Steering sensor system for a motor vehicle, steering system for a motor vehicle and method for detecting a steering parameter of a steering wheel or steering shaft of the steering system

Abstract

The invention relates to a steering sensor system for an electrically assisted steering system (1) in a motor vehicle and comprises one or more control units (15; 15A, 15B) and one or more sensor ICs (11, 12; 13, 14). A control unit (15, 15A) has a first data communication interface (SPC1 / Interface) and a first sensor IC (11) has a second data communication interface. The first and second data communication interfaces are galvanically connected to each other via a first physical data line. The first sensor IC (11) is configured to detect a steering parameter of a steering wheel of the steering system, wherein the steering parameter comprises a torque or a rotation angle of the steering wheel (2).The first sensor IC (11) has at least two first sensor dies (Trq1, Trq2) for generating at least dual measurements for the steering parameter, and the first sensor IC (11) is configured to encode the first measurements for the steering parameter generated at least dually by the first sensor dies (Trq1, Trq2) in a single first communication message (K1). The first sensor IC (11) and the control unit (15, 15A) are configured for data transfer of the single first communication message (K1) via a single physical data line (19).

Description

[0001] The underlying invention relates in particular to a steering sensor system for a motor vehicle, a steering system for a motor vehicle and a method for detecting a steering parameter of a steering wheel or a steering shaft of the steering system.

[0002] Steering sensor systems are commonly used in electrically assisted steering systems, such as power steering in motor vehicles. Steering sensor systems are also used in particular in so-called steer-by-wire steering systems in motor vehicles.

[0003] For electrically assisted steering, steering sensor systems typically detect torque and angle of rotation—i.e., steering parameters—of the steering wheel or an associated steering shaft of the steering system. This is achieved by directly or indirectly coupling torque and angle sensors to the steering wheel or steering shaft. Since the associated control units for processing the steering parameters are usually located remotely from the sensors, the corresponding measured values ​​are transmitted to the respective control unit via physical data lines, which are typically (galvanically) connected to the connection pins of the respective system components.

[0004] Since electric power steering systems in motor vehicles are subject to increased safety requirements (e.g., ASIL-D), the necessary steering parameters are typically acquired redundantly. For example, steering sensor systems usually have two or more sensors for measuring torque and angle of rotation. The measured values ​​from each sensor are transmitted to one or more control units via physical data lines.

[0005] A steering sensor system on a steering shaft is known, for example, from EP 2 983 962 B1. The steering sensor system is designed for redundant detection of torque and angle of rotation and comprises two torque sensors and two angle of rotation sensors, with the two torque sensors and the two angle of rotation sensors each being arranged on a common circuit board. For the transmission of sensor signals to a control unit, a signal line from one torque sensor is electrically connected to the signal line of one angle of rotation sensor, with the two electrically connected signal lines being connected to the control unit via a common data line.To transmit the sensor signals, the sensors connected via the common data line are addressed by respective signals, so that the signal of the rotation angle sensor or alternatively the torque sensor is transmitted to the control unit via the common data line.

[0006] The known steering sensor systems are still comparatively complex with regard to the implementation of data lines and data transmission.

[0007] The object of the invention is therefore to provide a steering sensor system for a motor vehicle that is simplified, particularly with regard to the implementation of data lines, connection pins, and data transmission. Furthermore, a steering system for a motor vehicle and a method for acquiring a steering parameter are to be provided with the same objective.

[0008] This task is solved by the features of the independent claims. Further details arise from the dependent claims and the following description.

[0009] According to one embodiment, a steering sensor system is provided for an electrically assisted steering system in a motor vehicle, or a steer-by-wire steering system in a motor vehicle. The steering sensor system comprises one or more control units and one or more sensor ICs (sensor-integrated circuits).

[0010] One or more control units has a first data communication interface, hereinafter referred to simply as "interface," for example in the form of a connector (pin). One or more sensor ICs has a second data communication interface (e.g., pin). The term "interface" will also be used hereinafter for the short form of "data communication interface."

[0011] The first and second interfaces are galvanically connected to each other via a first physical data line.

[0012] The first sensor IC is configured to detect a steering parameter of a steering wheel or a steering shaft of the steering system connected thereto (non-rotatably), wherein the steering parameter preferably comprises a torque or an angle of rotation of the steering wheel or steering shaft.

[0013] The first sensor IC comprises at least two sensor dies for the at least dual generation of measured values ​​for the steering parameter. The term "at least dual" specifically means that the respective sensor IC generates at least two, for example, two, four, or integer multiples of 2, measured values ​​for the respective steering parameter, where the number of measurement channels or sensor dies corresponds to the number of generated measured values. The measured values ​​can be generated essentially simultaneously. Hall sensors, for example, are suitable for measuring torque.

[0014] The first sensor IC is configured to encode the first measurement values ​​for the steering parameter, generated by the first measurement channels or sensor dies (at least dual), into a single initial communication message. In other words, the first sensor IC summarizes the measurement values ​​generated by at least two measurement channels / sensor dies and generates a single communication message that includes all, but at least two, of the measurement values ​​generated. The control unit can then transmit or retrieve these at least two measurement values, for example, via a single trigger signal to address the respective sensor IC, in a single data transfer step in which the entire initial communication message is transmitted.

[0015] In particular, the sensor IC can convert or encode the measured values ​​or corresponding measurement signals based on transmission via PWM, SENT, SPC, or SPI. The term "encode" used here should be understood to mean that the corresponding parts of the communication message, in which the measured values ​​are encoded from a data processing perspective, can be extracted (decoded) by the receiving control unit according to the respective protocol used. Thus, after extraction from the communication message, the control unit has corresponding values ​​for the steering parameter(s).

[0016] This advantageously simplifies the addressing and data transfer between the sensor IC and the control unit.

[0017] The first sensor IC and the control unit are designed for data transfer of the first communication message via a single physical data line (or signal line). This means, in particular, that only one physical data line and one communication message are required to transmit two or more measured values. This simplifies the physical routing between the respective sensor IC and control unit and also reduces the number of interfaces (connections, pins) required. Furthermore, the retrieval of redundant measured values ​​for a steering parameter and the associated data transfer to the control unit can be simplified.

[0018] Overall, this results in a simplified implementation, while simultaneously ensuring the redundancy in the acquisition of steering parameters that is usually required for steering sensor systems.

[0019] In one embodiment, a second sensor IC (or ICs) can be provided, configured to also detect the steering parameter detected by the first sensor IC. For example, if the first sensor IC is configured to detect torque, then the second sensor IC is also configured to detect torque. The same applies to the angle of rotation.

[0020] The second sensor IC, analogous to the first sensor IC, comprises at least two secondary measurement channels or sensor dies for the at least dual generation of measured values ​​for the steering parameter (torque or speed). The second sensor IC is configured to encode the secondary measured values ​​for the steering parameter, generated at least dually by the second measurement channels / sensor dies of the second sensor IC, into a single secondary communication message. The steering parameter can advantageously be determined redundantly, and in particular multiply redundantly, using a suitable steering sensor system.

[0021] According to this embodiment, in a first alternative, the second sensor IC and the control unit can be configured for data transfer of the individual second communication message between the second sensor IC and the control unit via a single second physical data line between a further second data communication interface of the second sensor IC and a further first data communication interface of the first sensor IC. Measured values ​​from the second sensor IC are also transmitted to the control unit. Preferably, in this alternative, all measured values ​​from the sensor ICs are transmitted to the (same) control unit. For example, determined torque and angle measurements can be transmitted to a common control unit.From a data transmission perspective, the second physical data line can at least partially coincide with the first physical data line if, for example, pins of both sensor ICs are connected to the same data line. In this case, the second data communication interface can coincide with the second data communication interface, with the control unit's data communication interface then being connected to the data line. Reading or retrieving the measured values ​​can then be done via the same data line.

[0022] In a second alternative configuration, the steering sensor system can comprise two control units. The two (or more) sensor ICs and the two control units can be configured for data transfer of the communication messages generated as described above between the sensor ICs and the two control units via one or more physical data lines between a data communication interface of the two sensor ICs and a data communication interface of the two control units. Providing two control units can be advantageous, for example, with regard to redundancy and system safety. In particular, this alternative can provide for one sensor IC to transmit corresponding measured values ​​(e.g., torque) to one of the control units, and the other sensor IC to transmit corresponding measured values ​​(e.g., torque) to the other control unit.

[0023] In an embodiment with (only) one control unit, the first sensor IC can be configured to detect torque as a steering parameter, and two of the sensor ICs can be configured to detect the angle of rotation as a steering parameter. In some embodiments, the number of sensor ICs for detecting the angle of rotation and also the torque can be an integer multiple of 2. The sensor ICs for detecting the angle of rotation are configured to generate an additional communication message encoding the angle of rotation for data transfer to the control unit via a separate physical data line. With such an embodiment, torque and angle of rotation can be detected, particularly redundantly. Such systems are also known as TAS (Torque and Angle Sensor Unit).Such a steering sensor system offers the particular advantage of simplified implementation with regard to design, number of connections (pins), and data transmission. If only one control unit is present, the additional physical data line can at least partially coincide with the other data lines, analogous to the description above.

[0024] In certain embodiments, two control units are provided, wherein the first sensor IC, and preferably a second sensor IC, are configured to detect the torque as a steering parameter, and wherein furthermore, two sensor ICs are provided which are configured to detect the angle of rotation as a steering parameter and to generate an additional communication message encoding the angle of rotation for data transfer via a respective additional physical data line to one of the two control units. In particular, it can be provided that communication messages from a sensor IC for measuring torque are transmitted to the control unit to which the additional communication message(s) concerning the angle of rotation are transmitted. If two sensor ICs for measuring torque are present, communication messages from the second sensor IC concerning torque can be transmitted to the other control unit.

[0025] In some configurations, only one (single) control unit is provided, and two sensor ICs are used for measuring torque on the one hand and angle of rotation on the other. The sensor ICs are connected to the (single) control unit, as described herein, for data transfer and the transmission of communication messages.

[0026] In some embodiments, two (in particular exactly two) control units may be provided, and two sensor ICs each are available for detecting the torque on the one hand and the angle of rotation on the other. The two sensor ICs for detecting the angle of rotation and one of the sensor ICs for detecting the torque can be connected to one of the control units, as described herein, for data transfer and transmission of communication messages. The (remaining) sensor IC for determining the torque can be connected to the other of the two control units for data transfer and transmission of corresponding communication messages.

[0027] The terms "first," "second," etc., used herein are intended to distinguish between the respective components and do not necessarily indicate the number of components. For example, in one embodiment, a first sensor IC may be used to measure torque and a third sensor IC to measure the angle of rotation. In this case, despite the terms "first" and "third," there are only two sensor ICs, with the terms "first" and "third" distinguishing the sensor ICs "only" with regard to their function.

[0028] In an advantageous embodiment, the data transfer between a respective control unit and a respective sensor IC is based on one of the following digital data communication protocols: PWM (pulse width modulated data communication code), SENT (single edge nibble transition code), SPC (short pulse width modulated code), and SPI (Serial Peripheral Interface). In particular, unidirectional protocols can be used in certain embodiments. The aforementioned protocols are especially advantageous for transmitting the communication messages described herein, each of which encodes multiple measured values.

[0029] In certain configurations, the one or more control units each form a main control unit (MCU), which, in particular, each forms part of a higher-level electronic control unit (ECU). In certain configurations, the electronic control unit (ECU) may further include at least one so-called session border controller for controlling and monitoring data communication between the steering sensor system and other network components of the vehicle, and / or a low-dropout voltage regulator.

[0030] According to the embodiments described herein, a steering system for a motor vehicle is provided. The steering system is designed as an electrically assisted steering system or as a steer-by-wire steering system and comprises a steering wheel and an associated steering shaft, as well as a steering sensor system according to one of the embodiments described herein. The one or more sensor ICs are directly or indirectly coupled to the steering wheel or steering shaft for the purpose of detecting the torque and / or the angle of rotation as steering parameters. Advantages and beneficial effects of the steering system result directly from the advantages and beneficial effects of corresponding embodiments of the steering sensor system.

[0031] According to the embodiments, a method is provided for detecting a steering parameter of a steering wheel or a steering shaft (non-rotatably) connected thereto in a steering system designed according to the preceding embodiment. In particular, the method is provided in embodiments for detecting a steering parameter (torque and / or angle of rotation) with a steering sensor system according to one of the embodiments proposed herein.

[0032] According to the method, the steering parameter comprises a torque or a rotation angle. Depending on the type of sensor IC(s), either the torque or the rotation angle, or both steering parameters, can be determined, particularly redundantly or with multiple redundancies. For example, configurations can include at least one, preferably two, sensor ICs configured as torque sensors, as well as at least one, preferably two, sensor ICs configured as rotation angle sensors.

[0033] The process includes the following steps: - Acquisition of the steering parameter by a first of one or more sensor ICs, which includes at least two first measurement channels or sensor dies, wherein the acquisition of the steering parameter includes at least dual generation of measured values ​​for the steering parameter by the at least two first measurement channels or sensor dies of the first sensor IC, - Encoding the measured values ​​by the first sensor IC into a single or only first communication message and providing the first communication message by the first sensor IC for data transfer to the control unit, and - Transmission of the first communication message encoding the measured values ​​to a first data communication interface (e.g., pin) of the control unit from a second data communication interface (e.g., pin) of the first sensor IC via a single first physical data line, which galvanically connects the first and second data communication interfaces for the purpose of data transfer.

[0034] Following a procedurally appropriate design, the following may also be provided: - Acquisition of the steering parameter detected by the first sensor IC, for example, the torque or the angle of rotation, further by a second of the one or more sensor ICs, which comprises at least two second measurement channels or sensor dies for the at least dual generation of measured values ​​for the steering parameter, wherein the acquisition by the second sensor IC comprises the at least dual generation of second measured values ​​for the steering parameter by the at least two second measurement channels or sensor dies. This means that the respective steering parameter is acquired by two sensor ICs. - The second sensor IC encodes the measured values ​​into a single second communication message and makes this second communication message available for data transfer. This means that the second sensor IC encodes its measured values, analogous to the first sensor IC, into a communication message that can be used to transmit the measured values ​​to or retrieve them from a control unit in a data transmission operation.

[0035] The procedure according to the above design may further include: - Transmission of the second communication message encoding the measured values ​​to the control unit, specifically to a further second data communication interface of the control unit, from a further first data communication interface of the second sensor IC via a single second physical data line, which galvanically connects the first and second data communication interfaces for the purpose of data transfer. Analogous to the above, the second physical data line can at least partially coincide with the first physical data line, and the further second data communication interface can coincide with the second data communication interface. or - Transmission of the second communication message encoding the measured values ​​to another second data communication interface of another, second control unit from another first data communication interface of the second sensor IC via a single second physical data line, which galvanically connects the first and second data communication interfaces for the purpose of data transfer.

[0036] In particular, the method according to the above can, in its various embodiments, provide that communication messages from the sensor ICs are transmitted to a (common) control unit, or that communication messages are transmitted to different control units. For example, it is possible that communication messages from one sensor IC for dual torque determination and communication messages from two sensor ICs for determining the angle of rotation are transmitted to a first control unit, and communication messages from another sensor IC for dual torque determination are transmitted to a second control unit.

[0037] In certain configurations of the method and the steering sensor system, the various communication messages can be transmitted, at least partially, via the same physical data lines, although in this case, transmission can occur with a time delay. In this case, the first and second data lines, and possibly the third data line, can be at least partially or section by section identical. This can further simplify the implementation of the data lines.

[0038] According to a procedural design, it may be provided that the procedure further includes at least one of the following features: - Torque is detected by the first sensor IC, preferably also by the second sensor IC; the angle of rotation is detected as a steering parameter by a third sensor IC, preferably by two or more (e.g., natural multiples of 2) third sensor ICs of the one or more sensor ICs; at least one additional communication message encoding the angle of rotation is generated and provided for data transfer; and the at least one additional communication message is transmitted via a separate physical data line to one of the one or more control units. Thus, torque and angle of rotation can be detected and provided with simplified routing and transmission. In certain embodiments, it is possible for the additional data line to at least partially coincide with the first and / or second data line. - Transmitting the (first, second and / or additional) communication message(s) based on one of the following data communication protocols: PWM, SENT, SPC, SPI.

[0039] The advantages and beneficial effects of the procedural designs result analogously to the advantages and effects of the designs of the steering sensor system.

[0040] Exemplary embodiments of the invention are described in more detail below with reference to the attached figures. These show: Fig. 1. Schematic representation of a steering system of a motor vehicle, Fig. 2 a first exemplary implementation of a steering sensor system for a motor vehicle, Fig. 3 a second exemplary implementation of a steering sensor system for a motor vehicle, and Fig. 4 a schematic procedure.

[0041] Fig. Figure 1 schematically shows a steering system 1 for a motor vehicle (not shown). The steering system 1, which may be an electrically assisted steering system, comprises a steering wheel 2 and a steering shaft 3 connected to it. The steering system 1 further comprises a steering sensor system 4, which may, for example, be arranged in the area of ​​a hub of the steering wheel 2 in conjunction with the steering shaft 3. In the present embodiment, the steering sensor system 4 comprises a sensor arrangement with which the torque and the angle of rotation of the steering wheel 2 or the steering shaft 3 can be detected. As described in the embodiments described above, the sensor arrangement may also be designed to detect only the torque or the angle of rotation.Such configurations are designed analogously to the sensor arrangements described below, except that they contain only one or more torque sensors (torque sensor ICs) or one or more angle sensors (angle sensor ICs). The following exemplary descriptions (and, moreover, the descriptions above) apply analogously with regard to the acquisition of the respective steering parameters and the associated data transmission.

[0042] The steering system 1 further includes a power steering module 5 for electric power steering, comprising, for example, a feedback actuator. The power steering module 5 can be used, for example, to generate forces or resistance at the steering wheel 2 to assist the driver during steering movements and / or to provide the driver with haptic feedback regarding road conditions, road surface irregularities, and / or vehicle dynamics. The power steering module 5 can contribute to improving vehicle and steering stability by responding to specific driving conditions and, for example, providing steering assistance or corrections.

[0043] The steering support module 5 forms a component of a control system for the steering system 1.

[0044] This steering support module 5 can be controlled by one or more electronic control units based on steering parameters, such as the rotation angle or torque of the steering wheel 2 or the steering shaft 3, to provide steering support or correction, thus enabling precise steering and haptic feedback adapted to the respective steering conditions despite electrically assisted steering.

[0045] The steering assistance module 5 can, for example, include an electric motor for steering assistance. In the illustrated embodiment, the steering shaft 3 is connected to a rack 7 via a gearbox 6, the rack 7 being designed to adjust the steering angle of the steered wheels 8 corresponding to the steering input. Other wheel steering actuator systems based on different mechanical transmission methods are also possible.

[0046] Fig. Figure 2 shows a first exemplary implementation of the steering sensor system 4 for a motor vehicle. The steering sensor system 4 comprises two subunits, the first being a torque sensor unit 9, abbreviated TSU (Torque Sensing Unit), and the second being an electronic control unit 10, abbreviated ECU (Electric Control Unit).

[0047] The TSU 9 comprises first and second torque sensor ICs 11 and 12, as well as first and second angle sensor ICs 13 and 14. The ECU 10 comprises a main control unit 15, or MCU (Main Controller Unit), and, with regard to the steering sensor system 1 as such - although in Fig. Figure 2 shows a low-dropout voltage regulator 16 (LDO) and a session border controller 17 (SBC), which are optionally available. The SBC 17 acts as a bridge element between different (on-board) networks of the vehicle, particularly the steering control system, and ensures safe and efficient communication. The LDO 16 is a linear voltage regulator typically used in electronic circuits to regulate an output voltage with minimal dropout voltage.

[0048] In terms of circuit technology, the design of the Fig. 2 The usual nomenclature is used, where: GND 1 is a first ground, GND 2 is a second ground, VDD 1 is a first supply voltage and VDD 2 is a second supply voltage, VDD_OUT is an output voltage of the SBC 17, VDD_LDO is a supply voltage of the SBC 17 for the LDO 16, GND is ground, VDD_MCU is a supply voltage of the SBC 17 for the MCU 15, V_IN is an input voltage of the LDO 16 and VOUT is an output voltage of the LDO 16. The corresponding connections 18 (pins) of the components (marked with solid square borders) are connected via lines 19 or conductor tracks 20 (marked by solid lines).

[0049] The first torque sensor IC 11 of the TSU 9 comprises two first torque sensor dies Trq1 and Trq2 for measuring the torque of the steering wheel 2 and the steering shaft 3, respectively, and for generating two torque measurements. The second torque sensor IC 12 of the TSU 9 comprises two second torque sensor dies Trq3 and Trq4, also for measuring the torque of the steering wheel 2 and the steering shaft 3, respectively, and for generating two further torque measurements.

[0050] The first rotation angle sensor IC 13 of the TSU 9 has a first rotation angle measurement channel ANG1 for measuring the rotation angle of the steering wheel 2 or the steering shaft 3 and for generating a rotation angle measurement value. The second rotation angle sensor IC 14 of the TSU 9 has a second rotation angle measurement channel ANG2, also for measuring the rotation angle of the steering wheel 2 or the steering shaft 3 and for generating another rotation angle measurement value.

[0051] Torque sensor ICs 11 and 12 are each configured as dual sensor ICs, meaning they each have two sensor dies for measuring torque. Angle sensor ICs 13 and 14, on the other hand, are each configured as single sensors or single-channel sensor ICs, meaning they each have only one measurement channel or sensor for the angle of rotation. With sensor ICs 11 to 14, redundant measurement of torque (4x) and angle of rotation (2x) is possible. In some configurations, the angle sensor ICs can also be configured as dual sensor ICs. Furthermore, sensors with more than two measurement channels are possible.

[0052] In operation to determine the torque and rotation angle of the steering wheel 2 or the steering shaft 3, the first torque sensor IC 11 determines two torque measurements via the two first torque sensor dies Trq1 and Trq2 and encodes these into a single first communication message K1. Similarly, the second torque sensor IC 12 determines two further torque measurements via the two second torque sensor dies Trq3 and Trq4 and encodes these into a single second communication message K2. Furthermore, the rotation angle sensor ICs 13 and 14 each determine a rotation angle measurement via the rotation angle measurement channels ANG1 and ANG2, with the third and fourth sensor ICs encoding the respective rotation angle measurement into a third and fourth communication message K3 and K4.

[0053] In the illustrated embodiment, the sensor ICs 11 to 14, the TSU 9, and the MCU 15 are configured for data transfer based on a (synchronous) SPC. Upon receiving a trigger or retrieval signal, which the MCU 15 sends to the respective sensor ICs 11 to 14 or the TCU 9, a transmission takes place (in Fig. 2 marked by arrows) of the respective communication message K1, K2, K3 or K4 from the sensor ICs 11 to 14 via MCU interfaces MCU / Interface to the MCU 15 by corresponding SPCs, which in Fig. The sensor ICs 11 to 14 are labeled SPC1 (Short PWM Code 1) to SPC4 (Short PWM Code 4). The SPCs received by MCU 9 after transmission are labeled SPC 1 / MCU to SPC 4 / MCU. After transmission, the MCU can decode the SPCs and further process the resulting torques and angles of rotation.

[0054] In the circuit shown, it is advantageous according to the invention that the two torque measured values ​​from the torque sensor dies Trq1 / Trq2 and Trq3 / Trq4 are each transmitted in a single communication message K1 or K2, respectively. According to the invention, this transmission can take place over only one physical data line, either individually or in its entirety. This reduces the implementation effort, for example, with regard to the number of signal lines and pins.

[0055] Due to the multiple sensor ICs 11 to 14 and only one MCU 15, the setup can be arranged according to Fig. 2 can be described as a single / semi-dual actuator system.

[0056] Fig. Figure 3 shows a second exemplary implementation of a steering sensor system for a motor vehicle, wherein in Fig. Three identical or functionally equivalent components and quantities are designated with the same reference symbols. The implementation according to Fig. 3 differs from the implementation according to Fig. 2 in that instead of one ECU 10 and one MCU 15, two ECUs 10A and 10B are provided, each with one MCU 15A and 15B.

[0057] The first MCU 15A is assigned the first torque sensor IC 11, the first angle sensor IC 13, and the second angle sensor IC 14. The second MCU 15B is assigned the second torque sensor IC 12.

[0058] Apart from the assignment of sensor ICs 11 to 14 to different MCUs, the function and acquisition of the steering parameters is analogous to the above. This means that the first torque sensor IC 11 determines the first and second torque measurements based on the first and second torque sensor dies Trq1 and Trq2. The first torque sensor IC 11 encodes these two torque measurements into a first communication message K1, which is transmitted to the first MCU 15A based on an SPC, here SPC1, using only one physical data line for the transmission of the first communication message K1, i.e., for the two torque measurements.

[0059] The same applies to the second torque sensor IC 12. Based on the third and fourth torque sensor dies Trq3 and Trq4, this IC determines the third and fourth torque measurements. The second torque sensor IC 12 encodes these two torque measurements into a second communication message K2, which is transmitted to the second MCU 15B based on an SPC, here SPC2. Only one physical data line is used for the transmission of the second communication message K2, i.e., for the two torque measurements.

[0060] The first rotary angle sensor IC 13 determines an initial rotary angle measurement value via the first rotary angle measurement channel ANG1. The first rotary angle sensor IC 13 encodes the rotary angle measurement value into a third communication message K3, which is transmitted to the first MCU 15A based on SPC, here SPC3, whereby only one physical data line is used for the transmission of the third communication message K3, i.e., for the first rotary angle measurement value.

[0061] Similarly, the second rotary angle sensor IC 14 determines a second rotary angle measurement value via the second rotary angle measurement channel ANG2. The second rotary angle sensor IC 14 encodes the rotary angle measurement value into a fourth communication message K4, which, based on SPC (here SPC4), is also transmitted to the first MCU 15A, whereby only one physical data line is used for the transmission of the fourth communication message K4, i.e., for the second rotary angle measurement value.

[0062] As I said, the function of the implementation is according to Fig. 3 for recording and transmitting the measured values ​​analogous to that of the Fig. 2. The implementations differ only in that... Fig. 3. Two separate ECUs with respective MCUs and different assignment of sensor ICs are present.

[0063] Fig. Figure 4 schematically illustrates a process flow for one embodiment of the invention, using the determination of torque as an example. The process flow comprises the following steps: - Acquisition (S1) of the torque by a first (11) of one or more sensor ICs (11, 12, 13, 14), which first sensor IC (11) comprises at least two first sensor dies (Trq1, Trq2), wherein the acquisition of the steering parameter comprises at least dual generation of measured values ​​for the steering parameter by the at least two first sensor dies (Trq1, Trq2) of the first sensor IC (11), - Encoding (S2) the measured values ​​by the first sensor IC (11) into a single first communication message (K1) and providing (S3) the first communication message (K1) by the first sensor IC (11) for data transfer to the control unit (15; 15A), and - Transmission (S4) of the first communication message (K1) encoding the measured values ​​to a first data communication interface (SPC1 / Interface) of the control unit from a second data communication interface of the first (11) of the one or more sensor ICs (11, 12, 13, 14) via a single first physical data line (19) which galvanically connects the first and second data communication interfaces for the purpose of data transfer.

[0064] The method can also be applied to the other sensor ICs 12, 13, 14, particularly if they implement dual acquisition of the respective steering parameter. As described above, the respective data lines can at least partially coincide, and / or, for example, data communication interfaces can also coincide when data lines coincide. Regarding the implementation, reference is made to the explanations above, which apply analogously. In particular, the communication messages can be, according to the different implementations as described in the exemplary embodiments, Fig. 2 and Fig. 3 will be transferred.

[0065] The above explanations show that the embodiments according to the invention solve the underlying problem. Apart from the variants described in connection with the exemplary embodiments shown in the figures, further variants described in the embodiments of the invention are conceivable within the scope of the invention, which can be implemented accordingly and combined with one another in any combination. Reference sign 1 Steering system 2 Steering wheel 3 Steering shaft 4 Steering sensor system 5 Steering Assistance Module 6 gearboxes 7 Rack 8 steered wheel 9 Torque and Angle Sensor Unit (TSU) 10, 10A, 10B electronic control unit (ECU) 11 first torque sensor IC 12 second torque sensor IC 13 first rotary angle sensor IC 14 second rotation angle sensor IC 15, 15A, 15B Main Control Unit (MCU) 16 Low-Dropout Voltage Regulators (LDO) 17 Session Border Controller (SBC) 18 connections 19 lines 20 conductor tracks Trq1, Trq1 first and second torque sensor-The Trq3, Trq4 third and fourth torque sensor-The ANG1, ANG2 first and second rotation angle measuring channel GND, GND1, GND2 Ground VDD supply voltage VDD_OUT output voltage VDD_IN Input voltage SPC1..SPC4 Short PWM Code VDD_LDO LDO power supply VDD_MCU Power supply MCU SPC1..4 / Interface SPC Interfaces SPC1..4 / MCU SPC to MCU (after transmission) K1..K4 communication messages 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] EP 2 983 962 B1

[0005]

Claims

[1] Steering sensor system (4) for an electrically assisted steering system (1) in a motor vehicle, in particular for a steer-by-wire steering system in a motor vehicle, comprising: - one or more control units (15; 15A, 15B), and - one or more sensor ICs (11, 12; 13, 14), wherein - one (15, 15A) of the one or more control units (15, 15A, 15B) has a first data communication interface (SPC1 / Interface) and one (11) of the one or more sensor ICs (11, 12, 13, 14) has a second data communication interface, - the first and second data communication interfaces are galvanically connected to each other via a first physical data line (19), - the first sensor IC (11) is configured to detect a steering parameter of a steering wheel of the steering system, wherein the steering parameter includes a torque or a rotation angle of the steering wheel (2); characterized by , that - the first sensor IC (11) includes at least two first sensor dies (Trq1, Trq2) for at least dual generation of measured values ​​for the steering parameter, - the first sensor IC (11) is configured to encode at least dual first measured values ​​for the steering parameter generated by the first sensor dies (Trq1, Trq2) in a single first communication message (K1), and - the first sensor IC (11) and the control unit (15; 15A, 15B) are set up for data transfer of the single first communication message (K1) via a single first physical data line (19). [2] Steering sensor system (4) according to claim 1, wherein a second (12) of the one or more sensor ICs (11, 12, 13, 14) is configured to also detect the steering parameter, in particular a torque, detected by the first sensor IC (11), and the second sensor IC (12) comprises at least two second sensor dies (Trq3, Trq4) for at least dual generation of measured values ​​for the steering parameter, wherein the second sensor IC (12) is configured to encode at least dual second measured values ​​for the steering parameter generated by the second sensor dies (Trq3, Trq4) of the second sensor IC (12) in a single second communication message (K2), and wherein - the second sensor IC (12) and the control unit (15) are set up for data transfer of the single second communication message (K2) between the second sensor IC (12) and the control unit (15) via a single second physical data line (19) between a further second data communication interface of the second sensor IC (12) and a further first data communication interface (SPC2 / Interface) of the control unit (15), or - the steering sensor system (4) comprises two control units (15A, 15B) and the two sensor ICs (11, 12) and the two control units (15A, 15B) are set up for data transfer of the first and second communication messages (K1, K2) between the two sensor ICs (11, 12) and the two control units (15A, 15B) via a single second physical data line (19). [3] Steering sensor system (4) according to claim 1 or 2, comprising only a control unit (15) wherein the first sensor IC (11), and preferably a second sensor IC (12), is configured to detect the torque as a steering parameter, and wherein two further sensor ICs (13, 14) are configured to detect the rotation angle as a steering parameter and to generate an additional communication message (K3; K4) encoding the rotation angle for data transfer via a respective additional physical data line (19) to the control unit (15). [4] Steering sensor system (4) according to claim 1 or 2, comprising two control units (15A, 15B) wherein the first sensor IC (11), and preferably a second sensor IC (12), is configured to detect the torque as a steering parameter, and wherein two further sensor ICs (13, 14) are provided which are configured to detect the rotation angle as a steering parameter and to generate an additional communication message (K3; K4) encoding the rotation angle for data transfer via a respective additional physical data line (19) to one (15A) of the two control units (15A, 15B). [5] Steering sensor system (4) according to one of claims 1 to 4, wherein the data transfer is based on one of the following digital data communication protocols: PWM, SENT, SPC, SPI. [6] Steering sensor system (4) according to any one of claims 1 to 5, wherein the one or more control units (15; 15A, 15B) each form a main control unit which, in particular, each form part of a superior electronic control unit (10; 10A, 10B). [7] Steering system (1) for a motor vehicle, designed as an electronically assisted steering system (1), in particular as a steer-by-wire steering system, comprising a steering wheel (2) connected to a steering shaft (3) and a steering sensor system (4) according to any one of claims 1 to 6, wherein the one or more sensor ICs (11, 12, 13, 14) are coupled directly or indirectly to the steering wheel (2) or the steering shaft (3) for the purpose of detecting the torque and / or the angle of rotation as steering parameters. [8] Method for detecting a steering parameter of a steering wheel (2) or a steering shaft (3) of a steering system (1) designed according to claim 7, wherein the steering parameter comprises a torque or an angle of rotation, the method comprising the following steps: - Acquisition (S1) of the steering parameter by a first (11) of one or more sensor ICs (11, 12, 13, 14), which first sensor IC (11) comprises at least two first sensor dies (Trq1, Trq2), wherein the acquisition of the steering parameter comprises at least dual generation of measured values ​​for the steering parameter by the at least two first sensor dies (Trq1, Trq2) of the first sensor IC 11), - Encoding (S2) the measured values ​​by the first sensor IC (11) into a single first communication message (K1) and providing (S3) the first communication message (K1) by the first sensor IC (11) for data transfer to the control unit (15; 15A), and - Transmission (S4) of the first communication message (K1) encoding the measured values ​​to a first data communication interface (SPC1 / Interface) of the control unit from a second data communication interface of the first sensor ICs (11, 12, 13, 14) via a single first physical data line (19) which galvanically connects the first and second data communication interfaces for the purpose of data transfer. [9] The method of claim 8, further comprising: - Acquisition of the steering parameter acquired by the first sensor IC (11) further by a second (12) of the one or more sensor ICs (11, 12, 13, 14), which comprises at least two second sensor dies (Trq3, Trq4) for the at least dual generation of measured values ​​for the steering parameter, wherein the acquisition by the second sensor IC (12) comprises at least dual generation of second measured values ​​for the steering parameter by the at least two second sensor dies (Trq3, Trq4), - Encoding the measured values ​​by the second sensor IC (12) into a single second communication message (K2) and providing the second communication message (K2) by the second sensor IC (12) for data transfer, the method further comprising: - Transmission of the second communication message (K2) encoding the measured values ​​to a further second data communication interface (SPC2 / Interface) of the control unit from a further first data communication interface of the second sensor IC (12) via a single second physical data line (19) which galvanically connects the first and second data communication interfaces for the purpose of data transfer, or - Transmission of the second communication message (K2) encoding the measured values ​​to a further second data communication interface (SPC2 / Interface) of a further second control unit from a further first data communication interface of the second sensor IC (12) via a single second physical data line, which galvanically connects the first and second data communication interfaces to each other for the purpose of data transfer. [10] Method according to claim 8 or 9, further comprising at least one of the following features: - Detection of the torque by the first sensor IC (11), preferably also by the second sensor IC; detection of the rotation angle as a steering parameter by a third sensor IC (13, 14), preferably by two third sensor ICs (13, 14), of the one or more sensor ICs (11, 12, 13, 14), generation and provision of at least one additional communication message (K3; K4) encoding the rotation angle for a data transfer, and transmission of the at least one additional communication message (K3; K4) via a respective additional physical data line to one (15, 15A,) of the one or more control units; - Transmission of the communication message(s) (K1, K2, K3, K4) based on one of the following data communication protocols: PWM, SENT, SPC, SPI.

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