Field of the disclosure

The disclosure relates to the vertical transfer of vehicles capable of running on ground level tracks at grade or in tunnel, and also cantilevered from the side of an elevated structure.

Background

Transportation systems for people or goods by vehicles, capable of running on ground level tracks at grade or in tunnel, and also cantilevered from the side of an elevated structure, have been proposed for a number of years. An issue for such transportation systems is the transition between running at ground level tracks and on an elevated structure.

Conventional ramp arrangements require a large amount of space and create areas under the ramp of reduced utility.

Summary of the disclosure

Against this background, there is provided a vertical transfer apparatus for a vehicle. The vehicle comprises a cabin comprising a support wheel on a side of the vehicle configured to engage with a lower running surface beneath the lower support wheel for supporting the vehicle from beneath. The cabin further comprises an upper cantilever wheel assembly on the side of the vehicle configured to bear against an upper guide surface located proximate the side of the vehicle. The cabin further comprises a lower cantilever wheel assembly on the side of the vehicle configured to bear against a lower guide surface located proximate the side of the vehicle. The vehicle is configured to operate in a cantilevered mode from the side of the vehicle. The vertical transfer apparatus comprises a primary track section configured to accommodate the vehicle in the cantilevered mode. The primary track section comprises a lower support track comprising the lower running surface configured to support the lower support wheel on the side of the vehicle, an upper guide surface configured for the upper cantilever wheel assembly to bear against, and a lower guide surface configured for the lower cantilever wheel assembly to bear against. The vertical transfer apparatus further comprises a lift apparatus configured to transfer the primary track section from a first level to a second level, wherein the primary track section is configured to align with an entry portion to a secondary track at the second level, the secondary track being configured to accommodate the vehicle in the cantilevered mode.

In this way a vehicle can be transferred in a cantilevered manner from one level to another, in a compact way.

The lift apparatus may comprise a cable or cables connecting the primary track section to a counterweight.

In this way the vehicle may be lifted by a pulley mechanism.

The lift apparatus may comprise one of a motorised pulley or capstan, a hydraulic lift, a screw lift, or equivalent means.

The lift apparatus may comprise a rotating arm configured to pivot at a first end and attach to the primary track section at a second end.

The entry guide to the primary track section may comprise a portion of the lower support track.

The entry guide to the primary track section may comprise a portion of the upper guide surface.

The entry guide to the primary track section may comprise a portion of the lower guide surface.

In this way the vehicle is able to leave the primary track section and travel away from the vertical transfer apparatus via the secondary track in a cantilevered manner.

On operation of the vehicle in the cantilevered mode, the lower support wheel may be configured to engage with the lower running surface, the upper cantilever wheel assembly may be in its engaged position, and the lower cantilever wheel assembly may be in its engaged position. In this way, the vehicle may operate in a cantilevered manner on both sides of the vehicle without bottom support.

The lower support wheel may be on a first side of the vehicle and the lower support wheel may be configured to engage with a first lower running surface. The vehicle may further comprise a second lower support wheel on a second side of the vehicle configured to engage with a second lower running surface beneath the second lower support wheel for supporting the vehicle from beneath.

The vehicle may be further configured to operate in a bottom support mode, wherein on operation of the vehicle in bottom support mode wherein the first lower support wheel and the second lower support wheel are supported.

In this way the vehicle may be able to operate on both cantilevered track and bottom support track

The upper cantilever wheel assembly may be a first cantilever wheel assembly on a first side of the vehicle, having: an engaged position wherein it is configured to bear against a first upper guide surface proximate the first side of the vehicle; and a retracted position for disengagement from the first upper guide surface. The lower cantilever wheel assembly may be a first lower cantilever wheel assembly on the first side of the vehicle, having: an engaged position wherein it is configured to bear against a first lower guide surface located proximate the first side of the vehicle; and a retracted position for disengagement from the first lower guide surface. The upper guide surface may be a first upper guide surface located proximate to the first side of the vehicle, and the lower guide surface may be a first lower guide surface located proximate to the first side of the vehicle. The vehicle may further comprise a second upper cantilever wheel assembly on the second side of the vehicle having: an engaged position wherein it is configured to bear against a second upper guide surface located proximate the second side of the vehicle; and a retracted position for disengagement from the second upper guide surface. The vehicle may further comprise a second lower cantilever wheel assembly on the second side of the vehicle having: an engaged position wherein it is configured to bear against a second lower guide surface located proximate the second side of the vehicle; and a retracted position for disengagement from the second lower guide surface. The vehicle may be configured to operate in an opposite cantilevered mode, wherein the second lower support wheel is supported.

In this way the vehicle may be able to operate in a cantilevered manner from either side of the vehicle.

On operation of the vehicle in the opposite cantilevered mode the second lower support wheel may be configured to engage with the second lower running surface, the second upper cantilever wheel assembly may be in its engaged position, and the second lower cantilever wheel assembly is in its engaged position.

On operation of the vehicle in either the bottom support mode or the opposite cantilevered mode the second lower support wheel may be configured to engage with the second lower running surface.

On operation of the vehicle in the bottom support mode the first and second lower support wheels may be configured to engage with the first and second lower running surfaces respectively.

The vertical transfer apparatus may further comprise a tertiary track section configured to accommodate the vehicle in the bottom support mode, the tertiary track section comprising a first and second lower support track comprising the first and second lower running surfaces. The vertical transfer apparatus may further comprise a junction comprising a first lower support track configured to support the first lower support wheel, a second lower support track configured to support the second lower support wheel, an entry guide to the primary track section, and an entry guide to the tertiary track section.

In this way the vehicle may be directed either to the primary track section in order to be transferred from the first level to the second level, or to the tertiary track section in bottom support mode.

The vertical transfer apparatus may further comprise a tertiary track section configured to accommodate the vehicle in the opposite cantilevered mode, the tertiary track section comprising a second lower support track comprising the second lower running surface, a second upper guide surface and a second lower guide surface. The vertical transfer apparatus may further comprise a junction comprising a first lower support track configured to support the first lower support wheel a second lower support track configured to support the second lower support wheel, an entry guide to the primary track section, and an entry guide to the tertiary track section.

In this way the vehicle may be directed either to the primary track section in order to be transferred from the first level to the second level, or to the tertiary track in opposite cantilevered mode.

The vertical transfer apparatus may further comprise a tertiary track section configured to accommodate the vehicle in the cantilevered mode. The vertical transfer apparatus may further comprise a junction comprising a first lower support track configured to support the first lower support wheel, a second lower support track configured to support the second lower support wheel, an entry guide to the primary track section, and an entry guide to the tertiary track section.

In this way the vehicle may be directed either to the primary track section in order to be transferred from the first level to the second level, or to the tertiary track section.

Route selection at the junction between the primary track section and the tertiary track section may be determined by configurations of the first upper cantilever wheel assembly, the first lower cantilever wheel assembly, the second upper cantilever wheel assembly, and the second lower cantilever wheel assembly.

The entry guide to the tertiary track section may comprise a portion of a second upper guide surface.

The entry guide to the tertiary track section may comprise a portion of a second lower guide surface.

The entry guide to the tertiary track section may comprise a portion of a second lower support surface.

In this way, the vehicle may be directed along either the primary or tertiary track sections by choosing which of the cantilevered wheel assemblies are engaged. At the junction, selection between the primary track section and the tertiary track section may be effected for the primary track section, by adopting: the engaged position of the first upper cantilever wheel assembly; the engaged position of the first lower cantilever wheel assembly; the disengaged position of the second upper cantilever wheel assembly; and the disengaged position of the second lower cantilever wheel assembly. At the junction, selection between the primary track section and the tertiary track section may be effected for the tertiary track section, by adopting: the engaged position of the second lower cantilever wheel assembly.

At the junction, selection between the primary track section and the tertiary track section may be effected for the primary track section, by adopting: the engaged position of the second upper cantilever wheel assembly; the engaged position of the second lower cantilever wheel assembly; the disengaged position of the first upper cantilever wheel assembly. At the junction, selection between the primary track section and the tertiary track section may be effected for the tertiary track section, by adopting: the engaged position of the first lower cantilever wheel assembly.

In this way, the vehicle may be directed either to the primary track section to be transferred from the first level to the second level, or to the tertiary track.

Brief description of the drawings

A specific embodiment of the disclosure will now be described, by way of example only, with reference to the accompanying drawings in which:

Figure 1 shows a schematic view of a vehicle in accordance with the disclosure when operating in a first mode, whereby it is cantilevered from the left side;

Figure 2 shows a schematic view of the vehicle of Figure 1 when operating in a second mode, whereby it cantilevered from the right side;

Figure 3 shows a schematic view of the vehicle of Figures 1 and 2 when operating in a third mode, whereby is supported from beneath without being cantilevered; Figure 4 shows a schematic view of a part of a track system in accordance with the disclosure configured for left side cantilever running;

Figure 5 shows a schematic view of a part of a track system in accordance with the disclosure configured for right side cantilever running;

Figure 6 shows a schematic view of a part of a track system in accordance with the disclosure configured for bottom support running;

Figure 7 shows a schematic view of a vehicle in accordance with the disclosure when operating in a first mode, whereby it is cantilevered from the left side at an elevated level;

Figure 8 shows a schematic view of the vehicle of Figure 7 being transferred between an elevated level and ground level via, by way of example, a counterweight system. Figure 8A shows the vehicle at the elevated level. Figure 8B shows the vehicle between levels. Figure 8C shows the vehicle at a lower level.

Figure 9 shows a schematic view of the cantilevered track of Figure 4 or 5 being transferred between an elevated level and ground level via a rotating arm;

Figure 10 shows a schematic view of the vehicle of Figures 1 to 3 when transitioning from bottom support at a junction where both left and right cantilever support route options are available and showing the configuration of wheel deployments for left route selection;

Figure 11 shows the same vehicle and junction as Figure 10 but with the configuration of wheel deployments for right route selection;

Figure 12 shows a schematic plan view of a part of a track system in accordance with the disclosure on approach to and through a bottom support junction (with no cantilever operation on either side of the junction);

Figure 13 shows a schematic view of a part of a track system in accordance with the disclosure on approach to a junction, at section A-A identified in Figure 12; Figure 14 shows the configuration of wheel deployments for left route selection on approach to the bottom support junction of Figures 10 and 11 ;

Figure 15 shows the configuration of wheel deployments for right route selection on approach to the bottom support junction of Figures 10 and 11 ;

Figure 16 shows a schematic plan view of a part of a track system in accordance with the disclosure on approach to and through a junction.

Figure 17 shows a schematic plan view of a part of a track system in accordance with the disclosure on approach to and through a junction.

Figure 18 shows a vehicle in accordance with Figures 1 to 3 and identifies more of the details of the wheel assemblies with the addition of further reference numerals.

Detailed description

Vehicles designed to run at both ground level ‘bottom support’ and cantilevered from the side of a structure ‘side support’ require guide wheels, or equivalent means, acting on a suitable guide surface, to keep the vehicle positioned on its track when operating on bottom support, and to counter the moment exerted by the mass of the vehicle when travelling on side support. Such guide wheels may be rubber-tyred and such equivalent means may be a flange on a steel wheel, or a hard-wearing, low-friction, means such as a magnetic counter-force or an air pressure cushion.

In a cantilevered mode, the vehicle is cantilevered from a side of the vehicle. The cantilevered mode may be a first mode, in which the vehicle is cantilevered from a left side. The cantilevered mode may be a second mode, in which the vehicle is cantilevered from a right side. In a third mode the vehicle is supported from beneath without being cantilevered. The vehicle may be configured to operate in the third mode and in at least one of the first mode and second mode.

Figure 1 shows the vehicle operating in the first mode; Figure 2 shows the vehicle operating in the second mode; and Figure 3 shows the vehicle operating in the third mode. Referring to Figures 1 to 3, a vehicle 100 in accordance with the disclosure comprises a left lower support wheel 210 on the left side 200 of the vehicle 100 and a right lower support wheel 310 on the right side of the vehicle. In many embodiments, there may be a plurality of left lower support wheels 210 and a plurality of right lower support wheels 310.

The left lower support wheel 210 is configured to engage with a left lower running surface 410 beneath the left lower support wheel 210 for supporting the vehicle 100 from beneath and the right lower support wheel 310 is configured to engage with a right lower running surface 510 beneath the right lower support wheel 310 for supporting the vehicle 100 from beneath. The left and right lower running surfaces 410, 510 may be substantially horizontal.

The vehicle 100 also comprises a left upper cantilever wheel assembly 230 on the left side of the vehicle 100 and a right upper cantilever wheel assembly 330 on the right side 300 of the vehicle 100. In many embodiments, there may be a plurality of left upper cantilever wheel assemblies 230 and a plurality of right upper cantilever wheel assemblies 330.

The term “wheel assembly” is used throughout this document to refer to an assembly comprising a mounting and a wheel rotatably mounted to the mounting. Wheel assembly components are described further below with reference to Figure 18.

The vehicle 100 also comprises a left lower cantilever wheel assembly 250 on the left side 200 of the vehicle 100 and a right lower cantilever wheel assembly 350 on the right side 300 of the vehicle 100. In many embodiments, there may be a plurality of lower cantilever wheel assemblies 250 and a plurality of right lower cantilever wheel assemblies 350.

The left upper cantilever wheel assembly 230 has: an engaged position wherein it is configured to bear against a left upper guide surface 430 located proximate the left side 200 of the vehicle 100; and a retracted position for disengagement from the left upper guide surface 430. Similarly, the right upper cantilever wheel assembly 330 has: an engaged position wherein it is configured to bear against a right upper guide surface 530 located proximate the right side 300 of the vehicle 100; and a retracted position for disengagement from the right upper guide surface 530. The left and right upper guide surfaces 430, 530 may be substantially vertical.

The left lower cantilever wheel assembly 250 has: an engaged position wherein it is configured to bear against a left lower guide surface 450 located proximate the left side 200 of the vehicle 100; and a retracted position for disengagement from the left lower guide surface 450. Similarly, the right lower cantilever wheel assembly 350 has: an engaged position wherein it is configured to bear against a right lower guide surface 550 located proximate the right side 300 of the vehicle 100; and a retracted position for disengagement from the right lower guide surface 550.

The left and right lower guide surfaces 450, 550 may be substantially vertical.

In the first mode, as shown in Figure 1 , both the left upper cantilever wheel assembly 230 and the left lower cantilever wheel assembly 250 are in the engaged position and both the right upper cantilever wheel assembly 330 and the right lower cantilever wheel assembly 350 are in the retracted position.

In the second mode, as shown in Figure 2, both the right upper cantilever wheel assembly 330 and the right lower cantilever wheel assembly 350 are in the engaged position and both the left upper cantilever wheel assembly 230 and the left lower cantilever wheel assembly 250 are in the retracted position.

In the third mode, as shown in Figure 3, both left and right lower support wheels 210, 310 are supported by respective left and right lower running surfaces 410, 510 simultaneously. In addition, the left lower cantilever wheel assembly 250 and the right lower cantilever wheel assembly 350 are in their engaged positions.

By providing engagable and retractable upper and lower cantilever wheel assemblies on both sides of the vehicle, it is possible to deploy the engagable and retractable functionality of the wheel assemblies in order to effect route selection at a junction without requiring moving parts at the junction. This will be explained further below after an introduction to the track system. Turning to the track system, there may be sections of left cantilever track as shown schematically in Figure 4, sections of right cantilever track as shown schematically in Figure 5 and sections of bottom support as shown schematically in Figure 6.

Referring to Figure 4, in left cantilever track sections 400, the track system comprises a left support structure 480 comprising the left upper guide surface 430, the left lower running surface 410 and the left lower guide surface 450.

Referring to Figure 5, in right cantilever track sections 500, the track system comprises a right support structure 580 comprising the right upper guide surface 530, the right lower running surface 510 and the right lower guide surface 550.

Referring to Figure 6, in bottom support track sections 600, the track system comprises the left lower running surface 410, the left lower guide surface 450, the right lower running surface 510 and the right lower guide surface 550.

In order to transfer one or more cabins of the vehicle between a lower level section of track and section of track at another level, wherein the section of track at one of the levels comprises a left cantilever track section 400 or a right cantilever track section 500, a primary track section is transferred between a first level and a second level. The first level may be above or below the second level. The primary track section may be transferred from the first level to the second level, and/or from the second level to the first level. The primary track section comprises either a left cantilever track section 400 or a right cantilever track section 500. The primary track section comprises a lower support track comprising the lower running surface configured to support the lower support wheel on the side of the vehicle; an upper guide surface configured for the upper cantilever wheel assemblies to bear against; and a lower guide surface configured for the lower cantilever wheel assembly to bear against.

A lift apparatus is configured to transfer the primary track section from a first level to a second level, wherein the primary track section is configured to align with an entry portion to a secondary track at the second level. The secondary track may comprise a cantilevered track section that is cantilevered on the same side as the primary section. The secondary track may comprise left cantilever track, right cantilever track or, if lower than the primary track, bottom support track. The first level may be higher than the second level, or the first level may be lower than the second level. The vehicle may approach the primary track section via track comprising either left cantilever track, right cantilever track or bottom support track.

By way of example, with reference to Figure 7, the lift apparatus will be described here for a primary track section comprising a left cantilevered track section 400. Alternatively, the lift apparatus may be configured to transfer a primary track section that comprises a right cantilevered track section 500. Referring again to Figure 7, the vehicle is shown in the first mode on a left cantilevered track section 400 that is elevated at a first level 700 at the top of a support 800. In an embodiment, the lift apparatus may be configured to transfer the vehicle from the first level 700 to the second level 900, the second level 900 being at the bottom of the support 800. The primary track section is configured to align with an entry portion to a secondary track at the second level 900. In another embodiment, the lift apparatus may be configured to transfer the vehicle from the second level 900 to the first level 700. The primary track section is configured to align with an entry portion to a tertiary track section at the first level 700.

The lift apparatus may transfer the primary track section in a vertical manner. The lift apparatus may operate via a powered counterweight system (comprising, for example, a pulley or capstan), hydraulics, a motor, a screw lift, or other means. With reference to Figure 8, an example of a primary track section being transferred from the first level 700 to the second level 900 is shown. The primary track section comprises a left cantilevered track section 400 by way of example but may be a right cantilevered track section 500. The primary track section is connected via a cable 1010 to a counterweight 1020 wherein the cable passes over a pulley 1030. By way of example only, the counterweight 1020 is shown to be on the opposite side of the support 800 from the primary track section. Figure 8A shows the primary track section at the first level 700 and the counterweight 1020 at the second level 900. Figure 8C shows the primary track section at the second level 900 and the counterweight 1020 at the first level 700. Figure 8B shows an intermediate position between Figures 8A and 8C.

In another embodiment, the lift apparatus may transfer the primary track section in a manner that lateral as well as vertical motion, for example by rotation. With reference to Figure 9, the lift apparatus may transfer the primary track section via a rotating arm 1110 that rotates from a rotation point 1120 that may be at a first end of the rotating arm 1110. The primary track section may be attached to a second end of the rotating arm 1110. In another embodiment, the rotation point 1120 may be at the centre of the rotating arm 1110, with a counterweight at a first end of the rotating arm 1110 and the primary track section at a second end of the rotating arm 1110. The primary track section in Figure 9 is shown as a left cantilevered track section 400, but could also be a right cantilevered track section. For simplicity, only the upper guide surface 430 is shown (with the vehicle 100 indicated by dashed lines) but clearly the whole left cantilevered track section 400 would be transferred by the rotating arm 110.

There may be junctions in the track at the first level where the vehicle may be directed towards the primary track section in order to be transferred from the first level to the second level, or towards a tertiary track section at the first level. The track approaching the junction may be bottom support (for third mode running) or either left cantilever support (first mode running) or right cantilever support (right mode running). The tertiary track section may be bottom support (for third mode running) to either left cantilever support (first mode running) or right cantilever support (right mode running).

There may be junctions in the track where the track transitions from bottom support (for third mode running) to either left cantilever support (first mode running) or right cantilever support (right mode running).

Such junctions may provide for both the left upper guide surface 430 and the right upper guide surface 530 in the approach to the junction in addition to both the left lower running surface 410 and the right lower running surface 510.

Prior to the introduction of the left upper guide surface 430 and the right upper guide surface 530, route selection is determined by selection of one (but not both) of the left upper cantilever wheel assembly 230 (for left route selection) or the right upper cantilever wheel assembly 330 (or right route selection).

Figure 10 shows the configuration of wheel deployment for a left turn at such a junction.

More specifically, Figure 10 shows the vehicle in situ on the track assembly in the approach to the junction at a point where both left and right upper guide surfaces 430, 530 are in place. Prior to the start of the left and right upper guide surfaces 430, 530, the left upper cantilever wheel assembly 230 has been engaged but not the right upper cantilever wheel assembly 330 such that, at the start of the left upper guide surface 430, the left upper cantilever wheel assembly 230 bears against the left upper guide surface 430. Then, once cantilever support is in place from both the left upper cantilever wheel assembly 230 and the left lower cantilever wheel assembly 250, the right lower cantilever wheel assembly 350 is retracted (so as to adopt the position shown in Figure 10). In this way, as the left and right upper guide surfaces 430, 530 diverge at the junction, the vehicle cantilevers from the left upper guide surface 430 and the left lower guide surface 450 and thereby follows the left route option at the junction.

Figure 11 shows the configuration of wheel deployment for a right turn at such a junction.

Figure 11 shows the vehicle in situ on the track assembly in the approach to the junction at a point where both left and right upper guide surfaces 430, 530 are in place - that is exactly the same location as Figure 10, but with wheel selection for right route selection. Prior to the start of the left and right upper guide surfaces 430, 530, the right upper cantilever wheel assembly 330 has been engaged but not the left upper cantilever wheel assembly 230 such, at the start of the right upper guide surface 530, the right upper cantilever wheel assembly 330 bears against the right upper guide surface 530. Then, once cantilever support is in place from both the right upper cantilever wheel assembly 330 and the right lower cantilever wheel assembly 350, the left lower cantilever wheel assembly 250 is retracted (so as to adopt the position shown in Figure 11). In this way, as the left and right upper guide surfaces 430, 530 diverge at the junction, the vehicle cantilevers from the right upper guide surface 530 and the right lower guide surface 550 and thereby follows the right route option at the junction.

A different type of junction is shown in Figures 12 and 13, specifically a junction 1200 that employs only first mode (bottom support) operation on both sides of the junction. Figure 12 shows a plan view while Figure 13 shows a view equivalent to that shown in Figures 4, 5 and 6.

In the vicinity of the junction 1200, the track system may comprise a left security guide surface 455 parallel to the left lower guide surface 450. Similarly, the track system may also comprise a right security guide surface 555 parallel to the right lower guide surface 550. The purpose of the left security guide surface 455 and the right security guide surface 555 may be to provide a correctional bearing surface for contact by one of the left and right lower cantilever wheel assemblies 250, 350 should the vehicle begin to deviate from the selected path.

Importantly, as evident from Figure 12, there is a break in the intersecting lower guide surfaces at the point of intersection 1210 in order to facilitate passage of the lower guide wheels on the side of the vehicle opposite to the side to which the vehicle is tuning.

The section A-A identified in Figure 12 is illustrated in Figure 13. This illustrates the locations of the left security guide surface 455 and the right security guide surface 555 in particular, on the approach to the junction 1200.

As already discussed, in anticipation of a junction, route selection by the vehicle 100 is effected by appropriate deployment and retraction of particular guide wheels.

For the junction shown in Figures 12 and 13, vehicle wheel deployment for left route selection is illustrated in Figure 14. As shown, the right lower cantilever wheel assembly 350 is in the engaged (deployed) position; all other guide wheel assemblies are in the retracted (disengaged) position.

In this way, the right lower cantilever wheel 353 of the right lower cantilever wheel assembly 350 sits between the right lower guide surface 550 and the right security guide surface 555 and bears against the right lower guide surface 550 thus acting to guide the vehicle along the left route option.

For the junction shown in Figures 12 and 13, vehicle wheel deployment for right route selection is illustrated in Figure 15. As shown, the left lower cantilever wheel assembly 250 is in the engaged (deployed) position; all other guide wheel assemblies are in the retracted (disengaged) position.

In this way, the left lower cantilever wheel 253 of the left lower cantilever wheel assembly 250 sits between the left lower guide surface 450 and the left security guide surface 455. The left lower cantilever wheel 253 bears against the left lower guide surface 450 and bears against the left security guide surface 455 thus acting to guide the vehicle along the right route option.

A tapered or angled section may be present at a first end of one or more of the first upper guide surface; the first upper guide surface; the first lower guide surface; and the second lower guide surface to facilitate gentle transition between running modes.

The entry and exit surfaces may also be arranged to be of low-frictional material to minimise skidding shock as the guide wheels initially engage with the entry or exit guide surfaces.

Figures 16 and 17 show further examples of junctions, and indicate the primary track section by a dashed box.

The example of Figure 16 may comprise a left security guide surface 455 parallel to the left lower guide surface 450. Similarly, the track system may also comprise a right security guide surface 555 parallel to the right lower guide surface 550. The left lower cantilever wheel assembly 250 may be in the engaged (deployed) position to guide the vehicle along the left route option. The right lower cantilever wheel assembly 350 may be in the engaged (deployed) position to guide the vehicle along the right route option. The left route option may lead to left cantilevered track, and the right route option may lead to either bottom support or right cantilevered track. The left route option guides the vehicle to the primary track section, shown as a left cantilevered track section 400.

The example of Figure 17 may comprise a left security guide surface 455 parallel to the left lower guide surface 450. Similarly, the track system may also comprise a right security guide surface 555 parallel to the right lower guide surface 550. The left lower cantilever wheel assembly 250 may be in the engaged (deployed) position to guide the vehicle along the right route option. The right lower cantilever wheel assembly 350 may be in the engaged (deployed) position to guide the vehicle along the left route option. The left route option may lead to right cantilevered track, and the right route option may lead to either bottom support or left cantilevered track. The left route option guides the vehicle to the primary track section, shown as a right cantilevered track section 500. In another embodiment, the vehicle may approach a junction in the first or second mode, wherein the approach to the junction comprises either a left cantilevered track section 400 or a right cantilevered track section.

Figure 18 focuses on the wheel assemblies and their components. Figure 18 shows a vehicle with wheel deployment when in right cantilever (second mode) operation.

The left and right upper cantilever wheel assemblies each comprise a lateral arm 231 , 331 , a vertical axle 232, 332 and a wheel 233, 333 mounted on the vertical axle 232, 332. Each wheel 233, 333 rotates in a substantially horizontal plane.

The left and right lower cantilever wheel assemblies 250, 350 each comprise a vertical axle 252, 352 and a wheel 253, 353 rotatably mounted on the vertical axle 252, 352. Each wheel 253, 353 rotates in a substantially horizontal plane.

As already explained, each of the left upper cantilever wheel assembly 230, the right upper cantilever wheel assembly 330, the left lower cantilever wheel assembly 250 and the right lower cantilever wheel assembly 350 has an engaged (deployed) position and a retracted (disengaged) position. A variety of different mechanisms are envisaged for deployment and retraction.

First, considering first the left and right upper cantilever wheel assemblies 230, 330, in some embodiments, such as the illustrated embodiments, the left and right upper cantilever wheel assemblies 230, 330 (that is the entire wheel assembly rather than just the wheel) may translate laterally between deployed and retracted positions. This lateral movement may be substantially horizontal.

In other embodiments (not illustrated) the left and right upper cantilever wheel assemblies 230, 330 may translate up or down between deployed and retracted positions. This translational movement may be substantially vertical.

In still other embodiments (not illustrated), the left and right upper cantilever wheel assemblies 230, 330 may rotate between deployed and retracted positions. Secondly, considering the left and right lower cantilever wheel assemblies 250, 350, in some embodiments, such as the illustrated embodiment, the left and right lower cantilever wheel assemblies 250, 350 (that is the entire wheel assembly rather than just the wheel) may translate up or down between deployed and retracted positions. This translational movement may be substantially vertical.

In other embodiments, the left and right lower cantilever wheel assemblies 250, 350 may translate laterally between deployed and retracted positions. This lateral movement may be substantially horizontal.

In still other embodiments (not illustrated), the left and right lower cantilever wheel assemblies 250, 350 may rotate between deployed and retracted positions.