Method for activating a start-up function, and control device

Abstract

The technology disclosed by the invention relates to a method for activating a start-up function of at least one sensor (31, 32) of a motor vehicle (10). According to said method it is determined that a start-up of the motor vehicle (10) is imminent and the start-up is activated in response thereto. The technology disclosed here also relates, according to the invention, to an associated control device (40).

Description

[0001] Method for activating a start-up function and control device

[0002] The technology disclosed here relates to a method for activating a start-up function and an associated control device.

[0003] Start-up functions are typically performed on sensors in motor vehicles to ensure their operational readiness. For example, sensors such as a temperature sensor or a pressure sensor may need to be preheated or otherwise conditioned so that they can perform their required task as best as possible. When a vehicle is started, for example by a driver getting in and pressing a start button, such a start-up function is typically initially activated before the sensor's full performance is available after the start-up function has ended. This can result in a period of time during which the sensor's full performance is not yet available, even though this would actually be desirable for the operation of the vehicle.

[0004] It is a preferred object of the technology disclosed here to reduce or eliminate at least one disadvantage of a previously known solution or to propose an alternative solution. In particular, it is a preferred object of the technology disclosed here to provide a method for activating a start-up function that enables a sensor to be ready for operation earlier. Further preferred objects can arise from the advantageous effects of the technology disclosed here. The objects are achieved by the subject matter of the independent patent claims. The dependent claims represent preferred embodiments.

[0005] The technology disclosed here relates to a method for activating a start-up function of at least one sensor of a motor vehicle. The method comprises the following steps:

[0006] Determining that a start of the motor vehicle is imminent, and in response to determining that a start of the motor vehicle is imminent, activating the start-up function.

[0007] Using such a method, the start-up function can be preceded by the vehicle's start-up. This ensures that the full functionality of a sensor is available earlier, ideally as soon as the vehicle is started. The start-up function can begin as soon as the vehicle is about to start, rather than only when the vehicle has actually been started. The start-up function can thus be postponed to a time when the sensor's functionality is not yet required.

[0008] A start-up function is understood in particular to be a function which serves to make a sensor ready for operation. In particular, this can involve, for example, heating up or activating a voltage supply to the sensor. Such a start-up function typically requires a certain amount of time, during which time the sensor may in principle be functional, but will not achieve the reliability it has after the start-up function has been completed. Determining that a start-up of the motor vehicle is imminent can be done in different ways. In particular, determining that a start-up of the motor vehicle is imminent means evaluating indicators which indicate an imminent start of the motor vehicle. Typical embodiments are described further below.In principle, different implementations are possible, which can also be combined with one another. Typically, one implementation involves evaluating information to predict a motor vehicle start. Determining that a motor vehicle start is imminent is typically achieved by setting a flag or variable, or, for example, by calling a specific procedure in a controller. In response, the start-up function is then activated, allowing the sensor to be preconditioned in a timely manner.

[0009] Typically, sensors for which a start-up function is activated are not yet designed to perform any measuring tasks while the start-up function is being executed. This can prevent unreliable measured values ​​from being obtained. It can also prevent any measuring task of the sensor from interfering with the start-up function. Typically, the sensor's measuring task is activated immediately after the start-up function has been completed. Measuring tasks can be deactivated, for example, by not reading out data, by not yet supplying power to components required to perform a measurement, or by moving the sensor into a configuration in which it is not performing a measuring task through mechanical movement or by actuating external elements such as valves.It is possible, for example, to separate the sensor from a medium to be measured in order to prevent a measurement task from being carried out.

[0010] For example, determining that a start of the motor vehicle is imminent can be carried out in response to detecting a user approaching the motor vehicle. This typically indicates an imminent start, as the user approaches the motor vehicle and, in most cases, then also intends to use it. Such an approach can be detected, for example, by means of a transmitter that the user carries with them. This can be, for example, a typical electronic key for remotely operating a central locking system. It can also be a signature card or a similar device. Alternatively or additionally, a camera or other environment detection system can be used, for example, to detect a user approaching the motor vehicle.

[0011] In particular, the approach of a user to the motor vehicle can be detected by means of a transmitter worn by the user. This transmitter can be integrated, for example, into a vehicle key, a cell phone, a key card, or another object. This allows for simple and reliable detection of a user's approach. For example, the transmitter can have a unique identification, allowing the motor vehicle to clearly identify that a transmitter assigned to it is approaching. False activations can be advantageously prevented in this way.

[0012] According to one embodiment, the determination that a start of the motor vehicle is imminent occurs in response to a user activating a function of the motor vehicle. This typically involves a manual activation, which the user performs, for example, via a control display or a remote control or another portable device such as a mobile phone. In particular, it can involve activating a function such as an auxiliary heater, auxiliary air conditioning, or lighting. This also typically indicates that the user intends to use the motor vehicle shortly.

[0013] According to one embodiment, the determination that a start of the motor vehicle is imminent occurs in response to the motor vehicle independently activating a function. Such functions can typically be activated by the motor vehicle itself, without requiring manual input from a user or any interaction with the user. In particular, these can be specifically predetermined functions. For example, these can be functionalities for preserving the service life of a fuel cell or another component. For example, they can be post-drying, frost preparation, high-voltage battery charging, or another functionality that the motor vehicle can perform without interaction with the user. Such functionalities are typically performed when stationary.They are intended in particular to extend the service life of components and / or the operational readiness of the motor vehicle.

[0014] In particular, it can be provided that at least one group of equivalent sensors is present. Equivalent sensors are understood to be those that perform an identical or at least very similar measurement task and / or that can at least partially substitute for one another. The sensors can also be said to be redundant to one another. This can achieve redundancy, which increases safety. In particular, several such groups of equivalent sensors can be present. However, only one such group can also be present.

[0015] In particular, it can be provided that, when the start-up function is activated in at least one group, this is only activated for some of the equivalent sensors in a group. This makes it possible to ensure that only one sensor, or at least only some of the sensors in a group, are subjected to a start-up function, with the other sensors typically not receiving a start-up function and typically not being activated during subsequent operation of the motor vehicle, or at least only being activated later. A start-up function for the other sensors can, for example, only begin when the motor vehicle is started; alternatively, the other sensors can remain inactive and not be used until the next activation. This enables targeted control of the usage situation and thus also of the aging of the sensors.

[0016] In particular, several groups of equivalent sensors can be present. These can, for example, perform specific measurement tasks, with the sensors in a group typically being able to fully or at least partially substitute for one another.

[0017] In particular, it can be provided that the startup function is activated for different sensors in a group upon consecutive activations. For example, in a group consisting of three sensors, the first sensor can be used upon activation, the second sensor upon a subsequent activation, and the third sensor upon a subsequent activation. Then, the process can begin again from the beginning, i.e., with the first sensor. This enables load control, which ensures even utilization of the sensors and leads to even aging.

[0018] In particular, it can be provided that, in the case of multiple consecutive activations, the start-up function is activated according to a predefined pattern among the sensors in a group. The pattern can, in particular, specify which sensor(s) are used during an activation and, accordingly, a start-up function is executed for them. The pattern can be the same for all activations or differ from activation to activation. This allows for targeted load control of the sensors.

[0019] According to one embodiment, the same sensor(s) in a group are always activated during all activations, but not all sensors in that group. This allows some sensors in that group to be specifically aged compared to the others in that group. This can, for example, result in these sensors being replaced sooner, while the other, generally non-activated sensors have a longer service life and are replaced later. The term "all activations" refers in particular to a longer period of time, for example during the service life of a vehicle or between maintenance intervals. It can in particular refer to a period of at least one month, at least six months, or at least one year.

[0020] According to one embodiment, the start-up function is activated for only some of the sensors of a motor vehicle in response to the determination that a start of the motor vehicle is imminent. In particular, these can be safety-critical sensors. Other sensors, which are not safety-critical, are then typically only activated later, or their start-up function is activated. This can, for example, ensure that the safety-critical sensors are available as early as possible, whereas the start-up function for other sensors is only activated when a better power supply is available in the vehicle. Sensors that do not require a start-up function at all are typically left out of this consideration.

[0021] In particular, after the start-up function has ended, the sensor(s) can transition to a measuring function. The sensor is then typically conditioned by the start-up function and can perform its measuring functionality appropriately. The start-up function is then deactivated.

[0022] In particular, the start-up function can be or include warming up the sensor(s). For this purpose, a heating element can be activated, for example. This allows the sensor to reach its operating temperature, at which it can ideally perform its measurement task and / or at which it is calibrated. Heating can also be achieved by applying a conventional current to the sensor.

[0023] In particular, one or more sensors can be designed as a hydrogen sensor. The procedure described herein has proven particularly useful in this case. Hydrogen sensors can, in particular, detect the presence of hydrogen. They typically serve a safety purpose, as they can report a possible leak. In principle, however, the procedure described herein is also possible with other sensors. The technology disclosed here further relates to a control device for one or more sensors, wherein the control device is configured to carry out a method as described herein. The technology disclosed here also relates to a non-volatile computer-readable storage medium containing program code, upon execution of which a processor carries out a method described herein. With regard to the method, all embodiments and variants described herein can be used.

[0024] In other words, it is typically preferable to have safety-relevant sensors initially active and ready to measure when the vehicle is started. However, certain sensors typically have startup times that can lead to noticeable waiting times for the customer after the vehicle has started. Furthermore, for certain safety functions, decomposition into several redundant sensors may be necessary or desirable. In particular, this can eliminate common causes of failure. For example, aging over operating time can be a possible cause of a failure.

[0025] For example, when a vehicle key, a cell phone or a key card approaches, a relevant sensor can already be started up. This means it is already available when the customer is in the vehicle and wants to start the motor vehicle. Further waiting time is avoided or at least reduced. With redundant sensors, certain designs can provide for only one of, for example, two sensors to be activated. A distinction must be made between two cases here: a) always the same: prevention of common cause due to sensor aging, as one of the sensors is started more frequently (e.g. when approaching without the vehicle being in motion) and is in operation for longer, b) alternating activation: distribution of operation between both, optimisation of the service life of the sensors.

[0026] If the second sensor is activated at a later time than the first sensor, or, for example, at vehicle start-up, it is possible to use only one of the two redundant sensors. This is particularly possible if relevant functional safety requirements are still met.

[0027] A sensor, in particular a hydrogen sensor, can be designed, for example, as a fuel sensor. This can, in particular, be fluidly connected to a gas outlet, for example, of a fuel cell. For example, the fuel sensor can be arranged in the exhaust system of the fuel cell system, for example, in or downstream of a mixing area in which anode gas is mixed with cathode gas. Likewise, the fuel sensor can also be arranged in a vent line. Fuel sensors, such as hydrogen sensors, are known per se.

[0028] The technology disclosed here will now be explained in more detail using the drawing. It shows:

[0029] Fig. 1 : a motor vehicle for carrying out the method according to a first embodiment, and

[0030] Fig. 2: A motor vehicle for implementing the method according to a second embodiment. Fig. 1 shows a purely schematic illustration of a motor vehicle 10 suitable for implementing a method described herein. Only those components relevant to implementing the method are discussed.

[0031] The motor vehicle 10 has a fuel cell 20. The fuel cell 20 serves to supply the motor vehicle 10 with electrical energy, for example, to drive a traction drive machine. The motor vehicle 10 has an exhaust path 25, by means of which the fuel cell 20 can discharge anode exhaust gas and cathode exhaust gas to the environment. This typically contains small amounts of hydrogen, and such a hydrogen content is monitored. A first sensor 31 and a second sensor 32 serve this purpose. The sensors 31, 32 in the present case are hydrogen sensors which measure the hydrogen content in the exhaust path 25. The two sensors 31, 32 can be understood as a group. They are redundant and equivalent to one another. This can mean, in particular, that if one of the two sensors 31, 32 is not functioning, the other can take over its function.

[0032] The motor vehicle 10 further comprises a control device 40. The control device 40 is designed to read the two sensors 31, 32 so that a hydrogen content in the exhaust gas path 25 can be determined. In the embodiment implemented here, the control device 40 is further configured to detect whether a transmitter 50 is nearby. The transmitter 50 can, in particular, be a portable transmitter worn by a user of the motor vehicle 10 and continuously transmitting a radio signal. If the user approaches with the transmitter 50, this is detected by the control device 40. In this case, a start-up function is activated for one of the two sensors 31, 32. In the present case, this means that the respective sensor 31, 32 is heated up to reach an operating temperature. This occurs before a user starts the motor vehicle 10.When the user starts the motor vehicle 10, one of the two sensors 31, 32 is already fully operational and no waiting time is required to start driving the motor vehicle 10.

[0033] During consecutive activations, the control device 40 in the present configuration always activates the two sensors 31, 32 alternately. This leads to a uniform aging of the sensors 31, 32. In another implementation, it would also be possible, for example, to always subject only the first sensor 31 or the second sensor 32 to the start-up function, so that this sensor ages earlier. The other sensor 31, 32 is then typically only subjected to a start-up function when the motor vehicle is started, or alternatively, it remains deactivated.

[0034] Fig. 2 shows a motor vehicle 10 according to a second exemplary embodiment. This is largely identical to the first exemplary embodiment, however, the activation of the start-up function is not coupled to the approach of a sensor 50, but rather to the activation of an auxiliary heater (not shown) by means of a wireless operating device 60. The wireless operating device 60 is not designed in such a way as the transmitter 50 that it continuously emits a radio signal; rather, the wireless operating device 60 only emits a radio signal when a button 62 of the wireless operating device 60 is manually pressed. This allows the user, in particular, to activate an auxiliary heater or auxiliary air conditioning system of the motor vehicle 10 before even approaching the motor vehicle 10.Such activation typically indicates that a start of the motor vehicle 10 is imminent, as the user is activating the auxiliary heating or auxiliary air conditioning in order to drive off soon. This also justifies the activation of a start-up function for at least one of the sensors 31, 32.

[0035] As an alternative to immediate activation as described above, activation after a specified waiting time can also be implemented.

[0036] For the sake of readability, the term "at least one" has been partially omitted. If a feature of the technology disclosed here is described in the singular or indefinitely (e.g., the sensor(s), the transmitter(s), etc.), the plural form is also intended to be disclosed (e.g., the at least one sensor, the at least one sensor, etc.).

[0037] The foregoing description of the present invention is for illustrative purposes only and not for the purpose of limiting the invention. Various changes and modifications are possible within the scope of the invention and its equivalents.

[0038] List of reference symbols

[0039] 10 motor vehicle

[0040] 20 fuel cells

[0041] 25 Exhaust path

[0042] 31 first sensor

[0043] 32 second sensor

[0044] 40 Control device

[0045] 50 channels

[0046] 60 wireless control devices

[0047] 62 button

Claims

Claims 1 . Method for activating a start-up function of at least one sensor (31, 32) of a motor vehicle (10), the method comprising the following steps: - determining that a start of the motor vehicle (10) is imminent, and - In response to determining that a start of the motor vehicle (10) is imminent, activating the start-up function; wherein at least one group of equivalent sensors (31, 32) is present, and wherein, in at least one group, when the start-up function is activated, said start-up function is only activated for a portion of the equivalent sensors (31, 32) of the group.

2. Method according to claim 1, wherein in the case of immediately successive activations the start-up function is activated for different sensors (31, 32) of a group.

3. Method according to claim 1 or 2, wherein in the case of several successive activations the start-up function is activated according to a predetermined pattern among the sensors (31, 32) of a group.

4. Method according to one of the preceding claims, wherein in all activations always the same sensor(s) (31, 32) of a group are activated, but not all sensors (31, 32) of this group are activated.

5. Method according to one of the preceding claims, wherein sensors (31, 32) in which a start-up function is activated, Do not perform any measuring tasks while the start-up function is being executed.

6. The method according to any one of the preceding claims, wherein determining that a start of the motor vehicle (10) is imminent occurs in response to detecting an approach of a user to the motor vehicle (10).

7. The method according to claim 6, wherein the approach of a user to the motor vehicle (10) is detected by means of a transmitter (50) worn by the user.

8. The method according to any one of the preceding claims, wherein determining that a start of the motor vehicle (10) is imminent occurs in response to a user activating a function of the motor vehicle (10).

9. Method according to one of the preceding claims, wherein determining that a start of the motor vehicle (10) is imminent occurs in response to the motor vehicle (10) independently activating a function.

10. Method according to one of the preceding claims, wherein the start-up function is activated in only some of the sensors (31, 32) of a motor vehicle (10) in response to determining that a start of the motor vehicle (10) is imminent. 11 .Method according to one of the preceding claims, wherein End of the start-up function the sensor (31 , 32) or the sensors (31 , 32) into a measuring function.

12. Method according to one of the preceding claims, wherein the start-up function is or includes warming up the sensor (31, 32) or the sensors (31, 32).

13. Method according to one of the preceding claims, wherein one sensor (31, 32) or several sensors (31, 32) are designed as a hydrogen sensor.

14. Control device (40) for one or more sensors (31, 32), wherein the control device (40) is configured to carry out a method according to one of the preceding claims.

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