Modular Payload Boxes and Autonomous Water Vehicle Configured to Accept Same

Abstract

A modular payload system for an autonomous water vehicle includes a hull formed with a recessed portion that extends longitudinally over a region where a transverse cross section of a lower portion of the recess is constant along the region. A plurality of payload boxes are sized to fit in the recess and be distributed along the longitudinal axis. A transverse cross section of a lower portion of each payload box is configured complementarily with the lower portion of the recess. The payload boxes can be sized so that one payload box has a longitudinal dimension that is an integral multiple of the longitudinal dimension of the second payload box. The payload boxes can have complementarily positioned external electrical connectors to allow a jumper cable to serially connect the payload boxes.

Description

BACKGROUND OF THE INVENTION

This invention relates to payload boxes for autonomous water vehicles. In the exemplary embodiment, the payload boxes are deployed in an autonomous wave-powered vehicles (“WPV”), which is a device that is subject to waves in the water, and that in some cases utilizes the power of waves in water for propulsion.

As a wave travels along the surface of water, it produces vertical motion, but no net horizontal motion, of water. The amplitude of the vertical motion decreases with depth; at a depth of about half the wavelength, there is little vertical motion. The speed of currents induced by wind also decreases sharply with depth. A number of proposals have been made to utilize wave power to do useful work. Reference may be made, for example, to U.S. Pat. Nos. 986,627, 1,315,267, 2,520,804, 3,312,186, 3,453,981, 3,508,516, 3,845,733, 3,872,819, 3,928,967, 4,332,571, 4,371,347, 4,389,843, 4,598,547, 4,684,350, 4,842,560, 4,968,273, 5,084,630, 5,577,942, 6,099,368 and 6,561,856, U.S. Publication Nos. 2003/0220027 and 2004/0102107, and International Publication Nos. WO 1987/04401 and WO 1994/10029. The entire disclosure of each of those patents and publications is incorporated herein by reference for all purposes.

Many of the known WPVs comprise (1) a float, (2) a swimmer (referred to also as a sub or a glider, and (3) a tether (referred to also as an umbilical) connecting the float and the sub. The float, sub, and umbilical are such that when the vehicle is in still water, (i) the float is on or near the surface of the water, (ii) the sub is submerged below the float, and (iii) the umbilical is under tension. The sub comprises a fin or other wave-actuated component which, when the device is in wave-bearing water, interacts with the water to generate forces that can be used for a useful purpose, for example to move the sub in a direction having a horizontal component (hereinafter referred to simply as “horizontally” or “in a horizontal direction”). The terms “wing” and “fin” are used interchangeably in the art and in this application.

It is desirable to position sensors and equipment in the ocean or lakes for long periods of time without using fuel or relying on anchor lines which can be very large and difficult to maintain. In recent years, the WPVs developed by Liquid Robotics, Inc. and marketed under the registered trademark Wave Glider®, have demonstrated outstanding value, particularly because of their ability to operate autonomously. It is noted that Wave Glider® WPVs are often referred to as Wave Gliders as a shorthand terminology.

SUMMARY OF THE INVENTION

Embodiments provide an adaptable modular payload box system, which makes it easier to configure and reconfigure WPVs (or other autonomous water vehicles) for a wide variety of configurations. As these vehicles are more widely deployed, customers often wish to customize the vehicles for their own purposes.

In an aspect of the invention, a modular payload system for an autonomous water vehicle comprises a hull and a plurality of payload boxes. The hull has a longitudinal axis, and is formed with a recessed portion that extends longitudinally over a region where a transverse cross section of a lower portion of the recess is constant along the region. The payload boxes are sized to fit in the recess and be distributed along the longitudinal axis. A transverse cross section of a lower portion of each payload box is configured complementarily with the lower portion of the recess. This can provide ease of configuration and reconfiguration.

In an embodiment of the present invention: the plurality of payload boxes includes first and second payload boxes; and the first payload box has a longitudinal dimension that is an integral multiple of a longitudinal dimension of the second payload box.

In an embodiment of the present invention, at least first and second payload boxes have complementarily positioned external electrical connectors to allow a jumper cable to serially connect the payload boxes. This can provide further flexibility

A further understanding of the nature and advantages of the present invention may be realized by reference to the remaining portions of the specification and the drawings, which are intended to be exemplary and not limiting.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a pictorial view showing the operation of a prior art wave-powered vehicle (“WPV”) in still water (fins/wings in neutral position), when a wave lifts the float (up-stroke), and when the WPD sinks into the wave trough (down-stroke);

FIGS. 2A and 2B are exploded views of a current embodiment of a WPV hull and modular payload boxes;

FIGS. 2C and 2D show additional views of a WPV hull and modular payload boxes;

FIG. 3A is a perspective view from the front of a modular payload box configured to hold the WPV's command and control unit (“CCU”) electronics;

FIG. 3B is front view of the CCU payload box shown in FIG. 3A;

FIGS. 3C and 3D are perspective views of the top and bottom halves of the CCU payload box shown in FIG. 3A;

FIGS. 3E and 3F are front and side views of the bottom half of the CCU payload box shown in FIG. 3A;

FIG. 4A shows a modular payload box configured to hold a battery pack;

FIGS. 4B and 4C are perspective views of the top and bottom halves of the battery payload box shown in FIG. 4A;

FIGS. 4D and 4E are front and side views of the bottom half of the battery payload box shown in FIG. 4A;

FIG. 5 is an upper perspective view of a male electrical connector, with pins or prongs configured to operably and reversibly engage or couple with a corresponding female connector, thereby operably connecting a payload box to another payload box, control center, or electrical support structure;

FIG. 6A is an upper perspective view of a male electrical connector of this invention, with optional cladding partway down the pins to help form a water-tight seal with a corresponding female connector;

FIG. 6B is a side orthogonal view of a male electrical connector;

FIG. 7 is an upper perspective view of a female electrical connector of this invention, with socket holes configured to operably and reversibly couple with a corresponding male connector;

FIGS. 8A and 8B are perspective views showing where a male connector is paired with a female connector with corresponding pin and socket hole arrangements on each; and

FIG. 9 is a perspective view showing where a male connector is operably engaged or coupled with a female connector by inserting the pins of the male connector into the corresponding socket holes of the female connector.

DESCRIPTION OF SPECIFIC EMBODIMENTS

Autonomous Water Vehicle Overview

FIG. 1 is a side view showing three images of a wave-powered water vehicle 10. The vehicle comprises a “float” 15 resting on the water surface, and a “sub” or “glider” 20 hanging below, suspended by a tether 25. The float 15 comprises a displacement hull 30 and a fixed keel fin 35. The sub comprises a rudder 40 for steering and “wings” or “fins” 45 connected to a central beam of a rack 50 so as to permit rotation of the wings around a transverse axis within a constrained range, and provide propulsion. Vehicle 10 carries a number of solar panels 55 on its upper surface to provide power to the vessel, as will be described in detail below.

In still water (shown in the leftmost panel), the submerged sub 20 hangs level by way of tether 25 directly below float 15. As a wave lifts float 15 (middle panel), an upwards force is generated on the tether 25, pulling sub 20 upwards through the water. This causes wings 45 of the sub to rotate about a transverse axis where the wings are connected to rack 50, and assume a downwards sloping position. As the water is forced downward through the sub, the downwards sloping wings generate forward thrust, and the sub pulls the float forward. After the wave crests (rightmost panel), the float descends into a trough. The sub also sinks, since it is heavier than water, keeping tension on the tether. The wings rotate about the transverse axis the other way, assuming an upwards sloping position. As the water is forced upwards through the sub, the upwards sloping wings generate forward thrust, and the sub again pulls the float forwards.

Thus, the sub generates forward thrust both when it is ascending and when it is descending, resulting in forward motion of the entire vehicle.

Adaptable Modular Power System (“AMPS”) Overview

An autonomous water vehicle is capable of carrying instrumentation for long-term observation of various metrics in the world's oceans. Useful oceanographic instruments typically require electrical power for their operation. Because of the long-term duration of missions and the platform's finite size, the system-wide power resources are limited. Therefore, efficient methods to collect and distribute electrical energy are needed. Further, sensor power requirements can vary wildly and the power system should adapt to these needs.

In short, AMPS provides a set of electronic modules that interface power sources, energy storage devices, and loads (power consuming devices) to a 3-wire power distribution bus (often referred to simply as the “power bus”) so that power can be efficiently collected, stored, and distributed. Within a given system, the AMPS modules can be, and often are, divided into groups referred to as power domains. This division can parallel a functional division of system components on the water vehicle. For example, the deployment of functional elements in separate payload boxes can lead to a corresponding mapping of the AMPS modules for those functional elements into separate power domains.

Waterproof connectors are used to interconnect different instrumentation clusters. These clusters are housed in separate drybox enclosures (sometimes referred to as payload boxes) to minimize the effects of a possible leak. These waterproof connectors are expensive, so the number of this type of connection should be minimized. Finally, it is desirable that sensors can be added to the platform easily. Further, sensors and actuators can reside on the sub, and conductors housed in the umbilical provide electrical connections between the float and the sub.

Payload boxes can contain the vessel's command and control unit (“CCU”), customer-supplied electronics, and auxiliary power packs (e.g., battery packs). As will be described below, these payload boxes can be modular so as to facilitate rapid configuration and reconfiguration (e.g., upgrades) of the vessel electronics. While AMPS provides a modular power management system, this modularity of the power system is not required for the modular payload box system provided by embodiments of the present invention.

Modular Payload Box System

Embodiments of the present invention provide a modular payload box system that makes effective use of the vehicle's limited payload space and allows payload boxes to be easily added to the vehicle.

FIGS. 2A and 2B are exploded views of a current embodiment of a WPV hull 30 and modular payload boxes 60 and further show how payload boxes can be fabricated in lengths (along the hull's axis) that are integral multiples of a modular payload unit (“MPU”). FIG. 2A shows how solar panels 55 would be placed over the payload boxes. FIG. 2B shows some additional construction detail. While dimensions are not critical, it is noted that the hull in this embodiment is about 114 inches (2.9 meters) in length and provides about 3.3 cubic feet (93 liters) of payload space. The basic MPU is about 1 foot. FIGS. 2C and 2D show additional views of a WPV hull and modular payload boxes.

FIG. 3A is a perspective view from the front of a modular payload box 65 configured to hold the WPV's command and control unit (“CCU”) electronics, and FIG. 3B is front view of the CCU payload box shown in FIG. 3A. The CCU payload box extends 3 MPU along the hull axis. Also shown are cables for carrying signals to and from the CCU electronics, and the base for one of several antennas that are typically deployed on an autonomous water vehicle. The front view shows the transverse cross section of the lower portion of the modular payload box. FIGS. 3C and 3D are perspective views of the top and bottom halves of the CCU payload box shown in FIG. 3A. FIGS. 3E and 3F are front and side views of the bottom half of the CCU payload box shown in FIG. 3A.

FIG. 4A shows a modular payload box 70 configured to hold a battery pack, and FIGS. 4B and 4C are perspective views of the top and bottom halves of the battery payload box shown in FIG. 4A. The battery payload box extends 1 MPU along the hull axis. FIGS. 4D and 4E are front and side views of the bottom half of the modular payload box shown in FIG. 4A. As can be seen, the lower portion of battery payload box 70 has substantially the same transverse cross section as that of the CCU payload box. Suitable materials for the payload boxes include molded reinforced plastic resins. A current choice is 30% glassed filled plastic resin sold under the trade name Noryl by SABIC Innovative Plastics Holding BV. Alternative materials are aluminum, and ABS.

Dedicated Connector

Described below is a connector system that allows modular payload boxes to interconnect with other modules, with control systems in the vessel, and optionally with other equipment that integrates with one or more AMPS domains when the vessel is on shore or connected to other vessels. The system comprises a male connector and a female connector configured to make electrical contact with each other at a plurality of locations to provide for exchange or relay of power, signaling, control, and/or data exchange in any combination.

In a specific implementation, a common interconnect cable between power domains (located in modular payload boxes) includes, in addition to the three AMPS power bus conductors:

four conductors for high speed signaling such as fast Ethernet;

two conductors for CAN signaling to control the power domains as discussed below;

two conductors for other purposes such as broadcast communications, serial communications, and the like; and

one conductor for a shield.

This cabling and connector arrangement can be used, even if certain conductors are not required, since the benefits of a universal cable and the possibility of future expansion offset the fact that in some instances, one or more of the conductors will not be used by connected elements.

FIGS. 5 to 9 show possible form features of connectors that are used to connect various payload boxes so that the electronics in the payload boxes can functionally interact. Fundamentally, any operable pin shape and arrangement can be used, so long as the pins or prongs in the male connector align with the socket holes of the female connector in such a way that the pins can be reversibly inserted into the socket holes. The illustrative arrangement or design choice shown in these figures has the pins on a male connector and corresponding socket holes on a female connector that are round in cross-section.

FIG. 5 is a perspective view showing a male connector at the end of a cable that is used for connecting various payload boxes. As can be seen, the pins (and corresponding socket holes) are arranged in two concentric circles on the respective connectors, and three of the pins are larger than the other nine. These are the three AMPS power bus conductors. The smaller pins are for the signaling (four conductors for fast Ethernet, two conductors for CAN signaling, and two conductors for serial communications), plus one conductor for the shield.

The housing is made of a waterproof non-conductive material, such as a rubber or thermoplastic, and may be manufactured in any suitable shape. Here, the housing is shown having a substantially cylindrical main portion, a tapered section, and a bulb that can be grasped and pulled by the user and thereby used to help detach a male plug inserted into a female plug.

FIG. 6A shows another exemplary male electrical connector male electrical connector where the pins or prongs have a cladding part way along their length from the housing. In this configuration, the cladding is made of a non-conductive rubber or thermoplastic material, and helps create a tight waterproof seal with the sides of socket holes on a female connector when inserted therein. FIG. 6B is a longitudinal view of the same male connector.

FIG. 7 shows a female electrical connector of this invention, with socket holes arranged and configured in a housing with a receding cable such that the socket holes to operably and reversibly engage a corresponding pin on a male connector. The socket holes are arranged in a pattern that is a mirror image to the pins of a reversibly inserted male connector. The pins and the socket holes on the male and female connector, respectively, are each sized and shaped to engage with the corresponding socket hole or pin on the opposing female and male connector.

The pins and socket holes can also be sized and shaped so as to help form a waterproof seal around each pin—for example, with the socket holes having a diameter that is slightly smaller than the widest diameter of the pins. Alternatively or in addition, the female housing and/or the male housing can be equipped with a collar (not shown) that reversibly engages the housing or collar on the opposing male or female connector, such that when the two connectors are engaged, the collar(s) form a waterproof seal that surrounds the front planar surfaces that oppose each other when the female and male connectors are operably engaged.

FIGS. 8A, 8B, and 9 show a male and female connector in combination, where a male connector is paired with a female connector with arrangements of pin and socket holes that correspond so that the pins of the male connector can be fully pushed into the socket holes of the female connector, thereby electrically joining the respective power or signal lines. In FIGS. 8A and 8B, corresponding male and female connectors are shown separate and aligned with each other. In FIG. 9, the connector pair is shown with the pins of the male connector engaging the socket holes of the female connector such that the front planar surface of the housing of the male and female connectors are adjacent.

CONCLUSION

In conclusion, it can be seen that embodiments of the invention provide a flexible and scalable payload box system.

While the above is a complete description of specific embodiments of the invention, the above description should not be taken as limiting the scope of the invention as defined by the claims.

Claims

1. A modular payload system for an autonomous water vehicle comprising: a hull having a longitudinal axis, the hull being formed with a recessed portion that extends longitudinally over a region where a transverse cross section of a lower portion of the recess is constant along the region;a plurality of payload boxes sized to fit in the recess and be distributed along the longitudinal axis, wherein a transverse cross section of a lower portion of each payload box is configured complementarily with the lower portion of the recess.

2. The modular payload system of claim 1 wherein: the plurality of payload boxes includes first and second payload boxes; andthe first payload box has a longitudinal dimension that is an integral multiple of a longitudinal dimension of the second payload box.

3. The modular payload system of claim 1 wherein at least first and second payload boxes have complementarily positioned external electrical connectors to allow a jumper cable to serially connect the payload boxes.