plane thereby causing the first point of intersection to be closer to one longitudinal end of the track system.

45. The track system of claim 44, wherein the first point of intersection is: longitudinally forward from the second point of intersection; or longitudinally rearward from the second point of intersection.

46. The track system of any one of claims 27 to 36, wherein the at least one support wheel assembly includes a tandem wheel assembly disposed on at least one lateral side of the track system, thereby causing the first point of intersection to be closer to the one lateral side.

47. The track system of claim 46, wherein the first point of intersection is: laterally outward forward from the second point of intersection; or laterally inward from the second point of intersection.

48. The track system of any one of claims 27 to 47, wherein: the steering axis is a first steering axis; the track system further includes a steering knuckle configured to be operatively connected to the steering assembly, the steering knuckle providing a second steering axis, a projection of the second steering axis defining a third point of intersection on the ground surface, the third point of intersection being spaced from the second point of intersection, and the third point of intersection being located: at a third longitudinal distance from the lateral center plane; andat a third lateral distance from the longitudinal center plane.

49. The track system of claim 48, wherein: a difference between the first and third longitudinal distances defines a second trail distance, a difference between the first and third lateral distances defines a second scrub distance, and wherein at least one of: the second trail distance is different from the first trail distance; and the second scrub distance is different from the first scrub distance.

50. The track system of claim 48 or 49, wherein the steering knuckle is configured to replace at least one component of the steering assembly of the vehicle.

51. A vehicle comprising: a frame; a steering assembly supported by the frame; a track system according to any one of claims 27 to 50, the track system being operatively connected to the steering assembly.

52. The vehicle of claim 51, wherein: the steering assembly defines the first steering axis; and the track system further includes a steering knuckle configured to define a second steering axis, the second steering axis being oriented differently from the first steering axis.

53. A steering assembly for a track system defining a center of mass, a projection of the center of mass defining a first point of intersection on the ground surface, the steering assembly comprising: a steering knuckle configured to operatively connect to a track system, the steering knuckle defining a steering axis, a projection of the steering axis defining a second point of intersection on the ground surface, wherein: the second point of intersection is one of: longitudinally forward from the first point of intersection; and longitudinally rearward from the first point of intersection; and the second point of intersection is one of: laterally inward from first point of intersection; and laterally outward from first point of intersection.

54. The track system of claim 53, wherein: the scrub distance is generally zero; and the second point of intersection is longitudinally rearward from the first point of intersection.

55. A method for assessing the need for an alignment correction to an endless track of a track system connectable to a steering assembly of a vehicle, the method comprising: a) determining a total current deviation of the track system with the track system travelling in at least one of a forward direction, a backward direction, a left direction and a right direction, the total current deviation being caused by one or more of: i) a current position of a center of mass of the track system, ii) a current position of a point of intersection of a projection of a steering axis of the steering assembly with a groundsurface; iii) a relative position between the current position of the center of mass, and iv) a loose between at least one of the steering assembly and the track system; and b) determining an effect of the total current deviation on a nominal alignment of the endless track of the track system; wherein the effect of the total current deviation being greater than an acceptable predetermined threshold indicates that an alignment correction to modify the nominal alignment of the endless track is required.

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