Charging of the battery for a mobile robot

Abstract

A power station may have a power source and a connector having at least one power contact for outputting power from the power source to charge a battery pack, a first auxiliary contact for delivering current to a load, and a second auxiliary contact for receiving a voltage signal. A current sensor may measure the current delivered via the first auxiliary contact. A controller may be configured to determine, at least in part based on the measured current and the received voltage signal, whether the load is a) a battery pack electrically coupled to a charger within a mobile robot, the charger being coupled to the power station via the connector; or b) a battery pack directly coupled to the power station via the connector.

Description

[0001] Cross - reference to related applications

[0002] This application claims the benefit of U.S. Provisional Patent Application No. 63 / 051,843, entitled "CHARGING OF BATTERIES FOR MOBILE ROBOTS", filed on July 14, 2020. The entire content of each of the above - mentioned applications is hereby incorporated by reference and made a part of this specification. Background Technical field

[0004] The present disclosure generally relates to mobile robots and charging stations, and more particularly to an improved safety system for engaging a charging station with a mobile robot. Background art

[0006] Mobile robots are used in many different industries to automate tasks that are typically performed by humans. Mobile robots can be autonomous or semi - autonomous and are designed to operate within a specified area and complete or assist humans in industrial tasks. In one example, a mobile robot is a mobile robot platform that can be used in a warehouse or other industrial setting to move and arrange materials by interacting with other cart attachments, robotic arms, conveyors, and other robotic implementations. Each mobile robot can include its own autonomous navigation system, communication system, and drive components. Summary of the invention

[0007] Example methods and systems for charging a mobile robot are disclosed herein. In one aspect, a method for charging a mobile robot includes the steps of: advancing the mobile robot towards a charger such that a protrusion of the charger is inserted into a recess of the mobile robot. The method includes advancing the mobile robot to move a shield on the protrusion of the charger from a closed position to an open position to expose one or more electrical contacts on the protrusion. The shield is biased towards the closed position. The method further includes advancing the mobile robot such that one or more electrical contacts in the recess of the mobile robot are electrically connected to one or more electrical contacts on the protrusion of the charger. The method includes advancing the mobile robot such that a magnetic field generated by a magnet on the mobile robot activates one or more reed switches on the charger. The method further includes advancing the mobile robot to actuate a momentary switch from an off position to an on position to activate the momentary switch, wherein the momentary switch is biased towards the off position. The method includes transmitting an electrical signal between the mobile robot and the charger using the electrical connection between one or more electrical contacts of the mobile robot and one or more electrical contacts of the charger to perform an electrical handshake.

[0008] The method includes sending a charging current from a charger to a mobile robot through an electrical connection between one or more electrical contacts of the charger and one or more electrical contacts of the mobile robot in response to the closing of one or more reed switches, activation of a momentary switch, and completion of an electrical handshake to charge the mobile robot.

[0009] In another aspect, a charger for charging a mobile robot includes a first charger electrical contact and a second charger electrical contact, both of which are configured to be electrically connected to corresponding first robot electrical contact and second robot electrical contact when the mobile robot engages the charger. The charger further includes a shield that can move between a closed position and an open position. The shield is configured to cover the first charger electrical contact and the second charger electrical contact in the closed position and expose the first charger electrical contact and the second charger electrical contact in the open position. The shield is configured to move from the closed position to the open position when the mobile robot engages the charger. The charger includes a biasing structure for biasing the shield toward the closed position. The charger further includes a momentary switch that can move between a disconnected position and a connected position. The momentary switch is biased toward the closed position and is configured to move from the closed position to the open position when the mobile robot engages the charger. The charger includes one or more reed switches having a closed configuration and an open configuration, and is configured to switch to the closed configuration by one or more magnets on the mobile robot when the mobile robot engages the charger.

[0010] The charger is configured to be capable of charging through the first charger electrical contact and the second charger electrical contact when the momentary switch is in the connected position and one or more reed switches are in the closed configuration. The charger is further configured to prohibit charging through the first charger electrical contact and the second charger electrical contact when the momentary switch is in the disconnected position or one or more reed switches are in the open configuration.

[0011] Various embodiments disclosed herein may relate to a power station, which may include a power source and a connector having at least one power contact for outputting power from the power source to charge a battery pack; a first auxiliary contact for delivering current to a load; and a second auxiliary contact for receiving a voltage signal. The power station may include a current sensor for measuring the current delivered via the first auxiliary contact. The controller may be configured to determine, at least in part based on the measured current and the received voltage signal, whether the load is: a) a battery pack electrically coupled to a charger within a mobile robot, the charger being coupled to the power station via the connector; or b) a battery pack directly coupled to the power station via the connector.

[0012] The controller can be configured to: monitor the temperature of the charger via the voltage signal when the load is determined to be a battery pack electrically coupled to the charger within the mobile robot. The controller can be configured to monitor the voltage of one or more battery cells of the battery pack via the voltage signal when the load is determined to be directly coupled to the battery pack of the power station. The power station can be configured to stop outputting power when the monitored temperature is higher than a threshold temperature. The power station can be configured to stop outputting power when the voltage signal monitoring the voltage of one or more battery cells indicates that the battery has been disconnected from the power station.

[0013] The connector can have a third auxiliary contact for transmitting another current to the load. The connector can have a fourth auxiliary contact for receiving another voltage signal. The current transmitted by the first auxiliary contact and the current transmitted by the third auxiliary contact can have substantially the same voltage. The power station can be configured to transmit current to the load via the first auxiliary contact at a substantially constant voltage.

[0014] The controller can be configured to: determine that the battery pack within the mobile robot is electrically coupled to the charger, which is coupled to the power station via the connector, when the measured current is within a first current range and the received voltage signal is within a first voltage range. The controller can be configured to: determine that the battery pack is directly coupled to the power station via the connector when the measured current is within a second current range and the received voltage signal is within a second voltage range. The controller can be configured to determine that the load is a failed battery pack when the measured current is within the second current range and the received voltage signal is lower than a threshold voltage value or when no voltage signal is received. The controller can be configured to determine that the load is a failed battery pack at least partially based on the measured current and the received voltage signal.

[0015] The battery pack can include: one or more battery cells and a connector coupled to the connector of the power station. The connector of the battery pack can include: at least one power contact for receiving power to charge the one or more battery cells; a first auxiliary contact for receiving current from the first auxiliary contact of the power station connector; and a second auxiliary contact for transmitting the voltage signal to the second auxiliary contact of the power station connector. The second auxiliary contact can be coupled to the one or more battery cells such that the voltage signal corresponds to the voltage of the one or more battery cells.

[0016] The battery pack may include a switch located between the at least one power contact and the one or more battery cells. The switch may have a non-conductive configuration that disconnects the at least one power contact from the one or more battery cells. The switch may have a conductive configuration that electrically couples the at least one power contact to the one or more battery cells for charging. The switch may include a contactor, solenoid, or relay, etc. The first auxiliary contact may be configured to supply current to the switch to place the switch in the conductive configuration, enabling charging of the one or more battery cells. The controller of the power station may be configured to determine that the load is directly coupled to the battery pack of the power station when the measured current is within a current range, and the amount of current provided to place the switch in the conductive configuration may be within the current range. Other embodiments may be used. For example, current may be supplied to a resistor (or other element) having a known resistance value in the battery pack to produce an amount of current within the current range.

[0017] The connector of the battery pack may include a third auxiliary contact for receiving another current. The battery pack may be configured to operate battery pack electronics from the another current such that the battery pack can be recharged when the one or more battery cells are fully discharged. The connector of the battery pack may include a fourth auxiliary contact for providing another voltage signal. The fourth auxiliary contact may be coupled to the one or more battery cells such that the voltage signal corresponds to another voltage associated with the one or more battery cells.

[0018] The charger may include: a connector coupled to the connector of the power station. The connector of the charger may include: at least one power contact for receiving power transmitted to the mobile robot; a first auxiliary contact for receiving current from the first auxiliary contact of the power station connector; and a second auxiliary contact for transmitting the voltage signal to the second auxiliary contact of the power station connector.

[0019] The charger may include a docking station configured to receive the mobile robot. The charger includes a temperature sensor, and the voltage signal may indicate the temperature measured by the temperature sensor. The charger may include a third auxiliary contact for receiving another current. The charger may be configured to use the another current to operate one or more sensors to detect whether the mobile robot is docked with the charger. The charger may be configured to use the another current to operate at least one momentary switch and / or at least one reed switch. The first auxiliary contact may be serially connected with a resistor (e.g., a resistor having a known resistance value) and the at least one momentary switch and / or the at least one reed switch such that when the at least one momentary switch and / or the at least one reed switch is turned on, a current is generated within a current range. The controller of the power station may be configured to: when the measured current is within the current range, determine that the load is a battery pack electrically connected to the charger within the mobile robot. The charger connector may include a fourth auxiliary contact for providing another voltage signal to the mobile robot indicating the charging voltage provided by the charger. The system may further include the mobile robot docked with the charger, and the mobile robot may include the battery pack. The battery pack may be removable from the mobile robot. The mobile robot may be configured to monitor the battery voltage of the battery pack and prohibit charging if the monitored battery voltage indicates that the battery pack has been removed from the mobile robot.

[0020] Various embodiments disclosed herein may relate to a battery pack including one or more battery cells and a connector having at least one power contact for receiving power for charging the one or more battery cells; a first auxiliary contact for receiving a current; and a second auxiliary contact for transmitting a voltage signal. The second auxiliary contact may be coupled to the one or more battery cells such that the voltage signal corresponds to the voltage of the one or more battery cells. There may be a switch between the at least one power contact and the one or more battery cells. The switch may have a non-conductive configuration that disconnects the at least one power contact from the one or more battery cells. The switch may have a conductive configuration that electrically couples the at least one power contact to the one or more battery cells for charging. The switch may include a contactor, a solenoid, or a relay.

[0021] The first auxiliary contact can be configured to supply the current to the switch to place the switch in the conducting configuration to enable charging of the one or more battery cells. The battery pack can be coupled to a power station, the power station being configured to determine that a load is directly coupled to the battery pack of the power station when the measured output current is within a current range, and the amount of current provided to place the switch in the conducting configuration can be within the current range. The connector of the battery pack can have a third auxiliary contact for receiving another current. The battery pack can be configured to operate battery pack electronics from the another current such that the battery pack can be recharged when the one or more battery cells are fully discharged. The current transmitted by the first auxiliary contact and the another current transmitted by the third auxiliary contact can have substantially the same voltage.

[0022] Various embodiments disclosed herein can relate to a charger for a mobile robot. The charger can include: a connector including: at least one power contact for receiving power to be transmitted to the mobile robot; a first auxiliary contact for receiving a current from the first auxiliary contact of the power station connector; and a second auxiliary contact for transmitting a voltage signal to the second auxiliary contact of the power station connector. The charger can have a docking station that can be configured to transmit power to the mobile robot.

[0023] The charger can have a temperature sensor, and the voltage signal can indicate the temperature measured by the temperature sensor. The connector can include a third auxiliary contact for receiving another current. The charger can be configured to operate one or more sensors using the another current to detect whether the mobile robot is docked with the charger. The charger can be configured to operate at least one momentary switch and / or at least one reed switch using the another current. The first auxiliary contact can be connected in series with a resistor and the at least one momentary switch and / or the at least one reed switch such that when the at least one momentary switch and / or the at least one reed switch is turned on, the current is generated within a current range. A controller of the power station can be configured to determine that a load is a battery pack electrically coupled to the charger within the mobile robot when the measured current is within the current range. The charger can include a fourth auxiliary contact for providing another voltage signal to the mobile robot indicating a charging voltage provided by the charger. The charger can further have the mobile robot docked with the charger, and the mobile robot can include the battery pack.

[0024] Various embodiments disclosed herein may relate to a method for charging a battery pack of a mobile robot. The method may include the steps of: transmitting current from a power station through a first contact of a connector of the power station to a load; measuring the current transmitted through the first contact; receiving a voltage signal through a second contact of the connector; and determining that the load is, at least in part, based on the measured current and the received voltage: a) a battery pack electrically coupled to a charger within the mobile robot, the charger being coupled to the power station via the connector; or b) a battery pack directly coupled to the power station via the connector. The method may include transmitting power from the power station through the connector to charge the battery pack.

[0025] The method may include determining that the load is a battery pack electrically coupled to the charger within the mobile robot, the charger being coupled to the power station via the connector. The method may include measuring the temperature of the charger, and the voltage signal received through the second contact of the connector may indicate the measured temperature. The method may include prohibiting charging in response to determining that the measured temperature exceeds a threshold temperature. The method may include determining that the load is a battery pack directly coupled to the power station via the connector.

[0026] The above summary is merely illustrative and not restrictive. Other aspects, features, and advantages of the systems, devices, and methods and / or other subject matter described in this application will become apparent in the teachings set forth below. This summary is provided to introduce a selection of concepts of the present disclosure. This summary is not intended to identify key or essential features of any subject matter described herein. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] For illustrative purposes, various examples are depicted in the drawings and should in no way be construed as limiting the scope of the examples. Various features of different disclosed examples may be combined to form additional examples, which are part of the present disclosure.

[0028] Figure 1 An example mobile robot according to some embodiments is shown.

[0029] Figure 2A Shown is Figure 1 a side view of the mobile robot.

[0030] Figure 2B Shown is Figure 1 details of the receiving interface of the mobile robot.

[0031] Figure 2C Shown is Figure 1 another detail of the receiving interface of the mobile robot.

[0032] Figure 3 Schematically shows a charging interface according to some embodiments, the charging interface including a support member and a protrusion extending from the support member.

[0033] Figure 4 Shows a top perspective view of an example charging interface according to some embodiments.

[0034] Figure 5A Shows from different angles Figure 4 of the example charging interface.

[0035] Figure 5B Shows an example charging interface with the shield in the open position.

[0036] Figure 5C Shows an example charging interface engaged with a mobile robot.

[0037] Figure 6 Shows separated from the support member Figure 4 of the example charging interface.

[0038] Figure 7 Shows Figure 4 a top perspective detail view of the charging interface, with the shield removed.

[0039] Figure 8A Shows Figure 4 a bottom perspective view of the charging interface, with the shield removed.

[0040] Figure 8B Shows an exemplary embodiment of the shield.

[0041] Figure 8C Is a cross-sectional view of an example charging interface.

[0042] Figure 9 Shows Figure 4 another bottom perspective view of the charging interface, with a portion of the protrusion removed to allow viewing of the sensor board.

[0043] Figure 10 Shows a detailed view of an example electromechanical switch according to some embodiments.

[0044] Figure 11 Shows an example sensor board according to some embodiments that can be disposed in the charging interface described herein.

[0045] Figure 12A Shows an example charging interface including a capture configuration with a shield according to some embodiments.

[0046] Figure 12B Shows an example charging interface with the shield in the open configuration.

[0047] Figure 13A Shows an example charging interface in a pivoting configuration with a shield in a closed configuration.

[0048] Figure 13B Shows an example charging interface in a pivoting configuration with a shield in an open configuration.

[0049] Figure 14 Shows a flowchart representing an example method of charging a mobile robot according to some embodiments.

[0050] Figure 15 Shows a block diagram of a system for charging a battery of a mobile robot.

[0051] Figure 16 Shows an exemplary embodiment of a connector for charging a battery of a mobile robot.

[0052] Figure 17 Shows an example flowchart of a method for charging a battery of a mobile robot. Detailed Description

[0053] Through the following description of the examples shown in the drawings, various features and advantages of the systems, devices, and methods of the techniques described herein will become more apparent. These examples are intended to illustrate the principles of the present disclosure, and the present disclosure should not be limited to the examples illustrated. In light of the principles disclosed herein, the features of the illustrated examples can be modified, combined, removed, and / or replaced, which will be apparent to those of ordinary skill in the art.

[0054] The present disclosure relates to an improved charging interface for a mobile robot. In some implementations, mobile or large robots are charged using charging contacts (e.g., pads) on the underside of the robot that are electrically connected to a charger bolted or otherwise attached to the floor. However, bolted chargers on the floor may not always be available or desirable. In some cases, dust or dirt can cause the charger to become dirty or malfunction. Some embodiments disclosed herein may use an elevated charging interface (e.g., above the floor or base of the charger) that can prevent dust and dirt from adversely affecting the charger.

[0055] In addition, there can be various problems with robot charging stations, such as arcing, premature current, and / or power management. For example, when charging, 10 to 100 amperes can flow from the charger to the robot at any given time (or other current amounts, depending on the type of robot). Without safety features, this amount of electricity can severely damage people or objects. For example, when there is no robot provided for charging and there is no safety feature to deactivate the charging current, a single piece of steel wool (or other object) can form sufficient electrical contact to initiate the charging current, which can cause a fire.

[0056] The safety features described herein include electromechanical, electromagnetic, electrical, and electrothermal features. Using these features in isolation and / or in combination can enable a mobile robot to charge while reducing the hazards to people and property. For example, electrical contact detection can be performed. In some cases, the charger can verify that the appropriate robot is connected before charging is enabled (e.g., an electrical handshake can be used to establish proper electrical contact between the appropriate charger and the appropriate robot). In some cases, the robot can verify that it is connected to the appropriate charger before initiating charging. Additionally or alternatively, stopping the robot charging before the charging pad is fully separated can prevent arcing, which can be dangerous.

[0057] Accordingly, improved charging interfaces and methods are described herein. An example charging interface can include a first charger electrical contact and a second charger electrical contact. The first charger electrical contact can be configured to electrically connect with a first robot electrical contact when the mobile robot engages the charger. The second charger electrical contact can be configured to electrically connect with a second robot electrical contact when the mobile robot engages the charger. The interface can also include a shield that can move between a closed position and an open position. The shield can be configured to cover the first charger electrical contact and the second charger electrical contact in the closed position. For example, the shield can be biased in the closed position. The shield can be configured to expose the first charger electrical contact and the second charger electrical contact in the open position. When the mobile robot engages the charger, the shield can be configured to move from the closed position to the open position.

[0058] The interface can also include a momentary switch, one or more electromagnetic (e.g., magnetic, reed) switches, and / or a temperature sensor. The momentary switch can move between a disconnected position and a connected position. The momentary switch can be biased toward the disconnected position and configured to move from the disconnected position to the connected position when the mobile robot engages the charger. The electromagnetic switch can have a closed configuration and an open configuration. The electromagnetic switch can be configured to be switched to the closed configuration by one or more magnets on the mobile robot when the mobile robot engages the charger.

[0059] In some embodiments, the charging interface can be configured to enable charging through the first charger electrical contact and the second charger electrical contact when the momentary switch is in the closed position and the one or more electromagnetic switches are in the closed configuration, and to disable charging through the first charger electrical contact and the second charger electrical contact when the momentary switch is in the open position or the one or more electromagnetic switches are in the open configuration. Reference will now be made to the accompanying drawings.

[0060] Mobile robot

[0061] Figure 1 An exemplary mobile robot 50 according to one embodiment is shown. The mobile robot 50 can include one or more wheels 51 and a front face 52 including a receiving interface 54 for connection to a charging interface (not shown). The mobile robot 50 can include a first electrical contact 56 and a second electrical contact 58 and an actuator 62 for actuating a shield on the charging interface. The first electrical contact 56 can include a plurality of connectors, and / or the second electrical contact 58 can include a plurality of connectors. The mobile robot 50 can also include one or more magnets 66 located near and / or inside the receiving interface 54.

[0062] Figure 2A A side view of the mobile robot 50 is shown. Figure 2B and Figure 2C Each shows a detailed view of the receiving interface 54. The first electrical contact 56 and the second electrical contact 58 can be seen. The mobile robot 50 can include an upper platform 70. The upper platform 70 can be a planar area, although any other suitable shape or structure can be used. The upper platform 70 can include locations for mounting other robotic appliances to the mobile robot 50. For example, the mobile robot 50 can interface with a charging interface as described herein, but additionally or alternatively interface with a movable cart, table, conveyor, robotic arm, and any other suitable application. The mobile robot 50 can include an outer housing or shield 74. The outer shield 74 can include a plurality of sidewalls connected together to enclose or substantially enclose the navigation system \ communication system \ power system and / or other components for operating the mobile robot 50.

[0063] As described herein, the mobile robot 50 includes a receiving interface 54 for connection to a charging interface. The receiving interface 54 may include a recess, such as formed in the front face 52 of the mobile robot 50. The recess may be elevated, such as above the wheel 51, above the axis of one or more of the wheels 51, or above the bottom of the housing or shield 74. In some cases, the housing or shield 74 may have a lower portion below the recess and an upper portion above the recess. The recess may be a generally or substantially horizontal slit in the housing of the mobile robot 50. In some cases, the horizontal slit or other recess may receive a charger interface that may be inserted into the recess to charge the mobile robot 50. In some embodiments, the horizontal slit or other recess may also allow light to pass to or from the navigation system of the mobile robot 50.

[0064] The first electrical contact 56 may be located on the upper side of the recess. For example, the first electrical contact 56 may be on the upper surface of the recess and, in some cases, may extend downward into the recess. The second electrical contact 58 may be located on the lower side of the recess. For example, the second electrical contact 58 may be on the lower surface of the recess and, in some cases, may extend upward into the recess. The first electrical contact 56 may include one or more conductive teeth. The first electrical contact 56 may be movable, such as in an overall up and down direction. The first electrical contact 56 may be biased downward, such as by a spring or other biasing mechanism. The second electrical contact 58 may include one or more conductive teeth. The second electrical contact 58 may be movable, such as in an overall up and down direction. The second electrical contact 58 may be biased upward, such as by a spring or other biasing mechanism. When the charging interface is inserted into the recess, the charging interface may move the first electrical contact 56 upward and / or move the second electrical contact 58 downward. During charging, the first electrical contact 56 and / or the second electrical contact 58 may be biased against corresponding electrical contacts on the charger.

[0065] In some cases, the first charging contact 56 and the second charging contact 58 of the mobile robot may protect the electrical contacts from debris or accidental contact with other objects. For example, because the electrical contacts are recessed, the housing or shield 74 of the mobile robot 50 may prevent foreign objects from contacting the electrical contacts during charging.

[0066] The mobile robot 50 may include an actuator 62 for actuating a shield on the charging interface, as discussed herein. The actuator 62 may be part of the outer housing or shield 74 of the mobile robot 50 and may be separate from the electrical contacts 56, 58 (e.g., in front of the electrical contacts 56, 58).

[0067] In some cases, one or more magnets 66 may be positioned inside the mobile robot 50 such that one or more magnets 66 are not exposed or visible from the outside of the robot 50. In some cases, one or more magnets 66 may be positioned outside the mobile robot 50. The one or more magnets 66 may be positioned in the recess or otherwise positioned on the receiving interface 54 of the mobile robot 50 such that the one or more magnets 66 can trigger the magnetically actuated switches as discussed herein.

[0068] The mobile robot 50 may be autonomous or semi-autonomous. The mobile robot 50 may include multiple sensors for sensing the environment. The sensors may include LIDAR and other laser-based sensors and / or rangefinders for mapping the surroundings of the robot. The mobile robot 50 may include a laser slit that includes a ranging or LIDAR-type laser contained therein. The mobile robot 50 may include a user interface (not shown) for manual input of instructions or information and / or for receiving information output from the mobile robot 50. In some embodiments, the control panel may additionally or alternatively be located on the side, under the panel, or in an unexposed location on the mobile robot 50.

[0069] The robot 50 can generally be oriented along the front-to-rear direction F-RV and along the left-to-right direction L-RT. The forward direction F can generally be along the forward movement of the robot. The reverse direction RV can be opposite to the forward direction. The left-to-right direction L-RT can be orthogonal to the front-to-rear direction F-RV. The left-to-right direction L-RT and the front-to-rear direction F-RV can be coplanar, such as in a generally horizontal plane.

[0070] The upper platform 70, the outer shroud 74, and / or any other components of the mobile robot 50 can be mounted on the chassis. Depending on the purpose and design of the mobile robot 50, various different components and structures can be mounted on the chassis. The support system 78 can include one or more support wheels 51 (e.g., 2, 3, 4, or more wheels). The wheels 51 can be connected to the chassis 140. In some cases, one or more of the wheels 51 can be casters. The wheels 51 can support the load on the chassis against the ground. In some embodiments, the wheels 51 can include individual or combined suspension elements (e.g., springs and / or dampers). Thus, in some embodiments, the wheels 51 can move (e.g., up and down) to accommodate uneven terrain, for shock absorption, and for load distribution. In some embodiments, the wheels 51 can be fixed such that they do not move up and down, and the ground clearance of the mobile robot 50 can be constant, regardless of the weight or load of the mobile robot 50. In some examples, one or more of the wheels 51 can be undriven.

[0071] The support system may include a drive assembly capable of providing acceleration, braking, and / or steering of the mobile robot 50. In some embodiments, the drive assembly drives one or more drive wheels (e.g., two wheels 51). These two wheels may be the wheels that directly guide the movement of the mobile robot 50. For example, if both drive wheels rotate in a first direction, the mobile robot 50 may move forward; if the two drive wheels move in a second direction, the robot may move in reverse; if the drive wheels move in opposite directions, or if only one of the drive wheels moves, or if the drive wheels move at different speeds, the robot may turn. Braking may be performed by slowing the rotation of the drive wheels, by stopping the rotation of the drive wheels, or by reversing the direction of the drive wheels. The drive assembly may be coupled (e.g., pivotally coupled) to the chassis. The drive assembly may be configured to engage the ground through a suspension system. The drive assembly may be at least partially located beneath the outer shroud 74 of the mobile robot 50.

[0072] Many variations are possible. For example, in some cases, a single drive assembly may be used, which may move the robot forward and / or backward, and a separate steering system may be used to effect steering, such as one or more steering wheels that may turn left or right. In some embodiments, the mobile robot 50 may include two, three, or four drive assemblies. In certain alternative embodiments, the mobile robot 50 includes only driven wheels and no non-driven support wheels. In some embodiments, the one or more drive assemblies may support at least some of the weight of the robot and / or payload. In some examples, the mobile robot 50 may include two drive wheels and two or four non-driven support wheels.

[0073] The mobile robot 50 may include one or more sensors for measuring the movement of one or more of the wheels 51 (e.g., driven wheels). The sensor system may be used to detect and / or calculate the rotation, position, orientation, and / or other kinematic information from the movement of the wheels 51. In some examples, multiple sensors may be used to determine the kinematic information of each wheel. For example, each wheel may be associated with an optical sensor and a magnetic sensor for determining wheel rotation. By providing redundancy in the kinematic information, using multiple sensors can be beneficial such that if one system is unable to transmit its readings to the controller for some reason (e.g., failure, environmental shock, etc.), then another (or others) can provide the information. Thus, a system failure may not mean that the controller becomes unaware of the kinematic information. Another benefit of multiple sensors is that the accuracy of the information can be improved because the controller can rely on a larger amount of data when determining what the possible true value is. Examples of optical sensors include encoders (e.g., rotary encoders, linear encoders, absolute encoders, incremental encoders, etc.). Examples of magnetic sensors include bearing sensors or other speed sensors. The mobile robot 50 may include other types of sensors, such as mechanical sensors, temperature sensors, distance sensors (e.g., rangefinders), and / or other sensors.

[0074] Charger and charging interface

[0075] Robots, such as the mobile robot 50 described herein, may sometimes need to be charged. The mobile robot 50 includes on-board electrical storage (e.g., one or more batteries), but this power can be depleted through use and / or simply over time. Chargers and charging interfaces can provide the mobile robot 50 with options, either manual-free or automatic, to recharge its electrical storage.

[0076] As described above, charging the battery of a mobile robot typically requires the transfer of current, which can pose safety risks such as arcing and fire. Additionally, charging an autonomous or semi-autonomous robot can include challenges related to the proper orientation, proper proximity, and / or proper electrical specifications (e.g., amperage, current) of the robot. The chargers and interfaces described herein can reduce or address these challenges.

[0077] In some embodiments, the charging interface may be set off the ground such that the mobile robot 50 can reach it from its side. For example, the charger or docking station may include a base that supports the charging interface. The charging interface may include a protrusion that extends generally horizontally from the body of the charger or docking station. The height of the protrusion may correspond to the height of a recess in the mobile robot 50 such that when the mobile robot advances towards the charger or docking station, the protrusion can be inserted into the recess of the mobile robot 50.

[0078] For example, in some embodiments, when the mobile robot 50 is driven until it reaches the docking station that houses the charging interface, the mobile robot 50 pushes the shield back to expose the charging contacts (e.g., plates) that were previously hidden beneath the shield. When the shield is pushed backward, corresponding electrical contacts (e.g., multiple sets of spring-loaded copper "teeth") mounted on the mobile robot 50 slide along and engage with the top and bottom charging plates. These conductive teeth on the mobile robot can refer to the first electrical contact 56 and the second electrical contact 58 described herein. Inside the charging interface can be a circuit (e.g., on a printed circuit board) having one or more (e.g., a set of) reed switches (e.g., which can be mounted beneath the top copper charging plate). These reed switches can be activated by a magnet (e.g., which can be hidden inside the mobile robot 50, e.g., between the electrical contacts 56, 58). As an additional layer of safety, there can also be a momentary switch (e.g., a snap switch) (e.g., mounted on the lower side of the charging interface 100), which can be activated only when the shield is pushed back far enough to engage the copper teeth (or other robotic electrical contacts 56, 58) with the copper charging plates without the risk of arcing. When both the reed switch and the momentary switch are activated, the charger can start charging the mobile robot 50. Since the required configuration of the magnet can be unique, the reed switch or other magnetic switches can provide a high level of security in ensuring that the mobile robot 50 has properly engaged the charging interface 100. In some cases, the charger and the mobile robot 50 can perform an electronic handshake for verification before enabling charging. Other alternatives are also possible. Various implementations of the charger and the charging interface will now be described.

[0079] Figure 3 The charger 100 is schematically shown and includes a support 108 and a protrusion 104 extending from the support 108. The charging interface 100 can include a shield 116 that at least partially covers the protrusion 104. The shield 116 can cover (partially or completely) or hide the first electrical contact 112 and the second electrical contact 114. In some cases, the shield 116 can include at least one brush 118 that can brush across and clean the first electrical contact 112 and / or the second electrical contact 114 as the shield 116 moves. In some cases, at least one wiper (e.g., a brass wiper) can be coupled to the shield 116 and can be configured to wipe the first electrical contact 112 and / or the second electrical contact 114 as the shield 116 moves. The charging interface can include a temperature sensor 132. The charging interface 100 can include an electromechanical switch 120 (e.g., a momentary switch) and / or one or more electromagnetic switches 124. The controller 128 can be in electrical communication with the first electrical contact 112 and the second electrical contact 114.

[0080] The protrusion 104 may include a housing configured to receive or support one or more of the elements described herein. The protrusion 104 may be oriented substantially parallel to the ground and / or may be elevated or spaced apart from the ground or base of the charger 100. The protrusion 104 may extend from the support 108 at substantially a right angle. The support 108 may be coupled (e.g., fixed) to the ground and may be shaped to avoid contact with the mobile robot 50 during charging. The protrusion 104 and / or the support 108 may be made at least in part of metal, plastic, and / or other rigid materials.

[0081] The shroud 116 may be one of the safety elements of the charging interface 100. The shroud 116 may be disposed at least in part on and / or around the protrusion 104, such as on or around the housing of the protrusion 104. The shroud 116 may cover or hide the first electrical contact 112, the second electrical contact 114, the brush 118, one or more electromagnetic switches 124, and / or the temperature sensor 132. In the closed position, the shroud 116 may be biased away from the support 108. When the shroud 116 is pushed into the open position, it may expose or reveal (e.g., partially or fully) one or more of the elements it has hidden. By forcing the shroud 116 into the open position, the mobile robot 50 may access the first electrical contact 112 and / or the second electrical contact 114 to electrically connect with them using the corresponding electrical contacts (e.g., the first electrical contact 56 and / or the second electrical contact 58). The first electrical contact 112 and / or the second electrical contact 114 may be disposed outside the housing of the protrusion 104.

[0082] The shroud 116 may be actuated between the open and closed positions in a variety of ways. In some embodiments, the mobile robot 50 cannot access the first electrical contact 112 or the second electrical contact 114 without actuating the shroud 116 to the open position or actuating the shroud 116 toward the open position. In some embodiments, the shroud 116 translates laterally (e.g., along the protrusion 104), as Figure 3As shown, as the shroud 116 is pushed back, the shroud 116 can engage the electromechanical switch 120. The electromechanical switch 120 can be a momentary switch or some other mechanically actuated switch. The electromechanical switch 120 can include a button, a lever arm, a hinge, or some other engagement feature that the shroud 116 directly engages as the mobile robot 50 pushes the shroud 116 backward. The electromechanical switch 120 can be biased to an off position (or non-conductive position) until the shroud 116 and / or the mobile robot 50 actuates it to an on (or conductive) position. In the on position, the electromechanical switch 120 can partially or fully enable the flow of electricity through the first electrical contact 112 and / or the second electrical contact 114, which can be subject to any other safety requirements that are met. Thus, the electromechanical switch 120 can be activated by the shroud when the mobile robot 50 has advanced far enough such that charging can be performed without arcing. Figure 10 An example of an electromechanical switch 120 that can be used is shown.

[0083] The shroud and / or the electromechanical switch 120 can be used as a safety check to verify that the mobile robot 50 is close enough to the electrical contacts 112, 114, that the mobile robot 50 is properly shaped and / or oriented relative to the electrical contacts 112, 114, and / or that the mobile robot 50 is mechanically stable enough to be coupled to the charging interface 100. If a different mobile robot or other object incompatible with the charger 100 approaches the charging interface but does not have a recess that is properly configured to receive the protrusion and a structure that is properly positioned relative to the recess to move the shroud 116 toward the open position when the protrusion is inserted into the recess, the shroud will remain in the closed position, covering the electrical contacts 112, 114 and preventing the object from making electrical contact with the electrical contacts 112, 114. Even if an incompatible object can move the shroud 116 partially toward the open position, exposing at least a portion of the electrical contacts 112, 114, the charger 100 can be configured to prohibit charging until the switch 120 has been activated. Thus, in some cases, an object will not be able to achieve charging unless it is properly configured (e.g., having a recess with sufficient depth and relative actuation structure) to move the shroud 116 far enough to trigger the switch 120. Also, if a compatible mobile robot 50 approaches the charger 100 but from an improper angle or orientation, the protrusion 104, the shroud 116, and / or the momentary switch 120 can prevent charging. For example, at the wrong angle, the protrusion 104 cannot extend far enough into the recess to move the shroud 116 sufficiently to activate the switch 120.

[0084] The charger 100 and / or the mobile robot 50 can be configured such that as the mobile robot 50 advances and after the electrical contacts 56 and 58 of the mobile robot 50 have been electrically connected to the electrical contacts 112 and 114 of the charger, the switch 120 is activated. Then charging can be achieved without arcing between the electrical contacts. During the detachment of the mobile robot 50 from the charger 100, the mobile robot 50 can be retracted from the charger and the switch 120 is disconnected while the electrical contacts 56 and 58 of the mobile robot 50 remain electrically connected to the electrical contacts 112 and 114 of the charger 100. This can avoid arcing between the electrical contacts as the mobile robot 50 is retracted from the charger 100.

[0085] The electromechanical switch 120 can be actuated by the movement (e.g., translation) of the shroud 116. In some examples, the electromechanical switch 120 can be directly actuated by the mobile robot 50. For example, in certain implementations, the electromechanical switch 120 can be disposed at or near the distal end of the charging interface 100 or the protrusion 104. In this way, the electromechanical switch 120 can be configured to be directly contacted by an actuator or a part of the mobile robot 50.

[0086] When actuated, the electromechanical switch 120 can be pressed into the interior of the protrusion 104 (e.g., further into the housing of the protrusion 104). Alone or in combination with the shroud 116, the electromechanical switch 120 can prevent the unintentional and / or unauthorized release of electricity into the first electrical contact 112 and / or the second electrical contact 114. Although not shown, there can be electrical communication between the electromechanical switch 120 and the controller 128 and / or with some other controller. The controller 128 can enable and / or increase the flow of electricity (e.g., current) to the first electrical contact 112 and / or the second electrical contact 114 in response to detecting that the electromechanical switch 120 is in the on position, which can be subject to any other safety requirements that are met. In some embodiments, the switch 120 can be non-conductive in the off position, thereby preventing current from flowing to the electrical contacts 112 and 114. The switch 120 can be conductive in the on position (e.g., when activated by the shroud 116 or the mobile robot 50) such that current can flow through the switch 120 to the electrical contacts 112 and 114, e.g., for charging the mobile robot 50. Thus, in some embodiments, the switch 120 does not communicate with the controller 128 and can, for example, directly prohibit charging in its non-conductive state.

[0087] Another safety mechanism for controlling the flow of electricity to the first electrical contact 112 and / or the second electrical contact 114 can include a magnetic safety mechanism, such as one or more magnetic and / or electromagnetic switches 124. As Figure 3As shown, the charging interface 100 may include one or more electromagnetic switches 124. The electromagnetic switch 124 may include a reed switch and / or some other electromagnetic switch. For example, the electromagnetic switch 124 may be disposed within the housing of the protrusion 104. In some embodiments, the electromagnetic switch 124 may be disposed near the distal end of the protrusion 104 (e.g., disposed away from the support 108), as Figure 3 shown. In some embodiments, such as the embodiments described below, the electromagnetic switch 124 may be disposed within the shroud 116 when the shroud 116 is in the closed position. In some embodiments, one or more electromagnetic switches 124 (e.g., reed switches) may be between the first electrical contact 112 and the second electrical contact 114.

[0088] When a sufficient number or configuration of the electromagnetic switches 124 have been switched on (e.g., half of them, all of them, or at least one in a parallel group), the charger 100 may be configured to enable and / or increase the flow of power to the first electrical contact 112 and / or the second electrical contact 114, which may be subject to any other safety requirements that are met. Although not shown in Figure 3 , the controller 128 may be in electrical communication with one or more electromagnetic switches 124. When the controller 128 receives an indication that a sufficient number or configuration of the electromagnetic switches 124 have been switched on, the controller 128 may enable the power flow, subject to any other safety requirements that are met. In some embodiments, one or more electromagnetic switches 124 may be non-conductive in the off configuration, thereby preventing current from flowing to the electrical contacts 112 and 114. One or more electromagnetic switches 124 may be conductive in the on configuration, such that current may flow through one or more electromagnetic switches 124 to the electrical contacts 112 and 114, e.g., for charging the mobile robot 50. Thus, in some embodiments, one or more electromagnetic switches 124 do not communicate with the controller 128 and may directly prohibit charging, e.g., when in the off or non-conductive state.

[0089] The electromagnetic switch 124 may be tuned to respond to a magnetic field from one or more magnets (e.g., one or more of the magnets 66 described above) in or on the mobile robot 50. The electromagnetic switch 124 may be biased in the off configuration (e.g., outside the presence of an appropriate magnetic field). In the presence of an appropriate magnetic field, the electromagnetic switch 124 may be configured to switch to the on configuration.

[0090] One or more of the electromagnetic switches 124 can switch to an on configuration and / or an off configuration at different times from each other. For example, the electromagnetic switches 124 can be spatially arranged relative to each other such that each electromagnetic switch can experience a different amount of magnetic field relative to the others. The electromagnetic switches 124 can be configured in a manner that requires the correct orientation of the mobile robot 50. For example, the charging interface 100 can be configured to prevent power flow to the first electrical contact 112 and / or the second electrical contact 114 until a threshold number of the electromagnetic switches 124 and / or the appropriate configuration of the electromagnetic switches 124 have been switched on. For example, multiple sets of electromagnetic switches 124 can be connected in parallel such that current can flow if any of the electromagnetic switches 124 in a parallel set are switched on. Each of the multiple parallel sets can include one or more electromagnetic switches 124, which can be connected in series. In some configurations, a series-connected set of electromagnetic switches 124 is conductive when all of the electromagnetic switches 124 in the set are switched on. Thus, in some cases, even if some of the electromagnetic switches 124 are switched on, the arrangement of the electromagnetic switches 124 can be in an off (or non-conductive) configuration. For example, if one electromagnetic switch 124 is switched on but other series-connected electromagnetic switches 124 are off, the set can be non-conductive. In some embodiments, the arrangement of the electromagnetic switches 124 can be in a conductive or conducting configuration when all of the series-connected electromagnetic switches 124 are conductive (e.g., conducting) for at least one parallel set. In some examples, the electromagnetic switches 124 may need to be in the on configuration for a threshold amount of time before enabling power flow. For example, the controller 128 can implement a timer before enabling charging. The electromagnetic switches 124 (e.g., reed switches) can prevent unintended current. For example, if an incompatible object moves the shield 116 sufficiently to expose the electrical contacts 112 and 144 and trigger the switch 120, the charger 100 will not enable the charging current unless one or more of the electromagnetic switches 124 (e.g., reed switches) are in the on configuration. Thus, if the incompatible object does not have a magnet configured to appropriately switch on the electromagnetic switches 124, charging will remain disabled. Additionally, the electromagnetic switches 124 can provide safety by ensuring that the mobile robot 50 is sufficiently close and / or appropriately oriented to prevent or reduce the likelihood of arcing between the mobile robot 50 and the charging interface 100.

[0091] The timing of turning on the electromagnetic switch 124 and the electromechanical switch 120 can be such that it does not occur simultaneously with the mobile robot 50 engaging the charger 100. Additionally or alternatively, the timing of turning off the electromagnetic switch 124 and / or the electromechanical switch 120 as the mobile robot 50 disengages from the charger 100 can be non-simultaneous. For example, in some examples, as the mobile robot 50 advances, the relative positions and / or sensitivities of the electromechanical switch 120 and the electromagnetic switch 124 with respect to corresponding actuators (e.g., the shroud 116 of the mobile robot 50, the actuator 62) and magnets (e.g., the magnet 66 of the mobile robot 50) can be configured such that the electromagnetic switch 124 is turned on before the electromechanical switch 120 is turned on. Additionally or alternatively, it can be configured such that as the mobile robot 50 retracts from the charger 100, the electromechanical switch 120 is turned off before the electromagnetic switch 124 is turned off. This can prevent arcing as the mobile robot 50 separates from the charging interface 100. Other alternatives are possible (e.g., the electromechanical switch 120 is turned on before the electromagnetic switch 124 is turned on and / or the electromechanical switch 120 is turned off after the electromagnetic switch 124 is turned on).

[0092] The electromagnetic switch 124 can be in a specific orientation to enhance the functionality and / or reliability of the safety mechanism. Multiple electromagnetic switches 124 can be arranged in parallel with each other. Additionally or alternatively, multiple electromagnetic switches 124 can be arranged in series with each other. The series-connected electromagnetic switches 124 can facilitate the direction safety check of the mobile robot 50. For example, the series-connected electromagnetic switches 124 may not all be turned on unless the mobile robot 50 is properly positioned with respect to each of the electromagnetic switches 124 connected in series. Moreover, the parallel group of electromagnetic switches 124 can provide an acceptable position range for the mobile robot 50. For example, if the mobile robot 50 advances past a group of electromagnetic switches 124 such that they are no longer activated by the magnet, there can be another group of electromagnetic switches 124 further along the movement path to be triggered by the magnet of the mobile robot 50. The parallel group of electromagnetic switches 124 can provide redundancy such that if one or more of the electromagnetic switches 124 are inoperable, the function of the electromagnetic switches 124 is retained. In some examples, eight electromagnetic switches 124 are provided such that two groups of electromagnetic switches 124 are arranged in parallel with each other, where each group of electromagnetic switches 124 includes four electromagnetic switches 124 arranged in series, as Figure 9 shown. Other configurations are also possible (e.g., Figure 11 the configuration shown).

[0093] The charging interface 100 may include one or more cleaning elements that improve the lifespan of the charging interface 100 and / or the electrical components of the mobile robot 50. For example, the charging interface 100 may further include a brush 118 configured to clean one or more electrical contacts 112, 114 of the charging interface 100 and / or the mobile robot 50. The brush 118 may be disposed near the distal end of the protrusion 104, which may allow it to contact the target electrical contact. As shown, the brush 118 may be at least partially disposed over one or both of the first electrical contact 112 and / or the second electrical contact 114 of the charger 100. The brush 118 may be coupled to the shroud 116 such that when the shroud 116 is actuated, the brush 118 brushes along the first electrical contact 112 and / or the second electrical contact 114. The brush 118 may include rigid or flexible bristles that include metal, plastic, and / or some other suitable material. In Figure 3 the figure, one brush 118 configured to clean the first electrical contact 112 is shown. Although not shown, the shroud 116 may include a second brush for cleaning the second electrical contact 114. Alternatively, the size and position of the brush 118 may be set to clean both the first electrical contact 112 and the second electrical contact 114. For example, the brush 118 may be wound inside the shroud 116. The brush 118 may be configured to be removably coupled to the shroud 116, such as so that it can be replaced or removed for cleaning. In some embodiments, at least one brush may be coupled to the protrusion 104 (e.g., to the housing of the protrusion 104) and may be used to clean one or more electrical contacts 56, 58 on the mobile robot 50. The brush may be positioned distally of the charger electrical contacts 112, 114 such that as the mobile robot 50 advances, the electrical contacts 56, 58 of the mobile robot 50 slide over the brush. In some cases, the brush 118 disclosed herein may be movable and biased towards the target contact to ensure an improved connection between the brush 118 and the electrical contact.

[0094] Another safety feature may help ensure the proper operation of the electrical components. If there is an incorrect connection and / or a damaged electrical component in one or both of the charging interface 100 and / or the mobile robot 50, a large amount of heat may result. Such heat may represent a problem that needs to be addressed before charging can occur or continue at the charging interface 100. For example, if one or more of the electrical contacts 112, 114, 56, and / or 58 become dirty, the transfer of the charging current will generate a large amount of heat, which, if unchecked, will damage the charger 100 and / or the mobile robot 50. Thus, in some examples, the charging interface 100 includes a temperature sensor 132. The temperature sensor 132 may be in electrical communication with the controller 128 to transmit an electrical signal.

[0095] The temperature sensor 132 can be configured to detect a temperature that exceeds a threshold safe temperature. The temperature sensor 132 can provide a measurement representative of the temperature at the electrical contacts 112 and / or 114 of the charger. In some cases, the temperature sensor 132 can be configured to be in thermal communication (e.g., radiative, conductive) with the receiving interface 54 of the mobile robot 50 or some other portion thereof. The temperature sensor 132 can be configured to enable the flow of electrical power to the first electrical contact 112 and / or the second electrical contact 114 unless it detects that the temperature sensor 132 exceeds the threshold safe temperature. The temperature sensor 132 can be configured to prohibit the flow of electrical power to the first electrical contact 112 and / or the second electrical contact 114 if a temperature above the threshold is measured. The temperature can be checked before, during, and / or after charging. For example, when the charging interface 100 is charging the battery of the mobile robot 50, the temperature sensor 132 can detect a temperature above the threshold or a sudden increase in temperature at or near the temperature sensor 132, and can prohibit the supply of power to the first electrical contact 112 and / or the second electrical contact 114. In some examples, the temperature sensor 132 can additionally or alternatively send a signal to the mobile robot 50 to disconnect the electrical connection, thereby preventing damage to the mobile robot 50.

[0096] The controller 128 can provide another safety feature of the charging interface 100. The controller 128 of the charger can be configured to verify that the mobile robot 50 is a compatible or approved device before allowing charging. In some embodiments, the mobile robot can verify that the charger is compatible or approved before enabling charging of the mobile robot 50. This verification can be performed by exchanging information between the mobile robot 50 and the charger 100. For example, digital information such as a code or password can be exchanged for verification. In some embodiments, analog signals can be used for verification. Various suitable electrical handshake protocols can be used to enable the charger 100 to verify the mobile robot 50, and / or to enable the mobile robot 50 to verify the charger 100. As an example, when an electrical connection is established between the charger 10 and the mobile robot 50 (e.g., after the shroud has been moved to the open position, the mechanical switch 120 has been closed, and the magnetic switch 124 is in the closed configuration), the charger can send a first verification signal to the mobile robot 50. The mobile robot 50 can be configured to recognize the first verification signal (which can serve as verification of the charger 100). The mobile robot 50 can be configured to send a second verification signal to the charger 100 in response to the first verification signal. The charger 100 can be configured to recognize the second verification signal (which can serve as verification of the mobile robot 50), and in response, the charger 100 can enable charging. If the charger does not receive the second verification signal as a response, it does not allow charging. In some embodiments, the electrical handshake can be at low voltage and / or low energy, which can make the system safer before achieving high power. Various other suitable handshake or verification protocols can be used. The handshake or other verification protocol can be initiated in response to the activation of the switch 120 (e.g., momentary switch).

[0097] It is desired that the mobile robot 50 verify the presence of appropriate current and / or voltage at the first electrical contact 112 and / or the second electrical contact 114 before allowing the charging power flow to pass through. As discussed herein, the charger may verify the mobile robot 50 and / or the mobile robot 50 may verify the charger 100. Thus, in some examples, the controller 128 may participate in an electrical handshake to ensure that it is safe to enable the power flow through the electrical contacts 112, 114. After the electrical contacts 112, 114 are electrically connected to the electrical contacts 56, 58 of the mobile robot 50, but before the charging current is enabled (e.g., even after all other safety checks have passed), the controller 128 may first send a test electrical signal (e.g., a specific current, a specific voltage) to the mobile robot 50. In some examples, the mobile robot 50 may provide its own safety verification by sending a test electrical signal to the charging interface 100. If the test is satisfied on the mobile robot 50 side, the mobile robot 50 may send a clearance signal to the controller 128. When the controller 128 receives the clearance signal in return, the controller 128 may be configured to enable the charging current to flow to the electrical contacts 112, 114.

[0098] Figure 4 A top perspective view of an example charging interface 200 according to some embodiments is shown. The charging interface 200 shows a protrusion 204 extending from a support 208. A shroud 216 is disposed around the protrusion 204 to allow the shroud 216 to translate in response to actuation of the mobile robot 50. As shown, the shroud 216 is shaped to fit around the protrusion 204 to reduce the amount of lateral play of the shroud 216 during actuation. The protrusion 204 may taper at the distal end to facilitate a better coupling with the receiving interface 54 of the mobile robot 50. For example, the receiving interface 54 on the mobile robot 50 may flare at the opening leading to the recess, which may help to receive the protrusion 204 into the recess.

[0099] Note that the charging interface 200 (and any other charging interface described herein) may include one or more features of the charging interface 100 or any other charging interface embodiment described above. Additionally, elements sharing the same name may share one or more common features in some examples. Thus, unnecessary repetitive descriptions are reduced.

[0100] Figure 5A is shown in a different perspective view Figure 4 of the example charging interface 200, where the shroud is in the closed position. Figure 5B An example charging interface 200 with the shroud in the open position is shown. As shown, the first electrical contact 212 and the second electrical contact 214 of the protrusion 204 can be seen. The charging interface 200 also includes an electromechanical switch 220, which can be in Figure 5AAs seen in. The protrusion 204 is shown as being disposed above and parallel to the ground. The first electrical contact 212 is on the upper side of the protrusion 204, while the second electrical contact 214 is on the lower side of the protrusion 204, for example, facing downwards. This structure can prevent objects from inadvertently contacting the electrical contacts 212 and 214. For example, an object that lands on the charging interface 200 may contact the upper electrical contact 212, but not the lower electrical contact 214, thus preventing a complete connection. This is an additional safety feature and a benefit of the raised protrusion 204 for the charging interface 200.

[0101] Figure 5C A mobile robot 50 engaged with the charging interface 200 is shown. The protrusion 204 extends into a recess in the mobile robot 50. An actuator 62 on the mobile robot 50 pushes the shield 216 along the protrusion 204 to an open position, thereby exposing the first electrical contact 212 and the second electrical contact 214 on the charging interface 200. Corresponding electrical contacts 56 and 58 on the mobile robot can be electrically connected to the first electrical contact 212 and the second electrical contact 214 of the charging interface 200. Although not shown in Figure 5C A magnet in the mobile robot 50 can be close enough to one or more electromagnetic switches 124 (e.g., reed switches), which can be inside the protrusion 204, such that one or more electromagnetic switches 124 transition to an on or conductive configuration. When the shield 216 moves to Figure 5C the position shown, the shield 216 can push a switch 220 (e.g., a momentary switch). Optionally, the charger and the mobile robot 50 can perform an electrical handshake protocol for verification before the charger allows charging.

[0102] Figure 6 An example charging interface 200 decoupled from the support 208 is shown. The charging interface 200 includes a first wire 236 and a second wire 238 that are in electrical communication with the first electrical contact 212 and the second electrical contact 214, respectively ( Figure 4 not visible in Figure 6 ). If the required safety checks are met, charging and signal power can be transmitted through the wires 236, 238 to the corresponding electrical contacts 212, 214 and electrical contacts 56, 58 of the mobile robot 50. The wires 236 and / or 238 can be used to transmit data or other signals, such as to a controller 128. For example, a signal can be transmitted from the first electrical contact 212 and / or the second electrical contact 214 to the controller 128 for performing an electrical handshake as discussed here. Data or other signals can be transmitted in the other direction, such as from the controller to the first electrical contact 212 and / or the second electrical contact 214. In some embodiments, the controller can be between the wires 236, 238 and the first electrical contact 212 and the second electrical contact 214, for example, on Figure 9 the printed circuit board shown.

[0103] Figure 7 shows Figure 4 a top perspective detail view of the charging interface 200 of , with the shield 216 removed. The first electrical contact 212 and the second electrical contact 214 can be seen. A portion of each of the electrical contacts 212, 214 is disposed along the tapered portion of the protrusion 204 near the distal end of the protrusion 204. The brush 218 of the charging interface 200 is shown in Figure 7 as being disposed on the first electrical contact 212. In some examples (not shown), a corresponding brush can be disposed under the second electrical contact 214. The brush 218 can be configured to translate with the shield 216 such that the translation of the brush 218 rubs against the first electrical contact 212 to clean it.

[0104] A biasing member 242 (e.g., a spring) is shown as being disposed along one side of the protrusion 204. The biasing member 242 is coupled to the shield 216 (not shown) to bias the shield 216 toward the disconnected or closed position. A corresponding biasing member 244 ( Figure 7 not shown in Figure 7 ) is disposed on the opposite side of the protrusion 204 and is also coupled to the shield 216 ( Figure 7 not shown in Figure 7 ). Any suitable biasing structure can be used to bias the shield toward the closed position. For example, a single spring can be used. In some cases, a compressible element can be compressed as the shield 216 moves toward the open position and can rebound to push the shield 216 back to the closed position.

[0105] Figure 8A shows Figure 4 a bottom perspective view of the charging interface 200 of , with the shield 216 removed. The second electrical contact 214 and the biasing member 244 can be clearly seen. As shown, one or more of the biasing member 242 and / or the biasing member 244 can be disposed within corresponding recesses in the sides of the protrusion 204.

[0106] Figure 8B shows the shield 216 removed from the protrusion 204. The shield 216 can include the brush 218. The brush 219 can be connected to the shield 216 such that the brush 218 moves with the shield 216 to clean the first electrical contact 212. The brush 218 can be connected to the top surface within the shield 216. A similar brush can be connected to the bottom surface within the shield 216. The brush can be removably connected to the shield, or can be adhered to the shield, or can use any other suitable connection mechanism or technique.

[0107] Figure 8C is a cross-sectional view of a portion of the charging interface 200. Figure 8CThe cross-section is taken through the center of the protrusion 204. The charging interface 200 may include a circuit 250, which may be located between the first electrical contact 212 and the second electrical contact 214. The circuit 250 may be on a printed circuit board (PCB). Figure 9 A bottom perspective view of the charging interface 200 of Figure 4 is shown, where a portion of the protrusion 204 is removed to allow viewing of the interior of the protrusion 204. The circuit 250 includes a plurality of electromagnetic switches 254 (e.g., disposed on the underside of the PCB). The electromagnetic switches 254 may be disposed above the second electrical contact 214 (not shown) and / or below the first electrical contact 212. Note that Figure 9 the view of

[0108] is taken from below the protrusion 204. As shown, the circuit 250 includes two sets of electromagnetic switches 254 arranged in parallel. Each set includes four electromagnetic switches 254, and the individual electromagnetic switches 254 within each set are connected in series with each other. The first set of electromagnetic switches 254 may be closer to the distal end of the protrusion than the second set of electromagnetic switches 254. Thus, if the mobile robot 50 is to move forward to a first position, its magnet may activate the first set of electromagnetic switches 254 without activating the second set of electromagnetic switches 254. If the mobile robot 50 moves further forward to a second position, its magnet may activate the second set of electromagnetic switches 254 but not the first set. Thus, the parallel sets of electromagnetic switches 254 may provide a range of positions where the mobile robot 50 can be charged. The sets of electromagnetic switches 254 connected in series may be arranged generally transverse to the direction of the protrusion 204. Thus, if the mobile robot 50 is misaligned such that the electrical contacts 56, 58 are not properly aligned with the charging contacts 212, 214, the magnet of the mobile robot 50 may be positioned to activate some but not all of the series electromagnetic switches 254. Thus, charging is not prohibited due to misalignment of the mobile robot 50. Figure 9 a position not shown in

[0109] Figure 10Shows a detailed view of an example electromechanical switch 220 according to some embodiments. The electromechanical switch 220 includes a base 304, a biasing member 308, an arm 312 extending from the biasing member 308, and an engagement feature 316. The base 304 can be coupled (e.g., fixedly, removably) to the protrusion 204. The biasing member 308 can be coupled to the base 304 to allow actuation of the biasing member 308. The biasing member 308 can be a cantilever spring (e.g., as shown) or some other type of spring. Any suitable biasing structure can be used, such as a spring or a compressible elastic material. The arm 312 can extend from the biasing member 308 to allow the engagement feature 316 to have a better engagement with a corresponding actuating member (e.g., a part of the shroud 216, an actuator 62 of the mobile robot 50). The arm 312 can be substantially rigid to maintain the orientation of the engagement feature 316 relative to the biasing member 308. As shown, the engagement feature 316 can include a rotational feature to reduce friction between the engagement feature 316 and the corresponding actuating member. Other electromechanical switches are possible. The switch 220 can be a momentary switch or a biased switch. The switch 220 can be biased to an off or non-conductive position.

[0110] Figure 11 Shows an example circuit 400 (e.g., on a printed circuit board) that can be disposed in the charging interface described herein according to some embodiments. The circuit 400 can be on a circuit board 402. The circuit 400 can include a plurality of electromagnetic switches 404. The electromagnetic switches 404 can be arranged in parallel and / or in series, as discussed herein. As shown, the circuit 400 includes 45 electromagnetic switches 404, where 9 groups of electromagnetic switches 404 are arranged in parallel. Each group includes 5 electromagnetic switches 404 connected in series with each other. In some embodiments, the electromagnetic switches 404 can be in electrical communication with a communication interface 408. In some examples, the circuit or another controller can determine whether a sufficient number of electromagnetic switches 404 have been switched to the on position. If a sufficient number of electromagnetic switches 404 have been switched to the on position, the communication interface 408 can send a signal to a controller (e.g., Figure 3 controller 128) to indicate that a safety feature has been satisfied. As discussed herein, power flow can be achieved when other required safety features are satisfied. Other orientations, arrangements, and numbers of electromagnetic switches 404 are possible.

[0111] Figure 12A Shows an example charging interface 500 including a capture configuration of a shroud 516 according to some embodiments. The charging interface 500 includes a protrusion 504, a shroud 516, and an engagement element 560. The protrusion 504 can be shaped similar to the protrusion 204 described above.

[0112] The shield 516 can have an open and closed configuration that mimics a catcher. The shield 516 can include a first part or plate 516a and a second part or plate 516b. The first plate 516a can pivot about a first hinge 552, and the second plate 516b can pivot about a first hinge 554. One or both of the hinges 552, 554 can be oriented substantially horizontally, substantially parallel to the ground, and / or substantially parallel to the top of the protrusion 504. One or both of the hinges 552, 554 can be oriented substantially orthogonal to the direction in which the protrusion extends and / or orthogonal to the direction of movement of the mobile robot during engagement with the charging interface 500. As the mobile robot 50 approaches the shield 516, the actuator of the mobile robot 50 can contact a first buffer 556 and a second buffer 558 coupled to the respective first plate 516a and second plate 516b. In response to this contact, the first plate 516a can rotate upward to expose a first electrical contact thereunder. Similarly, the second plate 516b can rotate downward to expose a second electrical contact. Figure 12B The open configuration is shown. The plates 516a, 516b can be biased in their respective closed positions. First wire 536 and second wire 538 are shown, which are electrically coupled to the first electrical contact and the second electrical contact. In some embodiments, the distal ends of the first plate 516a and / or the second plate 516b can have corresponding rollers 556 and 558 that can roll along the front of the mobile robot 50 as the plates 516a, 516b open.

[0113] The engagement element 560 can be configured to contact a corresponding element of the mobile robot 50. The engagement element 560 can be configured to contact a distal portion of the receiving interface 54 of the mobile robot 50 and translate to actuate an electromechanical switch (not shown). In some examples, the engagement element 560 is an electromechanical switch and can be actuated directly by the mobile robot 50. For example, a wall or other structure within the recess of the receiving protrusion 504 can be positioned to press or otherwise actuate the engagement element 560 (which can be a momentary switch or other switch type). In some embodiments, when one of the plates 516a or 516b is opened a sufficient amount, they can push the momentary switch.

[0114] Figure 13A An example charging interface 600 with a pivoting configuration of a shield 616 is shown in accordance with some embodiments. Figure 13A The shield 616 is shown in the closed position, Figure 13B The shield 616 is shown in the open position. The charging interface 600 includes a protrusion 604, a first electrical contact 612, a second electrical contact ( Figure 13BInvisible) and the shield 616. The shield 616 can pivot, for example, about an axis that is substantially vertical or substantially perpendicular to the ground. As the mobile robot 50 approaches, the shield 616 can pivot via a structure on the mobile robot 50 to expose the first electrical contact 612 and a second electrical contact (not shown). As shown, the respective plates of the shield 616 can be configured to rotate together about the same axis. However, in some examples, the respective plates of the shield 616 can have their own axis of rotation. Additionally or alternatively, the respective axes of rotation can be parallel to each other. Other options are possible.

[0115] Figure 14 A flowchart showing an example method 700 for charging a mobile robot according to some embodiments is shown. The method can be performed by one or more of the elements described herein. For example, the steps of the method can be performed by a charging interface (e.g., charging interface 100, charging interface 200, charging interface 500, charging interface 600), a mobile robot (e.g., mobile robot 50), and / or parts of one or both, or any other embodiment disclosed herein.

[0116] At block 704, the method 700 includes advancing the mobile robot toward the charger such that a protrusion of the charger is inserted into a recess of the mobile robot. At block 708, the method 700 includes advancing the mobile robot to move a shield on the protrusion of the charger from a closed position to an open position to expose one or more electrical contacts on the protrusion. The shield can be biased toward the closed position.

[0117] Advancing the robot can cause the shield to actuate an instantaneous switch from an off position to an on position. In some embodiments, advancing the robot causes a part of the robot to directly actuate the instantaneous switch from the off position to the on position. The shield can slide linearly along the protrusion from the closed position to the open position. In some examples, the shield pivots between the closed position and the open position. In some examples, the shield includes an upper portion that pivots upward to expose upper electrical contacts on the protrusion and a lower portion that pivots downward to expose lower electrical contacts on the protrusion.

[0118] At block 712, the method 700 can include advancing the mobile robot such that one or more electrical contacts in a recess of the mobile robot are electrically connected to one or more electrical contacts on a protrusion of the charger. The recess on the mobile robot can include a substantially horizontal slit. At block 716, the method 700 includes advancing the mobile robot such that a magnetic field generated by a magnet on the mobile robot closes one or more reed switches on the charger.

[0119] At block 720, method 700 includes advancing the mobile robot so as to actuate the momentary switch from an open position to a closed position to activate the momentary switch. The momentary switch is biased toward the closed position. In some examples, as the mobile robot advances, one or more reed switches close before the momentary switch is activated.

[0120] At block 724, method 700 includes transmitting an electrical signal between the mobile robot and the charger using an electrical connection between one or more electrical contacts of the mobile robot and one or more electrical contacts of the charger to perform an electrical handshake. The electrical handshake can include the charger verifying the mobile robot and / or the mobile robot verifying the charger.

[0121] At block 728, method 700 includes sending a charging current from the charger to the mobile robot. The charging current can pass through an electrical connection between one or more electrical contacts of the charger and one or more electrical contacts of the mobile robot. Block 728 can be performed in response to one or more reed switches closing, activation of the momentary switch, and completion of the electrical handshake. Thus, in some embodiments, various safety measures must be met before the charging current is transferred from the charger to the mobile robot.

[0122] In some examples, the charger includes upper electrical contacts on an upper side of the protrusion and lower electrical contacts on a lower side of the protrusion. The mobile robot can include upper electrical contacts located on an upper side of the recess and lower electrical contacts located on a lower side of the recess. The protrusion can extend substantially horizontally and / or can be raised above the ground.

[0123] Method 700 can include cleaning one or more electrical contacts on the protrusion of the charger as the shroud moves. In some examples, method 700 includes monitoring the temperature at the protrusion of the charger and prohibiting the charging current when the monitored temperature is higher than a threshold temperature.

[0124] Method 700 can further include retracting the mobile robot from the charger to deactivate the momentary switch, and in response to deactivation of the momentary switch, stopping the charging current to deactivate charging of the mobile robot. Method 700 can include retracting the mobile robot such that the magnet moves away from one or more reed switches to open one or more reed switches. Additionally, method 700 can include retracting the mobile robot such that the shroud moves from an open position to a closed position to cover one or more electrical contacts on the protrusion of the charger, and retracting the mobile robot such that the protrusion of the charger is withdrawn from the recess of the mobile robot. In some examples, as the mobile robot is retracted, after the momentary switch is deactivated, one or more reed switches close.

[0125] The charger can be configured to enable charging when all four safety checks are performed: when the momentary switch 120 is closed, when one or more reed switches 124 are in the closed configuration, when the measured temperature is below a threshold, and when the electronic handshake or authentication has been completed. If the momentary switch 120 is open, or if one or more reed switches 124 are in the open configuration, or if the measured temperature is above the threshold, or if the electronic handshake or authentication has not been completed, the charger can prohibit charging.

[0126] Other combinations are possible. Any combination of the four safety checks can be used. For example, the charger can be configured to enable charging when three safety checks are performed, such as when the momentary switch 120 is closed, when one or more reed switches 124 are in the closed configuration, and when the electronic handshake or authentication has been completed. In this embodiment, the temperature sensor can be omitted. If the momentary switch 120 is open, or if one or more reed switches 124 are in the open configuration, or if the electronic handshake or authentication has not been completed, the charger can prohibit charging.

[0127] The charger can be configured to enable charging when two safety checks are performed, such as when the momentary switch 120 is closed and when one or more reed switches 124 are in the closed configuration. If the momentary switch 120 is open or if one or more reed switches 124 are in the open configuration, the charger can prohibit charging. In some cases, a single safety check can be performed, such as using the momentary switch or one or more reed switches.

[0128] Many variations are possible. For example, one or more reed switches can be omitted in some embodiments. The momentary switch can be omitted in some embodiments. In some embodiments, the switch 120 is not a momentary switch and is not biased to the open position. For example, as the mobile robot retracts from the charger 100, the structure of the mobile robot 50 can be configured to trigger the switch 120 to open. In some embodiments, the protrusion of the charging interface can include only one electrical contact instead of two, as shown. In some cases, a second electrical contact can be established elsewhere. In some cases, two protrusions can be used, each having one electrical contact.

[0129] Load identification

[0130] See Figure 15 , in some embodiments, a power station 800 can be used to charge the battery pack 802 of the autonomous mobile robot 50. The battery pack 802 can be removed from the mobile robot 50. In Figure 15In [the figure], two battery packs 802a and 802b are shown, where the first battery pack 802a is removed from the mobile robot 50, and the second battery pack 802b is engaged with the mobile robot 50. The battery pack 802b can supply power to the mobile robot 50. For ease of illustration, the battery pack 802b is shown simplified in Figure 15 [the figure], but the battery pack 802b can be the same as the battery pack 802a. The power station 800 can include a connector 804, and the battery pack 802a can include a corresponding connector 806. The electrical connectors 802 and 804 can be configured to engage with each other to transfer electrical signals and / or power between corresponding electrical contacts on the connectors. The battery pack 802b can be electrically connected to the mobile robot 50 via the connectors 804 and 806 ( Figure 15 not shown in [the figure]) such that the battery pack 802b can supply power to operate the mobile robot 50, or such that the battery pack 802b can be charged by the mobile robot 50.

[0131] When the battery pack 802 is removed from the mobile robot 50, the power station 800 can be used to directly charge the battery pack 802a. The connector 804 of the power station 800 can be connected to the connector 806 of the battery pack 802a to transfer power and signals, as discussed herein. When the battery pack 802b is in the mobile robot 50, the power station 800 can also be used to charge the battery pack 802b. The connector 804 of the power station 800 can be connected to a corresponding connector 806 on a charger 100 (e.g., a docking station) to transfer power and signals as discussed herein. Power can be transferred from the power station 800 to the charger 100 via the connectors 804 and 806. As discussed herein, the power can then be transferred from the charger 100 to the mobile robot 50 via the first or upper contact 112 and the second or lower contact 114 on the charger 100 and the corresponding first or upper contact (e.g., teeth) 56 and second or lower contact (e.g., teeth) 58 on the mobile robot. The power can then be transferred from the mobile robot 50 to the battery pack 802b using connectors similar to the connectors 804 and 806. The power station 800 can charge the battery pack 802b by sending power via the charger 100 and the mobile robot 50 to reach the battery pack 802b. The power station 800 can use the same interface (e.g., the connector 804) to directly charge the battery pack 802a or to charge the battery pack 802a through the charger 100.

[0132] Power station 800 can receive a feedback signal, and power station 800 can use the feedback signal to identify the type of load. For example, power station 800 can be configured to identify any combination of the following: charging battery pack 802b through charger 100 (e.g., docking station), directly charging battery pack 802a, directly charging battery pack 802a when the battery pack fails or is fully discharged, and / or an unrecognized load. Power station 800 can monitor current and / or voltage to identify different types of loads, as described herein. As discussed here, power station 800 can operate differently when charging in these different environments. For example, when charging battery pack 802b through charger 100, power station 800 can monitor the temperature of charger 100, and when directly charging battery pack 802a, power station 800 can monitor the voltage from the battery cells. Power station 800 can use this information to determine when to provide charging power and when to prohibit charging, which can improve safety and efficiency.

[0133] Some chargers only provide a constant current or voltage such that charging power can be transferred whenever a load is electrically connected thereto. In contrast, some intelligent charging systems perform robust communication between the load and the charger (e.g., using wireless, Bluetooth, or other communication protocols). The intelligent charging system can transmit detailed information about the load status to the power source, detailed information about the power source status to the load, detailed information about the charging request, etc. In some embodiments, the systems disclosed herein can provide a limited transfer of information for load identification and monitoring without the cost and complexity of a more sophisticated intelligent charging system.

[0134] Figure 16An exemplary embodiment of connectors 804 and 806 is shown. Connector 804 may be a male connector and connector 806 may be a female connector, although the opposite configuration may be used, and various other types of connector configurations may be used. For example, the contacts may be conductive pins or corresponding conductive recesses. Connector 806 may have two power contacts 808a and 808b for transmitting bus power (e.g., for charging a battery pack). Connector 806 may have four auxiliary contacts 810, 812, 814, and 816. The auxiliary contacts may include two output contacts 810 and 812, which may be configured to output voltage signals to the power station 800. The auxiliary contacts may include two input contacts 814 and 816, which may be configured to receive an input voltage (e.g., separate from the main power transmitted through power contacts 808a and 808b). Connector 804 may have two power contacts 818a and 818b, and four auxiliary contacts 820, 822, 824, and 826, which may correspond to the contacts on connector 806. Connector 804 may have two input contacts 820 and 822, which may be configured to receive voltage signals from output contacts 810 and 812 of connector 806. Connector 804 may have two output contacts 824 and 826, which may output a voltage (e.g., separate from the main power transmitted through power contacts 818a and 818b). In some embodiments, the power station 100 may output a constant voltage (e.g., 24 volts, although other voltage values may be used) on each of output pins 824 and 826. In some embodiments, European Battery Connectors from Anderson Power Products may be used, although any suitable connector may be used.

[0135] The auxiliary contacts may be used to identify the type of load. For different types of loads, the amount of current drawn from the power station 800 through the auxiliary contacts and / or the voltage value sent to the power station 800 through the auxiliary contacts may be different. The power station 800 may monitor the amount of current drawn through auxiliary contacts 824 and 826 and / or the voltage values provided through auxiliary contacts 820 and 822. Since different values are generated depending on what connector 804 is plugged in, the power station 800 can identify the load.

[0136] When charging the battery pack 802b via the charger 100, the power station 800 can monitor the temperature of the charger 100. The charger 100 can have a temperature sensor 132 as described herein. In some cases, if the contacts 112 and 114 on the gasket become dirty, excessive heat will accumulate during charging. At least one voltage value provided as feedback to the power station 800 can indicate the temperature of the charger 100 (e.g., at one or both of the contacts 112 and 114). The power station 800 can use this feedback voltage to monitor the temperature of the charger 100. If the temperature exceeds the threshold temperature value, the power station 800 prohibits charging.

[0137] When directly charging the battery pack 802a, the power station 800 can monitor the voltage of the battery pack 802a. When the battery pack 802a is disconnected, the voltage of the battery pack 802a will stop being fed back to the power station 800. Responsively, the power station 800 can prohibit charging. When the battery pack 802b is being charged in the mobile robot 50, the voltage of the battery pack 802a is not fed back to the power station 800. For example, the mobile robot 50 can monitor the voltage of the battery pack 802b. If the battery pack 802b is removed such that the mobile robot 50 no longer sees the monitored voltage, the mobile robot 50 can prohibit charging.

[0138] During startup, the power station 800 determines the type of load, and this determination can control how the power station 800 monitors charging. The power station 800 can receive feedback signals (e.g., voltage signals through the auxiliary contacts on the connector 804), and the determined load type can affect how these feedback signals are interpreted (e.g., as signals indicating temperature or battery voltage).

[0139] The power station 800 can be configured to enable charging only when an acceptable load is identified. In some cases, the power station 800 can determine that an inappropriate load is connected and can prohibit charging responsively. In some cases, the connector 804 can be physically connected to other devices (such as forklifts or other machinery) not shown. The power station 800 can prevent charging power (which can be 6.2 kilowatts, although other values can also be used) from being transmitted to unintended devices. Figure 15 The power station 800 can perform two verification steps before enabling charging power. One verification can be based on the current drawn from the power station 800. The other verification can be based on feedback signals (e.g., voltage signals) sent back to the power station 800 from the attached device. If both verifications are met, the power station 800 can enable charging. If either verification fails, the power station 800 can prohibit charging, can provide an alarm or warning, and / or can request user input or a remedial action.

[0140]

[0141] ​Power station 800 may have a power source 830, which may supply power for the operation of power station 800 and be used to provide charging power for charging battery packs 802a and 802b. Power station 800 may include a current sensor 832, which may measure the current output through one of the auxiliary contacts of connector 804. Power station 800 may include a controller 834. Controller 834 may include one or more hardware processors, which may execute instructions stored in the memory. In some cases, controller 834 may include a dedicated processor with hardware designed to perform the functions of power station 800, as discussed herein. Power station 800 may include a user interface 836, which may receive input from the user and / or provide information output to the user. For example, user interface 836 may include a display, a speaker, a printer, etc. User interface 836 may include one or more buttons, dials, switches, or other user input elements.

[0142] Battery pack 802a may include a connector 806. One or more battery cells 838a and 838b may be coupled to connector 806 such that the battery 838 may be charged. Although two battery cells 838a and 838b are shown in Figure 15 , any suitable number of battery cells may be used, including a single battery cell. When connected, one of the auxiliary contacts of connector 806 may provide the voltage value (Vbatt) of the battery to power station 800. One of the auxiliary contacts of connector 806 may provide an intermediate battery voltage taken between the battery cells, which may be a center tap voltage (Vct).

[0143] Battery pack 802a may have a switch 840, which may be turned on (e.g., to a conducting configuration) to enable charging of battery cell 838, and which may be turned off (e.g., to a non-conducting state) to prevent charging of battery cell 838. Switch 840 may be a relay, a contactor, a solenoid, or any other suitable switching device. One of the auxiliary contacts of connector 806 may be coupled to a contactor or other switch 840 to provide current to operate switch 840. For example, when connected to power station 800, a 24-volt signal may be provided to switch 840, which may operate switch 840 and may cause current draw between connector 804 of power station 800 and connector 806 of battery pack 802a. Current sensor 832 of power station 800 may measure this current.

[0144] One of the auxiliary contacts of the connector 806 can be coupled to an additional electronic device 842 of the battery pack 802a, such as battery health monitoring, battery charge status monitoring, overcharge monitoring, etc. In some embodiments, the electronic device 842 can operate using power from the battery cells 838. The voltage provided to the electronic device 842 from the power station 800 (e.g., 24 volts) can enable the battery pack 802a to be charged after the battery pack has been substantially depleted. A failed, or discharged, or depleted battery can have a charge below a threshold minimum charge that would enable the battery to operate without external power. When the battery pack 802a is depleted, it can be restored, in part because the power station can transmit power (e.g., 24V) through the connectors 804 and 806 to operate the electronic device 842 of the battery pack 802a.

[0145] The charger 100 can include the connector 806. The controller 128 can operate the components of the charger 100 as discussed herein. The charger 100 can have a temperature sensor 132 that can provide a voltage signal indicative of the temperature of the charger 100 (e.g., at the upper contact 112 and / or the lower contact 114). The temperature voltage signal can be transmitted to the power station 800 through one of the auxiliary contacts of the connector 806 such that the power station 800 can monitor the temperature during charging. A voltage feedback signal representative of the sensed voltage (Vsens) provided to the mobile robot 50 can be generated and provided to the power station 800 through one of the auxiliary contacts of the connector 806. A voltage input signal (e.g., 24 volts) can be transmitted to the controller 128. The voltage input signal (e.g., 24 volts) can be used to operate one or more of the limit switch 120 (or momentary switch), the reed switch 124, the temperature sensor 132, or other components. The current drawn from the power station can pass through the auxiliary contact. The current sensor 832 of the power station can measure this current. In some embodiments, one of the voltage input signals (e.g., 24V) can be used to operate the temperature sensor 132, the limit switch 120, and the reed switch 124, while another voltage input signal (e.g., 24V) can be transmitted to the resistor 844. The resistor 844 can generate a current that can be measured by the current sensor 832 of the power station 800.

[0146] For current sensing during direct charging of the battery pack 802a, the power station current sensor 832 can sense the current used for the internal contactor or other switch 840. For charger current sensing, when the shroud is moved backward and the limit switch and the reed switch are enabled, the circuit can have a generally fixed current draw that can be different from the current draw of the battery pack 802a on the auxiliary pin. Thus, the circuit having the limit switch 120 and the reed switch 124, etc., sets the expected current draw on the auxiliary pin for charging through the charger 100.

[0147] In some embodiments, when directly charging the battery pack 802a, the current draw on the auxiliary pin is not operative. The battery pack can be configured to produce a different current draw than the current draw when charging through the charger 100 (e.g., docking station). For example, the charger can draw from about 50 to about 100 milliamps. If the current consumption measured by the current sensor 832 is within this range, the station 800 can determine that the load is being applied through the charger. When directly charging the battery, the range of current consumption can be from about 200 to about 1000 milliamps. Other values and ranges can be used.

[0148] The station 800 can receive two voltage feedback signals. When directly charging the battery pack 802a, the first voltage feedback value (Vct) can be within a first range (e.g., about 0 to 30 volts) and the second voltage feedback value (Vbatt) can be within a second range (e.g., about 30 to 60 volts). The second voltage feedback value is greater than the first voltage feedback value. This condition can be used by the station as an indication that the battery pack 802a is being directly charged.

[0149] When charging through the docking station, the voltage ranges can be flipped so that the first voltage feedback value can be within the second range (e.g., about 30 to 60 volts) and the second voltage feedback value can be within the first range (e.g., 0 to 30 volts). Any other voltage feedback ranges can be used. In some cases, the ranges do not overlap such that their values can be used to distinguish between directly charging the battery pack 802a and charging through the charger 100 (docking station).

[0150] To directly charge the battery pack 802a, one of the 24 - volt signals can be used to power the electronics 842 of the battery pack 802a instead of the electronics 842 using the battery pack 802a power, which can enable the station 8000 to power up a failed battery pack 802a. In some embodiments, the signal sent to the electronics 842 is not subjected to current sensing to measure it. Another 24 - volt signal can monitor the current. This 24 - volt signal can be directly connected to a solenoid or contactor 840 within the battery pack 802a, and the solenoid or contactor 840 can connect the battery cells 838 to the charging power.

[0151] To charge via charger 100 (e.g., docking station), the unmonitored 24 - volt output can be used to power electronic devices (e.g., reed switch 124, limit switch 120, temperature sensor, etc.) on the charger 100. Another 24 - volt output can be used to measure current and can be connected in series with a resistor 844 having a known resistance value, as well as reed switch 124 and limit switch 120. When reed switch 124 and limit switch 120 are triggered, a voltage signal (e.g., 24 volts) can pass through the known resistor to create a known current draw that can be measured (e.g., by power station 800).

[0152] Typically, when charging via charger 100 (e.g., docking station), current draw occurs before the power station 800 receives a feedback voltage signal. As the mobile robot 50 rolls up to the charger 100, there is current drawn from the power station 800. Then, when the mobile robot 50 docks with the charger 100, it will provide a feedback voltage signal. The power station 800 can be configured to enable charging when current draw occurs before the voltage value is fed back and to prohibit charging if they occur simultaneously. However, if the charger 100 station is turned on and the mobile robot 50 is already on the charger 100 station, current and voltage will occur simultaneously. In this case, the timing will not be as desired and the power station 800 will not be able to charge. If charging is desired, the mobile robot 50 can be configured to wait for a period of time. But if charging does not start within the specified amount of time, in response, the mobile robot 50 can be programmed to disengage from the charger 100 and re - engage to start charging.

[0153] As discussed herein, to charge a failed battery pack, the battery pack can draw current. But since battery cells 838 are failed, they do not provide a voltage feedback signal. When current check passes but no voltage returns, this can indicate that battery pack 802a is failed. But it has not been confirmed yet. Thus, the power station can be configured to have a user interface that prompts the user to indicate whether they have connected a battery before power is supplied.

[0154] Battery pack 802a can provide a feedback voltage signal from battery cells 838, for example. Alternatively, an input signal (e.g., 24V) can be used to generate a feedback voltage signal.

[0155] Figure 17It is a flowchart showing an exemplary embodiment of a method for charging a battery pack. At block 902, the power station 800 can output a current (e.g., on one of the auxiliary contacts of the connector). At block 904, the output current is measured. If the output current is within a first range (e.g., approximately 50 to 100 milliamperes), it can be an initial indication that the load can be charging the battery pack through the charger 100 (e.g., docking station). If the output current is within a second range (e.g., approximately 200 to 1000 milliamperes), this can be an initial indication that the load can be directly charging the battery pack. If the output current is some other value outside the expected first and second ranges, the process can proceed to block 905 to find the indeterminate load and prohibit charging.

[0156] At block 906, the method can check whether the voltage feedback value satisfies a first condition indicating that the load includes the charger 100 (e.g., docking station). In some cases, the first condition can be satisfied at block 906 when the first feedback voltage value is lower than the second feedback voltage value. Depending on how the battery pack 802a and the charger 100 are designed, various other conditions can be used. If the first condition is not satisfied at block 906, the method can proceed to block 908 to find the indeterminate load and prohibit charging. If the first condition is satisfied at block 906, the process can proceed to block 910 to confirm that the load is charging the battery pack 802b through the charger 100 (e.g., docking station). Since the measured current is within the first range and the feedback signal satisfies the first condition, the load determination is doubly verified. Then, the power station 800 can charge the battery pack 802b through the charger 100. In some cases, the power station 800 can monitor the temperature during charging. If the temperature does not exceed the threshold at block 912, charging is enabled and the temperature monitoring is repeated. If the temperature exceeds the threshold at block 912, the process moves to block 916 and prohibits charging.

[0157] At block 918, the method can check whether the voltage feedback value satisfies a second condition indicating that the load is directly charging the battery pack 802a. In some cases, the second condition can be satisfied at block 918 when the first feedback voltage value is higher than the second feedback voltage value. Depending on how the battery pack 802a and the charger 100 are designed, various other conditions can be used. If the second condition is satisfied at block 918, the process can proceed to block 920 to confirm that the load is directly charging the battery pack 802a. Since the measured current is within the second range and the feedback signal satisfies the second condition, the load determination is doubly verified. Then, the power station 800 can charge the battery pack 802a. In some cases, the power station 800 can monitor the battery voltage. If the battery voltage is detected at block 922, charging is enabled and the monitoring is repeated. If the battery voltage is not detected at block 922, the process moves to block 926 and prohibits charging.

[0158] If the second condition is not met at block 918, the method may proceed to block 930. If there is a feedback voltage, but it does not meet the second condition, the process moves to block 905 to find the indeterminate load and charging is prohibited. However, if there is no feedback voltage at block 930, this means that the reason the second condition was not met at block 918 may be that the battery pack is depleted. At block 932, a message is transmitted to the user via the user interface 836. The message can be whether the connected load is the issue of the battery pack. If the user provides a response that the battery pack is not connected, the process can move to block 905 to find the indeterminate load and charging is prohibited. However, if the user response is that the connected load is the battery pack 802a, the process can proceed to block 934, where it is determined that the load is a failed battery. The battery pack can be charged until it provides voltage feedback, and then the process can move to block 922 and continue as previously discussed.

[0159] Additional Considerations

[0160] The orientation terms used herein, such as "top", "bottom", "proximal", "distal", "longitudinal", "lateral", and "end", are used in the context of the examples shown. However, the present disclosure should not be limited to the orientations shown. In fact, other orientations are possible and within the scope of the present disclosure. The terms used herein that relate to circular shapes, such as diameter or radius, should be understood to not require a perfect circular structure, but rather should apply to any suitable structure having a cross-sectional area that can be measured from one side to the other. Terms generally relating to shapes, such as "circular", "cylindrical", "semicircular", or "semicylindrical" or any related or similar terms, do not require strict compliance with the mathematical definitions of circular or cylindrical or other structures, but may include structures that reasonably approximate the approximation.

[0161] Conditional language, such as "can", "could", "may", or "might", unless otherwise specifically stated or otherwise understood in the context in which it is used, generally is intended to express that certain examples include or do not include certain features, elements, and / or steps. Thus, such conditional language generally is not intended to imply that one or more examples in any way require features, elements, and / or steps.

[0162] Unless otherwise expressly stated, otherwise connecting language such as the phrase "at least one of X, Y, and Z" should be understood in context as generally being used to express that items, terms, etc. can be X, Y, or Z. Thus, such conjunctive language generally is not intended to imply that certain examples require the presence of at least one of X, at least one of Y, and at least one of Z.

[0163] As used herein, the terms "about," "approximately," and "substantially" refer to a quantity close to the stated quantity that still performs the desired function or achieves the desired result. For example, in some instances, as the context may dictate, the terms "about," "approximately," and "substantially" may refer to a quantity within 10% of the stated quantity. The term "generally" as used herein means predominantly including or tending towards a particular value, quantity, or characteristic of a value, quantity, or characteristic. As an example, in certain instances, as the context may dictate, the term "substantially parallel" may refer to something that deviates from exact parallelism by less than or equal to 20 degrees. All ranges include endpoints.

[0164] Several illustrative examples of mobile robots and charging interfaces have been disclosed. Although the present invention has been described in accordance with certain illustrative examples and uses, other examples and other uses (including examples and uses that do not provide all of the features and advantages set forth herein) are also within the scope of the present invention. Components, elements, features, acts, or steps may be arranged or performed differently from those described, and components, elements, features, acts, or steps may be combined, merged, added, or omitted in various examples. All possible combinations and sub - combinations of the elements and components described herein are intended to be included in this disclosure. No single feature or group of features is necessary or indispensable.

[0165] Certain features described in the context of separate implementations in this disclosure may also be implemented in combination in a single implementation. Conversely, the various features described in the context of a single implementation may also be implemented separately or in any suitable sub - combination in multiple implementations. Additionally, although features may be described above as acting in certain combinations, in some cases, one or more features from a claimed combination may be deleted from that combination, and the combination may be claimed as a sub - combination or a variant of a sub - combination.

[0166] Any part of any step, process, structure, and / or device disclosed or shown in one example of this disclosure may be combined with or used (or substituted for) any other part of any step, process, structure, and / or device disclosed or shown in a different example or flowchart. The examples described herein are not intended to be discrete and separate from one another. Combinations, variations, and some implementations of the disclosed features are within the scope of this disclosure.

[0167] Although operations may be depicted in a particular order in the drawings or described in the specification, such operations need not be performed in the particular order shown or sequentially, or all operations may be performed to achieve the desired result. Other operations not depicted or described may be incorporated into the example methods and processes. For example, one or more additional operations may be performed before, after, concurrently with, or between any of the recited operations. Additionally, in some implementations, the operations may be rearranged or reordered. Further, the separation of various components in the above-described implementations should not be construed as requiring such separation in all implementations, and it should be understood that the described components and systems may generally be integrated together in a single product or packaged into multiple products. Additionally, some implementations are within the scope of the present disclosure.

[0168] Moreover, although illustrative examples have been described, any examples with equivalent elements, modifications, omissions, and / or combinations are also within the scope of the present disclosure. Further, although certain aspects, advantages, and novel features have been described herein, not all such advantages may necessarily be achieved in accordance with any particular example. For example, some examples within the scope of the present disclosure achieve one advantage or a set of advantages as taught herein, without necessarily achieving other advantages taught or suggested herein. Additionally, some examples may achieve different advantages than those taught or suggested herein.

[0169] Some examples have been described in connection with the accompanying drawings. The drawings are drawn and / or shown to scale, but such scale should not be limiting since dimensions and proportions other than those shown are contemplated and within the scope of the disclosed invention. Distances, angles, etc. are merely illustrative and not necessarily in precise relationship to the actual dimensions and layout of the devices shown. Components may be added, removed, and / or repositioned. Further, the disclosure herein of any particular feature, aspect, method, characteristic, property, quality, attribute, element, etc. with respect to various examples may be used in all other examples set forth herein. Additionally, any method described herein may be practiced using any device suitable for performing the recited steps.

[0170] To summarize the present disclosure, certain aspects, advantages, and features of the invention have been described herein. Not all or any such advantages may necessarily be achieved in accordance with any particular example of the invention disclosed herein. No aspect of the present disclosure is necessary or indispensable. In many examples, the devices, systems, and methods may be configured differently than shown in the accompanying drawings or described herein. For example, the various functions provided by the illustrated modules may be combined, rearranged, added, or deleted. In some implementations, additional or different processors or modules may perform some or all of the functions described with reference to the examples described and shown in the accompanying drawings. Many implementation variations are possible. Any feature, structure, step, or process disclosed in this specification may be included in any example.

[0171] In summary, various examples of mobile robots and related methods have been disclosed. The present disclosure extends beyond the specifically disclosed examples to other alternative examples and / or other uses of the examples, as well as certain modifications and equivalents thereof. Additionally, the present disclosure expressly anticipates that various features and aspects of the disclosed examples may be combined with or substituted for one another. Accordingly, the scope of the present disclosure should not be limited by the specifically disclosed examples above, but should be determined only by a reasonable reading of the claims. In some embodiments, the drive system and / or support system disclosed herein may be used to move other devices or systems different from mobile robots.

Claims

1. A power station, the power station comprising: A power source; A connector, the connector comprising: At least one power contact for outputting power from the power source to charge a battery pack; A first auxiliary contact for transmitting current to a load; A second auxiliary contact for receiving a voltage signal from a charger or the battery pack; A current sensor for measuring the current transmitted via the first auxiliary contact; and A controller configured to determine, at least in part based on the measured current and the received voltage signal, that the load is: a) A battery pack electrically connected to a charger within a mobile robot, the charger being connected to the power station via the connector; or b) A battery pack directly connected to the power station via the connector.

2. The power station according to claim 1, wherein, The controller is configured to: Monitor the temperature of the charger via the voltage signal when the load is determined to be a battery pack electrically connected to the charger within the mobile robot; And Monitor the voltage of one or more battery cells of the battery pack via the voltage signal when the load is determined to be a battery pack directly connected to the power station.

3. The power station according to claim 2, wherein, The power station is configured to stop outputting power when the monitored temperature is higher than a threshold temperature.

4. The power station according to claim 2, wherein, The power station is configured to stop outputting power when the voltage signal monitoring the voltage of one or more battery cells indicates that the battery has been disconnected from the power station.

5. The power station according to claim 1, wherein, The connector comprises: A third auxiliary contact for transmitting another current to the load; and A fourth auxiliary contact for receiving another voltage signal.

6. The power station according to claim 5, wherein The current transmitted by the first auxiliary contact and the current transmitted by the third auxiliary contact have substantially the same voltage.

7. The power station according to claim 1, wherein, The power station is configured to transmit current to the load via the first auxiliary contact at a substantially constant voltage.

8. The power station according to claim 1, wherein, The controller is configured to: Determine that the battery pack within the mobile robot is electrically connected to the charger, the charger being connected to the power station via the connector, when the measured current is within a first current range and the received voltage signal is within a first voltage range; And Determine that the battery pack is directly connected to the power station via the connector when the measured current is within a second current range and the received voltage signal is within a second voltage range.

9. The power station according to claim 8, wherein, The controller is configured to determine that the load is a failed battery pack when the measured current is within the second current range and the received voltage signal is below a threshold voltage value.

10. The power station according to claim 1, wherein, The controller is configured to determine that the load is a failed battery pack at least in part based on the measured current and the received voltage signal.

11. The power station according to claim 1, the power station further comprising a battery pack, the battery pack comprising: One or more battery cells; A connector connected to the connector of the power station, wherein the connector of the battery pack comprises: At least one power contact for receiving power to charge the one or more battery cells; A first auxiliary contact, the first auxiliary contact being configured to receive current from the first auxiliary contact of a connector of the power station; and A second auxiliary contact, the second auxiliary contact being configured to transmit the voltage signal to a second auxiliary contact of a connector of the power station, wherein the second auxiliary contact is coupled to the one or more battery cells such that the voltage signal corresponds to the voltage of the one or more battery cells.

12. The power station according to claim 11, wherein, The battery pack includes a switch located between the at least one power contact and the one or more battery cells, wherein the switch has a non-conductive configuration that disconnects the at least one power contact from the one or more battery cells, and wherein the switch has a conductive configuration that electrically couples the at least one power contact to the one or more battery cells for charging.

13. The power station according to claim 12, wherein, The switch includes a contactor, a solenoid, or a relay.

14. The power station according to claim 12, wherein, The first auxiliary contact of the battery pack is configured to supply current to the switch to place the switch in the conductive configuration, enabling charging of the one or more battery cells.

15. The power station according to claim 14, wherein, The controller of the power station is configured to determine that the load is directly coupled to the battery pack of the power station when the measured current is within a current range, and wherein the amount of current provided to place the switch in the conductive configuration is within the current range.

16. The power station according to claim 11, wherein, The connector of the battery pack includes a third auxiliary contact for receiving another current, wherein the battery pack is configured to operate battery pack electronics from the another current such that the battery pack can be recharged when the one or more battery cells are fully discharged.

17. The power station according to claim 11, wherein, The connector of the battery pack includes a fourth auxiliary contact for providing another voltage signal, wherein the fourth auxiliary contact is coupled to the one or more battery cells such that the voltage signal corresponds to another voltage associated with the one or more battery cells.

18. The power station according to claim 1, the power station further including the charger, the charger including: A connector, the connector being coupled to the connector of the power station, wherein the connector of the charger includes: At least one power contact, the at least one power contact being configured to receive power transmitted to the mobile robot; A first auxiliary contact, the first auxiliary contact being configured to receive current from the first auxiliary contact of a connector of the power station; and A second auxiliary contact, the second auxiliary contact being configured to transmit the voltage signal to the second auxiliary contact of a connector of the power station.

19. The power station according to claim 18, wherein, The charger includes a docking station configured to receive the mobile robot.

20. The power station according to claim 18, wherein The charger includes a temperature sensor, and wherein the voltage signal indicates the temperature measured by the temperature sensor.

21. The power station according to claim 18, wherein, The charger includes a third auxiliary contact for receiving another current, wherein the charger is configured to use the another current to operate one or more sensors to detect whether the mobile robot is docked with the charger.

22. The power station according to claim 21, wherein, The charger is configured to use the another current to operate at least one momentary switch and / or at least one reed switch.

23. The power station according to claim 22, wherein, The first auxiliary contact is connected in series with a resistor and the at least one momentary switch and / or the at least one reed switch such that when the at least one momentary switch and / or the at least one reed switch is closed, a current is generated within a current range, and wherein the controller of the power station is configured to: when the measured current is within the current range, determine that the load is a battery pack electrically connected to the charger within the mobile robot.

24. The power station according to claim 18, wherein, The charger includes a fourth auxiliary contact for providing another voltage signal to the mobile robot indicative of a charging voltage provided by the charger.

25. The power station according to claim 18, further comprising the mobile robot docked with the charger, wherein, The mobile robot includes the battery pack.

26. The power station according to claim 25, wherein, The battery pack is removable.

27. The power station according to claim 25, wherein, The mobile robot is configured to monitor a battery voltage of the battery pack and, if the monitored battery voltage indicates that the battery pack has been removed, prohibit charging.

28. The power station according to claim 16, wherein, The current transmitted by the first auxiliary contact and another current transmitted by the third auxiliary contact have substantially the same voltage.

29. A method for charging a battery pack of a mobile robot, the method comprising the steps of: Transmitting a current from a power station through a first contact of a connector of the power station to a load; Measuring the current transmitted through the first contact; Receiving a voltage signal from a charger or a battery pack through a second contact of the connector; Determining the load based at least in part on the measured current and the received voltage to be: a) a battery pack electrically connected to a charger within a mobile robot, the charger being connected to the power station via the connector; or b) a battery pack directly connected to the power station via the connector; and Transmitting power from the power station through the connector to charge the battery pack.

30. The method according to claim 29, the method comprising the steps of: Determining that the load is a battery pack electrically connected to the charger within the mobile robot, the charger being connected to the power station via the connector.

31. The method according to claim 30, the method comprising the following steps: Measuring a temperature of the charger, wherein the voltage signal received through the second contact of the connector indicates the measured temperature.

32. The method according to claim 31, the method comprising the following steps: Prohibiting charging in response to determining that the measured temperature exceeds a threshold temperature.

33. The method according to claim 29, the method comprising the following steps: Determining that the load is a battery pack directly connected to the power station via the connector.

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