Method and apparatus for connecting connector of electric vehicle charger to socket of electric vehicle

Abstract

A device for connecting a connector of an electric vehicle charger to a socket of an electric vehicle, comprising: a securing member forming part of a securing world and / or a vehicle charger and / or an actuating mechanism; a non-stationary member for carrying the connector, the non-stationary member being movable relative to the stationary member along respective lines substantially parallel to each other by two of: an actuation displacement from a default position to an actuation position, and a superimposed compliant displacement from the actuation position to an actual position; at least one controllable actuator for effecting an actuation displacement; the compliance assembly is used for realizing compliance displacement; and a controller assembly for controlling the controllable actuator, determining the actual position, and / or determining a compliant displacement of the non-stationary member, and for taking an interventional action when the compliant displacement exceeds a first threshold value, the first threshold value being a non-linear function of the actuated position.

Description

Field of the Invention

[0001] The present invention relates to an apparatus and method for connecting a connector of an electric vehicle charger to a socket of an electric vehicle. Background of the Invention

[0003] The process of charging an electric vehicle generally requires manually connecting a cable charger to the socket of the vehicle.

[0004] In the last few years, several developments have been made by which an actuating mechanism, such as a robot, can be used to facilitate the support, movement, and connection of the charger to the socket of the electric vehicle. The actuating mechanisms currently known in the art are capable of locating the position of the socket of the electric vehicle and guiding and inserting the connector of the charger into the socket without operator intervention.

[0005] The actuating mechanism for charging an electric vehicle (also referred to herein as an "electric vehicle charging robot" or simply a "robot") generally includes many different components, such as actuators, compliance mechanisms, data capture devices, and a computer processor that controls the operation of all the peripheral devices of the robot. The computer processor can be connected via a communication device that allows the robot to be operated in response to certain data inputs.

[0006] Generally, a robot for charging an electric vehicle includes a housing, a protruding section actuated by an actuating device, and a portion that holds or integrates the charger and positions it into the socket of the vehicle. The process of inserting the connector into the socket of the electric vehicle includes different stages, depending on the specific characteristics of the robot and the vehicle. The process generally includes monitoring the position of the socket of the electric vehicle, positioning the robot closer to the socket of the electric vehicle, and inserting the connector into the socket, charging, and retracting the connector.

[0007] An electric vehicle charging robot may experience several disruptions before, during, and after connecting a charger to a vehicle's socket. Disruptions before connection may include the presence of people and unforeseen parts of the vehicle, where people can physically contact the robot through their own movement or the movement of the robot or an object along the robot's path, which may impede the robot's movement. When the connector is inserted into the socket (or even when the connector is closer to the socket), additional disruptions (such as passengers getting in and out of the vehicle, loading and unloading of luggage, external shocks, vibrations, or misalignment of the connector) may affect the process of inserting the connector into the socket, which may result in clamping or sometimes getting stuck in the socket.

[0008] The above-mentioned disruptions are generally adverse, and these disruptions can cause harm to people, objects, and the charging infrastructure (i.e., connectors, cables, robots, and chargers).

[0009] Brief description of the prior art

[0010] Certain solutions to the technical problems described herein have been described. Most solutions in the prior art rely on active control, i.e., software-based control, such as vision-based control that uses information collected from vision sensors to control the movement of the robot, or sensor-based control, whereby the processor obtains sensor information and adjusts the activities of the robot based on feedback. Other types of active control include software-based adjustment of the robot's actions when the compliance limit is exceeded, which depends on the force that the robot is designed to exert at a specific stage of the process (e.g., positioning and mating).

[0011] However, such technologies may be error-prone, rely on communication interfaces, and may not ensure that the robot responds quickly enough to disturbances (e.g., for some "real-time" implementations). In some cases, glitches during the autonomous charging of an electric vehicle using a robot may have serious consequences, such as causing significant harm to the operator of the charging station or damage to the vehicle and the surrounding infrastructure. Therefore, since the software for fully autonomous charging of EVs requires a high level of performance to obtain consistent and sufficient performance certification, these types of implementations are often very expensive and difficult to upgrade, which in turn may limit the use of autonomous charging solutions in many cases.

[0012] Other solutions aim to provide additional flexibility to the robot by introducing additional compliance mechanisms to mitigate any unpredictable effects. However, this approach may not fully solve the problem. For example, when the robot is positioned closer to the socket before starting the connection, the force exerted by the robot on the object through the connector it is using is usually low. To effectively complete the insertion of the connector into the socket, the robot must exert a certain force, which in most cases should be large enough to overcome the frictional force generated between the connector and the socket. Therefore, since the robot may exert different forces at different stages of the connection process, the actuation mechanisms known from the prior art may not fully solve this technical problem.

[0013] Document WO 2014015991 A2 describes a charging system and method for charging a motor vehicle, which includes a control system and a force determination sensor, wherein the controller communicates with the force detection device and actuates a robot-guided plug to a mating plug based on the plug connection force determined by the force detection device. If the force acting on the plug detected by the force detection device exceeds a threshold value (especially a predefined threshold value), the control system according to this document can interrupt or modify the plug movement. To achieve this predefined threshold value, the control device controls the robot such that the robot-guided plug is connected to the mating plug, or is configured especially by means of a program.

[0014] Other prior art documents describe methods for connecting connectors of EV vehicles, which include different stages, such as a positioning stage, a connection stage, and a charging stage, where different forces may be exerted on the external body, and thus different compliance threshold values are required. These prior art documents may still require predefined compliance intervention values determined by an electronic control system, which is loaded with software further executed by a processor of an electronic controller. The control system monitors any deviation from the intervention value, whereby compliance can be ignored or action can be taken on compliance. Therefore, these types of methods require pre-determining thresholds, which are monitored and acted upon by software means.

[0015] Therefore, for the autonomous charging of electric vehicles, there is still a need for improved, simplified, and reliable device systems and methods relying on hardware implementation, which can provide enhanced safety, implementation, and ease of use. Therefore, the object of the present invention is to provide a device and method for connecting a connector of an electric vehicle charger to a socket of an electric vehicle, which eliminates the disadvantages of the prior art. Summary of the Invention

[0017] The general object of the present invention is to overcome the above problems. More specifically, the present invention aims to provide an improved device (such as an actuating device) and method for connecting a connector of an electric vehicle charger to a socket of an electric vehicle, wherein the device includes a controller assembly that is capable of taking intervening actions when the device faces an interruption during the connection process. In addition, an object of the present invention is to provide a device and method that allow the controller assembly to take intervening actions based on the stage of the connection process. Preferably, the device and method of the present invention can be implemented by hardware and may not require a software-controlled controller to control its basic functions.

[0018] According to the present invention, this general object is achieved by a device that includes components for accomplishing and / or implementing actuating displacement and compliant displacement, and wherein the device is configured to take an intervening action when the compliant displacement exceeds a first threshold, which is a non-constant function of the actuating displacement. Brief Description of the Drawings

[0020] Figure 1a is a diagram of a device (1) according to the present disclosure. Figure 1b is a side view of a device according to an embodiment of the present invention. Figure 1c is a perspective elevated view of a device according to an embodiment of the present invention. Figure 1d is a perspective bottom view of a device according to an embodiment of the present invention.

[0021] Figures 2 - 9 is a side view showing an actuating device (1) with several displacements, positions, and thresholds according to the present invention.

[0022] Figure 10 - Figure 13a depicts the relationship between the threshold for triggering an intervening action and the actuating displacement / actuating position of a non-fixed member.

[0023] Detailed Description of the Present Invention

[0024] To avoid any harm to people and damage to objects and the infrastructure of the robot itself, it is desirable to provide a device (such as an actuating device) and method for autonomous charging of an electric vehicle that has a system that responds quickly and adequately to forces or pressures generated by interruptions that may occur during the entire charging process or steps before or after the charging process.

[0025] The present invention provides a device for connecting a connector of an electric vehicle charger to a socket of an electric vehicle. The device includes: a fixed member that forms part of a fixed world and / or the vehicle charger and / or an actuating mechanism; a non-fixed member for carrying the connector, which can move relative to the fixed member along corresponding lines that are substantially parallel to each other in two ways: an actuating displacement from a default position to an actuating position; and a superimposed compliant displacement from the actuating position to an actual position; at least one controllable actuator for achieving the actuating displacement; a compliance assembly for achieving the compliant displacement; a controller assembly for: controlling the controllable actuator; determining the actual position; and / or determining the compliant displacement of the non-fixed member; wherein the controller assembly is further configured to take an intervention action when the compliant displacement exceeds a first threshold; the first threshold is a non-constant function of the actuating position.

[0026] The present invention also describes a method for operating a device for connecting a connector of an electric vehicle charger to a socket of an electric vehicle. The device includes: a fixed member that forms part of a fixed world and / or the vehicle charger and / or an actuating mechanism; a non-fixed member for carrying the connector, which can move relative to the fixed member along corresponding lines that are substantially parallel to each other in two ways: an actuating displacement from a default position to an actuating position; and a superimposed compliant displacement from the actuating position to an actual position; at least one controllable actuator for achieving the actuating displacement; a compliance assembly for achieving the compliant displacement; the method includes the steps of: controlling the controllable actuator; determining the actual position; and determining the compliant displacement of the non-fixed member; characterized in that an intervention action is taken when the compliant displacement exceeds a first threshold; the first threshold is a non-constant function of the actuating position.

[0027] The device according to the present invention can also be referred to as an actuating device for connecting a connector of an electric vehicle charger to a socket of an electric vehicle. In the context of the present invention, the device according to the present invention can also be referred to as an "electric vehicle charging robot", or simply a "robot" for short. The actual vehicle charger can be connected to the connector via a cable and can be incorporated in or coupled or connected to the device according to the present invention.

[0028] Figure 1a A diagram showing a device (1) according to the present disclosure, which includes a connector (2) of an electric vehicle charger (3), a socket (4) of the vehicle, and the vehicle (5). Figure 1b and Figure 1c is a perspective view of the device according to an embodiment, and Figure 2is an illustration of the embodiment.

[0029] The device includes a fixed member (6) forming part of a stationary world, an electric vehicle charger, and / or an actuation mechanism. The fixed member (6) is a member that does not move relative to its support or the stationary world surrounding the device during normal use. The support can be interpreted as an actuation mechanism having at least one degree of freedom or at least two degrees of freedom or at least three degrees of freedom (such as one linear degree of freedom, two linear degrees of freedom, or three linear degrees of freedom). The fixed member may include a base plate, at least one joint point for coupling a compliance assembly or its elements or components. The fixed member may also include a fixed point for a controller assembly (12) or for any of its components. The fixed member (6) may also include a linear track for enabling a non-fixed member (7) to be displaced along a path.

[0030] The actuation device includes a non-fixed member (7) for carrying a connector for charging an electric vehicle and is substantially non-fixed relative to the fixed member and thus is also effectively non-fixed relative to the rest of the actuation mechanism (i.e., relative to the robot, relative to the environment or support, and / or relative to the stationary world). The non-fixed member is displaceable relative to the fixed member (6) along corresponding lines that are substantially parallel to each other by: the actuation displacement of at least one controllable actuator; and a compliant displacement or a superimposed compliant displacement caused, for example, by an external force. More specifically, the non-fixed member (7) can be displaced relative to the fixed member (6) along corresponding lines that are substantially parallel to each other in two ways by: an actuation displacement from a default position (8) to an actuated position facilitated by at least one controllable actuator; and a superimposed compliant displacement from the actuated position to an actual position. In particular, if the connector is attached to the actuation device or in the case where the connector is intended to be attached to the actuation device, these substantially parallel lines are substantially in the mating direction of the connector. The non-fixed member may include a base section, an effector plate, and a spindle nut. The base section is preferably fixed to the effector plate at a longitudinal position, and the effector plate can be configured to provide support for the connection of the electric vehicle charger and the base. The non-fixed member (7) may also provide support for the connection of the electric vehicle charger. The non-fixed member (7) can be configured to permanently hold the connector and / or be configured to engage and disengage the connector. The latter is particularly useful when the actuation device or the stationary world forming part of it and / or the vehicle charger and / or the actuation mechanism are configured to connect several connectors to different sockets and / or disconnect them from different sockets.

[0031] The actuating device includes at least one controllable actuator (11). Herein, the actuating displacement is defined as the displacement by means of the at least one controllable actuator, where the actuator (11) herein refers to an element capable of providing a driving force, preferably providing a driving force to a non-fixed member (7). Examples of controllable actuators can include motors, stepper motors, linear motors, electric motors, DC motors, AC motors, linear actuators, electric actuators, etc., but are not limited thereto. As used herein, the term "controllable" is used herein to imply that the actuator is configured to receive a signal and provide a driving force based on that signal. Preferably, the controllable actuator (11) further includes an actuator body (11a) and / or a spindle (11b) that can be supported by a spindle nut.

[0032] The compliant displacement is defined as the displacement typically caused by a force applied substantially along the direction permitted by the compliant assembly (13), preferably on the non-fixed member or on an element mechanically or compliantly connected to the non-fixed member. The force can be applied by a person or an object, which can have a fixed position or can be moving. The force can also be applied by a component of the device itself or an object that is a component of an actuating mechanism, the fixed world, etc. When the connector is already in the socket, vehicle movement can also cause compliant displacement. Such movement can occur because the vehicle is not stationary, or a person or object enters or leaves the vehicle. Inertial forces acting on the non-fixed member due to the acceleration / deceleration of a motor or mechanical device can actually also cause compliant displacement. However, these inertial forces are considered irrelevant to the present invention.

[0033] The actuating device (1) further includes a compliance assembly (13) for accomplishing, implementing, and / or facilitating compliant displacement. The compliance assembly includes at least one and more preferably at least two elastic or compliant elements, which are herein referred to as any element capable of providing a compliant response. The compliant element can have a stiffness, damping, or a combination thereof related to its function. In particular, typical components having related stiffness and / or damping are springs (helical springs, leaf springs, etc.), dampers, gas springs, valves (for pneumatic / hydraulic damping), etc.

[0034] The non-fixed member (7) is displaceable relative to the fixed member. Preferably, the non-fixed member is displaceable along respective lines (e.g., lines 7a, 7b) that are substantially parallel to each other for actuation displacement and / or for compliant displacement. The non-fixed member (7) is preferably displaceable relative to the fixed member (6) in two substantially opposite directions and thus relative to any element mechanically connected to the fixed member (6). The non-fixed member (7) may be mechanically coupled to the actuator (11) by non-compliant elements and / or by compliant elements. The actuator may be mechanically coupled to the non-fixed member and, for example, when the actuator is activated and applies a force on the non-fixed member, the non-fixed member may be displaced for actuation displacement via a mechanical means such as a spindle (11b). The controllable actuator (11) is preferably compliantly coupled to the fixed member by a compliant element and thus may be displaced compliantly by a force applied on the non-fixed member to which the actuator (11) is preferably mechanically (non-compliancy) coupled. The fixed member (7) may be compliantly coupled to the non-fixed member by a compliant element that allows compliant movement in at least one degree of freedom. The compliance assembly (13) may include at least one, or at least two, or at least three compliant elements.

[0035] The compliance assembly (13) may assist the actuation device in finding the socket of the electric vehicle, attenuate the impact between the connector and the socket, and allow the connector to move with the vehicle within certain limits once connected to the socket. The compliance assembly (13) may have a certain range of stiffness and, for this purpose, may include at least one compliant element having elastic force.

[0036] The first compliant element preferably compliantly couples the fixed member (6) to the actuator (11), the actuator body (11a), or their connection point, and, for example, when an external force is applied on the non-fixed member (7), the first compliant element displaces the actuator (11) compliantly in one degree of freedom. The first compliant element is preferably selected from compression compliant elements. The second compliant element compliantly couples the fixed member (6) to the actuator (11), the actuator body (11a), or their connection point, and, for example, when an external force is applied on the non-fixed member (7), the second compliant element displaces the actuator (11) compliantly in one degree of freedom. The second compliant element is preferably selected from extension compliant elements. The types of the first compliant element and the second compliant element, i.e., extension, compression, or other compliance types, are not mutually exclusive but may be interchangeable.

[0037] The non-fixed member (7) is capable of compliant displacement by the application of an external force or a "load event" applied to the actuating device (1) or to any element mechanically connected to the actuating device (1), such as a connector for charging an EV. The terms "external force" or "load event" shall be interpreted as a force applied to the non-fixed member or to any element mechanically connected to the non-fixed member that triggers a compliant response from the compliant assembly. Examples include forces applied by a person or an object along the path of the moving actuating device, such as a push force, and forces applied by a passenger getting on or off a vehicle, loading and unloading of luggage, external impacts on the vehicle, vibrations, and combinations thereof. The external forces applied to the actuating device or to any element mechanically connected thereto mainly refer to external forces applied in two directions substantially opposite to each other along an axis substantially parallel to the imaginary axis, for example, when a pulling force is applied to the actuating device.

[0038] The non-fixed member (7) is capable of displacement relative to the fixed member. Preferably, the non-fixed member is capable of displacement in an actuating displacement and / or in a compliant displacement along respective lines that are substantially parallel to each other. Thus, the non-fixed member can undergo different displacements, which can bring it to a position different from the actuating position. In the context of the present invention, the term displacement is intended to represent the movement or displacement of a body (such as the non-fixed member) along a path (such as a linear track (6d)).

[0039] According to the present invention, the default position (8) of the non-fixed member (7) is the position to which no external force or actuating displacement is applied. If there is no (or will not be) external force that enables a compliant displacement, the position of the non-fixed member (7) relative to the fixed member under the influence of the actuating displacement is referred to as the actuating position. When considering the influence of the external force that causes the compliant displacement, the position of the non-fixed member relative to the fixed member is defined as the actual position. Thus, the actual position can be the result of a compliant displacement superimposed on an actuating displacement that can be zero or greater than zero. In some cases, the actual position can be the result of a compliant displacement superimposed on an actuating displacement below zero.

[0040] The actuating device (1) includes a controller assembly (12) for: controlling a controllable actuator; determining the actual position of the non-fixed member; and / or determining the compliant displacement of the non-fixed member.

[0041] The controller assembly is further configured to take an intervention action when the compliant displacement exceeds a first threshold, which is a non-constant function of the actuating position.

[0042] The controller assembly (12) can be configured to control a controllable actuator; determine the actual position; and / or determine the compliant displacement of the non-fixed member.

[0043] As used herein, the term "component" is a broad term and shall be given its ordinary and customary meaning to a person of ordinary skill in the art, and is not limited to a special or customized meaning. Preferably, the term "component" includes a set of elements that are grouped under a basic function and can be in fluid communication with each other (e.g., via an electrical signal). The element parts of a component as used herein need not be mechanically coupled to each other.

[0044] The term "determine" (and its grammatical variants) encompasses a wide variety of actions and, when used herein, is a broad term and shall be given its ordinary and customary meaning to a person of ordinary skill in the art, and is not limited to a special or customized meaning.

[0045] As used herein, the term "determine the actual position" may specifically refer to (but is not limited to and preferably) sensing, detecting, monitoring, measuring, estimating, and / or calculating the actual position of the non-fixed member (7) and / or the force applied thereto.

[0046] As used herein, the term "determine the compliant displacement" may specifically refer to (but is not limited to and preferably) sensing, detecting, monitoring, measuring, estimating, and / or calculating the actual position (7) and / or the force applied thereto.

[0047] Preferably, the actual position and / or the compliance displacement are determined by at least one sensor. To this end, the controller assembly (12) may include one or more sensors (12a) selected from safety sensors, distance sensors, proximity sensors, positioning sensors, magnetic sensors, force sensors, or combinations thereof. For example, to determine the compliance displacement, the controller assembly (12) may include a first sensor, such as a proximity sensor. A proximity sensor according to the present disclosure may sense whether an object is within a sensing area in which the sensor is designed to operate. The proximity sensor may be configured to determine proximity and provide an output, such as a binary output. Additionally, the sensor may provide a position output to determine distance. Further, assuming that force can be used as a measure of the compliance displacement, the determination of the compliance displacement may be made by determining the force applied to the non-fixed member (7) via different mechanisms, but preferably by using a force sensor. The first sensor (12a) may be configured to determine when the non-fixed member is in a determined position near the sensor and change the output value when the object being measured (i.e., the non-fixed member) is in a certain position or nearby. Alternatively or additionally, the first sensor may be configured to continuously or discontinuously determine the distance between the sensor and the non-fixed member (7) and change the output value when the object being measured (i.e., the non-fixed member) is at a certain distance from the distance sensor. According to the principles of the present invention, more than one sensor may be used. The controller assembly (12) may also be capable of determining the actual position of the non-fixed member (7) and determining the compliance displacement by comparing the actual position with the actuation position. The control assembly may further be configured to determine the compliance displacement based on the measured force applied to the non-fixed member. Additionally, the sensor array may include two sensors, wherein the first sensor is configured to provide a signal or data representing the actual position of the non-fixed member and / or determining the proximity of the non-fixed member, and wherein the second sensor is configured to provide a signal or data representing the compliance displacement of the non-fixed member or the force applied to the non-fixed member in a direction substantially along the direction of the compliance displacement.

[0048] The controller assembly may include a controller configured to receive an input signal and send an output signal (preferably an electrical signal). The input signal may be the output of a sensor, and the output signal may be a signal sent to a controllable actuator. Preferably, the output signal may be an intervention action defined according to the present invention. The controller, which is part of the controller assembly, may be any device configured to send an intervention action based on the signals received by the sensors. The controller may be selected from safety relays.

[0049] The controller assembly may in a simple form include sensors and / or switches for providing signals and switches or (safety) relays for responding to signals. More complex embodiments may include using data from force sensors. The system may include rather simple and thus robust mechanical or electrical (electronic) components, but a microprocessor is not excluded.

[0050] Preferably, the actual position and / or the compliant displacement is determined by at least one sensor.

[0051] The controller assembly may also be configured to control the actuation displacement based on the determined or estimated position of the socket on the electric vehicle, and in particular to control the actuation displacement to move the connector to or out of such a socket of the electric vehicle. The actuation displacement can be controlled by sending a control signal to a dedicated controller for controlling the actuation displacement.

[0052] The controller assembly may be configured to take intervention actions. The actuation device of the present invention is vulnerable to interference, so it is desirable that the device can quickly respond to interference that may damage the robot itself, its operator and / or people around it, or the vehicle to which it attempts to connect the connector, or damage objects around the robot.

[0053] The intervention actions may include sending an output signal, such as an electrical signal, to a controllable actuator. More specifically, the intervention actions may include, for example, interrupting the movement of the actuation device during positioning, insertion or the connection phase; and making a new attempt to complete the insertion process and / or reposition the actuation device relative to the socket of the electric vehicle. Preferably, the intervention action includes interrupting the connection process by interrupting or stopping the actuation displacement of the non-fixed member carrying the connector.

[0054] Furthermore, the intervention actions may depend on the actuation displacement of the non-fixed member. The actuation displacement may be zero, greater than zero or less than zero, and the intervention actions may be adjusted accordingly. The intervention actions may include any one of the following: changing the actuation displacement or the actuation position of the non-fixed member; interrupting or stopping the actuation displacement or the actuation position of the non-fixed member; changing the speed or direction of the actuation displacement or the actuation position of the non-fixed member; moving the non-fixed member to (towards) a predetermined position; changing the control mode of the actuator, in particular changing the controller settings to control the force applied by the actuator, more particularly changing the controller settings to control following a tactile input (e.g., zero force control, damping control, etc.), generally changing the control mode of the actuator to allow backdriving motion (e.g., the user pushes the connector backward, and the actuation displacement follows the direction of the applied force); cutting off the power supply to the actuator; and any combination of the above.

[0055] The controller component (12), particularly the controller, can be configured to receive signals from at least one sensor and send a signal (preferably, a signal for an intervention action) when the compliance displacement exceeds a first threshold, which is a non-constant function of the actuation position. By taking the intervention action, the device according to the present invention provides increased safety and thus eliminates the disadvantages associated with the prior art. The range of allowable compliance displacement is a non-constant function of the actuation displacement, whereby when the compliance displacement exceeds the threshold allowed at the actuation displacement at which the non-fixed member is currently located, the controller can trigger an intervention action.

[0056] More specifically, when the compliance displacement exceeds a first threshold, which is a non-constant function of the actuation position, an intervention action can be triggered. In a non-limiting exemplary embodiment, function 1 (f1), function 2 (f2), function 3 (f3), and function 4 (f4) can be threshold functions. These functions can be constant, linearly increasing or decreasing, exponentially increasing or decreasing, logarithmically increasing or decreasing, smooth or non-smooth, or any other continuous function. The functions can depend on the actuation position, the actuation displacement, or their respective derivatives.

[0057] According to the present invention, function 1 (f1), function 2 (f2), or a combination thereof can represent the threshold of the thrust force (100) applied to the non-fixed member. Function 3 (f3), function 4 (f4), or a combination thereof can represent the threshold of the pulling force (130). These functions can be combined, whereby for function 1 and function 2, this type of discontinuous function can be observed.

[0058]

[0059] Where y can be the actuation position, the compliance displacement, or the force, and z is the design value. In a preferred embodiment, the combined function includes an increasing or decreasing function and a constant. In a more preferred embodiment, the combined function of function 1 and function 2 includes a function that linearly increases with the actuation position, which reaches a maximum value from a certain value of the actuation position through a constant function. The actuation displacement is generally positive, but in some cases, it can be a negative actuation displacement, i.e., whereby the actuator retracts further backward from the default position, as shown in FIG. 13b. According to the present invention, the first threshold is the threshold of the compliance displacement from the actuation position in the first direction, where the controller is further configured to take an intervention action when the compliance displacement exceeds a second threshold, where the second threshold is the threshold in the second direction opposite to the first direction, and the values of the first threshold and the second threshold are different from each other. That is, the first threshold relates to the thrust force or the positive compliance displacement, and the second threshold relates to the pulling force or the negative compliance displacement. The first threshold and / or the second threshold can be a function of the instantaneous speed of the occurrence of the actuation displacement and / or the compliance displacement.

[0060] These functions can be considered as force thresholds, but can be achieved by measuring force, by measuring compliant displacement, or a combination thereof.

[0061] According to the present invention, when describing the process for autonomous charging of an electric vehicle, different stages can be defined. The process can at least include a positioning stage, a connection stage, a charging stage, and a disconnection stage. Additionally, according to the operation of the actuating device (1), additional stages can be established, namely a neutral stage and an active stage, where said stages are not mutually exclusive with the positioning stage, the connection stage, the charging stage, and the disconnection stage. The neutral stage can refer to the stage in which the actuator does not apply an actuating displacement to the non-fixed member. As a non-limiting example, the neutral stage is the stage in which the robot positions the connector near the socket but does not yet expect to apply a significant force to complete the connection. In the neutral stage, the actuating displacement of the non-fixed member is generally low or preferably zero, since the actuating device can be positioned near the socket by an additional actuating mechanism. The active stage is the stage in which the controllable actuator (11) applies a displacement to the non-fixed member. As a non-limiting example, the active stage is the stage in which the actuating device (1) has positioned the connector near the socket of the EV and expects to apply a greater force to complete the connection. In the active stage, the actuating displacement is preferably greater than zero.

[0062] Figure 1b and Figure 1c Schematically shown is a device (1) for connecting a connector (2) of an electric vehicle charger (3) to a socket (4) of an electric vehicle EV (5), the device comprising a fixed member (6) forming part of a fixed world and / or the vehicle charger and / or the actuating mechanism; a non-fixed member (7) for carrying the connector, the non-fixed member (7) being movable relative to the fixed member along corresponding lines that are substantially parallel to each other by both: an actuating displacement from a default position (8) to an actuated position; and a superimposed compliant displacement from the actuated position (8) to an actual position; at least one controllable actuator (11) for effecting the actuating displacement; a compliance assembly (12) for effecting the compliant displacement; and a controller assembly. Figure 1b is a representation of the default position of the non-fixed member (7).

[0063] Figure 1c A front perspective view schematically shows the device (1) and two compliance elements (13a) and (13b). The fixed member (6) is compliantly coupled to the controllable actuator (11) or its body (11a) by a first compliance element (13a); a second compliance element 13b compliantly couples the fixed member 6 to the controllable actuator (11) or its body (11a). In this representation, the first compliance element and the second compliance element are a compression element and an extension element, respectively. Figure 1bIt shows that a controllable actuator (11) is mechanically coupled to a non-fixed member (7) via a main shaft (11b) to achieve an actuation displacement.

[0064] Figure 2 An embodiment of the present invention is shown, in which the fixed member (101) includes a front plate (113). Also shown are a linear track (114) as part of a control assembly, a sensor (111) for monitoring the actual position (107), and a sensor (112) for monitoring the compliant displacement (109).

[0065] Figure 2 A non-fixed member (102) is shown, which includes an actuator plate (123) through which a connector of an electric vehicle can be connected. Also shown are a linear guide (121) and a spindle nut (122), where the non-fixed member (102) moves along the linear track (114). Also shown is a controllable actuator, also referred to herein as an actuator assembly (103), which includes an actuator (131), a linear guide (132), a sensor plate (133) for being monitored by the sensor (112), and a main shaft (134). In this embodiment, the actuator (103) includes a stepper motor (131) having a main shaft (134) that drives the spindle nut (122). Other embodiments may utilize other actuators. The actuator (131) can achieve an actuation displacement (106), which can be considered as the distance between the spindle nut (122) and the actuator (131). Thus, this causes the non-fixed member (102) to be displaced. If there is no (or will not be) external force that achieves the compliant displacement (109), then under the influence of the actuation displacement (106), the position of the actuator plate (123) relative to the front plate (113) of the fixed member (101) is defined as the actuation position (108, as Figure 3 shown). Subsequently, when considering the influence of the external force that causes the compliant displacement (109), the position of the actuator plate (123) relative to the front plate (113) of the fixed member (101) is defined as the actual position (107).

[0066] In addition, as part of the compliance assembly, Figure 2 a tension spring (104) as a second compliance element with a substantially constant stiffness and a compression spring (105) as a first compliance element with a substantially constant stiffness are shown. Both springs can be installed with a certain pre-tension such that they remain under load within the allowed compliant displacement range.

[0067] Figure 3Shows the effect of the compliant displacement (109) caused by an external force (180) at the default position. The controller assembly, in particular the sensor (111) that monitors the actual position (107a), triggers the sensor (111) based on threshold function 1. The sensor (112) that monitors the compliant displacement provides a constant value of threshold function 2 (160) for the compliant displacement due to the thrust (and the resulting threshold for the thrust) and a constant value of threshold function 3 (170) for the pull force (and the resulting threshold for the pull force). The sensor (112) that monitors the compliant displacement (109) measures the proximity of the sensor plate (133). When the sensor plate (133) is not directly above the sensor (112), the sensor switches its output value. In Figure 3 In it, the sensor plate (133) monitored by the sensor (112) is positioned in front of it, so the output value is not changed and no action (such as an intervention action) is triggered.

[0068] Figure 4 Shows the actuation displacement (106a), the actual position (107b), and the actuation position (108a). Compared with the threshold (150) at the actuation displacement (106), the actuation position (108a) defines an increased value of the threshold (150a) of function 1. The sensor plate (133) monitored by the sensor (112) is positioned in front of it, so the output value is not changed and no action (such as an intervention action) is triggered.

[0069] Figure 5 Shows the effect of the external force (180a) at the threshold of function 1 at the actual position (107c). The sensor (111) monitors the actual position, which provides a threshold (150a) for the compliant displacement (109a) based on the thrust that linearly increases with the actuation displacement (106a) (and the resulting thrust threshold). When the external force (180a) causes a compliant displacement (109a) of the non-fixed member that is not greater than the threshold (150a), the sensor (111) does not change its output signal.

[0070] Figure 6 Shows the effect of the external force (180b) at the threshold (150a) of function 1 at the actuation position (108a). The sensor (111) monitors the actual position (107d), which provides a threshold (150a) for the compliant displacement (109b). The external force (180b) triggers the sensor (111), and the sensor (111) monitors whether the actual position (107d) exceeds the threshold (150a) of function 1.

[0071] Figure 7The actuating device (1) is shown when an actuating displacement (106b) occurs, which results in an actuating position (108b) of the non-fixed member. Assuming that the actuating displacement (106b) has increased the actuating position (108b), and since no external force is applied, the actual position (107e) is equal to the actuating position (108b), the value (150b) of threshold function 1 has increased by changing the actuating position (108b). The value (160) of threshold function 2 remains unchanged, and the value (150b) of threshold function 1 is now greater than the value (160) of function 2.

[0072] Figure 8 The external force (180c) at the threshold (160) of function 2 at the actuating position (108b) and the influence when a force (180c) is applied that causes a compliant displacement (109c) are shown. The sensor (111) monitors the actual position (107f) and provides a threshold (150b) for the compliant displacement (109c). The external force (180c) moves the sensor plate (133) out of the way of the sensor (112) that monitors function 2, causing the sensor (112) to change its output value.

[0073] Figure 9 The influence of an external force (180d), in particular a tensile force, is shown. The external force (180d) causes a compliant displacement (109d) and an actual position (107g). The external force (180d) causes the sensor plate (133) to move out of the way of the sensor (112) that monitors function 3, causing the sensor (112) to change its output value.

[0074] The relationship between the thresholds (150, 150a, 150b) of the compliant displacements and their respective threshold forces can depend (among other things) on the choice of compliant components. In one embodiment, the compliant elements exert forces based on their deflection, such as tension springs, compression springs, or combinations thereof. Their stiffness can be constant, but they can also be very flexible. Other embodiments can include compliant components that provide damping.

[0075] Figure 10a A graph is shown representing the relationship between the thresholds and four different functions (function 1, function 2, function 3, function 4). The combined function of function 1 and function 2 describes a function that increases linearly with the actuating position, which reaches a maximum value from a certain value of the actuating position through a constant function. The combined function of function 3 and function 4 describes a constant function that increases linearly with the actuating position from a certain value of the actuating position.

[0076] Figure 10bA graph showing the relationship between a threshold and three different functions (Function 1, Function 2, Function 3) is shown. The combined function of Function 1 and Function 2 describes a function that increases linearly with the actuation position, which reaches a maximum value from a certain value of the actuation position through a constant function. Function 3 is a constant function, that is, the threshold does not change according to the actuation position.

[0077] Figure 11a A graph showing the relationship between a threshold and two different functions (Function 1, Function 2) is shown. The combined function of Function 1 and Function 2 describes a function that increases linearly with the actuation position, which reaches a maximum value from a certain value of the actuation position through a constant function.

[0078] Figure 11b A graph showing the relationship between a threshold and two different functions (Function 1, Function 2) is shown. The combined function of Function 1 and Function 2 is a constant function that decreases linearly with the actuation position from a certain value of the actuation position.

[0079] Figure 12a A graph showing the relationship between a threshold and two different functions (Function 1, Function 2) is shown. The combined function of Function 1 and Function 2 describes a function that increases exponentially with the actuation position, which reaches a maximum value from a certain value of the actuation position through a constant function.

[0080] Figure 12b A graph showing the relationship between a threshold and two different functions (Function 1, Function 2) is shown. The combined function of Function 1 and Function 2 describes an increasing logarithmic function with the actuation position, which reaches a maximum value from a certain value of the actuation position through a constant function.

[0081] Figure 13a A graph showing the relationship between a threshold and two different functions (Function 1, Function 2) is shown. The combined function of Function 1 and Function 2 describes a constant function that increases gradually from a certain value of the actuation position.

[0082] The position sensor or proximity sensor may include those sensors using inductance, capacitance, laser distance, potentiometer or other technologies. The sensors in other embodiments may include force-based sensors using strain gauges, inductance, capacitance piezoelectric or other technologies.

[0083] Although the present invention has been described in connection with the presently considered most practical and preferred embodiments, it is to be understood that the invention is not limited to the disclosed embodiments. On the contrary, it is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims, and the scope of the appended claims will be given the broadest interpretation so as to cover all such modifications and equivalent structures as are permitted by law. Further, it should be understood that when the terms "preferable", "preferably" or "preferred" are used in the foregoing description, it indicates that the feature so described may be more desirable, nevertheless, it may not be essential, and any embodiment lacking the same feature may be considered within the scope of the present invention, which scope is defined by the claims that follow. In reading the claims, it is intended that when words such as "a", "an", "at least one" and "at least a portion" are used, there is no intention to limit the claim to only one item unless specifically stated to the contrary in the claim.

Claims

1. A device for connecting a connector of an electric vehicle charger to a socket of an electric vehicle, comprising: a fixed member; - the fixed member forms part of a fixed world and / or the vehicle charger and / or an actuating mechanism; a non-fixed member: - the non-fixed member is for carrying the connector; - the non-fixed member is displaceable relative to the fixed member along corresponding lines that are substantially parallel to each other by both: --i. an actuating displacement from a default position to an actuating position; and --ii. a superimposed compliant displacement from the actuating position to an actual position; at least one controllable actuator for effecting the actuating displacement; a compliance assembly for effecting the compliant displacement; a controller assembly, the controller assembly being configured to: - control the controllable actuator; - determine the actual position; and / or - determine the compliant displacement of the non-fixed member; characterized in that the controller assembly is further configured to take an intervention action when the compliant displacement exceeds a first threshold; the first threshold is a non-constant function of the actuating position.

2. The device according to claim 1, wherein the intervention action depends on the actuating displacement.

3. The device according to claim 1, wherein the intervention action comprises at least one of the following: changing the actuating displacement or the actuating position of the non-fixed member; stopping the actuating displacement or the actuating position of the non-fixed member; interrupting the actuating displacement or the actuating position of the non-fixed member; changing the speed or direction of the actuating displacement of the non-fixed member; displacing the non-fixed member towards (towards) a predetermined position; changing the control mode of the actuator, including changing controller settings to control the force exerted by the actuator and / or allowing reverse drive movement; cutting off the power supply to the actuator; and any combination of the above.

4. The device according to claim 1 or 2, wherein the controller assembly is further configured to determine the compliant displacement by comparing the actual position with the actuating position.

5. The device according to claim 1 or 2, wherein the controller assembly is further configured to determine the compliant displacement based on a measured force applied to the non-fixed member.

6. The device according to any one of the preceding claims, wherein the controller assembly is configured to control the actuating displacement based on a determined or estimated position of the socket on the electric vehicle, and in particular to control the actuating displacement to insert or remove the connector from the socket of the electric vehicle and to move towards and away from the socket of the electric vehicle.

7. The device according to any one of the preceding claims, wherein the actuating displacement is controlled by sending a control signal to a dedicated controller for controlling the actuating displacement.

8. The device according to any one of the preceding claims, wherein The first threshold is a threshold of the compliant displacement from the actuated position in a first direction, wherein the controller is further configured to take an intervention action when the compliant displacement exceeds a second threshold, wherein the second threshold is a threshold in a second direction opposite to the first direction, and wherein the values of the first threshold and the second threshold are different from each other.

9. The apparatus according to any one of the preceding claims, wherein, the first threshold and / or the second threshold is also a function of the instantaneous velocity at which the actuated displacement and / or the compliant displacement occur.

10. The apparatus according to any one of the preceding claims, comprising at least one sensor for determining the actual position of the non-fixed member and / or the compliant displacement.

11. The apparatus according to any one of the preceding claims, comprising at least one sensor or sensor array from the group consisting of: position sensors, distance sensors or proximity sensors; sensors using inductive, capacitive, laser ranging or potentiometer techniques; force-based sensors, in particular using strain gauges, inductance, capacitance or piezoelectric techniques to measure the position of the non-fixed member or the force applied to the non-fixed member; sensors classified as safety sensors; or any combination of these sensors, and in particular, the sensors are selected from safety sensors, proximity sensors, distance sensors or combinations thereof.

12. The apparatus according to claim 11, wherein, the controller assembly is configured to determine the compliant displacement of the non-fixed member based on data or signals generated by the at least one sensor.

13. The apparatus according to any one of claims 10, 11 or 12, wherein, the controller assembly includes a relay, in particular a safety-rated relay, which cuts off the power to the actuator, and wherein the relay is configured to be triggered by data or signals from the sensor or sensor array.

14. The apparatus according to any one of claims 10 to 13, wherein, the sensor array includes two sensors, wherein the first sensor is configured to provide a signal or data representing the actual position of the non-fixed member and / or to determine the proximity of the non-fixed member, and wherein the second sensor is configured to provide a signal or data representing the compliant displacement of the non-fixed member or the force applied to the non-fixed member in a direction substantially along the direction of the compliant displacement.

15. A method for operating an apparatus for connecting a connector of an electric vehicle charger to a socket of an electric vehicle, the apparatus comprising: a fixed member; - the fixed member forms part of a fixed world and / or the vehicle charger and / or an actuating mechanism; a non-fixed member: - the non-fixed member is for carrying the connector; - the non-fixed member is displaceable relative to the fixed member along corresponding lines that are substantially parallel to each other by both: --i. an actuated displacement from a default position to an actuated position; and --ii. a superimposed compliant displacement from the actuated position to an actual position; at least one controllable actuator for achieving the actuating displacement; a compliance component for achieving the compliant displacement; The method comprises the following steps: - controlling the controllable actuator; - determining the actual position; and - determining the compliant displacement of the non-fixed member; wherein an intervention action is taken when the compliant displacement exceeds a first threshold; the first threshold is a non-constant function of the actuating position.

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