The present invention relates to the field of autonomous vehicles and, in particular, to a brake or brake system for a submersible autonomous vehicle.
Autonomous vehicles are being introduced into an ever increasing number of facets of daily life in order to automate various tasks, such as cleaning a pool, cleaning an indoor space, and maintaining a lawn. Many of these autonomous vehicles and, in particular, submersible autonomous vehicles, such as pool cleaners, use jet or fluid propulsion (e.g., an impeller and/or propeller) to drive or propel the autonomous vehicle along a surface (e.g., the surface of a pool).
Since pool cleaners often require a pump or suction system to clean a pool, it is often economically efficient (and efficient in terms of space and size) to utilize the pump system for both cleaning and propulsion (e.g., as opposed to including a dedicated/second drive system). As an example, U.S. Pat. No. 8,273,183, which is incorporated by reference herein, discloses an autonomous pool cleaner with a water jet propulsion system that draws in water for both cleaning and propulsion. In order to utilize the drawn-in water to propel or move the pool cleaner along a surface, the pump system discharges the drawn-in water, as a pressurized stream, at an acute angle with respect to the surface. In the particular example of U.S. Pat. No. 8,273,183, the pressurized stream may be discharged in different directions to control steering of the submersible autonomous vehicle.
However, even as the number and configuration of discharge directions is updated, a jet or fluid propulsion drive system may still only offer limited steering control. For example, a submersible autonomous vehicle with a jet propulsion system may have a limited turning radius and may not be able to turn or pivot about a specific point on a surface. In some instances, a second drive system can be added to the autonomous pool cleaner; however, this may be expensive and inefficient.
In view of at least the aforementioned issues, a brake module or system that is driven or actuated by an existing fluid propulsion drive system while also providing increased steering control is desirable.
The present invention relates to a brake system or module for a submersible autonomous vehicle. The brake module may include a switch (for an electrical embodiment of the brake module) or lever (for a mechanical embodiment of the brake module) that is configured to selectively engage a wheel included on the submersible autonomous vehicle. In at least some embodiments, the lever will be biased to engage the wheel, thereby preventing the wheel from rotating until the lever is actuated. Then, when the lever is actuated, the lever will disengage from the wheel, allowing the wheel to rotate freely. The biasing of the lever may cause the lever to re-engage the wheel when the lever is no longer actuated.
In at least some embodiments, the switch or lever is actuated when the internal pump system of the submersible autonomous vehicle is run at or above a certain speed or power threshold. Consequently, at higher pump speeds and/or pump power (directly related to the voltage supplied to the pump), where the submersible autonomous pool cleaner is presumably propelled in a straight line, a wheel including the brake module will be free to rotate and the pool cleaner may be propelled, unimpeded, by the pump system (since the switch or lever is actuated to a position that disengages the brake module from the wheel). Then, when the pump system is run below the speed or power threshold, the brake module may re-engage the wheel. When the brake module is engaged with the wheel, the wheel is fixed (stopped from rotating) and the submersible autonomous pool cleaner may be able to turn or pivot about the fixed wheel. Consequently, the brake module may provide the submersible autonomous pool cleaner with fine-tuned steering control, as well as tight turning and maneuvering.
The present invention avoids problems posed by known submersible autonomous vehicles with jet or fluid propulsion (e.g., turning, steering, and size/space efficiency issues) by providing a brake module that allows for fine-tuned steering movements without adding a secondary drive system or other expensive and complicated steering components or assemblies. In fact, the brake module may, in at least some embodiments, be utilized with pre-existing jet propulsion systems with only minor modifications. Consequently, the brake module presented herein provides a cost-efficient steering improvement for jet or fluid propelled submersible autonomous vehicles, such as submersible autonomous pool cleaners. Note however, that the brake module presented herein could also be selectively applied to motor driven (as opposed to fluid driven) submersible autonomous vehicles.
To complete the description and in order to provide for a better understanding of the present invention, a set of drawings is provided. The drawings form an integral part of the description and illustrate an embodiment of the present invention, which should not be interpreted as restricting the scope of the invention, but just as an example of how the invention can be carried out. The drawings comprise the following figures:
The following description is not to be taken in a limiting sense but is given solely for the purpose of describing the broad principles of the invention. Embodiments of the invention will be described by way of example, with reference to the above-mentioned drawings showing elements and results according to the present invention.
Generally, the brake module presented herein includes a braking mechanism configured to allow or prevent a wheel of a submersible autonomous vehicle from rotating. In at least some embodiments, a piston diaphragm or bladder acts similar to a bellows to actuate or control the braking mechanism. More specifically, the piston diaphragm/bellows/bladder distends when water is pumped, by a fluid or jet propulsion system of a submersible autonomous robot, through the autonomous robot at or above a predetermined parameter threshold (e.g., a rate of speed or pressure threshold). In at least some embodiments, distention of the piston diaphragm/bellows/bladder causes the braking mechanism to move out of engagement (e.g., out of contact) with a wheel of the submersible autonomous vehicle, thereby freeing the wheel to rotate. However, in other embodiments, distention of the piston diaphragm/bellows/bladder causes the braking mechanism to move into engagement (e.g., into contact) with a wheel of the submersible autonomous vehicle, thereby preventing the wheel from rotating.
In other words, generally, the brake module presented herein provides a fluid-actuated switch or lock configured to restrict or lock (or, alternatively, free or unlock) the rotation of a wheel of a submersible autonomous vehicle during operation of the autonomous vehicle (where the phrase “fluid-actuated” means that the switch is actuated at least because of movement of fluid through the submersible autonomous vehicle). However, the braking mechanism need not be directly actuated by a fluid-based bladder/piston diaphragm and may also be generally based on other elements/parameters associated with pumping fluid through the submersible autonomous vehicle. For example, in some embodiments, the braking mechanism may be actuated by electromagnetic elements configured to move into or out of engagement with a wheel of the submersible autonomous vehicle based on the voltage supplied to a pump system of the submersible autonomous vehicle. Thus, in at least these embodiments, the braking mechanism is fluid-actuated because the braking mechanism is actuated based on voltage drawn into a pump system configured to pump fluid through the submersible autonomous vehicle.
Advantageously, the fluid-actuated braking mechanism can be actuated during operation of a submersible autonomous vehicle to provide fine-tuned steering control of the submersible autonomous vehicle. For example, the fluid-actuated braking mechanism can momentarily rotationally lock a wheel of the submersible autonomous vehicle to allow the submersible autonomous vehicle to pivot around a locked wheel. This allows the autonomous vehicle to make approximately 90 degree turns, hair-pin turns, and other such maneuvers that a fluid propulsion system generally does not typically allow (due to the typically circuitous navigation provided by fluid propulsion). Moreover, the fluid-actuated braking mechanism can be actuated for a precise amount of time (via a control system of the submersible autonomous vehicle) and, thus, a wheel can be locked for a precise amount of time to cause the autonomous vehicle to execute a specific turn (e.g., 30 degrees). This allows for specific and/or specialized navigational programming.
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The lever or braking mechanism 170 includes a first segment 172 and a second segment 182 that extend from opposite sides of a pivot point or fulcrum 188. The braking mechanism 170 also includes a resilient or biasing member 190 that extends from or approximately from the fulcrum 188. In this particular embodiment, the distal end of the first segment 172 (e.g., the end of the segment 172 that is a distance from the fulcrum 188) includes teeth 174 separated by a cavity 176 formed therebetween. As is shown and described below in connection with
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In at least some embodiments, the biasing member 190 of the braking mechanism 170 is resilient, insofar as the resiliency of the biasing member urges the biasing member 190 back to a natural or resting position P5. In its natural or resting position P5, the biasing member 190 rests against a biasing support 22 (which may be included in the brake module 100 or the housing 20 of the submersible autonomous vehicle 10 as shown, for example, in
Additionally, the piston diaphragm 160 may be biased to position P1. In some embodiments, the piston diaphragm 160 may be configured to be disposed substantially within the piston base 102 (e.g., be in position P1) under normal pressure and volume conditions (e.g., when the pressure and volume are beneath certain thresholds), essentially biasing itself to position P1. Additionally or alternatively, the braking mechanism 170 may retain, push, or urge the piston diaphragm 160 in or to position P1, such that biasing member 190 essentially biases the braking mechanism 170 to position P3 and the piston diaphragm 160 to position P1.
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The brake mechanism 100 is in operatively coupled to the pump mechanism 14 and/or a portion of the fluid propulsion system 11 that transfers the pressurized streams from the pump mechanism 14 to vent 16A and vent 16B. For example, in the embodiment depicted in
In some embodiments, the tube 18 is connected directly to the pump mechanism 14 and/or a section of the fluid propulsion system 11, but in other embodiments, the tube 18 is connected via a connection element 19. For example, the connection element 19 may comprise a pump or impeller coupled to the pump mechanism 14 and/or a power line providing power to the pump mechanism and/or a seal connecting the tube 18 to an exhaust or other such element that can deliver pressure generated by the pump mechanism 14 to the brake module 100. Additionally or alternatively, the connection element 19 may comprise an input circuit of an electromagnetic linkage coupled to the brake module 100 (where the tube 18 would not be required).
In embodiments where the connection element 19 comprises a pump or impeller, the pump or impeller may be mechanically and/or electrically linked with the pump mechanism 14 and/or the power delivered to the pump mechanism 14. Thus, the pump or impeller may generate pressure proportionally to the speed/power/pressure of the pump mechanism 14. For example, the pump or impeller may take power off the shaft of a motor driving the pump mechanism 14 (such as via a power-take-off unit (PTO) or gearbox) and, thus, be run at a speed that is proportional to the speed of the pump mechanism 14 (e.g., some ratio). The pump or impeller may be coaxial to the motor of the pump mechanism 14, connected thereto via a gearbox (and, thus, run proportionally to the motor speed), or connected in any other manner. Regardless of how the pump or impeller is connected to the jet propulsion system 11 and the tube 18, running the pump or impeller may generate pressure in tube 18 causing a flow down tube 18 as illustrated by flow F3. Flow F3 may increase the volume and/or pressure of fluid in the piston diaphragm 160 of the brake module 100, thereby actuating the braking mechanism 170, as discussed above in connection with
Alternatively, in some embodiments, the tube 18 may be in direct or indirect fluid communication with the fluid propulsion system 11 (e.g., via a venturi created by connection 19) and, thus a pressurized stream of fluid generated by the pump mechanism 14 may propel fluid down tube 18, as illustrated by flow F3. As mentioned, flow F3 may increase the volume of fluid in the piston diaphragm 160 of the brake module 100. In yet other embodiments, the flow F3 into tube 18 from the fluid of the fluid propulsion system 11 may be selectively regulated (e.g., by an optional valve 19). In this configuration, increased output from the pump mechanism 14 may selectively increase the flow into the piston diaphragm 160 of the brake module 100 (based on the position of valve 19).
Regardless of how the brake module 100 is in communication with the fluid propulsion system 11, running the fluid propulsion system 11 above certain parameter thresholds will actuate the braking mechanism 170 (e.g., by mechanically or electromagnetically rotating a lever or by actuating an electromagnetic pin or by actuating a solenoid) of the brake module 100, thereby freeing an associated wheel assembly 200 to rotate.
More specifically, in the depicted embodiment, when voltage is provided to the pump mechanism 14 above a certain power threshold, the motor of the pump mechanism 14 may increase the pressure and/or volume directed towards the piston diaphragm 160 of the brake module 100 (e.g., by increasing the speed of a connected pump or impeller 19, thereby increasing pressure directed down tube 18), causing the piston diaphragm 160 to distend and move to a position beyond the expansion threshold (e.g., position P2). This expansion, in turn, actuates the braking mechanism 170 to disengage from the wheel assembly 200 (e.g., the braking mechanism 170 moves to position P4).
Then, as the voltage delivered to the pump mechanism 14 of the fluid propulsion system 11, or components thereof, decreases, these components will begin to run below the parameter thresholds and the pressure being directed towards the piston diaphragm 160 begins to decrease (e.g., the pump or impeller 19 may shut-off when the power delivered to the pump mechanism 14 is below a power threshold and pressure may begin to disperse along the length of tube 18), causing the piston diaphragm 160 to begin to deflate (due, at least in part, to the biasing of piston diaphragm 160). This deflation causes the braking mechanism 170 to reengage the wheel assembly (e.g., the braking mechanism 170 moves to position P3). This restricts (i.e., begins or attempts to stop/lock) the wheel or locks the wheel in place and provides a pivot point for tight turns or other such maneuvers. In at least some embodiments, fluid flow F3 may reverse its direction as the piston diaphragm 160 deflates.
In different embodiments, the parameter thresholds can be determined or configured in order to allow for precise steering control in a particular environment. For example, a speed/voltage threshold may be determined based on performance of a particular robot in a particular pool. Once a speed/voltage threshold is set appropriately, the brake module 100 may be configured to disengage from the wheel 200 at pump motor speeds (e.g. the pump motor from the motor mechanism 14) associated with straight line movements and engage the wheel 200 at pump motor speeds associated with turning movements. Then, using this knowledge, the pump motor 14 may be programmed to drop to turning speeds for certain amount of times in order to turn a certain angle. For example, the pump motor may run below the speed threshold for approximately one second to effectuate a turn of approximately 30 degrees (e.g., one second below the speed threshold causes a one second pivot about the wheel associated with the brake module 100, which results in a 30 degree turn of the submersible autonomous vehicle).
To summarize, in one form, a brake module for autonomous vehicles is disclosed. The brake module includes a bladder in fluid communication with a fluid propulsion system of an autonomous vehicle (or some other source of control) and an engagement element configured to selectively engage a wheel of the autonomous vehicle. The engagement element prevents movement of the wheel when engaged with the wheel and is configured to disengage from the wheel when the fluid propulsion system (or other control system) is run at a setting that exceeds a disengagement threshold.
In another form, a submersible autonomous vehicle is disclosed, the submersible autonomous vehicle comprising: a fluid propulsion system; a wheel assembly; and a brake module that is operatively connected to the fluid propulsion system and configured to allow or restrict the wheel assembly from rotating when the fluid propulsion system operates with an operating parameter above a parameter threshold.
In yet another form, a fluid-actuated brake module for a submersible autonomous vehicle is provided herein, the fluid-actuated brake module comprising: a fluid-actuated actuator that is operatively coupleable to a fluid propulsion system of an autonomous vehicle; and a braking mechanism that selectively engages or disengages a wheel assembly included in the autonomous vehicle in response to an actuation of the fluid-actuated actuator, wherein engagement between the braking mechanism and the wheel assembly restricts the wheel assembly from rotating and disengagement between the braking mechanism and the wheel assembly allows the wheel assembly to rotate.
While the invention has been illustrated and described in detail and with reference to specific embodiments thereof, it is nevertheless not intended to be limited to the details shown, since it will be apparent that various modifications and structural changes may be made therein without departing from the scope of the inventions and within the scope and range of equivalents of the claims. In addition, various features from one of the embodiments may be incorporated into another of the embodiments. Accordingly, it is appropriate that the appended claims be construed broadly and in a manner consistent with the scope of the disclosure as set forth in the following claims.
It is also to be understood that the brake module described herein, or portions thereof may be fabricated from any suitable material or combination of materials, such as plastic, foamed plastic, wood, cardboard, pressed paper, metal, supple natural or synthetic materials including, but not limited to, cotton, elastomers, polyester, plastic, rubber, derivatives thereof, and combinations thereof. Suitable plastics may include high-density polyethylene (HDPE), low-density polyethylene (LDPE), polystyrene, acrylonitrile butadiene styrene (ABS), polycarbonate, polyethylene terephthalate (PET), polypropylene, ethylene-vinyl acetate (EVA), or the like. Suitable foamed plastics may include expanded or extruded polystyrene, expanded or extruded polypropylene, EVA foam, derivatives thereof, and combinations thereof.
Finally, it is intended that the present invention cover the modifications and variations of this invention that come within the scope of the appended claims and their equivalents. For example, it is to be understood that terms such as “left,” “right,” “top,” “bottom,” “front,” “rear,” “side,” “height,” “length,” “width,” “upper,” “lower,” “interior,” “exterior,” “inner,” “outer” and the like as may be used herein, merely describe points of reference and do not limit the present invention to any particular orientation or configuration. Further, the term “exemplary” is used herein to describe an example or illustration. Any embodiment described herein as exemplary is not to be construed as a preferred or advantageous embodiment, but rather as one example or illustration of a possible embodiment of the invention.
Similarly, when used herein, the term “comprises” and its derivations (such as “comprising”, etc.) should not be understood in an excluding sense, that is, these terms should not be interpreted as excluding the possibility that what is described and defined may include further elements, steps, etc. Meanwhile, when used herein, the term “approximately” and terms of its family (such as “approximate”, etc.) should be understood as indicating values very near to those which accompany the aforementioned term. That is to say, a deviation within reasonable limits from an exact value should be accepted, because a skilled person in the art will understand that such a deviation from the values indicated is inevitable due to measurement inaccuracies, etc. The same applies to the terms “about” and “around” and “substantially”.
This application claims priority to and the benefit of U.S. Provisional Patent Application No. 62/431,689, filed Dec. 8, 2016, and entitled “Brake Module for Submersible Autonomous Vehicles,” the disclosure of which is incorporated herein by reference in its entirety.
Number | Date | Country | |
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62431689 | Dec 2016 | US |