Patent Description:
The invention can be applied in heavy-duty vehicles, such as trucks, buses and construction equipment. The invention can also be applied in light-duty and medium-duty vehicles. Although the invention will mainly be described with respect to a heavy-duty vehicle, the invention is not restricted to this particular vehicle, but may also be used in other vehicles such as passenger cars.

In modern vehicles, the position of a pedal may be detected by a dedicated pedal position sensor. For example, there is a one sensor for the accelerator pedal, another sensor for the brake pedal and yet another sensor for the clutch pedal. As a driver presses a pedal, the associated sensor will detect the movement of the pedal and send a sensor signal to a control unit, and the control unit will then send an actuator signal to an associated actuator. An example of such a sensor is, for instance, a resistive type sensor using a potentiometer. A drawback of such a sensor is its degradation over time. In other words, it will become mechanically worn and will therefore become less accurate.

<CIT> discloses an infrared sensor mounted in the pedal which measures the distance from the pedal to an approaching foot of the driver. It also discloses another sensor that senses the distance between the pedal and a splashboard. While these sensors may reduce the risk of mechanical wear of the sensors and therefore reduce the risk of degradation over time, there is still room for improvement.

<CIT> discloses an imaged-based detection system, which may be implemented for a vehicle. The image-based detection system comprises one or more image sensors configured to receive images of a vicinity of a control, and one or more processors configured to identify within the images a control actuator and the control. A trigger action of the control actuator relative to the control is detected based on the images. According to the detected trigger action a switch is made from a normal control mode to a safety mode.

An object of the present invention is to provide system and a method which at least partly provide an improvement over the prior art. This and other objects are accomplished by a system and a method as defined in the accompanying independent claims. Some non-limiting exemplary embodiments are presented in the dependent claims.

The inventors have realized that by using a camera which captures an image of two or more pedals, which captured image may be analysed by a control unit, the positions of the different pedals may effectively be determined. Thus, multiple sensors may be eliminated by using a single image-capturing camera. In this way, the risk of mechanical wear is reduced. In addition, the number of components may be reduced, since a single camera can capture an image which includes more than one pedal, while the prior art IR sensor technology is based on measuring the time for a transmitted wave to propagate and be reflected back to the sensor, and therefore requiring one sensor for each pedal.

According to a first aspect of the invention, there is provided a system for controlling actuators based on pedal positions in a vehicle, the system comprising:.

wherein the control unit is configured to:.

By providing a camera which captures an image that shows two or more pedals, the control unit can control the associated actuators for all those pedal even though only one camera is used. For instance, if a driver presses the clutch pedal and the brake pedal at the same time, a control in a system of the present inventive concept would detect that both pedals have been pressed even though only one camera is used, as the camera and the resulting image provided by the camera covers both/all pedals.

It should be understood that the image provided by the camera to the control unit may suitably be in digital form, i.e. a digital image. Thus, the control unit may suitably analyse a digital image rather than an analogue image.

It should be understood that the actual controlling of the actuators, once the pedal positions have been determined, may be performed in any conventional way. Typically, the control unit may be configured to send an output/actuating signal to the respective actuator. For instance, if the control unit determines that the accelerator pedal has been pressed, then an accelerator output signal is sent to the actuator associated with the accelerator pedal. Similarly, a brake output signal and a clutch output signal, may in the event of the brake pedal and the clutch pedal being pressed, be send to a respective associated actuator. The actuators may be conventional actuators. For instance, the actuator associated with the accelerator pedal may comprise a motor that receives the output signal from the control unit, which motor moves a throttle valve to an appropriate position based on the output signal from the control unit.

As mentioned above, the control unit is configured to determine the current position of the pedal relative to a fixed structure in the vehicle or relative to a reference position of the pedal. A fixed structure may be any suitably structure that is intended to be still in the vehicle. For instance, such a fixed structure may be a base plate connected to the pedal. The pedal may be movably connected to such a fixed based plate. However, other fixed structures are also conceivable, such as a panel, rails, etc. The fixed structure may suitably be provided with a distinguishable point or area, which the control unit can identify in the provided image. Similarly the pedal may suitably be provided with a distinguishable point or area, which the control unit can identify in the provided image. In such cases, the control unit may analyse the image and determine the distance between the point on the pedal and the point on the fixed structure.

From the above it can be understood that, according to at least one exemplary embodiment, the camera is configured to capture an image containing two or more pedals in a vehicle, and also containing at least one fixed structure, and to provide the image to the control unit, wherein the control unit is configured to determine for each pedal, based on the provided image containing the pedals and the fixed structure, the current position of the pedal, and to control an actuator associated with the pedal based on the determined position.

Instead of comparing the position of the pedal relative to a fixed structure, the control unit may, in at least some exemplary embodiments compare the current position of the pedal relative to a reference position of the pedal. Such a reference position may, for instance, be the original non-pressed position of the pedal, i.e. the position of the pedal before it is pressed by a driver's foot. For example, when manufacturing the vehicle or when installing the system of the present invention in a vehicle, an initial reference image may be taken by the camera and stored in an electronic memory. Later on, in use, the control unit will be able to compare the initial reference image with new captured images to determine the position of each pedal.

The control unit may include a microprocessor, microcontroller, programmable digital signal processor or another programmable device. The control unit may also, or instead, include an application specific integrated circuit, a programmable gate array or programmable array logic, a programmable logic device, or a digital signal processor. Where it includes a programmable device such as the microprocessor, microcontroller or programmable digital signal processor mentioned above, the processor may further include computer executable code that controls operation of the programmable device.

According to at least one exemplary embodiment, for each pedal, the control unit is configured to:.

Thus, the control unit may search for a predefined point in the provided image, the predefined point being an identifier used for determining the position of the pedal. Such a predefined point or identifier may be a distinguishable structure in the main pedal material itself, or it may be an item, marking, etch that has been connected at a certain location of the pedal. The control unit detects the position of the predefined point (identifier) and determines its position in the image. The control unit can then, in some exemplary embodiments, compare this position in the image with the position of the fixed structure, and thereby calculate the position of the pedal relative to the fixed structure, and then control the actuator based on this calculation. In other exemplary embodiments, the control unit may compare the determined position of the predefined point with a reference position of the predefined point (the reference position being stored in an electronic memory), and thereby calculate the pedal position and control the associated actuator based on this calculation. Using two or more predefined points on each pedal, and determining the positions of those points, will provide more confidence in the calculations made by the control unit.

From the above, it should be understood that the image does not necessarily need to include the entire pedal. What is important in the above mentioned exemplary embodiments, is that at least the part of the pedal that presents the predefined point (identifier), is included in the image. Thus, in the context of this invention, it should be understood that the fact that the camera is configured to capture an image containing two or more pedals encompasses that the entire pedals are included in the image or portions of the pedals are included in the image. Furthermore, it may be conceivable that one pedal is fully included while only a portion of another pedal is included in the image.

According to at least one exemplary embodiment, the camera is configured to capture and provide a sequence of images, wherein for at least one of said pedals, the control unit is configured to:.

According to at least one exemplary embodiment, one of said pedals is a brake pedal, wherein the control unit is configured to send an emergency brake signal to a brake actuator associated with the brake pedal when the detected positional change per unit of time exceeds a predetermined threshold.

Thus, when the control unit detects a fast depressing of the brake pedal it will send an emergency brake signal to the brake actuator in order to urgently decelerate the vehicle. The predetermined threshold is suitably selected so that it is clearly separated from ordinary controlled braking under normal driving conditions, such as braking when approaching a red light or start/stop scenarios when driving through city traffic, etc..

According to at least one exemplary embodiment, said camera is a thermographic camera configured to capture and create images by using infrared radiation emitted from said pedals. This is advantageous because thermographic cameras do not require any ambient brightness and operate just as well at night as in daytime.

As has already been mentioned above, the position of the pedal may be determined in different ways, such as relative to a fixed structure, or relative to reference position of the pedal itself. This different exemplary options will briefly be discussed below.

According to at least one exemplary embodiment, at least one of the pedals is connected to a base plate, wherein said fixed structure comprises said base plate, wherein the control unit is configured to determine for said at least one of the pedals, based on the provided image, the position of the pedal relative to its connected base plate. Thus, the image captured by the camera may suitably contain both the pedal and the base plate. The control unit may therefore from a single image determine the distance between the pedal and the base plate. The control unit may suitably translate the distance into a certain actuator signal. For instance, in case of the pedal being an accelerator pedal, the smaller the distance, the larger the acceleration request. The correspondence between different distances and different requested output values to which the distances are translated may, for instance, be provided in a look-up table accessible by the control unit, or calculated by the control unit using a mathematical formula.

According to at least one exemplary embodiment, the system comprises an electronic memory in which a reference image is stored, the reference image containing said two or more pedals when they are in their respective non-pressed original positions, wherein the control unit comprises or has access to said electronic memory, wherein the control unit is configured to determine the position of each pedal by comparing the captured image provided by the camera with said reference image. This is advantageous as the control unit does not need to look for a fixed structure. Thus, this exemplary embodiment may advantageously be used for pedals without base plates, such as suspended type pedals. However, this exemplary embodiment may, of course, be implemented for any type of pedal, i.e. also for those connected to a base plate.

According to at least one exemplary embodiment, the camera is configured to capture an image containing an accelerator pedal and a brake pedal, wherein the control unit is configured to:.

Since the control unit receives an image that contains two or more pedals, such as the above exemplified accelerator pedal and brake pedal, the control unit may control the respective associated actuators in parallel, if needed. For instance, the captured image contains both the brake pedal and the clutch pedal, the control unit may from the received image determined that the driver has pressed both pedals and therefore actuates both the brake and the clutch actuator, respectively. The image captured by the camera may of course contain three pedals: accelerator pedal, brake pedal and clutch pedal, in which case the control unit may be configured to control all three associated actuators. For instance, according to at least one exemplary embodiment, the captured image further contains a clutch pedal, wherein the control unit is configured to send a clutch actuating signal to a clutch actuator based on the determined position of the clutch pedal.

In addition to controlling the actuators, in at least some exemplary embodiments, the control unit may, when analysing the received image from the camera, be configured to detect foreign objects in the pedal area, and issue a warning signal to alert the driver thereof. Such a warning signal may, for instance, be implemented as a visual warning on a display or a light turned on, etc. or as an audible warning such as a voice message or an audible tone, etc. or a tactile warning such as a vibration discernible by the user's hands, feet, or other body parts.

According to a second aspect of the invention, there is provided a vehicle. The vehicle of the second aspect comprises a system of the first aspect, including any embodiment thereof. The advantages of the vehicle according to the second aspect are largely analogous to the advantages of the system according to the first aspect, including any embodiment thereof.

According to a third aspect of the invention, there is provided a computer-implemented method for controlling actuators based on pedal positions in a vehicle, the method comprising:.

Some exemplary embodiments of the method of the third aspect are listed below.

According to at least one exemplary embodiment, the method comprises:.

According to a fourth aspect of the present invention, there is provided a computer program comprising program code means for performing the steps of the method according the third aspect, including any embodiment thereof, when said program is run on a computer. The advantages of the computer program of the fourth aspect are largely analogous to the advantages of the method of the third aspect, including any embodiment thereof.

According to a fifth aspect of the present invention, there is provided a computer readable medium carrying a computer program comprising program code means for performing the steps of the method according to the third aspect, including any embodiment thereof, when said program product is run on a computer. The advantages of the computer readable medium of the fifth aspect largely correspond to the advantages of the method of the third aspect, including any embodiment thereof.

According to a sixth aspect of the present invention, there is provided a control unit for controlling actuators based on pedal positions in a vehicle, the control unit being configured to perform the steps in the method according to the third aspect, including any embodiment thereof. The advantages of the control unit of the sixth aspect are largely analogous to the advantages of the method of the third aspect, including any embodiment thereof.

All references to "a/an/the part, element, portion, component, arrangement, device, means, step, etc." are to be interpreted openly as referring to at least one instance of the part, element, portion, component, arrangement, device, means, step, etc., unless explicitly stated otherwise. Further features of, and advantages with, the present inventive concept will become apparent when studying the appended claims and the following description. The skilled person realizes that different features of the present inventive concept may be combined to create embodiments other than those described in the following, without departing from the scope of the present inventive concept.

<FIG> illustrates a vehicle <NUM> in which a system according to at least one exemplary embodiment of the present invention may be implemented. In this example, the vehicle <NUM> is a heavy-duty vehicle in the form of a tractor unit. The tractor unit may, for instance, be powered by a propulsion system, such as including an internal combustion engine, electric motor, fuel cell engine, or a combination thereof. Although a tractor unit has been illustrated, it should be understood that the teachings of the present invention may also be implemented in other types of vehicles, such as busses, construction equipment and passenger cars. The illustrated vehicle <NUM> comprises a cabin <NUM> in which a driver may operate the vehicle <NUM>. The vehicle <NUM> comprises pedals which the driver may depress with his/her feet to accelerate or decelerate the vehicle. In embodiments in which the vehicle has a manual gear shift, a pedal may also be provided for actuating a clutch when the driver wishes to shift gears.

<FIG> is a schematic illustration of a system <NUM> according to at least one exemplary embodiment of the present invention. In <FIG> three pedals <NUM>, <NUM>, <NUM> are illustrated, however, the system <NUM> may also be implemented in vehicles having only two pedals. The pedals illustrated in <FIG>, may for example be an accelerator pedal <NUM>, a brake pedal <NUM> and a clutch pedal <NUM>. As conventional, when a driver presses a pedal, a corresponding actuator <NUM>, <NUM>, <NUM> will be activated, whereby the propulsion, acceleration, deceleration, gear-shifting, etc. may be controlled.

Although it is known to use a control unit which translates pedal sensor signals into actuating signals for controlling the corresponding actuators, the general inventive concept achieves it in a new and efficient way, eliminating the need for individual sensors for each pedal.

The system <NUM> of the present general inventive concept uses a single camera <NUM> for capturing an image <NUM> containing all the pedals <NUM>, <NUM>, <NUM> (or containing portions of all the pedals <NUM>, <NUM>, <NUM>). The captured imaged <NUM> is provided to a control unit <NUM> for analysis. Thus, the system <NUM> of <FIG> is a system <NUM> for controlling actuators <NUM>, <NUM>, <NUM> based on pedal positions in a vehicle. The system <NUM> comprises the control unit <NUM> and the camera <NUM>. The camera <NUM> may suitably be a thermographic camera, even though the inventive principle could be implemented with other types of cameras as well. The camera <NUM> is configured to capture an image <NUM> containing two or more pedals (in this example, three pedals <NUM>, <NUM>, <NUM>), and to provide the image <NUM> (suitably in the form of a digital image) to the control unit <NUM>. In its turn, the control unit <NUM> is configured to determine for each pedal, <NUM>, <NUM>, <NUM>, based on the provided image <NUM>, the current position of the pedal relative to a fixed structure in the vehicle or relative to a reference position of the pedal. Then, based on the determined position, the control unit <NUM> is configured to control the actuator <NUM>, <NUM>, <NUM> associated with the pedal <NUM>, <NUM>, <NUM>. Thus, the control unit <NUM> may be configured to send an acceleration signal <NUM>, based on the determined position to the accelerator pedal <NUM>, to the associated acceleration actuator <NUM>. Similarly, the control unit <NUM> may be configured to send a brake signal <NUM>, based on the determined position of the brake pedal <NUM>, to an associated brake actuator <NUM>. In embodiments in which a clutch pedal <NUM> is present and captured in the image <NUM> provided by the camera <NUM>, the control unit <NUM> may be configured to send a clutch actuating signal <NUM> to an associated clutch actuator <NUM> based on the determined position of the clutch pedal <NUM>.

<FIG> and <FIG> illustrates two different types of pedals. In <FIG> two pedals <NUM> are shown of suspended type. The two pedals <NUM> may be an accelerator pedal and a brake pedal. In other examples, there may be a third pedal as well, e.g. a clutch pedal. In <FIG> another type of pedal <NUM> is illustrated, wherein the pedal <NUM> is connected to a base plate <NUM>. A vehicle may suitably have two or more pedals of this type. The pedals <NUM>, <NUM>, <NUM> illustrated in the system <NUM> of <FIG> may be of either one of the types.

The base plate <NUM> in <FIG> represents a fixed structure which may conveniently be captured in an image together with the pedal <NUM>. For the suspended types of pedals <NUM> in <FIG>, it may be more appropriate to compare the captured image with a stored reference image, when the control unit determines the positions of the pedals <NUM>.

As illustrated in <FIG> as well as in <FIG>, each pedal may have one or more predefined points <NUM> which the control unit is configured to find in the image provided by the camera <NUM>. As exemplified in <FIG>, the predefined points <NUM> may be at a respective edge of the pedals <NUM>. However, another conceivable location may be the underside of the foot-receiving part of each pedal <NUM>. Yet another conceivable location may be at the long shank part that extends from the foot-receiving part of each pedal <NUM>. In either case, the camera <NUM> should be positioned so that it can capture all predefined points <NUM> in one image. As exemplified in <FIG>. in at least some exemplary embodiments there may be two (or more) predefined points <NUM> on each pedal <NUM> for the control unit to detect in the image provided by the camera <NUM>. This may improve the accuracy of the calculations made by the control unit.

When the control unit has identified the predefined points <NUM> in the image received from the camera <NUM> and determined their positions in the image, the control unit may, based on these determined positions, calculate the position of each pedal <NUM>, <NUM>. In the example of <FIG> the control unit would suitably calculate the position of each pedal <NUM> relative to their reference position. For instance, the control unit would suitably compare the positions of the predefined points <NUM> in the now captured and received image with their positions in a reference image (taken in an original non-depressed state of the pedals), which is suitably stored in an electronic memory accessible by the control unit. Thereby, the control unit can calculate the position of each pedal <NUM>. In the example of <FIG>, the captured image provided by the camera <NUM> would suitably also include the base plate <NUM> (i.e. a fixed structure). The base plate may suitably also have a predefined point <NUM>. By comparing the position of the predefined points <NUM> of the pedal <NUM> with the position of the predefined point <NUM> of the base plate <NUM>, the control unit can calculate to what extend the pedal <NUM> has been pressed.

With reference to <FIG>, as already discussed, irrespective of the type of pedals used, the camera <NUM> may suitably be configured to capture and provide a sequence of images to the control unit <NUM>. Suitably, the camera <NUM> continuously captures and provides images to the control unit <NUM> from the time the propulsion system of the vehicle is started/enabled. For each pedal <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, the control unit <NUM> may compare the position of the pedal in two or more of the images in said sequence of images to detect a positional change of the pedal. The control unit <NUM> may then control the associated actuator <NUM>, <NUM>, <NUM> based on the detected positional change of the pedal. For instance, for a brake pedal <NUM>, if the positional change per unit of time is very large (e.g. exceeding a predetermined threshold), then the control unit <NUM> may suitably send an emergency brake signal to the brake actuator <NUM> associated with the brake pedal <NUM>.

Turning now to <FIG>, some different steps of non-limiting exemplary embodiments of the computer-implemented method of the present invention are illustrated. Such a computer-implemented method may suitably be performed by one or more control units, such as the control unit <NUM> illustrated in <FIG> or <FIG>.

<FIG> illustrates schematically a method <NUM> in accordance with at least one exemplary embodiment of the present invention. More specifically, <FIG> illustrates a computer-implemented method <NUM> for controlling actuators based on pedal positions in a vehicle, comprising:.

<FIG> illustrates schematically a computer-implemented method <NUM> in accordance with at least another exemplary embodiment of the present invention. This exemplary embodiment may include all the steps S1-S3 of the method <NUM> and additionally include the illustrated steps S4-S6. Steps S4-S6 may actually be considered to represent substeps to step S2. Thus, the method <NUM> may comprise:.

<FIG> illustrates schematically a computer-implemented method <NUM> in accordance with yet another exemplary embodiment of the present invention. This exemplary embodiment may include all the steps S1-S3 of the method <NUM>, and additionally includes the illustrated steps S7-S9. Furthermore, the method <NUM> may additionally include the steps S4-S6 of method <NUM>. Thus, the method <NUM> may comprise:.

<FIG>schematically illustrates a control unit <NUM> according to at least one exemplary embodiment of the present invention. In particular, <FIG> illustrates, in terms of a number of functional units, the components of a control unit <NUM> according to exemplary embodiments of the discussions herein. The control unit <NUM> may be comprised in any vehicle disclosed herein, such as the one illustrated in <FIG>, and others discussed above. Processing circuitry <NUM> may be provided using any combination of one or more of a suitable central processing unit CPU, multiprocessor, microcontroller, digital signal processor DSP, etc., capable of executing software instructions stored in a computer program product, e.g. in the form of a storage medium <NUM>. The processing circuitry <NUM> may further be provided as at least one application specific integrated circuit ASIC, or field programmable gate array FPGA.

Particularly, the processing circuitry <NUM> is configured to cause the control unit <NUM> to perform a set of operations, or steps, such as the method discussed in connection to <FIG> and/or <FIG> and exemplary embodiments thereof discussed throughout this invention. Thus, the processing circuitry <NUM> is thereby arranged to execute exemplary methods as herein disclosed.

The control unit <NUM> may further comprise an interface <NUM> for communications with at least one external device such as the camera <NUM> and the actuators <NUM>, <NUM>, <NUM> discussed herein. As such, the interface <NUM> may comprise one or more transmitters and receivers, comprising analogue and digital components and a suitable number of ports for wireline or wireless communication.

Claim 1:
A system (<NUM>) for controlling actuators (<NUM>, <NUM>, <NUM>) based on pedal positions in a vehicle (<NUM>), comprising:
- a control unit (<NUM>),
- a camera (<NUM>) configured to capture an image (<NUM>) containing two or more pedals (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>) in a vehicle and to provide the image to the control unit, characterised in that the control unit is configured to:
• determine for each pedal, based on the provided image, the current position of the pedal relative to a fixed structure (<NUM>) in the vehicle or relative to a reference position of the pedal, and
• control, based on the determined position, an actuator (<NUM>, <NUM>, <NUM>) associated with the pedal (<NUM>, <NUM>, <NUM>).