WO2012080799A1

WO2012080799A1 - Collision early warning system and method

Info

Publication number: WO2012080799A1
Application number: PCT/IB2011/002974
Authority: WO
Inventors: Nolan Van Heerden
Original assignee: Ikubu Cc
Priority date: 2010-12-13
Filing date: 2011-12-08
Publication date: 2012-06-21

Abstract

A warning system (1) for use by a road user, typically a pedestrian or cyclist, is provided. The warning system (1) includes a sensor (3) capable of sensing the presence and movement of objects in a direction not ordinarily in the field of view of the road user, and an electronic processor (5) capable of identifying objects approaching the road user from that direction and calculating a level of threat associated with objects approaching the road user. The system also includes a warning device (8) configured to receive control signals from the processor (5) and to produce a warning signal to the road user proportional in intensity to the level of threat calculated by the processor (5).

Description

COLLISION EARLY WARNING SYSTEM AND METHOD

FIELD OF THE INVENTION This invention relates to a warning system and method for detecting and warning road users other than those travelling in motor vehicles, for example cyclists, construction workers, recreational road users and other pedestrians, of impending danger approaching from a direction not in the road user's normal field of vision such as from the rear. The system and method are particularly suited for use on bicycles but may be used by any road users typically travelling along the edges of roads otherwise predominantly used by automobiles.

The term "vehicle" as used in this specification mostly refers to bicycles but, where appropriate, should be widely construed to include other types of vehicles such as motorbikes or other smaller transport means which may or may not be self-propelled. The term may also include other non-motorised vehicles such as animal drawn carts, push cards, perambulators and the like. The term should be distinguished from the term "motor vehicle" or "automobile" which will be used to refer to larger, typically enclosed, vehicles and passenger vehicles such as cars, taxis, trucks, vans and buses.

In addition, the term "road user" should be interpreted to specifically exclude operators of motor vehicles.

BACKGROUND TO THE INVENTION

Cycling, in both its on- and off road varieties, is a sport that has enjoyed marked growth in recent years. As such, the number and frequency of cyclists cycling along public roads has also increased substantially. An unfortunate result of this increase has been the associated increase in collisions between motor vehicles and bicycles. Due to the general lack of protection afforded cyclists during these collisions, cyclists involved in these collisions incur severe, often fatal, injuries while the motorists are generally unharmed. Many public roads do not have dedicated cycle lanes, nor do they have adequate shoulder sections where cyclists can ride beside the road surface generally used by motor vehicles. As a result, cyclists are forced to keep to the outer edges of road surfaces so as to allow motor vehicles to pass them, mostly at much higher speeds. These outer edges of road surfaces are, however, often in a bad condition, have irregular surface coverings or could be in the process of fragmenting, thus forcing the cyclists to cycle somewhat away from the edges towards the smoother, inner surfaces in order to avoid dangerous holes, loose earth, debris and other obstacles that may harm the bicycle or cause the cyclist to lose control of the bicycle and fall - possibly in front of traffic.

Bicycles are also typically not fitted with rear view mirrors such as are fitted to most motor vehicles and motorbikes. Even though such rear view mirrors are available for bicycles they are generally clumsy and appear awkward. This means that a cyclist is generally not able to see what is approaching him or her from behind and needs to rely solely on hearing or light from the incoming motor vehicles in low light conditions. Bad weather conditions such as wind or general background or road noise, however, means that hearing alone is also not a reliable way of warning the cyclist that a motor vehicle is approaching from behind. To add to this, it has become commonplace for cyclists to use personalized audio players that make use of earphones while cycling. This essentially eliminates hearing as a method of warning and substantially increases the cyclist's risk of being hit by an approaching motor vehicle from behind. Deaf or hearing impaired cyclists are naturally also at greater risk. From a motorist's perspective, cyclists are often not very visible and hence in greater danger of being hit. This is particularly true in low light conditions such as at dawn and dusk, which also happen to be preferred cycling times for cyclists due to the associated lower temperatures at these times of the day. It also frequently happens that cyclists unexpectedly swerve out to avoid obstacles or surface irregularities and motorists are unable to react in time in order to avoid hitting them. Motorists also often misjudge the space required to pass cyclists cycling on the side of the road and end up hitting or simply clipping a cyclist's handle bars or body, often having disastrous consequences for the cyclist.

A number of retrofittable devices have been developed to increase cyclist visibility to motorists but almost none of these are aimed at forewarning the cyclist of danger approaching from the rear or other directions not in the cyclist's direct field of vision. These retrofittable devices include passive reflectors, reflective clothing, electrical lighting which may be either battery operated or driven by dynamos that engage the bicycle wheels, mirrors, and more recently Light Emitting Diodes (LEDs) that are typically battery operated, to name but a few. These devices, however, suffer from a variety of disadvantages including limited visibility, clumsiness, difficulty of installation, the fact that they are unintelligent and, most importantly, in that they are aimed at warning or notifying motorists of the cyclist's whereabouts but do not provide any warning to the cyclist of danger approaching him or her from the rear. Where rear bicycle lights are provided they are typically not very bright, largely in an attempt to conserve battery life.

Another example of an attempt at a warning system that the applicant is aware of utilises a video camera directed towards the rear of the bicycle and image recognition techniques to identify vehicles that may pose a potential threat to the cyclist. The system utilizes an audible warning signal to inform the cyclist of the potential danger. These systems, however, suffer from the disadvantages that they are generally expensive, unwieldy, difficult to operate, sensitive to environmental and harsh physical conditions and in general are not effective in very bright or low light conditions. In addition, they do not provide any warning to the approaching motor vehicles and are still not usable by deaf or hearing impaired users. Solutions have also been proposed in which the video camera relays the recorded images to a video screen which is mountable to the bicycle's handle bars, thereby providing the cyclist with a rear view. These solutions, however, suffer from the same disadvantages. The problems mentioned above are, however, not only limited to cyclists and accidents involving motor vehicles and pedestrians, and other recreational and commuting road users are also common.

SUMMARY OF THE INVENTION

In accordance with this invention there is provided an early warning system for a road user comprising a sensor configured to be installed such that its field and range of detection covers at least one direction not ordinarily in the field of view of the road user and wherein the sensor is adapted to sense the presence of objects within the field and range of detection, a warning device configured to be installed so as to be capable of providing a warning signal to the road user, and an electronic processor for operating the warning device, potentially by means of a controller, based, at least to some extent, on information developed from data received from the sensor, the sensor being capable of developing data from which at least the location and velocity relative to the sensor of objects within its field and range of detection can be derived and wherein the electronic processor is configured to determine a level of threat posed by one or more of the objects within the field and range of detection to the road user, such threat potentially including a likelihood of a colliding with the road user, and to provide an output to the controller for controlling the warning device to produce a warning to the operator dependent, at least to some extent, on the level of threat and/or the likelihood of a collision occurring.

Further features of the invention provide for the road user to be an operator of a vehicle; for the sensor to be a radar sensor configured to be installed on the vehicle, alternatively for it to include attachment means for securing it on the person of the road user; for the vehicle to be a bicycle; for the direction to be the rear of the road user; for the warning device to be a visual indicator configured to be installed so as to be in a dominant field of vision of the road user, in the case of the road user being a cyclist preferably on the handle bars of the bicycle; for the visual indicator to be adapted to indicate varying degrees of warning dependent on the level of threat as determined by the electronic processor; for the visual indicator to be an array of light emitting diodes (LEDs); and for the output to cause the controller to activate a larger number of LEDs in response to a higher level of threat and a smaller number of LEDs in response to a lower level of threat.

A still further feature of the invention provides for the warning device to be a mechanical or electrical actuator including an attachment formation for removably attaching it to the person of the road user.

Still further features of the invention provide for the electronic processor to include a computer or microprocessor programmed to provide an output on the basis of computational or artificial intelligence optionally in combination with one or more appropriate algorithms; and for the output to be adapted to automatically operate said controller.

Yet further features of the invention provide for the system to include a secondary warning device adapted for installation with the sensor and orientated in substantially the same direction as the sensor for providing warning signals to objects approaching the road user from the direction; for the secondary warning device to be a light source; for the light source to be at least one but preferably a collection of LEDs; for the processor to be adapted to control the secondary warning device so as to emit warning signals of varying degrees of intensity or varying behavioural patterns dependent, at least to some extent, on the level of threat and/or degree of likelihood of a collision occurring; and for the secondary warning device to be a strobe light controlled by the processor or a controller to flash vigorously when a high level of threat or likelihood of a collision occurring is determined by the electronic processor.

The invention further provides a method of warning a road user of the possibility of a collision with an object approaching it from a direction not ordinarily in the field of vision of the road user occurring, the method comprising sensing the presence, location and velocity relative to the road user of objects within a field and range of detection of a sensor orientated in the direction, processing data generated by the sensor using computational or artificial intelligence optionally in combination with one or more appropriate algorithms to determine a level of threat posed by an approaching vehicle or a degree of likelihood of a collision occurring between the vehicle and the object and to provide an output based, at least to some extent, on the level of threat or likelihood, and activating a controller for a warning device configured to communicate a warning signal to the operator on the basis of such output.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be described, by way of example only with reference to the accompanying representations in which:

Figure 1 is a block diagram of one embodiment of a system according to the invention for warning a road user of the possibility of a collision with an approaching object; Figure 2 is a side elevation of a bicycle fitted with an early warning system as described with reference to Figure 1 ; and Figure 3 is a plan view of a road showing a cyclist utilising a collision early warning system in accordance with the invention.

DETAILED DESCRIPTION WITH REFERENCE TO THE DRAWINGS

A warning system (1) as provided by this invention is represented by the block diagram shown in Figure 1 and is shown installed on a bicycle (2) in Figure 2. The system includes a sensor (3), which in the current embodiment is a micro-radar. The radar (3) has a predetermined field and range of detection represented in Figures 2 and 3 by the triangular area indicated by numeral (4). While it is foreseeable that a large variety of sensors may be suitable for use with the system and method of the invention, it is presently proposed to use a low power radar sensor, preferably an FMCW radar. The radar proposed to be used consumes approximately 5 mW of power and has an effective sensing range of approximately 100 meters.

Such radar sensors typically operate in the X-band of frequencies which ranges from approximately 8.0 to 12.0 GHz. The radar utilises two antennas, one for transmitting and one for receiving. It is however foreseeable that a larger number of antennas may be used. In the application of the present invention it is essential that the position of each object sensed in the sensing field (4) is capable of being accurately determined. To do this a signal is transmitted from the antenna and reflections from objects in the sensing field are then received on the receiving antenna and analysed.

The Doppler shift of the received signal is also determined and used to determine the object's instantaneous speed according to the Doppler principle, weather the object is moving towards or away from the sensor, and also the rate at which the distance from the sensor to the object that is being observed is changing with respect to time (this is often referred to as the range-rate of the object). The measurements are done continuously at high frequencies, typically multiple times a second. This arrangement enables the movement of objects sensed within the sensing field (4), including their velocities relative to the sensor (3) and, most importantly, their direction of travel to be determined and the behaviour of the objects to be tracked as they move through the sensing field (4). This behaviour can then be compared to information contained in a database in order to calculate potential levels of threat to the road user and identify potentially dangerous situations.

The data generated by the radar (3) is relayed to an electronic processor (5) in the form of a computer or microprocessor which processes and analyses the data and, in turn, provides an output signal to a controller (7) based at least to some extent on the data sensed by the radar sensor (3). The controller controls a warning device (8), in the current embodiment an array of six light emitting diodes (LEDs) arranged in a row and installed so as to be visible to the cyclist during cycling. It should immediately be apparent that the processor (5) may also control the warning device (8) directly, without it being necessary to go via the controller (7).

The radar (3) is installed in a convenient location on the bicycle (2) so that its field and range of detection (4) covers at least a portion of the road area towards the rear (13) of the bicycle. A convenient place to install the radar (3) is underneath the seat (10) of the bicycle. The warning device (8) is in turn installed on the handle bars (9) of the bicycle (2) so as to be visible to the cyclist during use.

The output from the processor (5) to the controller (7) is generated on the basis of computational or artificial intelligence optionally in combination with one or more appropriate algorithms stored in computer readable format on a database associated with the processor. By using the data sensed by the radar sensor (3) and the algorithms the processor calculates, based at least on the position and velocity of objects sensed in the sensing field, firstly whether such objects are approaching the bicycle (2) and, secondly, what the level of threat is that the approaching vehicle (or other object) poses to the cyclist. This level of threat may include a degree of likelihood, based on their travelling speed and direction of travel, of any of the objects colliding with the bicycle. To assist in doing the calculation the database contains a series of thresholds which, once exceeded by an object travelling towards the cyclist, indicates that the object has entered a state from where there is a high likelihood that it will not have sufficient time to take corrective action to avoid a collision with the cyclist. One way of determining whether a sensed object is moving directly towards the bicycle is to compare the object's instantaneous (Doppler) speed with its range rate. If these are the same it implies that the object is moving directly towards the bicycle. The speed at which the object is approaching as well as its distance from the bicycle will then give an indication of the level of threat the object poses to the cyclist as well as whether or not the object will be able to brake sufficiently early to avoid a collision or weather a collision is imminent, thus requiring immediate evasive action from the cyclist.

The processor (5) then generates an output signal to the controller (7) (or to the warning device directly, as the case may be) which is proportional to the level of threat and/or the degree of likelihood of a collision occurring. The controller (7), in turn, illuminates one or more of the LEDs in response to the output signal. A high level of threat, for example, causes the controller to illuminate the majority, or all, of the LEDs, whereas a small number of illuminated LEDs correspond to a low level of threat. The LEDs in the current embodiment are of different colours. The first three are green and represent a low to average level of threat, with three green LEDs illuminated simultaneously representing a higher level of threat than one or two. The following two LEDs are amber and represent an average to high level of threat. The final LED is red and represents a critical level of threat or imminent collision risk, thus requiring the cyclist to take immediate evasive action such as, for example, driving off the road surface.

It should be appreciated that various levels of threat indicated on the warning device (8) may indicate to the cyclist the degree of evasive action he or she may wish to take. A low level of threat could, for example, simply indicate to the cyclist that he or she should stay close to the edge of the road or, even more importantly, not move towards the centre of the road, while a high level of threat may require much more drastic action.

The algorithms and predefined thresholds are also adapted to discard objects that obviously do not present a threat to the cyclist. These could, for example, include other cyclists, stationary objects and objects moving away from the sensor. To aid in this determination the radar (3) or processor (5) may also be able to ascertain the relative size of an object headed towards it. The system may therefore be able to determine whether an object is a passenger vehicle, other motor vehicle, bicycle, public transport vehicle such as a bus or mini bus, or even a pedestrian. The size of the motor vehicle detected could also indicate to the road user the expected amount of air turbulence he or she should prepare for.

In addition to the features already described, the system (1) also includes a secondary warning device (11) in the form of a light which is also controlled by the controller (7) or processor (5), directly, and which is conveniently installed adjacent the radar sensor (3) so as to be clearly visible from the rear of the bicycle by approaching objects. The controller (7) is configured to control the secondary warning device (11) to emit visual warning signals of varying degrees of intensity or varying behavioural patterns dependent, at least to some extent, on the level of threat and degree of likelihood of a collision occurring as determined by the processor (5). Objects approaching the cyclist causes the processor (5) to send control signals to the secondary warning device (1 1 ), causing it to flash. The intensity and/or frequency of the flash may be directly proportional to the level of threat and/or degree of the likelihood of a collision occurring. Unlike currently available rear bicycle lights this secondary warning light (1 1 ) conserves energy in that it only activates in potentially dangerous situations and when vehicles are approaching the bicycle from behind. It is therefore intelligent and much more effective in informing motorists of the bicycle's presence. From the above it will be clear that the system according to this invention is able to determine the level of threat and the likelihood of a collision occurring between the road user utilising the system and an object such as a motor vehicle approaching it from a direction not generally in the field of the view of the road user, such as the rear, and warning the road user in time to take evasive action, thus avoiding collisions and potentially saving the road user's life.

The system may also be able to identify and track the movement of a number of objects within the sensing field simultaneously. In such a scenario it may also be able to determine the location, speed, direction of travel as well as potentially other parameters of each of the identified objects and determine a level of threat and likelihood of any of these objects being involved in a collision with the road user. As shown in more detail in Figure 3, a cyclist (14) using a bicycle (2) utilising a system in accordance with the invention, and who is cycling along the edge ( 5) of a road (16), will receive warning if a vehicle (17), travelling within the system's sensing field (4) is approaching it from behind. Due to its current velocity and distance from the sensor, it may pose a level of threat to the cyclist or may even be likely to collide with him or her. The warning device in the cyclist's field of vision will indicate the presence, as well as the level of threat posed by the object to the cyclist. This will allow the cyclist to take immediate evasive action, if required, by, for example, cycling off the road and onto the pedestrian walkway (18) running alongside the road. The processor of the system will also be able to determine that a vehicle (19) travelling in the opposite direction (20) to the bicycle, when it enters the sensing field (4), is travelling away from the bicycle and will not pose a potential collision threat.

Unlike prior technologies the collision early warning system of the invention is equally effective under good and bad light conditions, as the radar sensor is not dependent on light for effective operation. The system enables the road user to make intelligent, pro-active decisions to enable him or her to avoid collisions with motor vehicles which may otherwise have been unavoidable. These decisions can be made as a result of the fact the real-time dynamic attributes of the sensed objects approaching the road user are available and can be utilized in real time before the accident occurs.

The secondary warning device will also provide additional warning to approaching motor vehicles, particularly in high collision risk scenarios and unlike previous technologies will indicate, at least to an extent, the degree of impending danger. In addition, the secondary warning device will not be a continuous warning of the presence of the road user and will as such be less likely to be ignored by approaching motor vehicles. The secondary warning device may only be activated in high collision likelihood scenarios and will as such be an indication to the motorist that immediate evasive action is required.

It will be understood that numerous variations may be made to the system described above without departing from the scope of the invention. In particular, it is envisaged that alternative sensors such as infra-red, Laser, optic sensors, video sensors, ultrasonic sensors or other sounds driven sensors may be used with similar effect. In additional, the warning device may take on a variety of different embodiments such as other illuminated devices or even mechanical dials.

It is also envisaged that the system may be used by road users other than cyclists such as, for example, pedestrians, recreational road users and construction workers. In such embodiments the sensor may be provided with attachment formations to enable it to be carried or worn on the back by the person. This alternative embodiment may also utilise alternative warning devices such as mechanical actuators, buzzers or even devices capable of delivering a mild electrical shock or other tactile warning to the user to indicate levels of threat and likelihoods of collisions. These warning devices may be secured to appropriate places of the user's body where it will be sure to get the user's attention. In some cases the warning device may also produce and audible warning signal. The system may or may not still make use of the secondary warning device for warning incoming objects of the likelihood of a collision occurring.

The system of the invention may also be adapted to integrate with existing electronic appliances frequently worn by road users, in particular recreational users. These appliances may include cellular phones, portable music players such as MP3 players, l-pods®, portable global positioning systems especially adapted for training purposes, exercise equipment such as heart rate monitors, wrist watches, trip counters, bicycle computers and bicycle speedometers to name but a few. In these embodiments the warning devices may be incorporated in the appliances and the output of the controller or processor directly may be conveyed to the appliances and appropriate warning indicators activated on standard displays, sound or movement actuators or the like. The warning device may likewise by placed in any convenient location such as, for example, in a cyclist's helmet or incorporated in sunglasses or other protective eyewear worn by the cyclist. It is also foreseen that the warning devices may be incorporated in units configured to be positioned at the extremities of the bicycle's handle bars, in which case they may provide warning signals to the cyclist and other motorists alike. The system may also incorporate an accelerometer in communication with the processor and configured to detect when a cyclist has been involved in an accident or collision. The system may then transmit a distress signal by means of an appropriate transmission mechanism. The distress signal may, for example, include a vehicle identifier or GPS coordinates of where the accident occurred. The accelerometer may also cause the warning lights of the system to go into a continuous flashing state once an accident has been detected. This will make the bicycle more visible and increase the chances of the potentially injured cyclist being located and assisted quickly, particularly in low light conditions.

It should also be apparent that the system according to the invention not only warns its user of impending threats and possible collisions, but also of any objects approaching it from outside his or her normal field of vision. These features also make the system useful in situations where, for example, a cyclist wishes to change lanes or cross busy intersections.

Claims

CLAIMS:

A warning system (1) for a road user comprising

a sensor (3) adapted to be mounted so that a field (4) and range of detection thereof is directed in at least one direction not ordinarily in the field of view of the road user, the sensor (3) being configured to develop data relating to the presence and movement of objects sensed within the field (4) and range of detection;

a warning device (8) configured to provide a warning signal to the road user; and

an electronic processor (5) configured to receive and analyse the data developed by the sensor (3) and to transmit control signals to the warning device (8) based, at least to some extent, on the analysed data,

the system being characterised in that the electronic processor (5) is further configured to identify at least one object approaching the road user from the direction, to calculate a level of threat posed by the approaching object, and to provide a control signal to the warning device (8) causing the warning device (8) to produce a warning signal to the road user proportional in intensity to the level of threat.

A warning system (1) as claimed in claim 1 in which the sensor (3) is a radar sensor configured to include information relating to the velocity and direction of movement of the sensed objects in the data.

A warning system (1) as claimed in claim 1 or claim 2 which includes attachment formations for securing the device on the person of the road user or on a vehicle operated by the road user.

A warning system (1) as claimed in claim 3 in which the vehicle is a bicycle (2). A warning system (1) as claimed in any one of the preceding claims in which the warning device (8) is a visual display configured to be mounted in a dominant field of vision of the road user and includes a variable display capable of displaying visual warnings of varying intensity in response to the control signal received from the electronic processor (5).

A warning system (1) as claimed in claim 5 in which the visual display includes an array of light emitting diodes (LEDs) configured to light up sequentially in accordance with the level of threat calculated by the electronic processor (5).

A warning system (1) as claimed in any one of claims 1 to 4 in which the warning device (8) is a mechanical or electrical actuator including an attachment formation for removably attaching it to the person of the road user, the actuator being configured to deliver tactile warning signals of varying intensity to the road user in response to the control signal received from the electronic processor (5).

A warning system (1) as claimed in any one of the preceding claims which includes a secondary, visual warning device (11) for displaying warning signals to the objects approaching the road user from the direction, the secondary warning device (11) being controlled by the electronic processor (5) and being configured to emit warning signals of varying degrees of intensity or varying behavioural patterns dependent, at least to some extent, on the level of threat calculated by the electronic processor (5).

A warning system (1) as claimed in claim 8 in which the secondary

warning device (11) is a strobe light configured to flash at varying rates proportional to the level of threat.

10. A warning system (1) as claimed in any one of the preceding claims in which the electronic processor (5) is programmed to calculate the level of threat on the basis of computational or artificial intelligence in combination with one or more appropriate algorithms.

11. A warning system (1) as claimed in any one of the preceding claims which includes an accelerometer in communication with the electronic processor and configured to enable the processor (5) to establish when a collision between the road user and an object has occurred.

12. A warning system (1) as claimed in claim 11 which includes a transmitter configured to transmit a distress signal when the processor (5) establishes that a collision has occurred.

A warning system (1) as claimed in claim 12 which includes a global positioning system configured to provide the geographical coordinates of the road user for transmission over the transmitter.

A method of warning a road user of an object approaching it from a direction not ordinarily in the field of vision of the road user comprising: generating, by means of a sensor (3) orientated in the direction, data relating to the presence, location and velocity relative to the road user of an object within a field (4) and range of detection of the sensor; analysing, by means of an electronic processor (5), the data generated by the sensor (3) to determine a degree of likelihood of a collision occurring between the road user and the object; and generating, using a warning device (8), a warning signal to the road user proportional in intensity to the degree of likelihood of a collision occurring as determined by the electronic processor (5). A method as claimed in claim 14 in which analysing the data further comprises using computational or artificial intelligence in combination with one or more appropriate algorithms.