Patent Description:
As research grows, metabolic components to non-strictly metabolic diseases are being discovered. Research laboratories need a low-cost, high-throughput method to regulate an animal's metabolism.

Currently available technology is expensive and superfluous, making these options low-throughput for prospective interdisciplinary metabolic studies. Currently available automated food access methods for animals typically fall within three categories: metabolic, specially modified, or operant behavior cages.

Metabolic cages control numerous aspects of a single-housed animal's environment, including water, food, and exercise access, while simultaneously recording multiple data points. However, if automated food access is the only feature that is needed, then the metabolic cages are an expensive and superfluous alternative. This problem is compounded as the population size and duration of a study increases, requiring the use of more cages. Due to cost, animals (e.g. mice) are not typically raised in a metabolic cage, and thus, moving an animal from its home cage to a metabolic cage may induce anxiety and behavioral changes, risking the introduction of confounding variables. Metabolic cages are also bulky and usually not compatible with a vivarium's existing cage rack. Examples of metabolic cages include CLAMS from Columbus Instruments and the TSE Systems PhenoMaster.

Specially modified cages typically take an animal's current home cage and cut a hole in it to allow an external automated food access device. This prevents the need to transfer an animal to a different cage. However, modified cages expose the home cage to the outside environment, preventing recirculation of clean air into the home cage. This makes animals susceptible to potential airborne contagions, as well as researcher borne scents and confounding molecules within the vivarium. Additionally, since these cage modifications are external, a vivarium's existing cage rack would no longer be able to house the modified cage. Examples of specially modified cages are the Research Diet BioDAQ Gated and TSE Systems FeedTime.

Operant behavior cages can also provide automated food access but require conditioning the animals to perform a specific behavior before receiving a food reward, which introduces unnecessary confounding variables. These cages can be modified to instead dispense food during specific time intervals. However, the food is dispensed as reward pellets rather than standard chow and in pre-determined quantities, making it not an ideal solution when studies require unlimited food access during feeding times. Additionally, the animals have access to any excess food dispensed into the cage, defeating the purpose of having specific feeding time intervals. An example of an operant behavior cage includes the Noldus PhenoTyper.

<CIT> discloses automated feed dispensers for animal cages. An automatic dispenser is designed such that a feed container and a closure surface can be moved relative to one another, such that in a closed position, the closure surface covers the access opening and blocks access to the inside of the container, and in the open position, the inside of the container can be accessed. In one embodiment, a system of automatic food dispensers comprises a group of automatic dispensers coupled to respective cages, each automatic dispenser configured for communication by Radio frequency signals with a central control unit. The central control unit is programmed to automatically manage the plurality of automatic dispensers.

Consequently, there is room in the art for improvement.

An aspect of the invention is presented in the independent claim <NUM>. Further embodiments are presented in the dependent claims.

In a server controller side, an apparatus comprises at least one access control device, comprising: a controller configured to deliver access signals according to an access schedule based on data entered into the controller by an operator; and a movable barrier configured to be positioned in a home cage between a storage area and a living area and configured to be movable between an access position where there is unrestricted access to an item in the food storage area from the living area and a restricted position where the access is denied. The movable barrier is moved between the access position and the restricted position in response to the access signals. The movable barrier is configured to fit entirely within the home cage and a lid of the home cage without making any modifications to the home cage or the lid. In an embodiment, the movable barrier is configured to hang from a pre-existing food hopper configured for the home cage.

According to the invention, at least one food access control device comprises two access control devices. In a server access control device of the two access control devices the controller comprises a server controller. In a client access control device of the two access control devices the controller comprises a client controller in signal communication with the server controller. In the server controller the access schedule is based on the data entered into the server controller by the operator. In the client controller the access schedule is based on the data entered into the server controller.

The invention is explained in the following description in view of the drawings that show:.

The Inventors have developed a novel and innovative access control device capable of automatically controlling access to single-housed or group-housed animals based on an operator-designated schedule. The access control device can control access to food, or, in embodiments not forming part of the claimed invention, to water, to an object, to a region within a cage, and/or may immobilize (restrict access to) /release (permit access to) a device (e.g. exercise wheel). The embodiment disclosed herein controls access to food, but the disclosure is not limited to this embodiment.

Designed as an alternative to expensive metabolic home cages, a food access control device is used in the animal's home cage, reducing potential confounding variables. To avoid taking up additional space in the home cage, this food access control device may operate within or suspend from an empty food hopper and does not interfere with the existing home cage lid or rack. One food access control device is needed per home cage and any number of home cages can be set up using this low-cost, high-throughput system.

As can be seen in <FIG>, the food access control device <NUM> restricts and restores food access on a timer in an animal's home cage <NUM>. Each home cage <NUM> has its own food access control device <NUM>, which consists of one controller <NUM>, one positioning mechanism <NUM>, and one movable barrier <NUM>. In this embodiment, the movable barrier <NUM> is a barrier to a region within the home cage <NUM> in which the food is disposed. As noted above, the movable barrier <NUM> may alternatively be a barrier to water, to an object (e.g. exercise wheel), to a region within a cage, and/or may immobilize/release a device.

In an embodiment, the controller <NUM> is an open source controller capable of wireless local area networking using an Internet-of-Things platform. An example controller is a NodeMCU. The NodeMCU is a WiFi-capable microcontroller that can be programmed using C/C++ and is powered using a single micro USB cable. The NodeMCU is capable of controlling the positioning mechanism <NUM>. In an embodiment, the positioning mechanism <NUM> is a servomotor or a stepper motor, which is a small motor capable of moving the movable barrier <NUM> back and forth between a restricted position <NUM> and an access position <NUM>. In an embodiment, the servomotor/stepper motor rotates the movable barrier <NUM>. In an embodiment, the rotation is <NUM> degrees.

The food access control device <NUM> is configured to fit entirely within the home cage <NUM>. In an embodiment, the food access control device <NUM> fits between living area <NUM> and a food storage area <NUM>. In an embodiment, the food access control device <NUM> fits within or is suspended from a hopper <NUM> of the home cage <NUM>. In an embodiment, the food access control device <NUM> fits entirely within the home cage <NUM> and a lid when the home cage <NUM> and the lid form a seal configured to keep out unfiltered, environmental air.

When using only one server food access control device <NUM>, which is not according to the invention, the food access control device <NUM> is designated a server food access control device <NUM>. <FIG> shows the server food access control device <NUM>. The associated home cage <NUM> will be designated as the server home cage <NUM>. When using multiple food access control devices <NUM>, one food access control device <NUM> is a server food access control device <NUM> and subsequent/associated food access control devices <NUM> are designated client food access control devices <NUM>. <FIG> shows the client food access control device <NUM>. The associated home cages <NUM> will be designated as client home cages <NUM>.

As shown in <FIG>, the server food access control device <NUM> has an input device <NUM> through which the operator can input data into the controller <NUM> to be used for the schedule. In the server food access control device <NUM> the schedule is designated the server schedule. The server schedule that is based on the data input by the operator may take any form known to the Artisan. For example, the schedule may include a calendar and clock with times when the movable barrier <NUM> is to be moved to the restricted position <NUM> and times when the movable barrier <NUM> is to be moved to the access position <NUM>. Alternately, the schedule may take the form of a timer that sets a period between when the movable barrier <NUM> is to be moved to the restricted position <NUM> and times when the movable barrier <NUM> is to be moved to the access position <NUM>. The food access schedule can be adjusted by an operator at any time.

In an embodiment, the input device <NUM> includes a keypad <NUM> and a display <NUM>. In an embodiment, the display <NUM> is a small OLED display with a keypad <NUM> that permits quick and easy adjustments to the server schedule. Alternately, or in addition to the input device <NUM>, the data may be input into the server food access control device <NUM> wirelessly using a WiFi-capable device such as a smart phone or the like. Neither method requires an internet connection.

In an alternate embodiment, (shown superimposed on <FIG>), an exercise wheel <NUM> is disposed in the home cage <NUM>. The positioning mechanism <NUM> is connected to a brake <NUM> that interacts with (e.g. immobilizes/releases) the exercise wheel <NUM>. When the positioning mechanism <NUM> positions the brake <NUM> in an unbraked position with respect to the exercise wheel <NUM>, the exercise wheel <NUM> is free to rotate. When the positioning mechanism <NUM> positions the brake <NUM> in a braked position with respect to the exercise wheel <NUM>, the exercise wheel <NUM> is not free to rotate. Controlling whether the exercise wheel <NUM> is free to rotate aids in controlling an amount of exercise and associated caloric output. The exercise wheel <NUM> and the brake <NUM> can be provided in addition to the movable barrier <NUM>.

Alternately, there may be two positioning mechanisms <NUM>, one for the movable barrier <NUM> and another for the brake <NUM>. When there are two positioning mechanisms <NUM>, each may be independently controlled by the controller <NUM>. The brake <NUM> and the associated positioning mechanism <NUM> constitute an exercise wheel control device. There may be a respective exercise wheel control device in the server home cage <NUM> and/or in any or all of the client home cages <NUM>. The control logic for the brake(s) <NUM> may be the same as disclosed herein for the movable barrier(s) <NUM>. Alternately, the controller logic may be different.

In other alternate embodiments, the positioning mechanism <NUM> operates to control access to water, to an object, and/or to a region in the cage.

In an embodiment, the server food access control device <NUM> includes a real-time clock module <NUM> that keeps accurate time. The real-time clock module <NUM> includes a small battery that maintains accurate time during a loss of external power. In the server food access control device <NUM>, the controller <NUM> is designated a server controller <NUM>. The server controller <NUM> includes a server controller time clock <NUM>. Should the power supply be interrupted, the battery on the real-time clock module <NUM> will maintain the server controller time clock <NUM> and the server schedule. Once the power supply is restored, the client food access control devices <NUM> will communicate with the server controller <NUM> and synchronize their time and their schedule with the server controller time clock <NUM> and the server schedule.

<FIG> shows the client food access control device <NUM>. At a minimum, the client food access control device <NUM> includes the controller <NUM>, designated a client controller <NUM>, the positioning mechanism <NUM>, and the movable barrier <NUM>. The client controller <NUM> is in signal communication with the server controller <NUM>. The client controller <NUM> has its own schedule designated the client schedule. In the client controller <NUM> the client schedule is based on the data entered into the server controller <NUM>. The data entered into the server controller <NUM> may be transmitted to the client controller <NUM>. Alternately, a copy of the server schedule may be transmitted to the client controller <NUM> to be used as the client schedule. The client controller <NUM> includes a client controller time clock <NUM>. The client schedule in the client controller <NUM> is kept synchronized with the server schedule in the server controller <NUM>.

A food access control apparatus includes a server food access control device <NUM> and any number of client food access control devices <NUM>.

<FIG> shows an alternate example embodiment of the server food access control device <NUM> having a server controller <NUM> with a server controller time clock <NUM>, a real time clock module <NUM>, a stepper motor board <NUM>, a Hall effect sensor <NUM>, and a positioning mechanism <NUM> which can be a stepper motor. If the positioning mechanism <NUM> is a stepper motor, then a stepper motor board <NUM> may be required to help control the stepper motor. The Hall effect sensor <NUM> detects a magnetic force of a small magnet placed in the moveable barrier (not shown). When the moveable barrier moves between the access position and the restricted position, the Hall effect sensor detects the presence or absence of the magnet, providing feedback on the moveable barrier's position. Unlike the example embodiment of <FIG>, in this example embodiment there is no input device shown. Hence, data communication is wireless as previously described.

<FIG> is a perspective view of an example embodiment of the food access control device <NUM>, including a movable barrier housing <NUM> and a controller housing <NUM> with a controller housing cover <NUM>. Also shown are housing hooks <NUM> configured to secure the food access control device <NUM> to the cage's preexisting food hopper in an example embodiment, which is not meant to be limiting.

<FIG> is a perspective view of food access control device <NUM> with the controller housing cover <NUM> removed to show the server food access control device <NUM> with the server controller <NUM>, the real time clock module <NUM>, the stepper motor board <NUM>, and the positioning mechanism <NUM> (which can be a stepper motor). The stepper motor board <NUM>, and the positioning mechanism <NUM> are shown in their respective installed positions. The server controller <NUM> and the real time clock module <NUM> are shown elevated from their respective installed positions inside the controller housing <NUM> for clarity.

<FIG> is a perspective view of the food access control device <NUM> with an end cap removed to reveal the movable barrier <NUM>. In this example embodiment, the movable barrier <NUM> is cylindrical in shape and is configured to rotate about a longitudinal axis <NUM> of the cylinder. The storage area <NUM> is disposed within the movable barrier <NUM>. The movable barrier housing <NUM> has a housing opening <NUM> that aligns with a moveable barrier opening <NUM> in the movable barrier <NUM> when the movable barrier <NUM> is in the in the access position <NUM> as shown in <FIG>. The living area <NUM> is outside of the movable barrier housing <NUM> in the cage. Accordingly, when in the access position <NUM> shown, access is provided between the living area <NUM> and the storage area <NUM> in which food may be disposed.

<FIG> is a perspective view of the food access control device of <FIG> with the movable barrier in a restricted position <NUM>. To reach the restricted position <NUM>, the server food access control device <NUM> has rotated the movable barrier <NUM> about the longitudinal axis <NUM> from the access position <NUM> to the restricted position <NUM> shown. The moveable barrier opening <NUM> is moved out of alignment with the housing opening <NUM> and a solid portion <NUM> of the movable barrier <NUM> is moved into alignment with the housing opening <NUM>. The solid portion <NUM> blocks access between the living area <NUM> and the storage area <NUM> when the movable barrier <NUM> is in the restricted position <NUM>.

<FIG> is an exploded view of the food access control device <NUM> in which the movable barrier housing <NUM> is shown in phantom for sake of clarity. To rotate the movable barrier <NUM>, the positioning mechanism <NUM> / server (not visible in <FIG>) rotates a motor gear <NUM> which engages and rotates a cage gear <NUM>. The cage gear <NUM> is secured to the movable barrier <NUM> and thereby rotates the movable barrier <NUM> with the cage gear <NUM>. In the example embodiment show, the cage gear <NUM> and the movable barrier <NUM> are geometrically interlocked via a first feature <NUM> on the cage gear <NUM> that engages with a second feature <NUM> (see <FIG>) on a proximate end <NUM> of the movable barrier <NUM>. In the example embodiment shown, the first feature <NUM> includes a male stud <NUM> with an oval cross section and the second feature <NUM> includes a female socket <NUM> with a matching oval cross section that receives therein the male stud <NUM> as can be seen in <FIG>.

<FIG> is a side view of the food access control device <NUM> secured to the cage's preexisting food hopper <NUM>. In this example embodiment, the movable barrier housing <NUM> is secured under the food hopper <NUM>. The controller housing <NUM> is secured in a pocket <NUM> on the inside of the food hopper <NUM>. In this way, an operator will have access to the controller housing <NUM> and elements therein, while the movable barrier housing <NUM>, the movable barrier <NUM>, and the food are all under the food hopper <NUM> and within the confines of the cage when the food hopper <NUM> is in place.

<FIG> is a bottom perspective view of the food access control device <NUM> secured to the cage's preexisting food hopper <NUM> of <FIG>. The movable barrier <NUM> is in the access position <NUM>, so access would be provided between the living area <NUM> and the storage area <NUM>, and hence to food disposed in the storage area <NUM>.

<FIG> is a front view of the food access control device <NUM> secured to the cage's preexisting food hopper <NUM> that is, in turn, in position on the cage <NUM>. The food hopper <NUM> rests on an upper edge <NUM> of the cage <NUM>. The cage <NUM> and the food hopper <NUM> define a volume <NUM> in the cage <NUM> that is the living area <NUM>. Accordingly, the movable barrier <NUM> provides access between the living area <NUM> and the food in the storage area <NUM> when the movable barrier <NUM> is in the access position <NUM> and restricts access when in the restricted position <NUM> (not shown).

The apparatus described herein provides several benefits. A first benefit is efficiency. Currently available alternatives use multiple cables to power superfluous home cage components or require setup using proprietary computers and software. Only a single micro USB cable is required to make the food access control device <NUM> fully functional. Each client food access control device <NUM> may receive its schedule data through a wireless connection to the server food access control device <NUM>. This removes the need to individually adjust each client food access control device <NUM>. The server schedule can be adjusted at any time via the input device <NUM> on the server food access control device <NUM> or by wirelessly connecting to the server food access control device <NUM> via a WiFi-capable device, such as a phone, tablet, or laptop (not included). One food access control device <NUM> is required per home cage <NUM> and any number of food access control devices <NUM> can be used simultaneously in the food access control apparatus.

A second benefit is simplicity. The food access control device's <NUM> simple design allows it to be easily swapped in and out of each home cage <NUM> without taking up additional cage space by utilizing the already occupied space of the empty food hopper. Unlike some currently available alternatives, the food access control device <NUM> is designed to be used in the original home cage, reducing anxiety and behavioral changes in study animals due to cage transfers. Most alternatives were designed for use with single-housed animals, but the food access control device <NUM> can be used with either single-housed or group-housed animals. The food access control device's <NUM> small design does not interfere with the vivarium's existing cage rack, unlike currently available alternatives, which require animals to be housed away from standard housing racks.

A third benefit is cost savings: The food access control device <NUM> is significantly less expensive than known competitive products. Competitive products additionally require that the home cage lid be replaced with a cage lid that exposes the animals to room air rather than the filtered air provided through standard housing home cage lids.

Claim 1:
A food access control apparatus for home cages, the home cages comprising a food hopper, comprising:
at least two access control devices (<NUM>), each access control device (<NUM>) to be associated with his own home cage;
the at least two access control devices comprising:
a server access control device (<NUM>) to be associated with a server home cage (<NUM>), the server access control device (<NUM>) comprising a server controller (<NUM>, <NUM>); and
at least one client access control device (<NUM>) to be associated with a client home cage (<NUM>), the client access control device (<NUM>) comprising a client controller (<NUM>) in a signal communication with the server controller (<NUM>, <NUM>);
the server controller (<NUM>, <NUM>) configured to deliver access signals according to an access schedule based on data entered into the server controller (<NUM>, <NUM>) by an operator; and
the client controller (<NUM>) configured to receive an access schedule based on the data entered into the server controller (<NUM>, <NUM>);
each of the at least two access control devices (<NUM>) further comprising: a movable barrier (<NUM>) configured to be positioned in the respective home cage (<NUM>) between a storage area (<NUM>) and a living area (<NUM>) and configured to be movable between an access position (<NUM>) where there is unrestricted access to an item in the storage area from the living area and a restricted position (<NUM>) where the access is denied;
wherein the movable barrier (<NUM>) is moved between the access position (<NUM>) and the restricted position (<NUM>) in response to the access signals, and
wherein the movable barrier (<NUM>) is configured to fit entirely within a volume bounded by the home cage (<NUM>) and the food hopper of the home cage (<NUM>); and/or to be suspended from the food hopper of the home cage (<NUM>).