GB2498833A

GB2498833A - Ultrasonic gesture recognition for vehicle

Info

Publication number: GB2498833A
Application number: GB1221465.6A
Authority: GB
Inventors: Andreas Eisele
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 2011-11-29
Filing date: 2012-11-28
Publication date: 2013-07-31
Anticipated expiration: 2032-11-28
Also published as: FR2983308B1; DE102011087347A1; DE102011087347B4; FR2983308A1; GB201221465D0; GB2498833B

Abstract

A vehicle carries one or more ultrasonic sensors, wherein the ultrasonic sensor emits and receives ultrasonic signals depending on at least one operating condition of the vehicle. A control unit calculates, from signal transit-times of reflected ultrasonic signals, distances from objects in the surround field of the vehicle, and compares changes of signal transit-times with stored changes of signal transit-times corresponding to specific user-defined gestures. If the measured and stored transit times correlate, at least one actuator is driven to open a car door such as the tail-gate (boot, trunk). Different sensors can open different doors. The user can be recognised by a video camera, and the system only operated when the driver is near the vehicle. A radio key may also be used.

Description

Description Title

Process for controlling at least *one actuator on the basis of changes of signal transit-time of at least one ultrasonic sensor The invention takes as*its starting-point a process and an apparatus for an assistance system of a vehicle with at least one ultrasonic sensor, according to the precharacterising portion of the independent claims.

State of the Art From DE 10 2008 025 668 Al a process and an apparatus are known for operating a vehicle-closing device. Via various sensors of the vehicle the approach of potential vehicle occupants is established. When a potential vehicle occupant is present, a door, sliding door or hinged cover of the vehicle is opened if a response of the potential vehicle occupant is detected. Depending on the embodiment, a vehicle dobr is opened completely via an actuator or is only opened so far that it can be opened, for example, by an elbow of the potential vehicle occupant.

From DE 10 2004 005 225 Ala process and an apparatus are known for warning a driver of the opening of a door. For the purpose of detecting obstacles in the opening region of a door, ultrasonic sensors can be utilised which are also already present for a parking-assistance system.

From DElO 2006 001 666 Al a ptocess and an apparatus are known for the purpose of checking closing hinged covers, in particular automatically actuated boot lids of a motor vehicle. Obstacles in the opening region are registered via sensors operating capacitively. The closing of a hinged cover may be brought about via a gesture, whereby use may be made, inter alia, of ultrasonic sensors for the purpose of registration.

Disclosure of the Invention

Advantages of the Invention -

-

The procedue according to the invention with the * characterising features of the independent claims has, in contrast, the advantage that concordances are recognised by comparing changes of signal transit-time in relation to at least one ultrasonic sensor of a vehicle with at least one suitable change of signal transit-time, whereby advantageously a periodically fluctuating change of signal transit-time is assigned to a swaying back and forth of an object by way of gesture of a person located in the surround field of the vehicle, and whereby, depending on the gesture, at least one actuator is driven.

Further advantageous embodiments of the present invention are the subject-matter of the dependent claims.

A periodically fluctuating change of signal transit-time is, for example, a distance of an object within the detection range of at least one ultrasonic sensor of a vehicle, the at least one change of signal transit-time having been stored in a memori of a control unit. An actuator is,. for example, a closing element for opening and/or closing a tailgate of the vehicle.

Advantageously an evaluation of the sensor data of an ultrasonic sensor is effected independently of sensor data of other ultrasonic sensors, for example by filtering the sensor data. As a result, the sensor data can be used by different ultrasonic sensors for the purpose of driving different actuators. Accordingly, a person located in the surround field of the vehicle is able to drive various actuators with only one gesture, by the person performing the gesture within the detection range of ultrasonic sensors that have been assigned to particular actuators.

The person locaed in the surround field of the vehicle can, for example, open and/or close left or right doors by a gesture in front of an ultrasonic sensor of a vehicle that has been fitted on the left or right side, respectively, of the vehicle in a bumper of the vehicle, and can open a boot by the same gesture within the detection range of ultrasonic sensors that have been fitted centrally in a bumper.

In a further embodiment, the sensor data from other ultrasonic sensors, for example in the form of cross-echoes, may be drawn upon for the purpose of calculating changes of signal transit-time, whereby gestures that are performed within the detection range of several ultrasonic sensors are advantageously recognised by this means.

In a further embodiment, the user can freely define gestures for controlling at least one actuator of the vehicle. Consequently the ease of use for the user is enhanced, since he/she can choose motions that are easiest for him/her.

By virtue of the free definition of gestures, in a further embodiment the person within the detection range of an arbitrary ultrasonic sensor is able to drive a particular actuator by a gesture assigned to this actuator.

On the basis of, for example, a radio key that a person located in the surround field of the vehicle is carrying, or by virtue of further sensors on the vehicle, such as a video camera for example, the control unit recognises that the driver is in the vicinity of the vehicle.

Advantageously the comparison of the changes of the signal transit-times is carried cut only when the driver is in the vicinity. This prevents, for example, a battery of the vehicle from discharging in the parked state of the vehicle and making a restart of the vehicle imposible.

Additionally, further operating conditions -such as, for example, a stopping of the engine of the vehicle -can additionally be examined.

With a view to more precise recognition of the gestures, use may additionally be made of a camera fitted tothe vehicle in addition to the ultrasonic sensor. In order in poor lighting conditions to ensure a reliable recognition by the camera, for.example a reversing camera, use may be made of an additional light-source. By way cf additional light-source, use is made of an LED that emits light in the visible region, an infrared LED and/or a registration-plate illumination of thevehicle.

The apparatus according to the invention can be used directed both forwards and backwards on a vehicle.

Brief Description of the Figures

Exemplary embodiments of the invention are represented in the drawing and elucidated in more detail in the following

description.

Shown are: Figure 1 a schematic representation of an emboditnent of an apparatus according to the state of the art for ascertaining objects; Figure 2a a schematic representation of a first embodiment of the present invention for registering changes of signal transit-time of at least one ultrasonic sensor; Figure 2b a schematic representation of a second embodiment of the present invention for registering changes of signal transit-time of at least one ultrasonic sensor; Figure 2c a schematic representation of a third embodiment of the present invention for registering changes of signal transit-time of at least one ultrasonic sensor; Figure 3 a sketch for an example of a sequence of * motions of an object as basis of the process * according to the invention; Figure 4a a schematic representation of -an example of a * signal form as basis of the process according * -to the invention, in which an object is moved in temporally limited manner approximately with the same frequency and amplitude iz a registered region along the vehicle axis; Figure 4b a schematic representation of an example of a signal form as basis of the process according to the invention, in which an object is firstly moved approximately with the same frequency and amplitude and then with a numerically changed amplitude in a registered region along the vehicle axis; Figure 4c a schematic representation of an example of a signal form as basis of the process according to the invention, in which an.object is moved between a non-registered second region and a first registered region at right angles to the vehicle axis; Figure 5 a schematic representation of an embodiment of the apparatus according to the invention, in which an object is moved between a registered second region and a first registered region at right angles to the vehicle axis:

Detailed Description of the Exemplary Embodiments

In all the Figures, identical reference symbols denote the same articles.

Figure 1 shows an embodiment of an apparatus for ascertaining objects according to the state of the art.

A vehicle (101) includes at least one control unit (102) Data are madeavailable to the control unit (102) from at least one sensor (104). Further sensors (104 (1), 104 (2), 104 (n)) may be present. The sensor data may be communibated to the control unit (102) directly via an interface or alternatively via a bus system such as, for example, a CAN bus. The control unit contains at least one memory (106) for storing and processing the sensor data, the kinematic operating data and the vehicle data. The control unit (102) drives at least one actuator (103) Further actuators (103 (1), 103 (2), ... 103 (ra)) may be, for example, a starter or a closing element. The vehicle (101) and the control unit (102) may also exhibit further interfaces (107), for example for the interaction witha driver in the form of queries, and prompts.

The apparatus represented in Figure 2a includes, in a first embodiment, simplified in a top view, an ultrasonic sensor (4 (1)) with an acoustic acceptance angle (8 (1) ) . The distances dmin and dmax specify a minimal and maximal detection distance, respectively, of the ultrasonic sensor (4 (1)), i.e. the minimal and maximal distance of an object from the ultrasonic sensor (4 (1) ) , at which a distance from an object can be calculated correctly on the basis of reflectedsignals.

With the aid of the at least one ultrasonic sensor (4 (1) ) objects can be detected. For this purpose, signals are transmitted and received by the at least one sensor (4 (1)), and, from the signal transit-times, ranges are calculated and space coordinates relating to the objects are ascertained. The emitted signals are represented as half-waves (5 (1)) in Figure 2a.

A first region (6) is delimited by the minimal distance and a distance (db) *stored in a memory (106) of the control unit (102). A second region (7) is situated outside a maximal detection distance. By means of the regions (6) and (7) , the regions within which signal transit-times are taken into account can, for example, be defined.

In a second embodiment, which is shown in Fig. 2b, a first region (6) is likewise delimited by the minimal distance dun and a distance (db) stored in the memory (106) of the control unit (102) . A second region (7) is situated outside the acceptance angle of the ultrasonic sensor (4 (1)), i.e. an object within the second region (7) is not recognised by the ultrasonic sensor (4 (1) Fig. 2c shows a third embodiment, in which a first region (6) is defined by the minimal detection distance of the ultrasonic sensor (4 (1)) and a distance (db) stored in the control unit, the stored distance being smaller than the maximal distance dmax. The second region (7) is delimited approximately by a distance of the object d0hj from the vehicle and a value stored in the memory (106) of the control unit (102) This value may be an absolute distance from the ultrasonic sensor (4 (1) ) . Alternatively, the value may, for example, represent a width of theregion, so that the region is delimited by the minimal detection distance dmjn of the ultrasonic sensor (4 (1)) and by the sum of the distance of the object dobi from the vehicle and the value stored in the memory (106) of the control unit (102) Figure 3 shows an embodiment with two superposed regions (6) and (7). A control uni (1) of a vehicle (9) possesses at least one ultrasonic sensor (4) The ultrasonic sensor is advantageously an ultrasonic sensor Lhat has already been provided for a parking-assistance system.

Depending on further operating conditions, distances (dobi) from objects (10) in the surround field of the vehicle (9) are calculated. For this purpose the ultrasonic sensor (4) emits signals. On the basis of the received signals the control unit (1) calculates distances (dOb) from objects (10) . The control unit (1) compares changes of signal transit-times over time with changes of signal transit-times stored in the control unit (1) . In the case of a concordance, at least one actuator is driven.

fly means of the regions (6) and (7) , the regions within which signal transit-times are taken into account can, for example, be defined. For instance, an oscillation back and forth of an object without change of the regions (6) and (7) with small amplitude can be ignored as a gesture.

In Figure 3 an oscillating of an object (10) albng the vehicle axis, for example, is recognised. In a position of rest, the object (10) is located within a second region (7) . In the course of the motion of the object along the vehicle axis the object is firstly located within the second region (7) and isthen, for example, moved in the direction of the vehicle (9) . As a result, the object is no longer located in the second region (7) but is only located in the first region (6) . In the bourse of a subsequent motion contrary to the direction of the vehicle the object is moved through the second region (7) before the object is once again only in the first region (6) . The control unit (1) compares the changes of signal transit-time with the changes of transit-time stored in the control unit (1) . In Figures 4a, 4b and 4c diagrams are represented, whereby on the vertical axis the calculated distances dOb of an object between the minimal detection distance dmjn and the maximal detection distance drnax of the ultrasonic sensor have been plotted over a time axis. Moreover, the first.

region (6) and the second region (7) have been drawn in.

In the diagrams a possible calbulated signal forth of distances from objects in the surround field of the vehicle is represented over time. On the time axis, two markers (tl, t2) have furthermore been drawn in which show the temporalregion within which the control unit has recognised a concordance with signal forms stored in the control unit.

The diagrams in Figures 4a and 4b represent a posible signal form when an object (10) is moved, for example, as in Figure 3. The signal form in the diagram from Figure 4a shows within the two temporal markers, for example, a three-times-repeated oscillating back and forth of the object (10) along the vehicle axis.

From the diagram it is evident that a second region (7) is delimited approximately symmetrically with respect to a distance of the object dobj from the vehicle and by dimensions of the object. The maximal displacement of the object lies in a first region (6) which, for example, is delimited by the minimal and maximal detection distances dmin and dmax, respectively. The diagram in Figure 4b shows, for example, a twice-repeated oscillating forwards in the vehicle direction, followed by a simple oscillating backwards of the object (10) along the vehicle axis. Here too, there is a first region (6) and a second region (7), within which the signal form moves.

The diagram in Figure 4c shows a possible signal form which arises when an object from a region that cannot be registered by the ultrasonic sensor penetrates into the region of the acceptance angle of the ultrasonic sensor. A S first region (6) is delimited by the minimal detectipn distnce d1 and a value stored in the control unit. A second region (7) lies outside the maximal detection distance dma and/or outside the acceptance angle of the ultrasonic sensor. A signal formof such a type is brought about, for example, by a motion at right angles to the vehicle axis. In Figure 5 a possible embodiment of the present invention is represented in a top view, not true to scale. In a rear bumper (12) of a vehicle four ultrasonic sensors (4 (1) to 4 (4) ) have been fitted. These have a specific acceptance angle; for example, sensor (4 (3) possesses an acceptance angle (8 (3) ) and transmits and receives ultrasonic signals (5 (3)). For the other sensors a corresponding labelling has been dispensed with, with a view to better clarity.

In Figure 5 a person (11) located in the surround field of the vehicle, with an object (10) in his/her right hand, is standing in front of the rear bumper. On the basis of, for example, a radio key that the person located in the surround field of the vehicle is carrying, *or by virtue of further sensors on the vehicle, such as a video camera for example, the control unitrecognises that, for example, a driver is in the vicinity of the vehicle. Additionally, further operating conditions, sucH as stopping cf the engine for example, can be examined. The ultrasonic sensors (4 (1) to 4 (4)) now emit ultrasonic signals and communicate the measured signal transit-times to the control unit (1) via the at least one interface (3) -12--As is evident from Figure 5, the object (10) is moved at right angles to the vehicle axis by the person (11) located

in the surround field of the vehicle. This motion

generates a signal form as represented in exemplary manner in Figure 4c. The control unit (1) drives at least one actuator (13) via the interface (3) if, for example, a change of signal transit-time has been recognised that corresponds to a change of signal transit-time stored in a memory (2) in the control unit (1) By way of actuator (13), a closing element of a tailgate, of a bonnet, of a door, of a sliding roof, and/or hydraulic elements, for example, is/are driven.

Claims

<claim-text>Claims 1. Process for an assistance system of a vehicle with at least one ultrasonic sensor, wherein the ultrasonic sensor emits and receives ultrasonic signals depending on at least one operating condition, wherein a control unit calculates, from signal transit-times of reflected ultrasonic signals, distances from objects in the surround field of the vehicle, characterised in that the control unit compares changes of signal transit-times with stored changes of signal transit-times, whereby in the event of a concordance with at least one stored change of signal transit-time at least one actuator is driven.</claim-text> <claim-text>2. Process according to Claim 1, characterised in that a comparison of the changes of the signal transit-times with stored changes of signal transit-times is undertaken when a distance of the object in the surround field of the vehicle during the changes of the signal transit-times lies approximately within a first region and a further distance of the object lies approximately within a second region in the surroundfield of the vehicle.</claim-text> <claim-text>3. Process according to one of the preceding claims, characterised in that changes of the signal transit-times correspond to a succession of changes of signal transit-times stored in the control unit.</claim-text> <claim-text>4. Process according to one of the preceding claims, characterised in that changes of the signal transit-times correspond substantially to a periodic sequence with a frequency stored in he control unit and/or to a signal form stored in the control unit.</claim-text> <claim-text>5. Process according to one of the preceding claims, S characterised in that the first region is delimited by a minimal detection distance of the ultrasonic sensor and by a maximal distance from the ultrasonic ensor, stored in the control unit, *and the second region lies outside a maximal detection distance and/or outside the acceptance angle of the ultrasonic sensor.</claim-text> <claim-text>6. Process according to Claim 4, characterised in that the first region is defined by a minimal detection distance of the ultrasonic sensor and a maximal distance stored in the control unit, and the second region is delimited by approximately the distance of the object from the vehicle at the start of the periodic sequence and/or of the stored signal form.</claim-text> <claim-text>7. Process according to one of the preceding claims, characterised in that a gesture of a person located inthe surround field of the vehicle is assigned to astored change of signal transit-time.</claim-text> <claim-text>8. Process according to Claim 7, characterised in that the gesture of the person located in the surround field of the vehicle corresponds to an oscillating back and forth of the object perpendicular to, along and/or diagonally relative to the detection direction of the ultrasonic sensor.</claim-text> <claim-text>9. Process according to Claim 7 or 8,. characterised in that with a view to more precise recognition of the * gestures use is additionally made of a camera fitted to *the vehicle in addition to the ultrasonic sensor.</claim-text> <claim-text>* 10. Process according to Claim 9, characterised in that with a view to more precise recognition of the gestures in poor lighting conditions use is made of an additional light-source in addition to the ultrasonic sensor and the camera fitted to the vehicle.</claim-text> <claim-text>11. Process according to one of the preceding claims, characterised in that the camera that is present is a reversing camera and the additional light-source is an LED that ethits light in the visible region, or an infrared LED.</claim-text> <claim-text>12. Apparatus for an assistance system of a vehicle with at least one ultrasonic sensor, wherein the ultrasonic sensor emits and receives ultrasonic signals depending on at least one operating condition, wherein a control unit calculates, from signal transit-times cf reflected ultrasonic signals, distances from objects in the surround field of the vehicle, characterised in that the control unit compares changes of signal transit- * times with stored changes of signal transit-times, whe±eby in the event of a concordance with at least one stored change of signal transit-time at least one actuator is driven.</claim-text> <claim-text>13. Apparatus according to Claim 12, characterised in. that the at least one actuator is a closing element of a * boot lid and/or of at least one door of the vehicle.</claim-text> <claim-text>14. Computer program with program-code means in order to implement all the steps of a process according to one of Claims 1 to 1]. when the computer program is executed on a computer or on an appropriate arithmetic unit.</claim-text> <claim-text>15; Computer-program product with program-code means that have been stored on a computer-readable data carrier; in order to implement all the steps of a process according to one of Claims 1 to 11 when a computer program according to Claim 14 is executed on a computer or on an appropriate arithmetic unit.</claim-text> <claim-text>16. A process for an assistance system of a vehicle substantially as herein described with reference to the accompanying drawings.</claim-text> <claim-text>17. Apparatus for an assistance system of a vehicle substantially as herein described with reference to the accompanying drawings.</claim-text>