EP3583333A1

EP3583333A1 - Method for controlling an actuator for a vehicle, control appliance and parking lock device for a vehicle

Info

Publication number: EP3583333A1
Application number: EP18702114.2A
Authority: EP
Inventors: Sascha TRÄNKNER
Original assignee: ZF Friedrichshafen AG
Current assignee: ZF Friedrichshafen AG
Priority date: 2017-02-20
Filing date: 2018-01-15
Publication date: 2019-12-25
Also published as: WO2018149573A1; DE102017202647A1; US20200003304A1; CN110291312A

Abstract

The invention relates to a method for controlling an actuator (104) for a vehicle (100), the actuator (104) being coupled or couplable to a drive unit (106) for driving the actuator (104) and to a sensor (110), by means of a sensor transmission (108), for detecting a position and/or a change in position of the sensor transmission (108). According to said method, a sensor signal (114) is first read, which represents a position detected by the sensor (110) and/or a change in position of the sensor transmission (108). The sensor signal (114) is used in another step, together with a transmission ratio of the sensor transmission (108), to determine actuator information representing a position and/or change in position of the actuator (104). A suitable control signal (116) for controlling the actuator (104) is produced using the actuator information.

Description

A method for driving an actuator for a vehicle, control unit and

Parking lock device for a vehicle

The present invention relates to a method for driving an actuator for a vehicle, to a corresponding control device, to a corresponding computer program and to a parking brake device for a vehicle.

DE 600 06 666 T2 describes a position controller for a motor which performs position control based on a load position signal from a position sensor mounted on a load driven by the motor.

Against this background, the present invention provides an improved method for driving an actuator for a vehicle, an improved control device, and an improved parking brake device for a vehicle according to the main claims. Advantageous embodiments will become apparent from the dependent claims and the description below.

The invention relates to a method for driving an actuator for a vehicle, wherein the actuator is coupled or coupleable to a drive unit for driving the actuator and via a sensor gear to a sensor for detecting a position and / or position change of the sensor gear, the method comprising the following steps having:

Reading in a sensor signal representing a position and / or position change of the sensor operation detected by the sensor;

Determining an actuator information representing a position and / or position change of the actuator using the sensor signal and a gear ratio of the sensor gear; and

Generating a drive signal for driving the actuator using the actuator information. An actuator can be understood, for example, as a cable pull or another component for mechanical actuation. In particular, the actuator component of a gearbox, for example, an automatic transmission, be. The actuator may be designed, for example, to activate a parking lock of the vehicle, for example by engaging a specific gear stage of the gearbox or by detecting a brake of the vehicle. By a drive unit, for example, an electric motor can be understood. A sensor gear may be understood to mean a gear which converts a movement of the actuator into a movement of a pulse generator detectable by the sensor in accordance with a predetermined gear ratio.

The approach described here is based on the recognition that a sensor gear can be used for simple and unambiguous detection of a position or position change of an actuator in a vehicle, for example a parking lock actuator in the form of a cable pull. In particular, such a detection offers the advantage that the position or position change of the actuator can be calculated directly from a position or position change of the sensor operation. Thus, for example, an additional evaluation of a sensor signal waveform for position determination can be dispensed with.

According to one embodiment, in the step of determining, the sensor signal may be converted directly to the position of the actuator using the gear ratio of the sensor operation to obtain the actuator information. This makes it possible to determine the position of the actuator particularly quickly and efficiently.

According to another embodiment, in a step of determining, a rotational speed of the drive unit may be determined using the actuator information. Accordingly, in the step of generating, the driving signal can be generated by using the rotational speed. As a result, a reliable determination of the rotational speed of the drive unit is made possible. The actuator can be coupled via a drive gear with the drive unit or coupled. In the step of generating, the drive signal may accordingly be generated using a gear ratio of the drive gear. This allows precise control of the actuator when using a drive gear.

It is also advantageous if in the step of generating the drive signal is generated to set a desired speed for moving the actuator into a desired position. This allows the actuator to be moved at different speeds.

According to a further embodiment, in the step of reading an analog signal can be read as the sensor signal. This allows easy processing of the sensor signal.

The approach presented here also creates a control unit which is designed to execute, to control or to implement the steps of a variant of a method presented here in corresponding devices. Also by this embodiment of the invention in the form of a control device, the object underlying the invention can be achieved quickly and efficiently.

For this purpose, the control unit can have at least one arithmetic unit for processing signals or data, at least one memory unit for storing signals or data, at least one interface to a sensor or an actuator for reading sensor signals from the sensor or for outputting control signals to the actuator and / or or at least a communication interface for reading or outputting data embedded in a communication protocol. The arithmetic unit may be, for example, a signal processor, a microcontroller or the like, wherein the memory unit may be a flash memory, an EPROM or a magnetic memory unit. The communication interface can be designed to read in or output data wirelessly and / or by line, wherein a communication interface, the line-bound Read in or output data, this data, for example, electrically or optically read from a corresponding data transmission line or can output to a corresponding data transmission line.

In the present case, a control device can be understood as meaning an electrical device which processes sensor signals and outputs control and / or data signals in dependence thereon. The control unit may have an interface, which may be formed in hardware and / or software. In the case of a hardware-based design, the interfaces can be part of a so-called system ASIC, for example, which contains various functions of the control unit. However, it is also possible that the interfaces are their own integrated circuits or at least partially consist of discrete components. In a software training, the interfaces may be software modules that are present, for example, on a microcontroller in addition to other software modules.

In an advantageous embodiment, the control unit is used to control the vehicle. For this purpose, the control unit can access, for example, sensor signals such as acceleration, pressure, steering angle or environmental sensor signals. The control is effected via actuators such as brake or steering actuators or an engine control unit of the vehicle.

The approach presented here also creates a parking brake device for a vehicle, wherein the parking brake device has the following features: an actuator for activating the parking brake; a drive unit for driving the actuator; a sensor gear; a sensor for detecting a position and / or position change of the sensor operation, wherein the actuator is coupled via the sensor gear with the sensor; and a control device according to a preceding embodiment.

The parking lock device may be formed as part of an automated shift operation, wherein the automated shift operation is configured to perform a plurality of functions, such as the engagement of a reverse, forward and / or neutral gear.

According to one embodiment, the actuator may be realized as a cable pull. As a result, a high load capacity of the actuator can be ensured with low weight and small footprint.

Also of advantage is a computer program product or computer program with program code which can be stored on a machine-readable carrier or storage medium such as a semiconductor memory, a hard disk memory or an optical memory and for carrying out, implementing and / or controlling the steps of the method according to one of the embodiments described above is used, especially when the program product or program is executed on a computer or a device.

The invention will be described by way of example with reference to the accompanying drawings. Show it:

Figure 1 is a schematic representation of a vehicle with a parking brake device according to an embodiment;

Figure 2 is a schematic representation of a parking brake device according to an embodiment;

Figure 3 is a schematic representation of a control device according to an embodiment; and

FIG. 4 shows a flow chart of a method according to an exemplary embodiment. In the following description of preferred embodiments of the present invention, the same or similar reference numerals are used for the elements shown in the various figures and similarly acting, wherein a repeated description of these elements is omitted.

FIG. 1 shows a schematic representation of a vehicle 100 with a parking brake device 102 according to an exemplary embodiment. The parking brake device 102 includes an actuator 104 for activating a parking lock of the vehicle 100, by which it can be prevented that the vehicle 100 rolled away in the parked state, as indicated in Figure 1 by way of example. According to the embodiment shown in Figure 1, the actuator 104 is designed as a cable, such as the mechanical actuation of a gearbox, in particular an automatic transmission, or a brake system of the vehicle 100. Alternatively, the actuator 104 may be formed as any other mechanical actuator, such as in Shape of a lever or a rack. The actuator 104 is coupled to a suitable drive unit 106, for example in the form of a servomotor, for adjusting the actuator 104. In addition, the actuator 104 is coupled to a sensor gear 108, wherein the sensor gear 108 has a sensor 1 10 for detecting a position or position change of the sensor gear 108. Both the sensor 1 10 and the drive unit 106 are connected to a control unit 1 12 for controlling the drive unit 106.

The control unit 12 is designed to read from the sensor 1 10 a sensor signal 1 14 representing the position or position change of the sensor gear 108 and to evaluate this taking into account a predetermined gear ratio of the sensor gear 108 to determine a position or position change of the actuator 104. Depending on the result of this evaluation, the control unit 1 12 generates a suitable drive signal 1 16 for driving the drive unit 106 as a function of the position or position change of the actuator 104 ascertained with the aid of the sensor operation. Advantageously, the position or position change of the actuator 104 can be due to the known transmission ratio of the actuator Sensor gear 108 here directly from the position or position change of the sensor operation 108, as detected by the sensor 1 10, are determined by the control unit 1 12.

By detecting the actuator position and the regulation of the actuator drive via the sensor gear 108, a basic function by which the actuator 104 is positioned and moved can be implemented with relatively little technical effort. In particular, the use of the sensor gear 108 allows the simple implementation of a method for one-sided positioning of a cable in the vehicle 100 and for speed control of the change in position of the cable by means of the sensor 1 10th

Figure 2 shows a schematic representation of a parking brake device 102 according to an embodiment. The parking brake device 102 essentially corresponds to the parking brake device described above with reference to FIG. 1, with the difference that the drive unit 106 according to this exemplary embodiment is mechanically coupled to the actuator 104 via an optional drive gear 200. Accordingly, the drive of the drive unit 106 is additionally taking into account a predetermined transmission ratio of the drive gear 200, as described in more detail below.

For example, an entire working range of the actuator 104 in the measuring range of the sensor 110 is represented by the sensor gear 108. Thereby, the unique position of the actuator 104 can be calculated. By the sensor waveform over time, for example, the rotational speed of the drive unit 106 due to the known gear ratio of the sensor gear 108 and the drive gear 200 can be controlled. Thus, using the sensor 1 10 two functions can be realized.

The sensor gear 108 is designed, for example, so that the measurement accuracy is increased. As a result, the unique assignment is lost and reference points are required, for example if the working range of the actuator 104 corresponds to more than one sensor rotation. The approach presented here now allows the one-to-one positioning of the actuator 100 in the vehicle, in particular a cable, and a speed control of the position change with the aid of the sensor 110. According to one exemplary embodiment, an actual position x of the actuator 104 and a speed dx / dt of the actuator 104 determined. In this case, the sensor 110 is moved via the sensor gear 108 in such a way that an unambiguous position determination of the actuator 104 on the basis of a measurement signal y, also called sensor signal, is possible at any time. A measuring range Y of the sensor 110 includes an entire position range X of the actuator 104. For the determination of the actual position x of the actuator 104, therefore, no evaluation of a sensor signal course of the sensor 110 is required. Instead, the measurement signal y is converted directly to the actual position x based on the transmission ratio of the sensor operation. Due to the change in position of the sensor 110 over time (dy / dt), a rotational speed of the drive unit 106 is determined directly. On the basis of the transmission ratio of the drive gear 200 thus the speed dx dt of the actuator 104 is controlled. The measurement signal y is, for example, an analog signal.

For example, the control of a cable comprises the following steps.

In a first step, the cable pull position, previously also called the actual position x, is determined on the basis of the measurement signal y, d. H. based on an actual position of the sensor, and the sensor gear ratio detected.

In a second step, the control of a desired speed dx dt of the cable is based on the sensor signal change dy / dt and the sensor and drive gear ratio.

In a third step, the positioning of the cable in the position range X and a permanent position monitoring or correction on the basis of the measurement signal y. FIG. 3 shows a schematic representation of a control device 1 12 according to an exemplary embodiment, for example a control device described above with reference to FIG. The control unit 1 12 comprises a read-in unit 310 for reading in the sensor signal 1 14, wherein the read-in unit 310 is connected to a determination unit 320 for determining an actuator information 322 representing the position or position change of the actuator using the sensor signal 1 14 and the transmission ratio of the sensor operation. The determination unit 320 transfers the actuator information 322 to a generation unit 330, which is designed to generate the drive signal 16 for driving the drive unit using the actuator information 322.

FIG. 4 shows a flow diagram of a method 400 according to one exemplary embodiment. The method 400 for driving an actuator for a vehicle may, for example, be carried out using a control device as described above with reference to FIGS. 1 to 3. In this case, in a step 410, the sensor signal provided by the sensor of the sensor operation is read in and used in a step 420 in combination with the known transmission ratio of the sensor operation in order to determine the actuator information. In a step 430, the drive signal for driving the drive unit is generated using the actuator information.

If an exemplary embodiment comprises a "and / or" link between a first feature and a second feature, this can be read so that the embodiment according to one embodiment, both the first feature and the second feature and according to another embodiment, either only the first Feature or only the second feature. REFERENCE CHARACTERS

100 vehicle

102 parking lock device

04 actuator

106 drive unit

108 sensor gear

1 10 sensor

1 12 control unit

1 14 sensor signal

1 16 drive signal

200 drive gear

310 reading unit

320 Investigation unit

322 actuator information

330 generating unit

400 A method for driving an actuator for a vehicle

410 step of reading

420 step of the determination

430 step of creating

Claims

claims

1 . Method (400) for driving an actuator (104) for a vehicle (100), wherein the actuator (104) is provided with a drive unit (106) for driving the actuator (104) and a sensor drive (108) with a sensor (10 ) for detecting a position and / or position change of the sensor operation (108) is coupled or coupled, wherein the method (400) comprises the following steps:

Reading (410) a sensor signal (1 14) representing a position and / or position change of the sensor operation (108) detected by the sensor (110);

Determining (420) an actuator information (322) representing a position and / or position change of the actuator (104) using the sensor signal (1 14) and a gear ratio of the sensor gear (108); and

Generating (430) a drive signal (1 16) to drive the actuator (104) using the actuator information (322).

2. Method (400) according to claim 1, wherein in the step of determining (420) the sensor signal (1 14) is converted directly to the position of the actuator (104) using the transmission ratio of the sensor drive (108) to obtain the actuator information (400). 322).

3. The method (400) according to claim 1, further comprising a step of determining a rotational speed of the drive unit using the actuator information, wherein in the step of generating the drive, the drive signal is used the speed is generated.

4. Method (400) according to one of the preceding claims, in which the actuator (104) is coupled or coupleable to the drive unit (106) via a drive gear (200), wherein in the step of generating (430) the drive signal (1 16) is generated using a gear ratio of the drive gear (200).

5. The method (400) according to one of the preceding claims, wherein in the step of generating (430) the drive signal (116) is generated to set a target speed for the method (400) of the actuator (104) in a desired position.

6. Method (400) according to one of the preceding claims, wherein in the step of reading (410) an analog signal is read in as the sensor signal (114).

A controller (112) having units (310, 320, 330) configured to perform and / or drive the method (400) of any one of claims 1 to 6.

8. A parking brake device (102) for a vehicle (100), the parking brake device (102) comprising: an actuator (104) for activating the parking brake; a drive unit (106) for driving the actuator (104); a sensor gear (108); a sensor (110) for detecting a position and / or position change of the sensor gear (108), wherein the actuator (104) is coupled to the sensor (110) via the sensor gear (108); and a controller (112) according to claim 7.

9. parking brake device (102) according to claim 8, wherein the actuator (104) is realized as a cable.

A computer program configured to execute and / or drive the method (400) according to any one of claims 1 to 6.

11. A machine-readable storage medium on which the computer program according to claim 10 is stored.