SYSTEM FOR SUPPORTING EMERGENCY OPERATION OF A VEHICLE AND A METHOD FOR THIS

Abstract

The present invention provides a system and a method for supporting the emergency operation of an electric vehicle. The system (100) comprises a main drive motor (106) for driving a first axle (402), an auxiliary drive motor (108) for driving a second axle (206) and for assisting the main drive motor (106) to propel the vehicle. The system (100) includes a steering assembly (110) with a steering assistance motor (112) configured to drive a steering pump (114) for steering a wheelset coupled to the second axle (206) to assist in steering the vehicle when the steering assembly (110) is operated by a user.The system (100) also includes a sensor arrangement (116) configured to detect a fault associated with the power steering motor (112) and a power steering arrangement (118) configured to couple the drive auxiliary motor (108) with the steering pump (114) when the fault associated with the power steering motor (112) is detected.

Description

TECHNICAL AREA

[0001] The present invention relates to motor vehicles. In particular, the present invention relates to a system for supporting emergency operation of a vehicle, such as in the event of a malfunction during steering, and to a method for doing so. BACKGROUND

[0002] Power steering systems assist the driver in steering a vehicle by utilizing a force source. They help the driver steer the vehicle by employing hydraulic or electric actuators to reduce steering effort. Hydraulic power steering assists the driver with a hydraulic cylinder, while electric power steering uses electric motors and a torque sensor to measure the steering effort. Electric systems can also use hydraulic mechanisms to move the steering wheel. Maintaining constant hydraulic fluid pressure is crucial for performance. A failure of the electric motor or its control unit can cause the power steering to stop working, posing a significant safety risk and potentially leading to serious accidents.For example, maintaining constant hydraulic fluid pressure is crucial for a rapid response, which is typically achieved by an electric motor-driven pump. If the electric motor or its control unit fails, the power steering system will cease to function, posing a significant risk, especially if the failure occurs during a steering maneuver. This can lead to serious accidents, injuries, and property damage. Therefore, damage to the electric motor within the power steering system is a critical factor that can render the vehicle undrivable and result in hazardous driving conditions.

[0003] Efforts have been made in the past to provide assistance to power steering systems in vehicles. For example, patent DE102012004040A1 describes an electromechanical power steering system with a first electric drive unit on the steering column and a second, redundant electric drive unit, also on the steering column, which provides additional assistance to the steering force. If the first drive unit fails, the second drive unit is activated. However, the use of two separate drive units in this system increases the overall cost of the vehicle and reduces the reliability of the power steering. Furthermore, installing the second electric drive unit alongside the first one compromises the vehicle's redundancy and availability.

[0004] There is therefore a need for a reliable solution that eliminates the disadvantages and limitations of conventional power steering systems for vehicles. Furthermore, the reliability of a vehicle's power steering system must be improved to prevent steering interruptions due to faults or malfunctions in the power steering motor. ITEMS OF THE PRESENT INVENTION

[0005] A general object of the present invention is to provide a system for supporting emergency operation, such as the steering, of an electric vehicle in the event of malfunctions of an electric motor, the power steering arrangement of the vehicle or its control unit, as well as a corresponding method.

[0006] One object of the present invention is to provide a system for using components on board an electric vehicle to assist the steering of the vehicle and to improve the safety of the occupants, particularly in the event of failure of the power steering motor or control unit.

[0007] Another object of the present invention is to improve the reliability and availability of a power steering system of a vehicle.

[0008] Another object of the present invention is to provide a method and a system for supporting a power steering arrangement of an electric vehicle that can be easily installed in existing electric vehicles. SUMMARY

[0009] Aspects of the present invention relate to a system and a method for supporting emergency operation of an electric vehicle by assisting the steering of the vehicle, even when faults or malfunctions are present in connection with an electric motor of the vehicle's power steering assembly. In one aspect, the system comprises a main drive train with a main drive motor configured to drive a first axle of the vehicle, an auxiliary drive train with a drive auxiliary motor configured to drive a second axle of the vehicle to assist the main drive motor in propelling the vehicle, and a steering assembly configured to enable steering of the vehicle in a left or right direction.The steering assembly comprises a power steering motor configured to drive a steering pump to steer a wheelset coupled to the second axle, thus assisting the user in steering the vehicle when operating the steering assembly. The system also includes a sensor assembly configured to detect a fault associated with the power steering motor, and a steering assist assembly configured to functionally couple the power steering motor to the steering pump when the sensor assembly detects a fault associated with the power steering motor.

[0010] In one embodiment, the steering arrangement can include a steering shaft connected to a steering wheel designed to allow a user to steer the vehicle, and a steering mechanism configured to steer the vehicle based on the rotation of the steering shaft. When the power steering motor is actuated, the steering pump can be configured to supply fluid to the steering mechanism to assist it in steering the vehicle.

[0011] In one embodiment, the steering assist arrangement can include a first clutch suitable for coupling the auxiliary drive motor to the second axle in an engaged position and for disengaging the auxiliary drive motor from the second axle in a disengaged position. The steering assist arrangement can also include a second clutch designed to couple the auxiliary drive motor to the steering pump in an engaged position and to disengage the auxiliary drive motor from the steering pump in a disengaged position.

[0012] In one embodiment, the system may include a control unit connected to the sensor assembly. The control unit may be configured to control the movement of the first clutch and the second clutch between the engaged and disengaged positions. The control unit may be configured to move the first clutch to the disengaged position and the second clutch to the engaged position when the sensor assembly detects the fault associated with the power steering motor.

[0013] In one embodiment, the control unit can be configured to control the actuation of the auxiliary drive motor when the second clutch is in the engaged position to couple the auxiliary drive motor to the steering pump so that the auxiliary drive motor can drive the steering mechanism.

[0014] In one embodiment, the sensor arrangement can be configured to detect the speed and torque of the auxiliary drive motor and an input shaft of the steering pump. The control unit can be configured to actuate the auxiliary drive motor such that the torque generated by the auxiliary drive motor substantially corresponds to the torque required for the input shaft of the steering pump, based on the output of the sensor arrangement, before the second clutch is moved into the engaged position.

[0015] Another aspect of the present invention relates to a method for assisting emergency steering of an electric vehicle. The method comprises the steps of driving a first axle of the vehicle by the auxiliary drive motor and assisting the auxiliary drive motor during forward or reverse movement of the vehicle. The method includes the step of steering the vehicle in a left or right direction by the steering assembly. The method also includes the step of detecting a fault associated with the steering assist motor by the sensor arrangement and assisting the steering of the vehicle by the steering assist arrangement through operational coupling of the auxiliary drive motor with the steering pump after the fault associated with the steering assist motor has been detected.

[0016] In one embodiment, the assisting step can include moving the first clutch of the power steering assembly between an engaged position and a disengaged position. In the engaged position of the first clutch, the auxiliary drive motor can be coupled to the second axle. In the disengaged position of the first clutch, the auxiliary drive motor can be disengaged from the second axle. The assisting step can also include moving the second clutch of the power steering assembly between an engaged position and a disengaged position. In the engaged position of the second clutch, the auxiliary drive motor can be coupled to the steering pump. In the disengaged position of the second clutch, the auxiliary drive motor can be disengaged from the steering pump.

[0017] In one embodiment, the method may also include the step of controlling the movement of both the first and second clutches between the engaged and disengaged positions by the control unit. The control step may involve moving the first clutch to the disengaged position and moving the second clutch to the engaged position when the fault associated with the power steering motor is detected. The control step may further include regulating the actuation of the drive auxiliary motor when the second clutch is in the engaged position, in order to couple the drive auxiliary motor to the steering pump. In one embodiment, the method includes detecting the speed and torque of the drive auxiliary motor and the input shaft of the steering pump.The control unit ensures that the auxiliary drive motor generates the required torque for the steering pump before engaging the second clutch.

[0018] Various objects, features, aspects and advantages of the invention will become clearer from the following detailed description of preferred embodiments together with the accompanying drawings, in which the same numbers represent the same components. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The accompanying drawings serve to further understand the present invention and are an integral part of this description. The drawings illustrate exemplary embodiments of the present invention and, together with the description, serve to explain the principles of the present invention. Fig. Figure 1 shows an exemplary schematic representation of a system for supporting emergency operation when steering an electric vehicle according to an embodiment of the present invention; Fig. Figure 2 shows an exemplary schematic representation of an auxiliary drive motor of a supporting drive train of the system, configured to assist the steering of the vehicle; Fig. Figure 3 shows an exemplary schematic representation of a control unit of the system; Fig. Figure 4A shows an exemplary schematic representation of the normal operation of a vehicle's power steering system; Fig. Figure 4B shows an exemplary schematic representation of the system-supported operation of the vehicle's power steering system; Fig. Figure 5 shows an exemplary flowchart illustrating a procedure for supporting emergency operation when steering an electric vehicle; and Fig. 6A and Fig. Figure 6B shows exemplary flowcharts illustrating different processes in a first configuration and a second configuration of the procedure for supporting the steering of the electric vehicle. DETAILED DESCRIPTION

[0020] The following section describes in detail embodiments of the invention as illustrated in the accompanying drawings. However, it is not intended to limit the foreseeable variations of embodiments with the necessary level of detail; on the contrary, the aim is to cover all modifications, equivalents, and alternatives that fall within the scope of the present inventions as defined by the accompanying claims.

[0021] The embodiments described here relate to a system and a method for improving the reliability of a power steering system in an electric vehicle, ensuring operation even in the event of faults or malfunctions of the electric motor or its control unit within the system. The system utilizes the vehicle's existing components to assist the power steering, eliminating the need for additional motors or actuators, thereby increasing the reliability and availability of the power steering system. Furthermore, the method and system of the present invention improve the safety of the vehicle occupants in the event of a failure of components of the power steering system.

[0022] Fig. Figure 1 shows an exemplary schematic representation of a system 100 for assisting the steering of an electric vehicle. The electric vehicle (here also referred to as the "vehicle") can include a battery electric vehicle (BEV), a plug-in hybrid electric vehicle (PHEV), a hybrid electric vehicle (HEV), and similar types. The system 100 comprises a main drivetrain 102 for driving the first axle of the vehicle and an assisting drivetrain 104 for assisting the main drivetrain 102 in driving the first axle. The assisting drivetrain 104 can drive a second axle of the vehicle to assist the main drivetrain 102 in moving the vehicle forward or backward, with the main drivetrain 102 driving the first axle and the assisting drivetrain 104 driving the second axle. The first axle can, for example, be the rear axle of the vehicle, while the second axle can be the front axle, or vice versa.In an exemplary embodiment, the supporting drivetrain 104 can function as an auxiliary drive for the main drivetrain 102, working in conjunction with the main drivetrain 102 to propel the vehicle with increased power in both directions. The supporting drivetrain 104 can also be engaged when the vehicle requires more aggressive braking. The main drivetrain 102 can include a main drive motor 106 designed to drive the first axle of the vehicle. The supporting drivetrain 104 can also include an auxiliary drive motor 108 that assists the main drive motor 106 in driving the first axle. Both the main drive motor 106 and the auxiliary drive motor 108 can be electric motors.

[0023] System 100 comprises a power steering assembly (hereinafter also referred to as the "steering assembly") 110 configured to enable the vehicle to be steered in a left or right direction. The power steering assembly 110 includes a steering assist motor 112 configured to drive a steering pump 114 to steer a wheel set of the vehicle coupled to the second axle, to assist in emergency operation while the vehicle is being steered when the steering assembly 110 is operated by a user. The steering assembly 100 may include a steering shaft connected to a steering wheel located in a cabin of the vehicle. The steering wheel may be adapted to allow a user to steer the vehicle by manually operating the steering wheel.The steering arrangement 110 can further include a steering mechanism configured to steer the vehicle based on the rotation of the steering shaft as a result of the user's steering wheel operation. The power steering motor 112 can be configured with the steering pump 114 such that, when the power steering motor 112 is actuated, the steering pump 114 can supply fluid to the steering mechanism to assist the steering mechanism when steering the vehicle. The power steering motor 112 can be configured to actuate automatically when the user / driver of the vehicle operates the steering wheel.

[0024] See Fig. Figure 2, which shows an exemplary representation of the auxiliary drive motor 108 of the assisting drive train 104, configured to assist the steering of the vehicle. The system 100 comprises a sensor assembly 116 connected to the power steering motor 112 and configured to detect a fault or malfunction related to the power steering motor 112. The sensor assembly 116 can also be configured to detect the rotational speed and torque of an output shaft 202 of the auxiliary drive motor 108 and an input shaft 204 of the power steering pump 114 of the power steering assembly 110. In an exemplary embodiment, the sensor assembly 116 can comprise one or more sensors selected from the group consisting of speed sensors, torque sensors, current sensors, voltage sensors, position sensors, temperature sensors, and the like.

[0025] The system also includes a steering assist assembly 118, configured to operationally couple the auxiliary drive motor 108 of the assisting drivetrain 104 to the steering pump 114 when the sensor assembly 116 detects the presence of a fault or malfunction in connection with the steering assist motor 112. The steering assist assembly 118 may include a first clutch 120, designed to couple the auxiliary drive motor 108 to the second axle 206 in an engaged position and to decouple the auxiliary drive motor 108 from the second axle in a disengaged position. The second axle 206 may be the front axle or the rear axle of the vehicle. In the engaged position of the first clutch 120, the auxiliary drive motor 108 drives the second axle 206 to provide additional power for improved propulsion or braking of the vehicle.In an exemplary embodiment, the first clutch 120, in its engaged position, can be designed to transmit the torque generated by the auxiliary drive motor 108 to the second axle 206 via any or a combination of a transmission and a differential arrangement, in order to enable effective torque distribution between the wheels mounted on the second axle 206. In the disengaged position of the first clutch 120, the auxiliary drive motor 108 is decoupled from the second axle 206, so that the auxiliary drive motor 108 can be coupled to the steering pump 114 to assist the steering of the vehicle.

[0026] The steering assistance arrangement 118 can also include a second clutch 122, which is designed to couple the auxiliary drive motor 108 to the steering pump 114 in an engaged position and to decouple the auxiliary drive motor 108 from the steering pump 114 in a disengaged position. In the disengaged position of the second clutch 122, the auxiliary drive motor 108 is decoupled from the steering pump 114, so that the auxiliary drive motor 108 can be operationally coupled to the second axle 206 to assist the vehicle's propulsion with improved performance. In the engaged position of the second clutch 122, the auxiliary drive motor 108 is coupled to the steering pump 114 to assist the vehicle's steering.

[0027] The system 100 may further comprise a control unit 124 connected to the sensor assembly 116. The control unit 124 may be configured to control the movement of the first clutch 120 and the second clutch 122 between the engaged and disengaged positions. The control unit 124 may be configured to move the first clutch 120 into the disengaged position to stop the supply of rotational force from the auxiliary drive motor 108 to the second axle 206, and to move the second clutch 122 into the engaged position to supply the rotational force from the auxiliary drive motor 108 to the input shaft 204 of the steering pump 114, when the sensor assembly 116 detects the presence of a fault or malfunction in connection with the power steering motor 112 or its electronic components.

[0028] In one exemplary embodiment, the control unit 124 can be implemented with various hardware configurations or a combination of software and hardware functions. It can include microcontrollers, switches, relays, gates, and specialized hardware functions such as application-specific integrated circuits (ASICs), electrically erasable programmable read-only memory (EEPROMs), or field-programmable gate arrays (FPGAs). Furthermore, memory components such as non-volatile random-access memory (RAM) or read-only memory (ROM) can also be part of the control unit 124. In another embodiment, the control unit 124 can be entirely software-based and operate either as part of an operating system or as an application running on it.

[0029] The control unit 124 can be connected to a torque sensor of the power steering assembly 110 to obtain information about the driver's steering input. The control unit 124 can be configured to determine, based on the output of the torque sensor of the power steering assembly 110, the speed and torque required from the output shaft 202 of the auxiliary drive motor 108 to ensure sufficient steering assistance.

[0030] The control unit 124 can be configured to control the actuation of the auxiliary drive motor 108 when the second clutch 122 is in its engaged position, in order to couple the auxiliary drive motor 108 with the steering pump 114 so that the auxiliary drive motor 108 can drive the steering mechanism of the steering assembly 110. Thus, the control unit 124 is configured to automatically switch the operation of the auxiliary drive motor 108 so that the steering pump 114 can perform its intended task of actuating the steering mechanism if the power steering motor 112 is faulty or malfunctioning.

[0031] The control unit 124 can be configured to actuate the auxiliary drive motor 108 such that the torque generated by the auxiliary drive motor 108 essentially corresponds to the torque required for the input shaft of the steering pump 114 based on the output of the sensor arrangement 116 before the second clutch 122 is moved into the engaged position. This prevents impermissible vibrations from being generated due to the difference between the torque generated by the auxiliary drive motor 108 and the torque required for the input shaft of the steering pump 114.

[0032] As in Fig. As shown in Figure 3, the control unit 124 can comprise a first control unit 302 connected to the auxiliary drive motor 108, a second control unit 304 connected to the power steering motor 112, and a third control unit 306 connected to the first and second control units 302 and 304. The first control unit 302 can also be configured to control the actuation of the auxiliary drive motor 108 and to regulate the movement of the first and second clutches 120 and 122 of the power steering assembly 118 between their respective engaged and disengaged positions.The sensor arrangement 116 can be connected to the first control unit 302 and the second control unit 304, allowing the sensor arrangement 116 to monitor the operating parameters of the second control unit 304 in order to determine an event related to a fault or malfunction of the power steering motor 112, and to transmit information regarding the speed and torque of the output shaft 202 of the auxiliary drive motor 108 and the input shaft 204 of the steering pump 114 to the third control unit 306. This enables the third control unit 306 to efficiently regulate the engagement and disengagement of the first and second clutches 120, 122 based on the output of the sensor arrangement 116.As a result, the first control unit 302 can automatically control the actuation of the first and second clutches 120, 122 to enable the auxiliary drive motor 108 to assist the steering of the vehicle if a fault or malfunction related to the steering support motor 112 is detected.

[0033] In an exemplary embodiment, the third control unit 306 can be connected to an electronic control unit (ECU) 308 of the vehicle and configured to control the ECU 308 to switch the vehicle into a "LIMP-HOME MODE" in which the vehicle's ignition switch is reset to prevent the supply of power to the vehicle's electrical systems. Additionally or alternatively, when the vehicle switches into "LIMP-HOME MODE," the vehicle's speed can be automatically reduced, and all non-essential functions of the vehicle can be switched off or operated at reduced power to prevent damage to the vehicle's occupants and components in the event of a fault or malfunction related to the power steering motor 112.The third control unit 306 can then inform the vehicle driver about the vehicle's "LIMP-HOME MODE" state by any or a combination of audiovisual notification, tactile warning, and haptic feedback. Based on input received from the driver, the third control unit 306 can then enable the first control unit 302 to disengage the first clutch 120 and engage the second clutch 122 to allow the supply of rotational force from the auxiliary drive motor 108 of the supporting drivetrain 104 to drive the steering pump 114 of the steering assembly 110.

[0034] The control unit 124 can include one or more input / output devices (I / O devices) 310, such as relays, connectors, keypads, touchscreens, wireless transmit / receive devices, server / console switches, etc., to receive input from the vehicle's driver regarding the selection of a desired option between a "Steering Assist Mode" and a "Stop Vehicle Mode." The control unit 124 can be configured to receive the input regarding the selection of the desired option wirelessly via the I / O devices 310. The control unit 124 can also be configured to communicate wirelessly with a portable device, such as a personal computer, laptop, mobile phone, smartwatch, and the like, connected to the user, such as the driver or a vehicle occupant, to receive the input.In one example, if the driver selects the “STEER-ASSIST MODE” option using the I / O device 310 of the control unit 124, the third control unit 306 can instruct the first control unit 302 to move the first clutch 120 into its disengaged position to stop the supply of rotational force from the auxiliary drive motor 108 to the second axle 206, and to move the second clutch 122 into its engaged position to supply the rotational force from the auxiliary drive motor 108 to the input shaft 204 of the steering pump 114, so that the auxiliary drive motor 108 can assist the steering of the vehicle if the power steering motor 112 malfunctions. However, if the driver selects the “STOP-VEHICLE MODE” option via the I / O device of control unit 124, the third control unit 306 can control the vehicle ECU so that the vehicle is stopped for repair or maintenance of the power steering motor 112.In one example, the I / O devices 310 can include a touch-sensitive display device in the vehicle cabin that allows the driver to make inputs regarding their desired selection. The I / O devices 310 can allow the driver to select options other than "STEERING ASSIST MODE" and "STOP VEHICLE MODE" based on the fault detected in the power steering motor 112.

[0035] Fig. Figure 4A shows an exemplary schematic representation of normal operation of the vehicle's power steering assembly 110, in which the power steering motor 112 drives the steering pump 114 to assist steering inputs made by the vehicle's driver. The main drive motor 106 of the main drive train 102 can drive the first axle 402 of the vehicle via a first differential assembly 404. The auxiliary drive motor 108 of the supporting drive train 104 can drive the second axle 206 of the vehicle via a second differential assembly 406, with the first clutch 120 of the power steering assembly 118 in the engaged position, or it can be disengaged, with the first clutch 120 in the disengaged position, depending on the driver's requirements.In this state of the auxiliary drive motor 108, the second clutch 122 of the power steering assembly 118 remains in its disengaged position to ensure that the torque of the auxiliary drive motor 108 is reserved for driving the second axle 206. When the power steering motor 112 is operating normally, i.e., when the sensor assembly 116 has not detected a fault or malfunction of the power steering motor 112, the control unit 124 holds the first clutch 120 and the second clutch 122 in their respective positions.

[0036] When the sensor arrangement 116 detects that the power steering motor 112 or its electronic components are faulty or malfunctioning, the control unit 124 moves the first clutch 120 into its disengaged position to stop the supply of torque from the auxiliary drive motor 108 to the second axle 206, and moves the second clutch 122 into its engaged position to mechanically couple the auxiliary drive motor 108 to the steering pump 114 and assist the vehicle's steering in the event of a failure of the power steering motor 112. In an exemplary embodiment, the control unit 124 may move the second clutch 122 into its engaged position only when the rotational speed or torque generated by the output shaft 202 of the auxiliary drive motor 108 is substantially equal to the operating speed or torque, respectively.The torque of the input shaft 204 of the steering pump 114 corresponds to the impermissible vibrations, wear and tear between the output shaft 202 of the auxiliary drive motor 108 and the input shaft 204 of the steering pump 114. The speed and torque generated by the output shaft 202 of the auxiliary drive motor 108, as well as the operating speed and torque of the input shaft 204 of the steering pump 114, are detected by the sensor arrangement 116.

[0037] Fig. Figure 5 shows an exemplary flowchart illustrating a method 500 for supporting emergency operation during the steering of an electric vehicle. The method 500 can be performed by the system 100 of the present invention. The method 500 comprises a step S502 in which the main drive motor 106 of the main drive train 102 drives the first axle 206 of the vehicle, and a step S504 in which the main drive motor 106 is assisted by the auxiliary drive motor 108 of the supporting drive train 104, which drives the second axle 402 of the vehicle, to drive the vehicle.

[0038] Method 500 comprises a step S506 in which the vehicle is steered in a left or right direction by the steering arrangement 110. Method 500 also comprises a step S508 in which the sensor arrangement 116 detects a fault associated with the power steering motor 112 of the power steering arrangement 110, and a step S510 in which the steering arrangement 118 assists the steering of the vehicle by operatively coupling the drive auxiliary motor 108 with a steering pump 114 of the power steering arrangement 110 after the fault associated with the power steering motor 112 has been detected. Step S510 may include moving the first clutch 120 of the steering arrangement 118 between an engaged position and a disengaged position. In the engaged position of the first clutch 120, the auxiliary drive motor 108 can be coupled to the first axle 402.In the disengaged position of the first clutch 120, the auxiliary drive motor 108 can be decoupled from the first axle 402. Step S510 can also include moving the second clutch 122 of the power steering assembly 118 between an engaged and a disengaged position. In the engaged position of the second clutch 122, the auxiliary drive motor 108 can be coupled to the steering pump 114. In the disengaged position of the second clutch 122, the auxiliary drive motor 108 can be decoupled from the steering pump 114.

[0039] Procedure 500 may also include a step S512 for controlling the movement of the first clutch 120 and the second clutch 122 between the engaged and disengaged positions by the control unit 124. Step S512 may involve moving the first clutch 120 to the disengaged position and moving the second clutch 122 to the engaged position after the fault associated with the power steering motor 112 has been detected. Step S512 may also include controlling the actuation of the drive auxiliary motor 108 when the second clutch 122 is in the engaged position, in order to couple the drive auxiliary motor 108 to the steering pump 114.

[0040] Step S508 of determining can include detecting the speed and torque of the output shaft 202 of the auxiliary drive motor 108 and the input shaft 204 of the steering pump 114 by the sensor arrangement 116. Step S512 of controlling can include actuating the auxiliary drive motor 108 such that the torque generated by the auxiliary drive motor 108 is substantially equal to the operating torque required for the input shaft 204 of the steering pump 114, based on the output signal of the sensor arrangement 116, before the second clutch 122 is moved into the engaged position.

[0041] System 100 and method 500 of the present invention improve the steering operation of the electric vehicle even in the event of faults or malfunctions of the electric motor of the vehicle's power steering system. Advantageously, system 100 and method 500 of the present invention increase the safety of the occupants in the event of a failure of the power steering motor or the associated electronic components.

[0042] Fig. Figure 6A shows an exemplary flowchart illustrating various operations in a first configuration of the procedure 500. Initially, the main drive motor 106 of the main drive train 102 drives the first axle 402 of the vehicle, and the auxiliary drive motor 108 of the supporting drive train 104 drives the second axle 206 of the vehicle. In block 602, the auxiliary drive motor 108 can be connected to the second differential assembly 406 via the first clutch 120, which is in its engaged position. At this stage, the power steering motor 112 supplies energy to the power steering pump 114, with the second clutch 122 in its disengaged position. The first control unit 302 of the control unit 124 can control the torque of the auxiliary drive motor 108, and the second control unit 304 of the control unit 124 can control the speed of the power steering motor 112.In block 604, the sensor assembly 116, connected to the second control unit 304, monitors the power steering motor 112 and its electronic components to diagnose or determine any associated faults or malfunctions. In block 606, the sensor assembly 116 checks whether the power steering motor 112 has a fault or malfunction and transmits the fault-related information to the third control unit 306. If the fault is detected in block 606, the procedure continues to block 608, where the third control unit 306 requests or instructs the first control unit 302 to activate the "Steering Assist Mode," in which the first control unit 302 stops the supply of rotational force from the drive auxiliary motor 108 to the second axle 206 and moves the first clutch 120 into its disengaged position.However, if no fault is detected in block 606, the procedure continues with block 604 for monitoring and diagnosing faults related to the power steering motor 112. After block 608, the procedure continues with block 610, where the first control unit 302 controls the speed and torque of the auxiliary drive motor 108 in order to match the speed and torque of the auxiliary drive motor 108 with an operating speed and torque of the input shaft 204 of the steering pump 114 based on the output of the steering assembly 116.After synchronizing the operating speeds of the output shaft 202 of the auxiliary drive motor 108 and the input shaft 204 of the steering pump 114, the process continues with block 612, in which the first control unit 302 moves the second clutch 122 into its engagement position to mechanically couple the auxiliary drive motor 108 with the steering pump 114 and generate the torque required for optimal operation of the steering pump 114. This allows the steering pump 114 to be operated by the auxiliary drive motor 108 in the event of a failure of the power steering motor 112.

[0043] Fig.Figure 6B shows an exemplary flowchart illustrating various processes involved in a second configuration of the method 500. In one exemplary embodiment, the second configuration of the method 500 begins with block 602 of the first configuration and proceeds similarly through blocks 604 and 606. When, in block 606, the sensor assembly 116 detects a fault associated with the power steering motor 112, the method proceeds to block 652, in which the third control unit 306 requests the vehicle ECU 308 to activate the "LIMP-HOME MODE," which resets the vehicle's ignition switch to prevent the supply of electrical current to the vehicle's electrical systems.When the vehicle is switched to "LIMP-HOME MODE," the vehicle's speed can be automatically reduced and all non-essential functions deactivated to prevent damage to the occupants and vehicle components in the event of a power steering motor failure. Subsequently, in block 654, the third control unit 306 can inform the vehicle's driver of the "LIMP-HOME MODE" status through any or a combination of audiovisual notification, tactile warning, and haptic feedback. Following this, the third control unit 306 can receive input from the vehicle's driver to select a desired option between "STEER-ASSIST MODE" and "STOP-VEHICLE MODE."Based on the driver's selection, the third control unit 306 can control the first control unit 302 to either continue with the assisted operation of the vehicle's power steering system or to stop the vehicle. In an exemplary embodiment, if the driver selects the "STEER-ASSIST MODE" option via the I / O devices 310 of the control unit 124, the procedure proceeds to block 656, where the third control unit 306 requests the first control unit 302 to stop the supply of rotational force from the auxiliary drive motor 108 to the second axle 206 and to move the first clutch 120 into its disengaged position.Following block 656, the procedure continues with block 658, where the first control unit 302 controls the speed and torque of the auxiliary drive motor 108 to match its speed and torque with the operating speed and torque of the input shaft 204 of the steering pump 114, based on the output of the steering assembly 116. After synchronizing the operating speeds of the output shaft 202 of the auxiliary drive motor 108 and the input shaft 204 of the steering pump 114, the procedure continues with block 660, in which the first control unit 302 moves the second clutch 122 into its engagement position to mechanically couple the auxiliary drive motor 108 to the steering pump 114 and generate the torque required for the optimal operation of the steering pump 114.This enables the control unit 124 to actuate the steering pump 114 even in the event of a failure of the power steering motor 112, thereby improving both the reliability and efficiency of the vehicle's power steering system during assisted operation. ADVANTAGES OF THE PRESENT INVENTION

[0044] The present invention provides a system to support emergency steering in electric vehicles and / or to improve the safety of the occupants in the event of failure of power steering components, e.g. in the event of malfunctions of the motor or the control unit.

[0045] The present invention provides a system for using components of an electric vehicle to assist the steering of the vehicle, particularly in the event of faults in an electric motor, the power steering arrangement of the vehicle or its control unit, and a corresponding method.

[0046] The present invention provides a system and a method for assisting the steering of an electric vehicle in order to improve the reliability and availability of the power steering arrangement. QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] DE 102012004040A1

[0003]

Claims

[1] System (100) for supporting emergency operation of a vehicle, wherein the system (100) comprises: a main drive train (102) with a main drive motor (106) configured to drive a first axle (402) of the vehicle; a supporting drive train (104) comprising an auxiliary drive motor (108) configured to drive a second axle (206) of the vehicle to assist the main drive motor (106) in propelling the vehicle; a steering arrangement (110) configured to enable the steering of the vehicle in a left or right direction, wherein the steering arrangement (Fault110) comprises a steering assistance motor (112) configured to drive a steering pump (114) to steer a wheel set coupled to the second axle (206) to assist the steering of the vehicle when the steering arrangement (110) is actuated by a user; a sensor arrangement (116) configured to detect a fault associated with the power steering motor (112); and a steering support arrangement (118) configured to operatively couple the drive support motor (108) with the steering pump (114) when the sensor arrangement (116) detects the fault associated with the steering support motor (112). [2] System (100) according to claim 1, wherein the steering arrangement (110) comprises: a steering shaft connected to a steering wheel, which a user can use to steer the vehicle; a steering mechanism configured to steer the vehicle based on the rotation of the steering shaft, wherein the steering pump (114) is configured, when the steering support motor (112) is actuated, to supply fluid to the steering mechanism to assist the steering mechanism in steering the vehicle. [3] System (100) according to claim 1, wherein the steering assistance arrangement (118) comprises: a first clutch (120) for coupling the auxiliary drive motor (108) to the second axle (206) in a engaged position and for disengaging the auxiliary drive motor (108) from the second axle (206) in a disengaged position; and a second clutch (122) for coupling the auxiliary drive motor (108) to the steering pump (114) in a engaged position and for disengaging the auxiliary drive motor (108) from the steering pump (114) in a disengaged position. [4] System (100) according to claim 3, comprising a control unit (124) connected to the arrangement (116) and configured to control the movement of the first clutch (120) and the second clutch (122) between the engaged position and the disengaged position, wherein the control unit (124) is configured to move the first clutch (120) into the disengaged position and move the second clutch (122) into the engaged position when the sensor arrangement (116) detects the fault associated with the power steering motor (112). [5] System (100) according to claim 4, wherein the control unit (124) is configured to control the actuation of the auxiliary drive motor (108) when the second clutch (122) is in the engagement position to couple the auxiliary drive motor (108) to the steering pump (114) so ​​that the auxiliary drive motor (108) can drive the steering mechanism. [6] System (100) according to claim 4, wherein: the sensor arrangement (116) is configured to detect the speed and torque of the auxiliary drive motor (108) and an input shaft (204) of the steering pump (114), and the control unit (124) is configured to actuate the auxiliary drive motor (108) such that the torque generated by the auxiliary drive motor (108) is essentially equal to the torque required for the output shaft (204) of the steering pump (114) based on the output of the sensor assembly (116) before the second clutch (122) is moved into the engaged position. [7] Method (500) for supporting emergency operation of a vehicle, wherein the method (500) comprises the following steps: Drive (S502) of a first axle (402) of the vehicle by a main drive train (102) with a main drive motor (106); Assisting (S504) the main drive motor (106) to propel the vehicle by means of an assisting drive train (104) with an auxiliary drive motor (108) that drives a second axle (206) of the vehicle; Steering (S506) of the vehicle in a left or right direction by means of a steering arrangement (110), wherein the steering arrangement (110) comprises a steering assistance motor (112) configured to drive a steering pump (114) to steer a wheel set coupled to the second axle (206) to assist the steering of the vehicle when the steering arrangement (110) is actuated by a user; Detecting (S508) a fault associated with the power steering motor (112) by means of the sensor arrangement (116); and Assisting (S510) the steering of the vehicle by means of a steering support arrangement (118) by operationally coupling the drive support motor (108) with the steering pump (114) when the fault associated with the steering support motor (112) is detected. [8] Method (500) according to claim 7, wherein the step (S510) comprises: Moving a first clutch (120) of the steering assistance arrangement (118) between an engaged position and a disengaged position, wherein in the engaged position of the first clutch (120) the auxiliary drive motor (108) is coupled to the second axle (206) and in the disengaged position of the first clutch (120) the auxiliary drive motor (108) is disengaged from the second axle (206); and Moving a second clutch (122) of the steering support arrangement (118) between an engaged position and a disengaged position, wherein in the engaged position of the second clutch (122) the auxiliary drive motor (108) is coupled to the steering pump (114) and in the disengaged position of the second clutch (122) the auxiliary drive motor (108) is decoupled from the steering pump (114). [9] Method (500) according to claim 8, comprising the step (S512) of controlling the movement of each of the first clutch (120) and the second clutch (122) between the engaged position and the disengaged position by a control unit (124) connected to the sensor arrangement (116), wherein the control step comprises: Moving the first clutch (120) into the disengaged position and moving the second clutch (122) into the engaged position when the fault associated with the power steering motor (112) is detected; and Control of the actuation of the auxiliary drive motor (108) when the second clutch (122) is in the engagement position in order to effectively couple the auxiliary drive motor (108) with the steering pump (114). [10] Method (500) according to claim 9, wherein: the step (S508) of determining includes detecting the speed and torque of the auxiliary drive motor (108) and an input shaft (204) of the steering pump (114), and The step (S512) of the control includes actuating the auxiliary drive motor (108) so that the torque generated by the auxiliary drive motor (108) is essentially equal to the torque required for the input shaft (204) of the steering pump (114) based on the output of the sensor arrangement (116) before the second clutch (122) is moved into the engaged position.

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