Tracked forwarder

Abstract

To provide a tracked vehicle with stability even when handling heavy loads over mountainous terrain.SOLUTION: A tracked vehicle comprises a body extending in a longitudinal direction of the tracked vehicle. The body comprises a front overhang portion (72) and a rear overhang portion (74). A first plane (97) is defined by the area of contact of a track on the ground. An entirety of the front overhang portion (72) is above a second plane (99) passing through a frontmost point of the bottom run of the track and defining an angle between 15° and 30° with the first plane (97); and an entirety of the rear overhang portion (74) is above a third plane passing through a rearmost point of the bottom run of the track and defining an angle between 15° and 35° with the first plane (97). This configuration provides the tracked vehicle with stability even when handling heavy loads over mountainous terrain.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present disclosure relates generally to forwarders, and more specifically, to tracked forwarders operating in mountainous terrain. [Background technology]

[0002] A forwarder is a forestry vehicle that transports felled logs from the stump to a roadside dump. Unlike a skidder, a forwarder transports the logs from the ground, reducing the impact on the soil. Such impact is further reduced by the use of tracks instead of wheels, which is especially important when carrying heavier loads.

[0003] However, larger payloads mean a higher risk of the forwarder tipping over, especially when the forwarder is climbing steep slopes in mountainous areas. This makes it a challenge to design a high-capacity forwarder that is agile and operates safely. Summary of the Invention [Means for solving the problem]

[0004] In accordance with various aspects, the present disclosure relates to a tracked vehicle comprising a car body extending longitudinally of the tracked vehicle, the car body having forward and rear ends defining a length of the car body, the tracked vehicle comprising first and second track systems mounted on respective sides of the car body, each track system having forward and rear ends defining a length of the track system.

[0005] Each track system comprises a track comprising a track having a ground-engaging outer surface and an inner surface opposite the ground-engaging outer surface, the track comprising a top rung and a bottom rung, the ground-engaging outer surface of the bottom rung defining a contact area configured to engage the ground in use, and a track-engaging assembly configured to drive and guide the track about the track-engaging assembly, the track-engaging assembly comprising a plurality of track-contacting wheels and a frame supporting each of the track-contacting wheels.

[0006] The tracked vehicle also includes an operator cabin mounted to the body and including an operator interface for allowing an operator of the tracked vehicle to input operator commands for operating the tracked vehicle. The tracked vehicle includes a powertrain mounted to a portion of the body and including a prime mover.

[0007] Tracked vehicles are configured to enhance payload capacity and / or facilitate operation of the tracked vehicle by an operator from an operator cabin. This can be accomplished in a variety of ways depending on the vehicle body design.

[0008] For example, according to a first broad aspect, a vehicle body is designed with a front overhang portion and a rear overhang portion, the ratio of the length of the vehicle to the length of each track system is 1.25 to 1.75, the entire front overhang portion lies on a second plane that passes through a forward-most point of the track bottom track and defines an angle of between 15° and 30° with a first plane defined by the contact area between the track and the flat ground, and the entire rear overhang portion lies on a third plane that passes through a rear-most point of the track bottom track and defines an angle of between 15° and 35° with the first plane.

[0009] As another example, according to another broad aspect, the car body is designed to have a ratio of the length of the car body to the length of the track system of at least 1.25. The center of mass of the tracked vehicle is located in the forward quarter of the length of the tracked vehicle in the longitudinal direction of the tracked vehicle when the tracked vehicle is unloaded.

[0010] As another example, according to another broad aspect, the car body is configured with a front overhang portion having a length of at least 0.7 m. The entire car body lies on a second plane that intersects a point at the front end of the bottom rung of the track and defines an angle of at least 12° with a first plane defined by the bottom rung of the track.

[0011] As another example, according to another broad aspect, a platform is attached to the carbody, the platform having a loading surface for receiving a load. A first plane defined by the bottom track of the track and a second plane intersecting a front end of the carbody and a front end of the bottom track of the track define an angle of attack of at least 12° for the tracked vehicle. The platform has a height of at least 8m. 2 is configured to support a load of at least 7200 kg over a surface area of

[0012] As another example, according to another broad aspect, the distance between the operator seat and the outer edge of the track of the first track system in the width direction of the tracked vehicle is designed to be between 0.01 m and 0.60 m.

[0013] Two or more of the above aspects may be combined in the same tracked vehicle.

[0014] These and other aspects of the present disclosure will become apparent to those skilled in the art upon review of the following description of the embodiments in conjunction with the accompanying drawings.

[0015] A detailed description of embodiments is provided below, by way of example only, with reference to the accompanying drawings, in which: [Brief description of the drawings]

[0016] [Figure 1] FIG. 1 is a front perspective view of a tracked vehicle carrying a load, according to a non-limiting embodiment. [Diagram 2] FIG. [Diagram 3] FIG. [Figure 4] FIG. [Diagram 5] FIG. [Figure 6] FIG. 2 is a plan view of the operator's cabin of the tracked vehicle. [Figure 7] FIG. 2 is a schematic plan view of the front of the tracked vehicle. [Figure 8] FIG. 1 is a side elevational view of a track system for a tracked vehicle. [Figure 9] FIG. 9 shows the tracks of the track system of FIG. 8 in more detail. [Figure 10] FIG. 9 shows the tracks of the track system of FIG. 8 in more detail. [Figure 11] FIG. 9 shows the tracks of the track system of FIG. 8 in more detail. [Figure 12] FIG. 13 is an elevation view showing contact between a roller wheel of a track engaging assembly of the track system and the track of the track system, and between the track of the track system and the ground. [Figure 13] FIG. 2 is a partial side view of the front of a vehicle approaching a sloped portion of terrain. [Figure 14] FIG. 2 is a side elevational view of another non-limiting embodiment of a tracked vehicle showing a work implement rotating relative to the vehicle chassis about an axis extending across the width of the tracked vehicle; [Figure 15] FIG. 2 is a top view of a further non-limiting embodiment of a tracked vehicle showing a work implement rotating relative to the vehicle chassis about an axis that extends along the height of the tracked vehicle; [Figure 16] FIG. 2 is a schematic diagram illustrating various geometric constraints satisfied by a tracked vehicle in accordance with a non-limiting exemplary embodiment; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] It is to be expressly understood that the description and drawings are for the purpose of illustrating particular embodiments only and are intended to aid in understanding, and are not intended to be, and should not be, limiting.

[0018] 1 to 5 show an embodiment of a vehicle 10 with two track systems 16 including respective tracks 22 for towing the vehicle 10 over a surface 11 (i.e., ground). In this embodiment, the vehicle 10 is a forwarder that may be used to haul logs. The tracks 22 help distribute the weight of the vehicle over a larger contact area, thus reducing the ground pressure of the vehicle, especially in high impact situations when carrying heavy loads.

[0019] The vehicle 10 comprises a body 12, a powertrain 15, the aforementioned track system 16 (which may collectively be referred to as part of the vehicle's "chassis"), and an operator cabin 20 through which an operator controls the operation of the vehicle 10, including its movement over a surface 11. The surface 11 may include roads, but may also include rough terrain consisting of vegetation, hills, ridges, and valleys. As will be further described below, the vehicle 10 is configured to safely operate and travel over such terrain while providing a significant payload capacity.

[0020] The vehicle body 12 (sometimes referred to as the chassis) is a structural member of the vehicle 10 and extends in a longitudinal direction 95 of the vehicle 10. The chassis 12 has a forward end portion 62 and a rear end portion 64 that together define a length of the chassis 12. More specifically, in this embodiment, the forward end portion 62 comprises a forward-most end point 87 of the chassis 12 and the rear end portion 64 comprises a rear-most end point 89 of the chassis 12. In this embodiment, the length of the chassis 12 is equal to the length L of the vehicle 10. V In some embodiments, the length of the chassis 12 represents a substantial portion of the length L of the vehicle 10. V 80% of the length L of the vehicle 10, the remainder being occupied by the platform 18. V However, in other embodiments, the length of the chassis 12 is equal to the length L of the vehicle 10. V 1, the chassis 12 may be at least 90%, at least 95%, or even entirely, i.e., the chassis 12 itself may be at least 90%, at least 95%, or even entirely, of the length L V , where the forward most end point 87 of the chassis is the forward most end point of the vehicle 10 and the aft most end point 87 of the chassis 12 is the aft most end point of the vehicle 10.

[0021] The chassis 12 includes a bottom surface 77. More specifically, in this example, the bottom surface 77 of the chassis 12 is defined to follow the contour of the chassis 12 and defines a height E of the chassis 12 from the ground along the perimeter of the chassis 12. C Define.

[0022] In this embodiment, the vehicle 10 includes a work implement mounted on a chassis 12. For example, in this embodiment, the work implement is a platform 18 for receiving logs and / or forestry machinery. In other embodiments, the vehicle 10 may include other structures (e.g., bins) and / or other types of work implement.

[0023] In this embodiment, the platform 18 comprises a bottom surface 91 configured to face the ground and a top surface 79 configured to receive and support logs and / or forestry machinery. P , i.e. the distance in the height direction of the vehicle 10 between the surface 79 and the ground when the vehicle 10 is on level ground.

[0024] The platform 18 may be attached to the chassis 12 by any suitable means. In this embodiment, the vehicle 10 includes a pivot 105 that rotatably connects the platform 18 to the chassis 12. More specifically, in this embodiment, the pivot 105 connects the rear end portion 64 of the chassis 12 to the rear end portion of the platform 18, and the pivot 105 defines a pivot axis 107 that is located rearward of the track system 16 in the longitudinal direction of the vehicle 10. A portion of the platform 18 may be configured to engage and rest on the chassis 12 such that the chassis 12 supports the platform 18.

[0025] The platform 18 may be rotatable relative to the chassis 12 about a pivot axis that may extend across the width of the vehicle 10. In this embodiment, the vehicle 10 includes a motor 68 for rotating the platform 18 relative to the chassis 12. The vehicle 10 may include additional components for manipulating the platform 18 (e.g., a suspension system, one or more hydraulic cylinders, a locking mechanism, etc.).

[0026] The vehicle 10 may also include other structural elements for supporting the logs and / or forestry machinery. For example, in this embodiment, the vehicle 10 includes one or more posts 112 attached to the perimeter of the platform 18 and configured to hold the logs and / or forestry machinery in place. For example, in this embodiment, the vehicle 10 may include at least one, at least two, at least three, or more posts 112 attached to each side of the platform 18. In some embodiments, the vehicle 10 may also include one or more walls 114 attached around at least a portion of the perimeter of the platform 18 and configured to hold the logs and / or forestry machinery in place. The posts 112 and walls 114 may be attached "vertically". That is, the posts 112 and walls 114 may extend in the height direction of the vehicle 10. The posts 112 and walls 114 may be attached to the platform 18 in any suitable manner, including fastening, welding, etc. In some embodiments, the posts 112 and walls 114 may be removably attached to the platform 18, while in other embodiments the posts 112 and walls 114 may be permanently attached to the platform. The posts 112 and walls 114 may have any suitable length. For example, in some embodiments, each post or wall may have a length of at least 1 meter, in some embodiments at least 1.5 meters, in some embodiments at least 2 meters, and in some embodiments even longer.

[0027] In the illustrated embodiment, the vehicle 10 includes a protective wall 116 that extends at least partially over the powertrain 15 and / or operator cabin 20 of the vehicle 10 to prevent objects (such as logs carried on the platform 18) from falling on and damaging the powertrain 15 or operator cabin. For example, the protective wall 116 may extend from an upper portion of a forward one of the walls 114. However, the protective wall 116 is not required in all embodiments.

[0028] The platform 18, the supports 112, and the walls 114 may define a volume of the vehicle 10. More specifically, the surface area of ​​the platform 18 may be multiplied by the length of the supports 112 and the walls 114 to define the volume of the vehicle 10. In this embodiment, the vehicle 10 may be configured to have a significant volume relative to the size of the vehicle 10. The volume of the vehicle 10 may be greater than the volume of a comparably sized prior art vehicle. For example, in some embodiments, the volume may be at least 10 m 3 , in some embodiments at least 12 m 3 , in some embodiments at least 14 m 3 , and in some embodiments even more (e.g., at least 16 m 3 To illustrate the relative volume relative to the size of the vehicle 10, in some embodiments, the length L of the track system 16 may be: TS The ratio of volume to volume is at least 2.2m 2 and in some embodiments at least 2.6 m 2 , in some embodiments at least 3 m 2 , and in some embodiments even more (e.g., at least 3.2 m 2 ) may also be used.

[0029] In the illustrated embodiment, the vehicle 10 includes a front overhang portion 72 longitudinally forward of the track system 16 and a rear overhang portion 74 longitudinally rearward of the track system 16. The front overhang portion 72 of the vehicle 10 is longitudinally forward of the frontmost roller wheel 28 of the track system 16. In this embodiment, the front overhang portion 72 of the vehicle 10 may span a portion of the chassis 12, at least a portion of the operator cabin 20, and at least a portion of the powertrain 15. The rear overhang portion 74 of the vehicle 10 is longitudinally rearward of the rearmost roller wheel 28 of the track system 16. In this embodiment, the rear overhang portion 74 of the vehicle 10 may span a portion of the chassis 12 and a portion of the platform 18. Because the vehicle 10 is supported by the track system 16, in this embodiment, the forward portion of the vehicle 10 before the connection between the track system 16 and the chassis 12 is a front overhang portion 72, and the rearward portion of the vehicle 10 behind the connection between the track system 16 and the chassis 12 is a rear overhang portion 74. A majority (in the length direction) of each of the front overhang portion 72 and the rear overhang portion 74 is configured to protrude above the ground when the vehicle 10 is in use and to avoid the track system 16 below.

[0030] In some embodiments, the platform 18 is configured to accept a payload of at least 6000 kg (e.g., 6000 kg to 9000 kg), in other embodiments at least 6600 kg (e.g., 6600 kg to 8000 kg), in further embodiments at least 7200 kg (e.g., about 7200 kg), and in other embodiments even more. The platform 18 may have a suitable geometry to accept such a payload. For example, in some embodiments, the thickness of the platform 18 may be between 0.10 m and 0.30 m, more specifically about 0.20 m. To this end, the platform 18 may also include or be made of any suitable material. For example, in some embodiments, the platform 18 includes a metallic material, such as steel, aluminum, and the like. In some embodiments, depending on the operational requirements, the platform may include a polymeric material, such as a plastic, a composite material, and the like.

[0031] The powertrain 15 is mounted to a portion of the chassis 12 and is configured to generate power and transmit the power to the track system 16 to propel the vehicle 10 on the ground. More specifically, in this embodiment, the powertrain 15 is mounted to the undercarriage 76 of the chassis 12. To that end, the powertrain 15 includes a prime mover 14, which is a power source including one or more motors. For example, in this embodiment, the prime mover 14 includes an internal combustion engine. In other embodiments, the prime mover 14 may include another type of motor (e.g., an electric motor) or a combination of different types of motors (e.g., an internal combustion engine and an electric motor). The prime mover 14 is in a driving relationship with the track system 16. That is, the powertrain 15 transmits power generated by the prime mover 14 to one or more of the track systems 16 to drive (i.e., impart motion to) the one or more track systems 16. The powertrain 15 may transmit power from the prime mover 14 to the track systems 16 in any suitable manner. In this embodiment, powertrain 15 includes a transmission (not shown) between prime mover 14 and a pair of final drive axles 56 (one for each of track systems 16) for transferring power from prime mover 14 to track systems 16. The transmission may be an automatic transmission (e.g., a continuously variable transmission (CVT)) or any other suitable type of transmission.

[0032] In the illustrated embodiment, at least a portion 101 (i.e., a portion, a majority, or all) of the powertrain 15 is mounted adjacent the operator cabin 20 across the width of the vehicle 10. In this embodiment, at least a portion 103 of the powertrain 15 is mounted adjacent the operator cabin 20 across the length of the vehicle 10.

[0033] As shown in FIGS. 6 and 7, the operator cabin 20 is where the operator sits and controls the vehicle 10. More specifically, the operator cabin 20 is attached to a portion of the chassis 12 on a given side of the chassis 12 (e.g., the left side when driving). In this embodiment, at least a portion of the powertrain 15 is attached adjacent to the operator cabin 20 in the width direction of the vehicle 10 on the other side of the vehicle 10 (e.g., the right side). The operator cabin 20 includes a first side window 81 toward the left side of the chassis 12 and a second side window 82 toward the right side of the chassis 12. The operator cabin 20 includes an operator seat 71 facing a user interface 70, which includes a set of controls that allow the operator to input operator commands for operating the vehicle 10 while sitting in the seat 72 (e.g., for steering the vehicle 10 on the ground and operating the work implement, if any). For example, in this embodiment, the user interface 70 includes accelerator, brake controls, and steering device 75 that can be steered by the operator to control the movement of the vehicle 10 on the ground. The user interface 70 also includes an instrument panel (eg, dashboard) that provides indicators (eg, speedometer indicator, tachometer indicator, etc.) to convey information to the operator.

[0034] The track system 16 engages the ground to propel the vehicle 10. In this embodiment, the track system 16 includes a first track system 16 mounted on the right side of the chassis 12 and a second track system 16 mounted on the left side of the chassis 12.

[0035] As shown in FIG. 8, each track system 16 includes a track-engaging assembly 21 and a track 22 disposed about the track-engaging assembly 21. The track 22 engages the ground to provide traction to the vehicle 10. In this embodiment, the track-engaging assembly 21 includes a plurality of track-contacting wheels and a frame 13 that supports various components of the track system 16, including the track-contacting wheels. In this embodiment, the track-contacting wheels include a drive wheel 24 at a first longitudinal end of the track system 16 and a plurality of idler wheels including an idler wheel 26 at a second longitudinal end of the track system 16 opposite the first longitudinal end of the track system 16. More specifically, in this embodiment, the first longitudinal end is a front end portion, the drive wheel 24 is aligned with the powertrain 15 in the longitudinal direction of the vehicle 10, and the second longitudinal end is a rear end portion, with the idler wheel 26 being a rear (rear end) idler wheel. In this embodiment, the track-contacting wheels also include a plurality of roller wheels 28 that support at least a portion (i.e., some, most, or all) of the weight of the vehicle 10, and in some embodiments, one or more support wheels 29 for supporting a portion of the track 22.

[0036] Each track system 16 has a length L of the track system 16 along a longitudinal axis 61 that defines the length of the track system 16. TS 22。 Track system 16 has a width direction and a width defined by the width W of track 22. Track system 16 also has a height direction perpendicular to its length and its width direction.

[0037] The vehicle 10 is steerable by a steering system responsive to user input at the steering device 75 to orient the vehicle 10 about a steering axis 96 of the vehicle 10. Thus, the orientation of each longitudinal axis 61 of the track system 16 is adjustable relative to the longitudinal axis 95 of the vehicle 10. Steering may be achieved by controlling the track systems 16 to move one track faster than the other. Different amounts of tractive force applied to each side of the vehicle 10 controllably changes the orientation of the longitudinal axis 95 of the vehicle 10.

[0038] The track 22 has a suitable length to facilitate easy attachment around the track engagement assembly 21. The track 22 may be referred to as an "endless" track given its closed configuration with no ends that allows it to be positioned and moved around the track engagement assembly 21. With further reference to Figures 9-11, the track 22 includes an inner side 45, a ground engaging outer side 47, and side edges 491, 492. The inner side 45 faces the wheels 24, 26, 28, 29, and the ground engaging outer side 47 engages the ground.

[0039] An upper rung 65 of the track 22 extends above the wheels 24, 26, 28, 29 between the longitudinal ends 57, 59 of the track system 16, while a bottom rung 66 of the track 22 extends below the wheels 24, 26, 28, 29 between the longitudinal ends 57, 59 of the track system 16. The bottom rung 66 of the track 22 defines the contact area between the track 22 and the ground, which generates traction and carries the majority of the load on the track system 16, and may be referred to as the "contact patch" of the track 22 with the ground.

[0040] It should be understood that top rung 65 and bottom rung 66 refer to fixed portions of track 22 when track 22 is not moving. However, when track 22 is moving, top rung 65 and bottom rung 66 are defined at a given moment in time, with top rung 65 being the portion of track 22 that happens to extend between longitudinal ends 57, 59 of track system 16 and that is above wheels 24, 26, 28, 29 at that time, and bottom rung 66 of track 22 being the portion of track 22 that happens to extend between longitudinal ends 57, 59 of track system 16 and that is below wheels 24, 26, 28, 29 at that time.

[0041] The track 22 has a longitudinal axis 19, which includes a width direction of the track 22 (i.e., a lateral direction generally perpendicular to its longitudinal axis) and defines a longitudinal direction of the track 22 (i.e., a direction generally parallel to its longitudinal axis) and a lateral direction of the track 22 (i.e., a direction perpendicular to its longitudinal axis).

[0042] In this embodiment, the track 22 is relatively wide to efficiently distribute the load of the vehicle 10 across the surface of the terrain 11. For example, in some embodiments, the width W of the track 22 is Tは , at least 24 inches, in some cases at least 36 inches, in some cases at least 48 inches, and in some cases even more.

[0043] In some cases, the track 22 may be an elastomeric track, which includes an elastomeric material so that it is flexible around the track engagement assembly 21. The elastomeric material of the track 22 may include any polymeric material having suitable elasticity. In this embodiment, the elastomeric material of the track 22 includes rubber. Various rubber mixtures may be used, and in some cases, different rubber mixtures may be present in different regions of the track 22. In other embodiments, the elastomeric material of the track 22 may include another elastomer (e.g., a polyurethane elastomer) in addition to or instead of rubber. In one embodiment, the track 22 is a metal embedded rubber track (MERT).

[0044] Structurally, the track 22 comprises an endless body 36 underlying its inner side 45 and its ground-engaging outer side 47. Given its underlying nature, the body 36 is referred to as a "carcass." In this embodiment, the carcass 36 comprises a base 90. The carcass 36 and its base 90 are elastomeric in that the base 90 comprises an elastomeric material 38, which allows the carcass 36 to elastically change shape and thus flex as the track 22 moves about the track-engagement assembly 21. In some embodiments, the carcass 36 comprises a plurality of reinforcements, such as spaced apart reinforcements embedded in its elastomeric material 38. These reinforcements can take a variety of forms, such as reinforcing layers. For example, in this embodiment, the base 90 of the carcass 36 may include a layer of reinforcing cable (e.g., a cord including multiple strands (e.g., woven fiber or metal wire), other type of cable, etc., which may be made of any material (e.g., metal, plastic, or composite fiber or wire) that is suitably flexible along the longitudinal axis of the cable) that is adjacent to one another and extends generally longitudinally of the track 22 to increase the tensile strength of the track 22 along its longitudinal direction. As another example, in this embodiment, the base 90 of the carcass 36 may include a layer of reinforcing fabric, typically including a thin, flexible material made by weaving, felting, knitting, interweaving, or otherwise intersecting natural or synthetic elongated fabric elements such as fibers, filaments, strands, and / or the like (e.g., nylon fibers or other synthetic fibers), whereby some of the elongated fabric elements extend transversely to the longitudinal direction of the track 22 to have a reinforcing effect in the transverse direction of the track 22.

[0045] The carcass 36 may be formed into a desired shape in a molding process that cures the rubber 38. For example, in this embodiment, a mold may be used to consolidate layers of rubber to provide the layers of rubber 38, reinforcing cables, and reinforcing fabric of the carcass 36.

[0046] The inner side 45 of the track 22 includes the inner surface 32 of the carcass 36 and a plurality of wheel contacting protrusions 48 protruding from the inner surface 32 and positioned to contact at least some of the wheels 24, 26, 28, 29 to drive (i.e., impart motion to) and / or guide the track 22. The wheel contacting protrusions 48 may also be referred to as "wheel contacting protrusions." Additionally, the wheel contacting protrusions 48 may also be referred to as "drive / guide protrusions" or "drive / guide protrusions" since they are used to at least one of drive the track 22 and guide the track 22. In some embodiments, the drive / guide protrusions 48 may interact with the drive wheels 24 to drive the track 22, in which case the drive / guide protrusions 48 are drive protrusions. In other embodiments, the drive / guide protrusions 48 may not be used to drive the track 22 but may instead interact with the idler wheels 26 and / or roller wheels 28 to guide the track 22 to maintain proper track alignment and prevent run-off, in which case the drive / guide protrusions 48 are guide protrusions. In this embodiment, the drive / guide protrusions 48 may both (i) interact with the drive wheels 24 to drive the track, and (ii) interact with the idler wheels 26 and / or roller wheels 28 to guide the track 22 to maintain proper track alignment and prevent run-off, in which case the drive / guide protrusions 48 are both drive and guide protrusions.

[0047] The ground engaging exterior 47 of the track 22 includes a ground engaging outer surface 31 of the carcass 36 and a tread pattern 40 for enhancing traction on the ground. The tread pattern 40 includes a plurality of traction lugs 58 extending from the ground engaging outer surface 31 and spaced apart along the length of the track 22 for engaging the ground to enhance traction. The traction lugs 58 are sometimes referred to as "tread lugs" or "traction lugs."

[0048] In this embodiment, the base 90 of the carcass 36 includes the inner surface 32 of the carcass 36 and a portion of the ground-engaging outer surface 31 of the carcass 36 .

[0049] The drive wheels 24 are rotatable by power available from the prime mover 14 to drive the track 22. That is, the power generated by the prime mover 14 and transmitted through the powertrain 15 of the vehicle 10 is transmitted to the final drive axle 56. i can be rotated, which rotates the drive wheels 24 and, therefore, imparts motion to the track 22.

[0050] In this embodiment, drive wheel 24 comprises a sprocket having a plurality of drive members (e.g., teeth) spaced along a circular path for engaging drive / guide projections 48 of track 22 to drive track 22. Thus, drive wheel 24 and track 22 provide a "positive drive" configuration.

[0051] The idler wheels 26, roller wheels 28 and support wheels 29 are not driven by power provided by the prime mover 14, but rather are used to at least one of support a portion of the weight of the vehicle 10 on the ground via the track 22, guide the track 22 as it is driven by the drive wheels 24, and provide tension to the track 22. More specifically, in this embodiment, the idler wheels 26 are rear end idler wheels that help maintain tension in the track 22 and support a portion of the weight of the vehicle 10 on the ground via the track 22. With reference to Figures 8 and 10, the roller wheels 28 roll on a rolling path 33 on the inside 45 of the track 22 along a bottom track 66 of the track 22 to bring the bottom track 66 into contact with the ground. In this case, the roller wheels 28 can be referred to as "middle rollers" since they are located between the front and rearmost wheels of the track system 16.

[0052] In this embodiment, the vehicle 10 has a relatively large payload capacity, which is made possible by the platform 18 having a relatively large payload surface area. For example, the platform 18 has a length L between 3m and 5m, in some embodiments between 3.5m and 4.5m, and in some embodiments about 4m. PThe platform may have a width of between 1.5m and 3m, in some embodiments between 2m and 3.5m, and in some embodiments about 2.3m. As a result, platform A L The loading surface area of ​​the 2 15m from 2 and in some embodiments, in the range of 6 m 2 and 12m 2 In some embodiments, about 9.2 m 2 Other dimensions are possible.

[0053] In all cases, the range of lengths L of the platform 18 Pは , the length L of vehicle 10 V The length L of the track system 16 TS This contributes to making the length at least L RO However, it has been found that this can lead to instability unless certain design constraints are taken into account.

[0054] Thus, in certain non-limiting embodiments, it has been found that positioning the operator cabin 20 and power train 15 such that at least a portion (i.e., some, most, or all) of the operator cabin 20 is located (from a longitudinal perspective) forward (longitudinally) of the longitudinal leading end 57 of the track system 16 can aid in stabilizing the vehicle 10. This provides the front overhang portion 72 with a length L to balance potential loads on the platform 18, and particularly the rear overhang portion 74. FO is given.

[0055] Thus, locating the operator cabin 20 at least partially in the front overhang portion 72 can act as a counterweight to balance the vehicle 10 as it climbs a slope and loads the platform 18. This design results in the operator cabin 20 and powertrain 15 being positioned toward the front of the vehicle 10 (so that the majority of the operator cabin 20 overlies the space that overhangs the track system 16) and can result in the center of mass of the vehicle 10 being located in the forward-most quarter (or fifth or sixth) of the length of the vehicle 10 in the longitudinal direction of the vehicle 10 (mass measured when the vehicle 10 is unladen).

[0056] In addition to stability, other constraints may be related to the requirement to traverse hilly terrain, which is the need to challenge gradients from flat to uphill or downhill to flat. In such cases, the "maximum angle of attack" of the vehicle 10 becomes important. The maximum angle of attack (there may be more than one) may be defined by the maximum angle of a slope that the vehicle 10 can overcome while contacting the ground only with the track 22 as it moves in a particular direction. For example, the maximum angle of attack may include a maximum angle of attack in a forward direction, which may be defined by the maximum angle of a slope that the vehicle 10 can overcome while contacting the ground only with the track 22 as it moves forward, and a maximum angle of attack in a rearward direction, which may be defined by the maximum angle of a slope that the vehicle 10 can overcome while contacting the ground only with the track 22 as it moves in a rearward direction.

[0057] The maximum forward angle of attack of the vehicle 10 can be defined as the angle between two planes 97, 99, as shown in Figure 4. The first plane 97 is the plane defined by the contact surface of the bottom rung 66 of the track 22. The second plane 99 is the plane that intersects with the first plane at the forward-most end 111 of the bottom rung of each track 22 (with the vehicle not steering right or left). The maximum intersection angle between the first and second planes that still allows the entire vehicle (particularly the front overhang portion 72) to be positioned above the second plane is the maximum angle of attack.

[0058] One method for determining the maximum angle of attack in the forward direction from the geometric shape of the vehicle 10 will now be described with further reference to Figures 4 and 13. In this embodiment, the chassis 12 may define the bottom of the front overhang portion 72 of the vehicle 10. Specifically, the distance between the bottom surface 77 of the chassis 12 and a first plane 97 (e.g., flat ground) is defined as the height E of the chassis 12. C (x), where the x-axis extends longitudinally of the vehicle 10 toward the rear end portion of the vehicle 10, and x=0 represents the front end portion 62 of the chassis 12. C The value of (x) is x=0 to x=L FO It changes as the height E C (x) generally decreases, but x=0 and x=L FO It can vary between E C Each value of (x) creates a respective angle α(x) with the forward end of the bottom rung of each of the two tracks 22. This forward end of the bottom rung of each of the two tracks 22 is given by x=L FO +L1 occurs. Therefore: α(x)=tan -1 (E C (x) / (L FO +L1-x).

[0059] The minimum value of this angle, i.e., from x=0 to x=L FO min{α(x)} over α A The maximum forward angle of attack is indicated by

[0060] In some embodiments, the geometry of the orbital system 16 may result in a maximum angle of attack α A For example, in some embodiments, (i) between the drive wheel 24 and the first roller wheel 28 (in other words, x=L FO and x=L FO +L1) and (ii) a second segment of the bottom rung 66 of the track 22 between the roller wheels 28, the angle between which is equal to the maximum angle of attack α AIn particular, the track system 16 may be configured to prevent a significant portion of the first segment of the track 22 from engaging the ground and / or supporting the vehicle 10. More specifically, in some embodiments, the geometry of the track system 16 may prevent the drive wheels 24 from supporting a portion of the weight of the vehicle 10 to improve durability and avoid deformation and premature deterioration of the drive wheels 24 and any gears, shafts, or other drive components that engage the drive wheels 24.

[0061] Therefore, the geometry of the chassis 12 is such that the maximum angle of attack α A More specifically, while there may be limited design freedom in choosing L1 (the length of the inclined portion of the track 22), the parameter L FO and E C There is considerable freedom in choosing (x), and a higher maximum angle of attack α A If you are aiming for a design with the same value of E C For (x), L FO On the other hand, in order to increase the load capacity, it is necessary to keep in mind the stability provided by the front overhang portion 72 (to balance the rear overhang portion 74). Therefore, the stability (L FO ) and angle of attack (L FO There is a design tension between the higher values ​​of E C It was found that the solution was (x). This resulted in the maximum angle of attack α A Larger payload (non-zero L) without compromising RO In order to obtain greater stability at FO The value of can be increased.

[0062] As contemplated in this disclosure, higher values ​​of E C (x) can be achieved by providing a raised chassis 12 and / or a raised platform 18. At the front, this is FO Even if the maximum angle of attack αA This has the effect of increasing the vehicle 10's forward or backward travel distance, thereby enabling the vehicle 10 to enter slopes having higher gradients, such as may be encountered at the start of an uphill run or at the bottom of a hill, without increasing the risk of the vehicle tipping forward or backward.

[0063] In a specific, non-limiting example, the forward end 87 of the chassis 12 (i.e., the forward-most portion of the forward overhang portion 72) is spaced apart from the maximum angle of attack α A In other words, if one were to draw a second plane 99 connecting the front end of the chassis to the forward-most end of the bottom rung of each track 22, all of the chassis 12 would be above the second plane 99, and no part of the chassis 12 would intersect with the second plane 99. The angle of intersection of the second plane 99 with the first plane 97 defines a maximum angle of attack α A It is.

[0064] In other words, in certain non-limiting embodiments, the track is positioned at a constant longitudinal distance (i.e., L FO +L1) at the front end of the chassis 12 (i.e., E at x=0 C (x)) is the specific vertical distance (i.e., L FO +L1), and the arctangent is the maximum angle of attack α A The value that gives the value is obtained.

[0065] Therefore, the desired maximum angle of attack α of the vehicle 10 Aは , the vehicle 10 is at least α A This also means that the maximum angle of attack α A To satisfy the above, the height of the chassis 12 at the front end of the chassis 12 at a given longitudinal distance from the forwardmost end point of each bottom run of each track, divided by that particular longitudinal distance, is given by tan(α A ) or less.

[0066] In the foregoing context, it has been discovered how to balance payload requirements (which affect the overall length of the chassis), stability requirements (which affect the ratio of the length of the chassis to the length of the track), and maximum angle of attack requirements (which affect the ratio of the height of the chassis (particularly, in some embodiments, the front end of the chassis) to the (longitudinal) distance between the front end of the chassis and the forward-most point of the bottom rung of the track). The latter ratio, in some embodiments, may be the tangent of the maximum angle of attack.

[0067] With reference to a specific numerical example, in one non-limiting embodiment, the length L of the vehicle 10 V may be about 6.725 m, and the length L of the track system 16 TS Length L of vehicle 10 V may be about 1.50, and the length L of the track system 16 TS Length L of platform 18 P may be about 0.85, the maximum angle of attack of the vehicle 10 may be about 22.5°, and the minimum height E of the chassis 12 at the front overhang 72 of the vehicle 10 may be about 22.5°. C may be the distance between the lowest point of the front overhang portion 72 and the first plane 97, which may define the minimum height of the front overhang portion, which may be at least 0.40 m (e.g., 0.40 m to 0.60 m), and more specifically, may be about 0.45 m; and the height E of the chassis 12 at the front end 87 of the chassis 12 may be the distance between the lowest point of the front overhang portion 72 and the first plane 97, which may define the minimum height of the front overhang portion, which may be at least 0.40 m (e.g., 0.40 m to 0.60 m), and more specifically, may be about 0.45 m. C may be about 0.75 m, and the length L of the front overhang portion 72 FOは It may be about 1 m.

[0068] In another non-limiting embodiment, the length L of the vehicle 10 Vは , at least 5.5 m (e.g., 5.5 m to 8 m), at least 6 m (e.g., 6 m to 7.5 m), or at least 6.5 meters (e.g., 6.5 meters to 7 meters). TS Length L of vehicle 10 VThe ratio of the length L of the track system 16 may be at least 1.25 (e.g., 1.25 to 1.75), or at least 1.35 (e.g., 1.35 to 1.65), or at least 1.45 (e.g., 1.45 to 1.55). TS Length L of platform 18 P The ratio of may be at least 0.65 (e.g., 0.65 to 1.05), or at least 0.75 (e.g., 0.75 to 0.95). The maximum angle of attack of the vehicle 10 may be at least 15° (e.g., 15° to 30°), more specifically at least 17.5° (e.g., 17.5° to 27.5°), and more specifically at least 20° (e.g., 20° to 25°). The minimum height E of the chassis 12 at the front overhang portion 72 of the vehicle 10 may be at least 15° (e.g., 15° to 30°), more specifically at least 17.5° (e.g., 17.5° to 27.5°), and more specifically at least 20° (e.g., 20° to 25°). C The height E of the chassis 12 at the front end 87 of the chassis 12 may be at least 0.3 m (e.g., 0.3 m to 0.6 m), and more specifically, at least 0.4 m (e.g., 0.4 m to 0.5 m). C The length L of the front overhang portion 72 may be at least 0.6 m (e.g., 0.6 m to 0.9 m), and more specifically, at least 0.7 m (e.g., 0.7 m to 0.8 m). FO may be at least 0.7 m (eg, 0.7 m to 1.3 m), more specifically at least 0.8 m (eg, 0.8 m to 1.2 m), and more specifically at least 0.9 m (eg, 0.9 m to 1.1 m).

[0069] While the above discusses the front end of the vehicle 10 and the front overhang portion 72, one skilled in the art will appreciate that similar calculations and similar functionality may be required for the rear end of the vehicle 10 and the rear overhang portion 74 of the vehicle 10. In this embodiment, the rear end of the vehicle 10 is defined by a platform 18. The platform 18 is mounted on the chassis 12 and at some portions of the vehicle 10 is above the chassis height E C (e.g., according to a different profile and having a different value), PThe maximum rearward angle of attack of the vehicle 10 may be defined as the angle between the plane 97 and a second plane that intersects with the first plane 97 at the rearmost end 113 of the bottom track 66 of each track 22 (with the vehicle not steering right or left). The maximum intersection angle between the first and second planes that allows the entire vehicle (particularly the rear overhang portion 74) to be positioned above the second plane is the maximum rearward angle of attack. Similar to the maximum forward angle of attack, one method of determining the maximum rearward angle of attack from the geometry of the vehicle 10 is to multiply the distance between the bottom surface 77 of the chassis 12 and the first plane 97 (e.g., flat ground) by the height E of the chassis 12. C (x), and the distance between the bottom surface 91 of the platform 18 and the first plane 97 (e.g., flat ground) is defined as the height E of the platform 18. P 2. Consider the x-axis as (x), where the x-axis extends longitudinally of the vehicle 10 toward the rear end portion of the vehicle 10, with x=0 being aligned vertically with the rearmost end of the bottom rung 66 of the track 22. In this embodiment, the chassis 12 and platform 18 may define the bottom of a rear overhang portion 74 of the vehicle 10. C (x) and E P The value of (x) is x=0 to x=L RO It changes as the height E C (x) and E P (x) generally increases, but x=0 and x=L RO It can vary between E C (x) and E P Each value of (x) creates a respective angle β(x) with the rearmost end of the bottom rung of each of the two tracks 22. This rearmost end of the bottom rung of each of the two tracks 22 is given by x=L RO +L2 occurs. Therefore: β(x)=min{tan -1 (E C (x) / x);tan -1 (E P (x) / x)}

[0070] The minimum value of this angle, i.e., from x=0 to x=L ROmin{β(x)} over β A β is the maximum angle of attack in the rearward direction, which is the maximum angle of attack when the vehicle 10 is at least β A This also means that the slope of

[0071] At the rear of the vehicle 10, as contemplated in this disclosure, a higher value of E C (x) can be achieved by providing a raised chassis 12 and / or a raised platform 18. This provides the same value of L RO Maximum angle of attack β A It has the effect of increasing

[0072] This maximum angle of attack β A To satisfy the above, the height of the chassis 12 at the rear end of the chassis 12 at a given longitudinal distance from the rearmost point of the bottom rung of each track, divided by that particular longitudinal distance, is given by tan(β A ) or less.

[0073] In the foregoing context, it has been discovered how to balance payload requirements (which affect the overall chassis length and vehicle length), stability requirements (which affect the ratio of chassis length to track length and vehicle length to track length), and maximum angle of attack requirements (which affect the ratio of the height of the chassis and platform (particularly, in some embodiments, the rear end of the chassis and the rear end of the platform) to the (longitudinal) distance between the rear ends of the chassis and platform and the aft-most point of the bottom rung of the track). The latter ratio, in some embodiments, may be the tangent of the maximum angle of attack.

[0074] In some embodiments, the geometry of the orbital system 16 may result in a maximum angle of attack β AFor example, in some embodiments, the angle between (i) a first segment of the bottom rung 66 of the track 22 between the idler wheel 26 and the trailing roller wheel 28 and (ii) a second segment of the bottom rung 66 of the track 22 between the roller wheels 28 may be greater than or equal to the maximum angle of attack β A In particular, track system 16 may be configured to prevent a significant portion of the first segment of track 22 from engaging the ground and / or supporting vehicle 10. More specifically, in some embodiments, the geometry of track system 24 may prevent idler wheel 26 from supporting a portion of the weight of vehicle 10 to improve durability and avoid deformation and premature deterioration of idler wheel 26 and any components that engage with idler wheel 26.

[0075] In this embodiment, the platform 18 is mounted on the chassis 12 and constitutes the rear end of the vehicle 10, so that the length L of the front overhang portion 72 is FO The length of the rear overhang part 74 L RO Nevertheless, in this embodiment, the payload capacity is not affected by the Regardless of the length of the vehicle 10, the length of the front overhang portion L must be such that the center of gravity remains above the track system 16 when the vehicle 10 is in motion. FO Length of rear overhang L RO For example, in some embodiments, the ratio of the length L of the front overhang portion 72 to the length L of the front overhang portion 72 can be kept relatively small. FO Length L of rear overhang portion 74 RO may be between 1.05 and 1.10. However, this is not required and in some cases the ratio may be between 1 and 1.15, or between 1 and 1.20, or even between 0.95 and 1. That is, rear overhang portion 74 is shorter than front overhang portion 72.

[0076] With reference to a specific numerical example, in one non-limiting embodiment, the maximum rearward attack angle of the vehicle 10 may be about 25°, and the minimum height E of the chassis 12 at the rear overhang portion 74 of the vehicle 10 may be about 25°. C may be the distance between the lowest point of the rear overhang portion 74 of the vehicle 10 and the first plane 97, which may define the minimum height of the rear overhang portion 74, which may be at least 0.60 m (e.g., 0.60 m to 0.90 m), and more specifically, may be about 0.75 m, and the minimum height E over the entire length of the platform 18 P may be about 1.00 m, and the height E of the chassis 12 at the rear end 89 of the chassis 12 C may be about 0.85 m, and the height E of the platform 18 at the rear end of the platform 18 P may be about 1.00 m, and the length L of the rear overhang portion 74 RO may be about 1.00 m.

[0077] In other non-limiting embodiments, the maximum angle of attack of the vehicle 10 in the rearward direction may be at least 15° (e.g., 15° to 35°), more specifically at least 20° (e.g., 20° to 30°), and more specifically at least 25° (e.g., 25° to 27.5°). C The minimum height E of the platform 18 in the rear overhang portion 74 of the vehicle 10 may be at least 0.3 m (e.g., 0.3 m to 1.0 m), more specifically at least 0.6 m (e.g., 0.6 m to 0.9 m). P The height E of the chassis 12 at the rear end 89 of the chassis 12 may be at least 0.6 m (e.g., 0.6 m to 1.4 m), and more specifically, at least 0.9 m (e.g., 0.9 m to 1.1 m). C may be at least 0.6 m (e.g., 0.6 m to 1.1 m), more specifically at least 0.8 m (e.g., 0.8 m to 0.9 m). PThe length L of the rear overhang portion 74 may be at least 0.9 m (e.g., 0.9 m to 1.2 m), and more specifically, at least 1.0 m (e.g., 1.0 m to 1.1 m). RO may be at least 0.8 m (eg, 0.8 m to 1.3 m), more specifically at least 0.9 m (eg, 0.9 m to 1.2 m), and more specifically at least 1.0 m (eg, 1.0 m to 1.1 m).

[0078] The operator cabin 20 may be configured to facilitate operation of the vehicle 10 by the operator. In some embodiments, the operator cabin 20 is configured to allow the operator to have a better view of the terrain 11 while operating the vehicle 10. This may be particularly useful when the vehicle is traveling near a cliff or is being operated at the edge of a cliff. To this end, the operator seat 71 and the steering device 75 (e.g., a steering wheel) may be located to one side of the operator cabin 20, rather than in the center of the width of the operator cabin 20. More specifically, if the operator cabin 20 is on the left side of the chassis, this may be achieved by locating the operator seat 71 and the steering device 75 on the left side of the operator cabin 20 adjacent to a window on the left side of the operator. If the operator cabin 20 is on the right side of the chassis, this may be achieved by locating the operator seat 71 and the steering device 75 on the right side of the operator cabin 20 adjacent to a window on the right side of the operator cabin 20. In this embodiment, the operator cabin 70 further comprises a passenger seat 73 adjacent to the operator seat 71.

[0079] For example, in some embodiments, the distance D between the widthwise center of the operator seat 71 and the outer side edge 491 of the track 22 of the closer one of the track systems 16 in the widthwise direction of the vehicle 10 is Lis less than 1.10 m (e.g., 0.25 m to 1.10 m), in some embodiments less than 0.75 m (e.g., 0.25 m to 0.75 m), and in some embodiments less than 0.40 m (e.g., 0.25 m to 0.40 m); the distance between the widthwise center of the operator seat 71 and the outer side edge 491 of the track 22 of the other track system 16 in the widthwise direction of the vehicle 10 is at least 1.10 m (e.g., 1.10 m to 1.50 m), in some embodiments at least 1.20 m (e.g., 1.20 m to 1.40 m), in some embodiments at least 1.25 m (e.g., 1.25 m to 1.35 m), and in some embodiments even more; and the distance D L In some embodiments, the ratio is less than 0.60 (e.g., 0 to 0.60), less than 0.50 (e.g., 0.10 to 0.50), and in some embodiments, less than 0.40 (e.g., 0.20 to 0.40). Furthermore, in some embodiments, the distance D between the center of the operator seat 70 in the width direction of the vehicle 10 and the first side window 81 is WL may be less than 1 m (e.g., 0.25 m to 1 m), in some embodiments less than 0.65 m (e.g., 0.25 m to 0.65 m), and in some embodiments less than 0.30 m (e.g., 0.25 m to 0.30 m). The distance D between the center of the operator seat 71 in the width direction of the vehicle 10 and the second side window 82 in the width direction of the vehicle 10 may be less than 1 m (e.g., 0.25 m to 0.65 m), and in some embodiments less than 0.30 m (e.g., 0.25 m to 0.30 m). WR may be at least 1 m (e.g., 1 m to 1.50 m), in some embodiments at least 1.10 m (e.g., 1.10 m to 1.40 m), in some embodiments at least 1.20 m (e.g., 1.20 m to 1.30 m), and in some embodiments even greater.

[0080] Of course, when discussing the operator cabin 20, the left and right references can be interchanged if the vehicle is manufactured for a market or customer where the operator is accustomed to sitting and driving on the right side of the vehicle.

[0081] Thus, the foregoing has provided a description of an innovative tracked vehicle comprising a longitudinally extending carbody having forward and rearward end portions defining a length of the carbody, a first track system mounted on a first side of the carbody, and a second track system mounted on a second side of the carbody, each track system having forward and rear ends defining a length of the respective track system, each track system further comprising a track comprising a track having a ground engaging outer surface and an inner surface opposite the ground engaging outer surface, the track comprising a top rung and a bottom rung, the ground engaging outer surface of the bottom rung defining a contact area configured to engage the ground in use, and a track engaging assembly configured to drive and guide the track about the track engaging assembly, the track engaging assembly comprising a plurality of track contacting wheels and a frame supporting each of the track contacting wheels. The vehicle also includes an operator cabin attached to the vehicle body, the operator cabin including an operator interface for allowing an operator of the tracked vehicle to input operator commands for operating the tracked vehicle, and a power train attached to a portion of the vehicle body and including a prime mover. The vehicle body further includes a front overhang portion and a rear overhang portion. Referring further to FIG. 16, the ratio of the vehicle length (LV) to the length (LT) of each track system is 1.25 to 1.75. The entire front overhang portion is on a second plane that passes through a forward end point of the bottom track of the track and defines an angle A of 15° to 30° with a first plane defined by a contact area between the flat ground and the track, and the entire rear overhang portion is on a third plane that passes through a rear end point of the bottom track of the track and defines an angle B of 15° to 35° with the first plane.

[0082] While the illustrated vehicle 10 includes a rigid chassis, in some embodiments, the chassis 12 may include an undercarriage 76 and a superstructure 78 that is movable relative to the undercarriage 76. The undercarriage 76 may be configured to support components of the vehicle 10 that are lower in the height direction of the vehicle 10, such as the track system 16 and at least a portion of the powertrain 15 mounted to the undercarriage 76, and the superstructure 78 may be configured to support components of the vehicle 10 that are higher in the height direction of the vehicle 10, such as the operator cabin 10, the platform 18, and a portion of the powertrain 15 mounted to the superstructure 78.

[0083] In some embodiments, the superstructure 78 may be rotatable relative to the undercarriage 76 about an axis that extends heightwise of the vehicle 10 (i.e., parallel to the steering axis 96). In such embodiments, the vehicle 10 would include a motor for rotating the superstructure 78 relative to the undercarriage 76.

[0084] Although the vehicle 10 is illustrated with a single track system on each side of the vehicle, this is not limiting and in other embodiments there may be two or more track systems on each side of the vehicle.

[0085] In the embodiments discussed above, the vehicle 10 is operable by a user from an operator cabin 20, however, in some embodiments, the vehicle 10 may be remotely operable by a user. In yet other embodiments, the vehicle 10 may be equipped with autonomous capabilities, enabling the vehicle 10 to be semi-autonomous and / or fully autonomous. In some embodiments, the vehicle 10 may not have an operator cabin.

[0086] In the embodiment discussed above, the vehicle 10 is a forwarder, but in other embodiments, some of the above features may be provided on other types of forestry vehicles, agricultural vehicles, industrial vehicles, military vehicles, or other vehicles capable of operating off paved roads. The vehicle 10 may be capable of operating off paved roads, but may also be capable of operating on paved roads in some cases.

[0087] In some examples, any feature of any embodiment described herein can be used in combination with any feature of the other embodiments described herein.

[0088] Certain additional elements required for operation of some embodiments have not been described or shown, as they are assumed to be within the knowledge of those skilled in the art. Furthermore, certain embodiments may function without the inclusion, lack, and / or absence of elements not specifically disclosed herein.

[0089] In the event of any conflict, inconsistency, or other difference between terms used in this specification and terms used in any document incorporated herein by reference, the meaning of the term used in this specification shall control.

[0090] While various embodiments and examples have been presented, they are for purposes of illustration and should not be construed as limiting. Various modifications and enhancements will become apparent to those skilled in the art.

Claims

1. A tracked vehicle, a body extending longitudinally of the tracked vehicle, the body having forward and rearward ends defining a length of the body; a first track system mounted on a first side of the vehicle body and a second track system mounted on a second side of the vehicle body, each track system having a forward end and an aft end defining a length of the respective track system, each track system further comprising: a track including a ground-engaging outer surface and an inner surface opposite the ground-engaging outer surface, the track comprising a top rung and a bottom rung, the ground-engaging outer surface of the bottom rung defining a contact area configured to contact the ground during use; a track-engaging assembly configured to drive and guide the track about the track-engaging assembly, the track-engaging assembly comprising a plurality of track-contacting wheels and a frame supporting each of the track-contacting wheels; the first and second track systems comprising: an operator cabin mounted to the vehicle body, the operator cabin including an operator interface for allowing an operator of the tracked vehicle to input operator commands for operating the tracked vehicle; A power train attached to a part of the vehicle body and including a prime mover; Equipped with The vehicle body includes a front overhang portion and a rear overhang portion, the ratio of the length of said vehicles to the length of each track system is between 1.25 and 1.75; the entirety of the front overhang portion lies on a second plane that passes through a forwardmost end point of the bottom rung of the track and defines an angle of between 15° and 30° with a first plane defined by a contact area of ​​the track with a flat ground surface; the entirety of the rear overhang portion lies on a third plane that passes through a rear-most point of the bottom rung of the track and defines an angle of 15° to 35° with the first plane. The track vehicle.

2. 2. The tracked vehicle of claim 1, wherein a distance between a lowest point of the front overhang portion and the first plane defines a minimum height of the front overhang portion and is between 0.40 m and 0.60 m, and a distance between a lowest point of the rear overhang portion and the first plane defines a minimum height of the rear overhang portion and is between 0.60 m and 0.90 m.

3. 2. The tracked vehicle according to claim 1, wherein the distance between the bottom surface of the front end of the body and the first plane is 0.6 m to 0.9 m.

4. The tracked vehicle according to any one of claims 1 to 3, wherein the distance between the bottom surface of the rear end of the body and the first plane is 0.3 m to 0.6 m.

5. 5. A tracked vehicle according to claim 1, wherein the front overhang portion has a length of 0.7m to 1.3m.

6. 5. A tracked vehicle according to claim 1, wherein the ratio of the length of the front overhang portion to the length of the vehicle is between 0.10 and 0.

25.

7. The tracked vehicle according to any one of claims 1 to 6, wherein the rear overhang portion has a length of 0.7m to 1.3m.

8. 7. A tracked vehicle according to claim 1, wherein the ratio of the length of the rear overhang portion to the length of the vehicle is between 0.10 and 0.

25.

9. A tracked vehicle as described in any one of claims 1 to 8, wherein the center of mass of the tracked vehicle is located in the forwardmost third of the length of the vehicle in the longitudinal direction of the tracked vehicle when the tracked vehicle is unloaded.

10. 10. The tracked vehicle of claim 9, wherein the distance between the front end of the tracked vehicle and the center of mass of the tracked vehicle is between 1.4m and 2.0m in the longitudinal direction of the tracked vehicle.

11. A tracked vehicle as claimed in any preceding claim, wherein part of the operator cabin is longitudinally forward of the forward end of each track system.

12. A tracked vehicle as claimed in any preceding claim, wherein a majority of the operator cabin is longitudinally forward of a front end of the track system.

13. A tracked vehicle as claimed in any preceding claim, wherein part of the power train is longitudinally forward of the forward end of each track system.

14. A tracked vehicle according to any preceding claim, wherein a majority of the power train is longitudinally forward of a forward end of each of the track systems.

15. A tracked vehicle according to any preceding claim, wherein the body is a chassis, and the tracked vehicle comprises a platform mounted on the chassis.

16. The tracked vehicle of claim 15, wherein the platform has a length of between 3.5m and 4.5m.

17. 16. The tracked vehicle of claim 15, wherein the ratio of the length of the platform to the length of each track system is between 0.65 and 1.

05.

18. The platform is 7m ２ ~10m ２ 16. The tracked vehicle of claim 15 having a loading surface area of

19. 16. The tracked vehicle of claim 15, wherein the minimum height of the platform is between 0.6m and 1.4m.

20. The platform is 7m ２ ~10m ２ 16. The tracked vehicle of claim 15, configured to accept a payload of between 6000 kg and 9000 kg over a surface area of ​​1.

21. The tracked vehicle of claim 15 , wherein the platform is movable relative to the chassis.

22. The tracked vehicle of claim 15 , wherein the platform is rotatable relative to the chassis about an axis extending across the width of the tracked vehicle.

23. 23. The tracked vehicle of claim 22 including a motor for rotating the platform about the chassis.

24. The tracked vehicle according to any one of claims 1 to 23, wherein the track-contacting wheels include a drive wheel that drives the track driven by the power train, and at least one idler wheel that guides the track.

25. The tracked vehicle according to any one of claims 1 to 24, wherein the track is a metal embedded rubber track (MERT).

26. The tracked vehicle according to any one of claims 1 to 25, wherein the track is an endless track.

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