IT201600071688A1 - Procedure and device for the diagnosis of collisions in traffic events involving a vehicle. - Google Patents

Description

"Procedure and device for the diagnosis of collisions in traffic events involving a vehicle"

DESCRIPTION

Technical Field

The present invention relates in general to methods and devices for collision diagnosis for a traffic event, and more specifically, but not exclusively, to the detection of the occurrence of a collision between a vehicle and another vehicle or object after the collision is verified.

Background

It is known to equip a road vehicle with a collision detection system designed to detect a potential collision with another vehicle or other object, and to avoid the collision by taking corrective action, for example by applying the brakes. Such a system can use one or more sensors to detect the proximity and relative movement of an object with which the vehicle may collide. Typical sensors that can be used for this purpose include radar, capacitive sensors, laser detection, and acoustic detection, which can be used with sensors to determine vehicle kinematics, such as accelerometers. Such sensors detect an object within a predefined field of view, typically with a forward facing field of view. The capacitive sensors known for this purpose have two or more electrodes mounted on the vehicle, and detect the proximity of objects in front of the electrodes by means of a variation of the mutual capacitance between the electrodes, caused by the effect of the object on the electric field between the electrodes. Typically, separate arrays of transmitting and receiving electrodes can be used to provide a defined forward facing detection zone. Since these systems are primarily designed to avoid collisions, they are not omnidirectional, so they cannot detect side or rear collisions without the use of additional sensors. Vehicles may have systems for detecting major collisions, such as systems for inflating airbags in a collision. However, existing collision avoidance systems have limited collision diagnosis capabilities, for example in detecting that a collision has actually occurred, such as a small-scale impact, and in particular existing systems do not allow omnidirectional detection. of a collision.

An object of the invention is to address at least some of the limitations of the prior art systems.

Synthesis

In accordance with a first aspect of the present invention, a method of generating a collision diagnosis for a traffic event involving a vehicle is carried out, the method comprising:

receiving an output from a self-capacitance sensor having a single electrode, the single electrode comprising at least part of the vehicle body;

comparing the received output with at least one threshold to generate interim collision detection data;

correlating interim collision detection data with additional traffic event data to produce correlation data; And

generation of the collision diagnosis based on related data.

An advantage of using a sensor with its own capacity having a single electrode, the only electrode comprising at least part of the vehicle body, is that it is possible to detect collisions in points all around the body of a car, so that the sensing is approximately omnidirectional, and in the fact that a simple and economical arrangement is obtained avoiding the use of additional electrodes or arrays of sensors.

An advantage of generating interim collision detection data, correlating interim collision detection data with additional traffic event data to produce correlation data, and generating collision diagnosis based on correlation data, consists in the fact that it is possible to reduce the percentage of false alarms of the collision diagnosis compared to the autonomous use of the car body as the only electrode of a sensor with its own capacity.

In an embodiment of the invention, the further data relating to the traffic event comprises data from at least one other sensor on the vehicle.

This allows for a more reliable collision diagnosis than would be obtained from the self-capacitance sensor or the other sensor or the other sensors alone.

Said at least one other sensor can comprise a location sensor, an acceleration sensor, a rotation sensor, a vibration sensor, a microphone and / or a vehicle status sensor. These can provide further convenient indications of a collision.

In one embodiment of the invention, the generation of the collision diagnosis comprises the generation of an alert signal. This allows an indication of a collision diagnosis to be provided to an operator.

In an embodiment of the invention, the method comprises sending a message which transmits the alert signal to a node of a data network external to the vehicle.

This allows an operator at a remote location from the vehicle to be alerted to the collision diagnosis.

In one embodiment of the invention, the method comprises storing in memory the interim collision detection data, the interim collision detection data including an output reception time from the self-capable sensor.

This allows for non-real-time processing of interim collision detection data.

In an embodiment of the invention, the further data relating to the traffic event comprise a time interval. This allows the collision diagnosis to include an indication if a collision occurred within the time interval.

In one embodiment of the invention, the interim collision detection data includes location data, the additional traffic event data includes a specific location, and the collision diagnosis includes an indication if a collision has occurred. at the specific location. This allows the collision diagnosis to include an indication if a collision has occurred at a specific location.

In accordance with a second aspect of the invention, a device is provided for generating a collision diagnosis for a traffic event involving a vehicle, the device comprising one or more processors and an associated memory arranged to cause the device to actuate the claimed process.

In an embodiment of the invention, the device comprises an oscillator having a terminal intended to be connected to at least part of the vehicle body, so as to use said at least part of the vehicle body as the only sensor electrode with its own capacity.

This has the advantage of providing an omnidirectional sensor.

In accordance with a third aspect of the invention, a vehicle is made comprising the claimed device.

Further features and advantages of the invention will become apparent from the following description of some exemplary embodiments of the invention, which are provided by way of example only.

Brief Description of the Drawings

Figure 1 shows a schematic diagram illustrating a vehicle comprising a device according to an embodiment of the invention connected to the vehicle body, the vehicle being in collision with another vehicle;

Figure 2 shows a schematic diagram illustrating the operation of the device for a collision diagnosis in an embodiment of the invention;

Figure 3 shows a schematic diagram illustrating the operation of the device for a collision diagnosis in an embodiment of the invention, in which further data is provided by a sensor;

Figure 4 shows a schematic diagram illustrating the operation of a device for a collision diagnosis in an embodiment of the invention, in which an alert signal is provided on the basis of the collision diagnosis;

Figure 5 shows a schematic diagram illustrating the operation of a device for a collision diagnosis in an embodiment of the invention, in which data representing a time interval and / or a location are correlated with provisional detection data collision stored in memory;

figure 6 shows a schematic diagram showing a sensor with its own capacity in an embodiment of the invention; And

Figure 7 shows a flow diagram of a method of generating a collision diagnosis for a traffic event involving a vehicle in an embodiment of the invention.

Detailed Description

By way of example, some embodiments of the invention will now be described in the context of generating a collision diagnosis for a traffic event involving a vehicle, in which the vehicle is a private car, but it will be understood that forms of embodiments of the invention may refer to other vehicles such as commercial vehicles, and that embodiments of the invention are not limited to the diagnosis of collisions with other vehicles, but may refer to other traffic events such as collisions of the vehicle with roadside objects, for example road infrastructure, trees or buildings, and with people and / or animals.

Figure 1 shows a vehicle 1 comprising a collision diagnosis device 4 according to an embodiment of the invention connected to the vehicle body 3. Vehicle 1 is shown colliding with another vehicle 2. A collision diagnosis for a traffic event involving the vehicle can be an indication, in real time or near real time, that a collision has occurred, or it can be a indication, based on stored data, that a suspected collision has indeed occurred within a specified time interval. The device 4 comprises a sensor with its own capacity with a single electrode which is adapted to use the vehicle body 3, or at least part of the vehicle body, as a single electrode of the sensor. In this way, the sensor detects the own capacity of the vehicle body. This provides a sensor with an approximately omnidirectional response, whereby collisions can be detected at points on each side of the vehicle, using a simple and inexpensive arrangement, avoiding the use of additional electrodes or arrays of sensors. The bodywork can be connected to an oscillator in the device, so that variations in the body's own capacitance change the operating frequency and / or amplitude of the oscillator. The mass of the oscillator is typically isolated from the car body to prevent short circuits of the oscillator signal. If the vehicle is in immediate proximity to or in contact with another object, such as another vehicle or a roadside object, the body's own capacity varies and changes the amplitude and / or frequency of the oscillator. The other object need not be metallic or electrically conductive; even if the other object is not conductive, the dielectric effect of the object will affect the apparent capacity of the vehicle body. Detecting a change in oscillator frequency and / or amplitude, or comparing a frequency and / or amplitude factor with one or more thresholds, may indicate that another object is in contact with the, or in the immediate vicinity of the vehicle bodywork. The device is connected to the bodywork at a convenient connection point, for example connection point 5. By contrast, known capacitive detector systems to avoid collisions use two electrodes mounted on the vehicle, separated from the vehicle body, to allow reliable detection. proximity of objects in front of the electrodes by a variation of the mutual capacitance between the electrodes, caused by the effect of the object on the electric field between the electrodes.

Figure 2 shows a functional block diagram which schematically illustrates the operation of a device according to an embodiment of the invention, in which a high percentage of false alarms, which could otherwise result from the use of the car body as the only electrode of a sensor with its own capacitance, is reduced by correlation with further data. An output is received, in a comparison functional block 7, by a sensor with its own capacity 6 having a single electrode comprising at least part of the vehicle body 3. The received output is compared with a threshold 8, or with more than one threshold, to generate interim collision detection data 9. The interim collision detection data 9 is correlated, in a correlation functional block 10, with further data 11 relating to the traffic event to produce correlation data, and a diagnosis collision 12 is generated on the basis of the correlation data. Generating interim collision detection data, correlating interim collision detection data with additional traffic event data to produce correlation data, and generating collision diagnosis based on correlation data, allow for reduce the false alarm rate of the collision diagnosis, or can mitigate the effects of a high false alarm rate, depending on the nature of the collision diagnosis.

As illustrated in the functional block diagram in Figure 3, the additional traffic event data may include data from at least one other sensor 13 on the vehicle, which can provide a more reliable collision diagnosis than would be obtained by use. of the own-capacity sensor or the other sensor or the other sensors by themselves. The other sensor or sensors may include, for example, a satellite navigation receiver, an acceleration sensor, a rotation sensor, a vibration sensor and / or a vehicle status sensor, which can provide further convenient indications. of a collision.

As illustrated in the functional block diagram in Figure 4, the generation of the collision diagnosis includes the generation of an alert signal 14, which allows an indication of a collision diagnosis to be provided, for example, to an operator, or to another electronic device. A message communicating the warning signal can be sent to a node of a data network external to the vehicle, so that, for example, an operator in a remote location from the vehicle can be warned of the collision diagnosis. This can be referred to as direct detection, as the collision diagnosis can be generated in near real time and can be triggered by an output of one or more sensors.

As illustrated in the functional block diagram in Figure 5, the interim collision detection data can be stored in memory 15, the interim collision detection data including the result of a comparison of the self-capacitance sensor output with one or more multiple thresholds together with a self-capable sensor output receive time, enabling non-real-time processing of interim collision detection data. Alternatively or additionally, the data representing the output of the self-capacitance sensor, rather than the provisional collision detection data, may be stored in memory 15, together with a receive time and / or location data, allowing a non-real-time processing of the data representing the sensor output at its own capacity. The further data relating to the traffic event may comprise a time interval 16, so that the collision diagnosis may include an indication as to whether or not a collision has occurred within the time interval. Alternatively or in addition, the interim collision detection data includes location data, the additional traffic event data includes a specific location, and the collision diagnosis includes an indication if a collision has occurred at the location specific. This can be referred to as reverse detection, as the collision diagnosis can be generated after a delay, which can last for days or weeks after the time interval, and can be triggered by an investigation after the event of a hypothesized collision. A relatively high rate of false alarms from a single electrode self-capacitance sensor may be tolerable when used for this purpose.

The device for generating the collision diagnosis can comprise one or more processors and an associated memory arranged for generating the collision diagnosis. The device 4 can be, for example, an electronic module mounted in a vehicle, as shown in Figure 1. Alternatively, parts of the device can be located remotely from the vehicle, for example in a remote data processing center. A radio or other connection, for example a cellular radio connection, can transmit, for example, the results of the correlation 10 to an external process where the collision diagnosis can be made.

Figure 6 shows an example of the realization of the sensor with its own capacitance with a single electrode comprising an oscillator. As illustrated, the sensor comprises an oscillator RC, comprising inverting amplifiers IC1A and IC1B, resistors R1 and R2 and a capacitor C1. The oscillator has a terminal 17 for connection to at least part of the vehicle body 3, so that the vehicle body is used as an electrode of the sensor with its own capacity. The capacitance of the vehicle body 3, together with the capacitance of C1, determines the frequency of oscillation of the oscillations of the oscillator. C1 is the discrete component capacitor used to define the base oscillation frequency, and the vehicle body 3, typically at a point on the metal structure of the vehicle, and connected to the common node between C1 and R1 / R2. Alternatively, the vehicle body can be connected to the other side of C1, at node 5 in Figure 6. The frequency change at the output of IC1C can be used to determine if an object is in contact with, or in the immediate proximity of the vehicle. In the example of the circuit shown in Figure 6, the oscillator is based on logic gates and therefore the amplitude of the output signal corresponds to the oscillation of the output voltage of the logic gates used, and, in this example, the amplitude can not be affected by the electrode capacity.

The mass of the oscillator is isolated from the mass of the vehicle, which is typically formed by the vehicle body, to prevent the common node between C1 and R1 / R2 being shorted to the tuned circuit ground through the vehicle body, as this it would stop the oscillations. The self-capacitance sensor power supply can be arranged to provide electrical isolation between the sensor circuit ground and the vehicle ground through the use of a floating power supply, which is not directly connected to the vehicle ground, such as a Switched Mode Power Supply (SMPS) or other similar techniques. Alternatively, or in addition, a floating power supply for the self-capacity sensor can be provided by a battery, which can be non-rechargeable or rechargeable. It is possible to use a solar panel to recharge a rechargeable battery.

The circuit shown in Figure 6 is an example of an oscillator that could be used in the self-capacitance sensor, but a variety of different oscillator types could be used. The principle behind the self-capacitance sensor is that each object has a certain electrical capacity of its own. Whenever an object comes into contact with, or is in immediate proximity to, another object, the ability of the first object is affected by the ability of the second object. Thus, the variation of an object's own electrical capacitance can be used as a means of detecting that another object was in contact with it, or in its immediate proximity. The variation of its own capacitance can be detected using an electric oscillator in which the frequency and / or the amplitude of the oscillation depends on the object's own electric capacity. Whenever a change in frequency and / or amplitude is observed, it is likely that this is caused by a change in its own capacity and consequently by the presence of another object in contact with, or in the immediate vicinity of, the object considered. . Large variations in self-capacitance can also cause the Barkhausen stability criterion not to be met, and therefore the electrical oscillation can be stopped completely until the objects are again sufficiently separated. A sensor with its own capacitance can be referred to as a single electrode capacitive sensor.

The proper capacity of an object depends on its size and shape, but is not significantly affected by the material of the object. An object made of a conductive material will have a capacity of its own which is only slightly higher than that of a similar object made of insulating materials. Thus, for example, an ideal conductive sphere will have its own capacitance, C given by: C = 4 π ε0R. If R = 1.5 m, C = 167 pF. By way of comparison, an ideal non-conductive sphere of the same size will have its own capacitance, C, given by: C = (10 π ε0R) / 3. For R = 1.5 m, C = 139 pF.

When two objects are in contact (not necessarily in electrical contact between electrically conductive parts) their own capacity approximately adds up, and this condition can be detected through a suitable electronic circuit. However, significant changes in an object's ability can also occur in the case of immediate proximity, but without actual contact, particularly when the other object is much larger (for example, a truck in the immediate vicinity of a car) . This could trigger false detections. Various types of electrical disturbances can also trigger false detections.

The change in self-capacitance can be detected by sensing the amplitude or frequency of the oscillations of an oscillator, which can include a tuned circuit, or by a combination of amplitude and frequency detection. The amplitude detection can, for example, be achieved by straightening the wave produced by the oscillator, and the rectified signal can be compared with one or more amplitude thresholds. Alternatively, the oscillator signal can be converted from the analog domain to a digital domain and thus one or more thresholds can be applied to the numerical results after the A / D conversion. Multiple thresholds can be used to produce detection with multiple confidence levels. The detection can also take place considering the derivative in time of the amplitude rather than the amplitude, for which the variations are highlighted.

The frequency detection can be carried out, for example, by means of a traditional frequency-voltage conversion circuit, and the detection can be carried out through appropriate voltage thresholds to allow detection with multiple confidence levels. The frequency can, for example, be measured by a traditional frequency measurement circuit which counts the number of cycles produced by the oscillator in a given period of time, typically less than a second, and advantageously less than 100 ms, and which it can be less than 50 ms, as vehicle collisions typically last between 50 and 100 ms. Detection can occur when the frequency change exceeds one or more predefined frequency change thresholds. Alternatively, a frequency measurement can be made indirectly by measuring a period, which is the duration of cycles produced by the oscillator. The period can be determined by averaging the duration of multiple cycles, but the number of cycles considered for the average should not be too large in order to provide meaningful results for events of short duration. For example, the average can be determined for less than 100 ms, or for less than 50 ms. Detection can occur when the period variation exceeds one or more predefined period variation thresholds.

The operation of a sensor with its own capacity has been described previously in terms of the variation of the own capacity of the vehicle body which acts as a single electrode connected to an oscillator. However, the operation of the same circuit can be described in terms of the car body which constitutes an antenna connected to the oscillator. In this case, the frequency and / or the amplitude of the oscillation depend on the characteristics of the antenna, and in particular on the impedance matching of the antenna. Whenever another object comes into contact with, or is in the immediate vicinity of, the antenna, the second object is electromagnetically coupled with the first object and actually becomes part of the antenna itself, thus modifying its electrical characteristics and therefore causing a variation in frequency and / or amplitude of the oscillation.

Thus, to detect the collision of a vehicle with other vehicles and, in general, with other objects, the capacity of the vehicle body is used as an element of an electric oscillator. Both conductive and non-conductive parts of the bodywork contribute to the inherent capability of the vehicle body. However, proximity to other vehicles as well as electrical disturbances can lead to false positives - the detection of collisions that did not actually occur. Therefore, in embodiments of the invention, the self-capacitance sensor can be combined with various auxiliary systems and features, such as additional sensors.

The results of the detection process can be recorded for evaluation at a later time, possibly in conjunction with data originating from other sensors. The results of the detection process can be stored in a memory which is located in the same location as the detector circuit. It is possible to retrieve data at a later time by using a data communication function. Alternatively or in combination, the results of the detection process can be transmitted almost in real time to external systems that store the data autonomously with respect to the sensor and the detector. The results of the discovery process can be made available to the outside world, in real time or retrieved from local memory at a later time, through wired and / or wireless connections. For example, a wired connection within the vehicle may include an RS-232, USB, or I2C connection. A wireless connection may include a short distance wireless connection, such as Bluetooth or WiFi, and / or a mobile network connection such as GSM, GPRS, UMTS and / or LTE.

For example, it is possible to use Bluetooth to transfer the detected data to the smartphone of the owner / driver of the vehicle, and then it is possible to use the GSM, GPRS, UMTS and / or LTE network connection of the smartphone to make the data available outside the vehicle. vehicle. A similar result can be achieved by using an electronic unit installed in the vehicle and which integrates Bluetooth and GSM, GPRS, UMTS and / or LTE communication features.

Figure 7 shows a flowchart summarizing the steps of an exemplary method of generating a collision diagnosis for a traffic event involving a vehicle in an embodiment of the invention. In a step S7.1, an output is received from a sensor with its own capacity having a single electrode comprising at least part of the vehicle body. In step S7.2, the received output is compared with a threshold to generate interim collision detection data. In an S7.3 step, the interim collision detection data is correlated with further traffic event data to produce correlation data, and in an S7.4 step, the collision diagnosis is generated based on the traffic event data. correlation.

A sensor with its own capacity with a single electrode can be used, typically in conjunction with other sensors and systems, to detect the collision of a vehicle with other vehicles or, in general, with other objects. Data from a collision diagnosis can be used to support the handling of a possible insurance claim that may be associated with the collision.

In a direct sensing process, for example as illustrated in Figures 3 and 4, sensing a change in own capacity can proactively trigger an alert signal that is ultimately sent to human operators, in real or near-time. in real time. Due to the likelihood of false positive detections related to the proximity of large vehicles and / or due to electrical disturbances, direct detection is preferably achieved by combining the output of the self-capacitance sensor with the output of other sensors so as to confirm that a real collision has occurred.

In a reverse detection process, for example as illustrated in Figure 5, the detection of a change in own capacity can simply trigger the recording of an event in the local memory of the sensor with own capacity and / or in the memory of external devices and systems. connected to the same sensor with its own capacity. There may not be an alert signal sent to operators in real time.

As a potential use of this system, the record can be consulted to determine if a change in proper capacity was detected in the date and time, or in a time interval, when an accident occurred according to a respective complaint, for example an insurance claim. The information can be used to verify the accuracy of the complaint. Since the recording can be consulted within a limited time window around the assumed time of the collision or accident, the presence of false positives can be tolerated, and therefore the reverse detection process can be effectively supported by the sensor with its own capacity even without no combination with other sensors.

As described herein, combining information from a single-electrode self-capacitance sensor with information from other sensors can increase the level of confidence that a collision has actually occurred. This is particularly convenient for supporting the direct detection process. The following sensors, in any combination, as well as other types of sensors, can be used for this purpose: time, location, and speed sensors such as GPS and / or GNSS, and / or network synchronization and geographic location based on GSM / GPRS / UMTS and / or LTE; acceleration sensors; rotation sensors, for example gyroscope-based sensors; vibration sensors, such as a microphone; and vehicle status sensors, such as braking force, throttle position, and steering angle sensors. The sensors can be installed on the vehicle for the specific purpose of supporting collision diagnosis together with the self-capable sensor, or they can be sensors originally installed on the vehicle, which can provide the corresponding data through the Control Area Network bus ( "Control Area Network" - CAN) of the vehicle and / or an OBD port.

The foregoing embodiments are to be understood as illustrative examples of the invention. It is to be understood that any feature described with reference to one of the embodiments can be used alone, or in combination with other described features, and can also be used in combination with one or more features of any other embodiment, or any combination of any other embodiment. Furthermore, equivalents and modifications not described herein can also be used without departing from the scope of the invention, which is defined in the appended claims.

Claims (17)

CLAIMS 1. A method of generating a collision diagnosis for a traffic event involving a vehicle, the method comprising: receiving an output from a sensor with its own capacity having a single electrode, the single electrode comprising at least part of the vehicle body; comparing the received output with at least one threshold for generating interim collision detection data; correlating interim collision detection data with additional traffic event data to produce correlation data; And generation of the collision diagnosis based on correlation data. The method according to claim 1, wherein the further data relating to the traffic event comprises data provided by at least one other sensor on the vehicle. The method according to claim 2, wherein said at least one other sensor comprises a location sensor. Method according to claim 2 or claim 3, wherein said at least one other sensor comprises an acceleration sensor. Method according to any one of claims 2 to 4, wherein said at least one other sensor comprises a rotation sensor. Method according to any one of claims 2 to 5, wherein said at least one other sensor comprises a vibration sensor. Method according to any one of claims 2 to 5, wherein said at least one sensor comprises a microphone. Method according to any one of claims 2 to 7, wherein said at least one other sensor comprises a vehicle status sensor. Method according to any one of claims 2 to 8, wherein the generation of the collision diagnosis comprises the generation of an alert signal. Method according to claim 9, comprising sending a message communicating the alert signal to a node of a data network external to the vehicle. Method according to any one of the preceding claims, comprising storing the provisional collision detection data in memory, the provisional collision detection data comprising an instant of receiving the output from the sensor with its own capacity. Method according to claim 11, wherein the further data relating to the traffic event comprises a time interval. The method according to claim 12, wherein the collision diagnosis comprises an indication of whether a collision has occurred within the time interval. The method according to claim 12 or claim 13, wherein the interim collision detection data comprises location data, the further traffic event data comprises a specific location, and wherein the collision diagnosis comprises a indication if a collision has occurred at the specific location. 15. Device for generating a collision diagnosis for a traffic event involving a vehicle, the device comprising one or more processors and an associated memory arranged to cause the device to carry out the method according to any one of claims 1 to 14 . 16. Device according to claim 15, the device comprising an oscillator having a terminal intended to be connected to at least part of the vehicle body, so as to use said at least part of the vehicle body as a single electrode of the sensor with its own capacity. 17. A vehicle comprising a device according to claim 15 or claim 16.