Flywheel assemblies and vehicles including same

A vehicle includes a frame, an engine, a steering assembly, a steerable wheel, a flywheel assembly, and a controller. The frame has a front end and a rear end and defines a roll axis extending between the front end and the rear end. The engine is supported by the frame. The steering assembly is pivotally coupled with the frame and is pivotable about a steering axis. The steerable wheel is rotatably coupled with the steering assembly. The flywheel assembly comprises an inertial mass and is coupled with the frame. The inertial mass is rotatable about a flywheel axis. The controller is in communication with the flywheel assembly and is configured to facilitate rotation of the inertial mass in one of a counterclockwise direction and a clockwise direction in response to pivoting of the steering assembly in a leftward direction and a rightward direction, respectively. Methods are also provided.

TECHNICAL FIELD

A flywheel assembly is provided on a vehicle. The flywheel assembly can include a rotatable inertial mass configured to selectively exert roll moments upon the vehicle.

BACKGROUND

A vehicle, such as a motorcycle, can include a pivotable steering assembly that rotatably supports a steerable wheel. During operation of the motorcycle, it may be necessary countersteer the pivotable steering assembly to initiate turning of the motorcycle.

SUMMARY

In accordance with one embodiment, a vehicle comprises a frame, an engine, a steering assembly, a steerable wheel, a flywheel assembly, and a controller. The frame has a front end and a rear end and defines a roll axis extending between the front end and the rear end. The engine is supported by the frame. The steering assembly is pivotally coupled with the frame and is pivotable about a steering axis. The steerable wheel is rotatably coupled with the steering assembly. The flywheel assembly comprises an inertial mass and is coupled with the frame. The inertial mass is rotatable about a flywheel axis. The controller is in communication with the flywheel assembly and is configured to facilitate rotation of the inertial mass in one of a counterclockwise direction and a clockwise direction in response to pivoting of the steering assembly in a leftward direction and a rightward direction, respectively.

In accordance with another embodiment, a method for operating a motorcycle is provided. The motorcycle comprises a flywheel assembly having an inertial mass that is rotatable about a flywheel axis. The method comprises detecting pivoting of a steering assembly of the motorcycle in one of a leftward direction and a rightward direction, and rotating the flywheel assembly in one of a counterclockwise direction and a clockwise direction in response to pivoting of the steering assembly in one of a leftward direction and a rightward direction, respectively.

In accordance with yet another embodiment a motorcycle comprises a frame, an engine, a steering assembly, a steerable wheel, a flywheel assembly, a controller, a steering assembly sensor, and a frame. The frame has a front end and a rear end and defines a roll axis extending between the front end and the rear end. The engine is supported by the frame. The steering assembly is pivotally coupled with the frame and is pivotable about a steering axis. The steerable wheel is rotatably coupled with the steering assembly. The flywheel assembly comprises an inertial mass and is coupled with the frame. The inertial mass is rotatable about a flywheel axis. The controller is in communication with the flywheel assembly. The steering assembly sensor is associated with the steering assembly and is in communication with the controller. The steering assembly sensor is configured to detect pivoting of the steering assembly. The controller is configured to facilitate rotation of the inertial mass in one of a counterclockwise direction and a clockwise direction in response to pivoting of the steering assembly in a leftward direction and a rightward direction, respectively. The controller is also configured to inhibit rotation of the flywheel when the steering assembly is provided in a substantially straight-forward position and to control an angular velocity of the flywheel according to a speed of the motorcycle and a position of the steering assembly.

DETAILED DESCRIPTION

The present invention and its operation are hereinafter described in detail in connection with the views and examples ofFIGS. 1-4, wherein like numbers indicate the same or corresponding elements throughout the views. A motorcycle10includes a flywheel assembly12, as described in further detail below. The flywheel assembly12can be provided on any of a variety of other suitable two-wheeled vehicles, such as a scooter, or a bicycle, for example. In one embodiment, as illustrated inFIG. 1, the motorcycle10can include an engine14that can comprise an internal combustion engine, a turbine-type engine, or any of a variety of other suitable type of engine. The engine14can be configured to consume gasoline, diesel fuel, biodiesel, propane, natural gas, ethanol, hydrogen, and/or any of a variety of other suitable fuels or combination thereof. In alternative embodiments, in lieu of an engine or in addition to an engine, a vehicle can include an electric motor or a pair of mechanical foot pedals, for example.

As illustrated inFIG. 1, the motorcycle10can include a frame16, a front wheel18and a rear wheel20. The frame can extend between a front end17and a rear end19. The engine14can be coupled with the frame16of the motorcycle10and can be configured to generate mechanical power for transmission to the front and/or rear wheels18,20of the motorcycle10. The motorcycle10can include a steering assembly22having a pair of handlebars24coupled with a front fork26. The front wheel18can comprise a steerable wheel that can be rotatably coupled to the front fork26. The steering assembly22can be pivotally coupled with the frame16such that the steering assembly22is pivotable about a steering axis A1. To steer the motorcycle10, the steering assembly22can be pivoted with respect to the frame16through actuation of the handlebars24by an operator (not shown) seated upon a seat28supported by the frame16of the motorcycle10. The rear wheel20can be rotatably supported with respect to the frame16by a swing member30.

In one embodiment as shown generally inFIG. 1, the flywheel assembly12can be coupled to the frame16between the frame16and the front wheel18. The flywheel assembly12can be mounted forwardly of a frame-mounted radiator31. During operation of the motorcycle10, ambient air intended to pass across the frame-mounted radiator31can facilitate cooling of the flywheel assembly12. The flywheel assembly12can accordingly include heat fins or some other heat-sink arrangement to facilitate more effective cooling of the flywheel assembly12. It will be appreciated that the flywheel assembly12can be positioned at any of a variety of suitable locations upon the motorcycle10. For example, in an alternative embodiment, a flywheel assembly can be positioned beneath the seat28. It will be appreciated that the positioning of a flywheel assembly upon a vehicle, such as a motorcycle, can be selected based upon optimization of vehicular space, cost, and weight considerations.

As illustrated inFIG. 2, the motorcycle10can define a roll axis Ar. As illustrated inFIG. 3, the flywheel assembly12can include an inertial mass32that is configured to rotate about a spin axis A2. The flywheel assembly12can be oriented on the motorcycle10such that the spin axis A2of the inertial mass32lies substantially parallel with the roll axis Ar of the motorcycle10. In one embodiment, the flywheel assembly12can be oriented on the motorcycle10such that the spin axis A2of the inertial mass32is coaxial with the roll axis Ar of the motorcycle10. In either of these arrangements, a nutation axis (not shown) of the inertial mass32can be substantially coaxial or parallel with a pitch axis Ap (FIG. 2), and a precession axis (not shown) of the inertial mass32can be substantially coaxial or parallel with a yaw axis Ay (FIG. 2).

The inertial mass32can be configured for selective rotation during operation of the motorcycle10. In one embodiment, the flywheel assembly12can be configured as a flywheel battery (e.g., a flywheel energy storage device) such that the inertial mass32is rotated with electrical energy. Typically, a flywheel battery is used to store electrical energy as rotational energy. Therefore, as illustrated inFIG. 3, the inertial mass32can be rotatably supported within a containment unit34that includes a stator36. The stator36can be disposed along an internal wall38of the containment vessel34such that it is disposed between the inertial mass32and the containment vessel34. The inertial mass32can be configured as a rotor such that the inertial mass32can electromagnetically interact with the stator36in a manner typical of a conventional brushless DC motor or AC induction motor, or any manner of synchronous electrical machines familiar in the art.

Rotation of the inertial mass32can be a function of stored electrical energy. When electrical energy is imparted to the stator36to charge the flywheel assembly12, the angular velocity of the inertial mass32can increase. However, when electrical energy is discharged from the flywheel assembly12(e.g., an electrical load is coupled to the flywheel assembly12), the angular velocity of the inertial mass32can be decreased.

The containment vessel34may be a type of vacuum vessel, for example. The containment vessel34can be associated with a vacuum pump (not shown) to facilitate creation of a vacuum within the containment vessel34. Creation of a sufficient vacuum within the containment vessel34can facilitate improved efficiency and reduced friction losses during rotation of the inertial mass32. The inertial mass32can additionally or alternatively be rotatably supported within the containment vessel34by bearings (e.g., high efficiency bearings such as mechanical bearings or magnetic bearings) that can further improve efficiency and reduced friction losses during rotation of the inertial mass32.

As illustrated inFIG. 3, the flywheel assembly12can be in communication with a controller40that can be configured to control the angular velocity and/or direction of the inertial mass32. In one embodiment, the controller40can include power electronics (e.g., transistors, thyristors, source controlled rectifiers, or insulated gate bipolar transistors) that facilitate control of the direction of rotation of the inertial mass32. In particular, the power electronics can be configured to selectively apply opposing electrical energy fields within the flywheel assembly12to change the direction of the inertial mass32. It will be appreciated that the power electronics can also be configured to decelerate the inertial mass32(e.g., through electronic braking) prior to changing its rotational direction. When the controller40initiates a change in the direction of the inertial mass32, the power electronics can decelerate the inertial mass32to rest and can then apply an electrical energy field that rotates the inertial mass32in an opposite direction. Deceleration corresponds to a generator mode, whereby mechanical energy is converted to electrical energy. Rotation of the inertial mass32can impart a roll moment upon the motorcycle10that is proportional with the angular velocity and direction of the inertial mass32. During operation of the motorcycle10, this roll moment can affect leaning of the motorcycle10.

The motorcycle10can include a steering assembly sensor42and a lean angle sensor44, as illustrated inFIG. 1. Each of the steering assembly sensor42and the lean sensor44can be in communication with the controller40, as illustrated inFIG. 3. The steering assembly sensor42can facilitate detection of the steering position of the steering assembly22. Although the steering assembly sensor42is shown to be mounted adjacent to the steering assembly22, it will be appreciated that a steering assembly sensor can be provided in any of a variety of suitable alternative locations on a motorcycle. In one embodiment, the steering assembly sensor42can comprise a rotary encoder, but in other embodiments, the steering assembly sensor42can comprise any of a variety of suitable alternative arrangements for detecting a position of the steering assembly22. The lean angle sensor44can facilitate detection of the lean angle of the motorcycle10relative to a ground surface, such as when the motorcycle is leaning to navigate a turn. Although the lean angle sensor44is shown to be located beneath the seat28, it will be appreciated that a lean angle sensor44can be provided in any of a variety of suitable alternative locations on a motorcycle. In one embodiment, the lean angle sensor44can comprise a gyroscope-based pitch sensor, but in other embodiments, the lean angle sensor44can comprise any of a variety of suitable alternative arrangements for detecting the lean angle of a motorcycle relative to a ground surface.

The motorcycle10can also include a vehicular speed sensor46that is in communication with the controller40, as illustrated inFIGS. 1 and 3. In one embodiment, the vehicular speed sensor46can comprise a wheel speed sensor mounted to the rear swing arm30adjacent the rear wheel20. However, a vehicular speed sensor can comprise any of a variety of suitable alternative arrangements for detecting a speed of a motorcycle, such as through use of a global positioning system.

It will be appreciated that when the motorcycle10is operating above a certain speed (e.g., 15 M.P.H), steering the motorcycle10through a turn can be achieved by first countersteering the motorcycle10. For example, to steer the motorcycle10into a right turn, the steering assembly22can be temporarily pivoted slightly leftwardly, as illustrated inFIG. 4, such that the direction of the front wheel18(e.g., centerline A) is angled (e.g., by an angle θ) from a substantially straight forward direction of travel (e.g., centerline B) of the motorcycle10. This leftward pivoting of the steering assembly22can cause the motorcycle10to lean rightwardly which can initiate turning of the motorcycle10in a rightward direction. Conversely, the motorcycle10can be countersteered into a left turn by temporarily pivoting the steering assembly22slightly rightwardly to cause the motorcycle10to lean leftwardly.

The controller40can be configured to operate the flywheel assembly12in order to impart a roll moment on the motorcycle10that facilitates effective countersteering of the motorcycle10. For example, when countersteering is initiated for a right turn (e.g., when the steering assembly22is pivoted leftwardly, as illustrated inFIG. 4), the controller40can cause rotation of the inertial mass32of the flywheel assembly12in a counterclockwise direction (e.g., as when viewing the flywheel assembly12from the front of the motorcycle10). Counterclockwise rotation of the inertial mass32can impart a counterclockwise roll moment on the motorcycle10that can accordingly influence the motorcycle10into a rightward lean. As illustrated inFIG. 1, a contact patch P between the front wheel18and a roadway can be located rearwardly of the point at which the steering axis A1intersects the roadway. Accordingly, when the motorcycle begins to lean rightwardly, the steering assembly22can automatically pivot further leftwardly which can lean the motorcycle10further rightwardly. When the motorcycle10has completed the rightward turn, (e.g., when the steering assembly22begins to be pivoted rightwardly to return the motorcycle10into an upright position), the controller40can reverse rotation of the inertial mass32into a clockwise direction which can impart a clockwise roll moment on the motorcycle10that influences the motorcycle10into an upward position (e.g., away from the rightward lean). The steering assembly22can automatically pivot further rightwardly which can lean the motorcycle10further into the upright position.

Conversely, when countersteering is initiated for a left turn (e.g., when the steering assembly22is pivoted rightwardly), the controller40can rotate the inertial mass32of the flywheel assembly12in a clockwise direction. Clockwise rotation of the inertial mass32can impart a clockwise roll moment on the motorcycle10that can influence the motorcycle10into a leftward lean. Accordingly, the steering assembly22can automatically pivot further rightwardly which causes the motorcycle10to lean further leftwardly. When the motorcycle10has completed the leftward turn, (e.g., when the steering assembly22begins to pivot leftwardly to return the motorcycle10into an upright position), the controller40can rotate the inertial mass32of the flywheel assembly12in a counterclockwise direction which can impart a counterclockwise roll moment on the motorcycle10that influences the motorcycle10into an upward position (e.g., away from the leftward lean). The steering assembly22can automatically pivot further leftwardly which can lean the motorcycle10further into the upright position. Operation of the flywheel assembly12in this manner can accordingly result in improved steering performance of the motorcycle10and improved steering response for an operator which can facilitate more effective operation of the motorcycle10through a turn. It will be appreciated that the flywheel assembly12can effectively provide electronic power steering assist for the motorcycle10.

It will be appreciated that the controller40can tailor the angular velocity of the inertial mass32to exert a roll moment that is appropriate for effective leaning of the motorcycle10and pivoting of the steering assembly22during countersteering. In one embodiment, the controller40can vary the angular velocity of the inertial mass32according to the speed of the motorcycle10and the severity of a turn. For example, the controller40can rotate the inertial mass32more slowly when the motorcycle10is navigating a gradual turn at a slow speed than when the motorcycle10is navigating a sharp turn at faster speeds. In one embodiment, the controller40can determine the severity of a turn according to the lean angle sensor44. In another embodiment, the path of turns for the motorcycle10can be predetermined such as when the motorcycle10is operated on a racetrack. In such an embodiment, the controller40can be loaded with predefined control directives for the inertial mass32that correspond to the path of the turns for motorcycle10. In another embodiment, the path of turns for the motorcycle10can be unspecified. In such an embodiment, the controller40can be configured to predict the path of turns for the motorcycle10such as with a global position system or other suitable predictive means. It will be appreciated that the controller40can additionally or alternatively determine the severity of a turn with any of a variety of suitable methods.

It will also be appreciated that the controller40can be configured to inhibit rotation of the inertial mass32when certain operating conditions might not permit effective countersteering of the motorcycle10. For example, pivoting of the steering assembly22during operation of the motorcycle10below a threshold speed (e.g., 15 M.P.H.) will typically turn the motorcycle10in the direction of the steering assembly22(e.g., no countersteer). Therefore, the controller40can be configured to inhibit rotation of the inertial mass32during operation of the motorcycle10below the threshold speed. In another example, during navigation of a turn, excessive pivoting of the steering assembly22or excessive leaning of the motorcycle10can result in the motorcycle10becoming unstable and possibly overturning. The controller40can therefore be configured to inhibit rotation of the inertial mass32during excessive pivoting of the steering assembly22(e.g., as detected by the steering assembly sensor42and transmitted to the controller40) or excessive leaning of the motorcycle10(e.g., as detected by the lean angle sensor44and transmitted to the controller40). In yet another example, the controller40can be configured to inhibit rotation of the inertial mass32when the motorcycle10is travelling in a substantially straight-forward direction (e.g., along centerline B illustrated inFIG. 4).

In one embodiment, the flywheel assembly12can be powered from the motorcycle's electrical system. During operation of the flywheel assembly12, an onboard battery of the motorcycle10can be charged and discharged in order to vary the rotation of the inertial mass32. Such operation of the flywheel assembly12using the motorcycle's onboard battery can overburden the onboard battery which can reduce the useful life of the onboard battery and can affect the overall performance of the motorcycle's electrical system. Thus, in an alternative embodiment, the flywheel assembly12can be coupled with a dedicated energy storage device (not shown). The dedicated energy storage device can be configured to exchange electrical energy with the flywheel assembly12. For example, to increase the angular velocity of the inertial mass32, electrical energy can be discharged from the dedicated energy storage device and provided to the flywheel assembly12. To decrease the angular velocity of the inertial mass32, electrical energy can be discharged from the flywheel assembly12and provided to charge the dedicated energy storage device. It will be appreciated that transferring energy between the flywheel assembly12and the dedicated energy storage device can reduce the electrical burden placed on the motorcycle's electrical system, thereby improving the longevity of the onboard battery and the overall performance of the motorcycle's electrical system.

It will be appreciated that the dedicated energy storage device can comprise any of a variety of suitable power sources such as, for example, a battery, a capacitor, a fuel cell, a hydraulic or pneumatic pressure source, or another mechanical energy storage device. The type of energy storage device can be selected based upon size, weight, energy storage capacity, efficiency, and other factors. In one embodiment, the dedicated energy storage device can include a flywheel battery. In such an embodiment, the positioning of the dedicated energy storage device upon a vehicle, such as a motorcycle, can be selected such that its gyroscopic effects do not adversely affect, or perhaps even positively affect, handling and other performance characteristics of the vehicle.

It will be appreciated that multiple rotatable inertial masses similar to rotatable inertial mass32can be implemented co-axially to provide redundancy of operation. When multiple rotating inertial masses act on a system, the sum of all of the individual roll moments produce a resultant roll moment on the entire system. Therefore, when multiple rotating masses of appreciable inertia are included in an embodiment, the controller can be configured to operate on each mass to produce the desired resultant moments.

In one embodiment, as illustrated inFIG. 1, the motorcycle10can include an electronic steering damper48. The electronic steering damper48can be in communication with the controller40, as illustrated inFIG. 3. The electronic steering damper48can be coupled with the steering assembly22and the frame16of the motorcycle10. The electronic steering damper48can be configured to restrict steering of the steering assembly22when operating conditions of the motorcycle10are not suitable for rapid turning of the motorcycle10. The controller40can operate the electronic steering damper48in conjunction with the flywheel assembly12. If the flywheel assembly12is operated during countersteering of the motorcycle10, the controller40can actuate the electronic steering damper48to resist pivoting of the steering assembly22. U.S. Patent Application Publication No. 2009/0198411 A1 is hereby incorporated herein by reference in its entirety, and discloses an electronic steering damper system for a vehicle.

Since the flywheel assembly12can be configured as a flywheel battery, as described above, it will be appreciated that in some embodiments the flywheel assembly12can be configured to provide supplemental electrical energy storage for the motorcycle10. For example, in one embodiment, the flywheel assembly12can be a backup energy storage source for the motorcycle's onboard battery. In such an embodiment, the flywheel assembly12can be fully charged (e.g., from the onboard battery) prior to shutting down the motorcycle10. If the onboard battery is discharged during shutdown (e.g., by leaving a headlamp on), the flywheel assembly12can provide the electrical energy necessary to start the motorcycle10in lieu of the onboard battery.

The foregoing description of embodiments and examples has been presented for purposes of illustration and description. It is not intended to be exhaustive or limiting to the forms described. Numerous modifications are possible in light of the above teachings. Some of those modifications have been discussed, and others will be understood by those skilled in the art. The embodiments were chosen and described in order to best illustrate principles of various embodiments as are suited to particular uses contemplated. The scope is, of course, not limited to the examples set forth herein, but can be employed in any number of applications and equivalent devices by those of ordinary skill in the art.