Patent Grant
7061372
1. Field of the Invention
The present invention is related to collision avoidance systems, and more particularly to a stand alone sensor system with built in intelligence.
2. Background Information
The roadways are becoming more and more congested with vehicular traffic. As traffic congestion has increased, the number of accidents has also increased. Some of these accidents can be traced to driver inattentiveness or to the failure of the driver to see another vehicle. Many accidents on the road are caused when drivers are changing lanes. The driver is unable to clearly see if another vehicle is either directly in or entering the lane to the right or left side of their vehicle. This is particularly true for large vehicles such as busses, vans, trucks, tractor trailer rigs, motor homes and vehicles towing trailers.
Accidents are also caused when backing a vehicle. The ability to see behind and around a vehicle while backing up is limited and even more limited the larger and less transparent the vehicle being backed up is. Not only is this true for professional drivers such as truck drivers and bus drivers but this is true for nonprofessional individuals driving moving vans, towing recreational items such as boat trailers, ski mobile trailers, storage trailers or driving recreational vehicles such as campers and motor homes. Potential hazards when backing a vehicle include stationary and moving objects, posts, vehicles, pedestrians (in particular children), people on skateboards, roller blades and bicycles that are in or move into the path of the moving vehicle.
Systems for warning drivers of objects external to their vehicle have been around for a long time. Mirrors, and sometimes combinations of mirrors, are being used to reveal locations hidden to the driver's view (i.e. “blind spots”). Mirrors, however, have a deficiency in that the driver can only look in one spot at any one time. If they look behind the vehicle, see that the way is clear, start looking elsewhere and then a vehicle pulls behind them, they won't see it and may back into the vehicle. In addition, mirrors don't work well when changing lanes. If a driver looks at the lane adjacent to the vehicle and sees that the way is clear then starts looking elsewhere and a vehicle pulls along side them, they won't see it and may clip the vehicle while changing lanes. With tractor-trailer rigs, as soon as the rig begins to turn, the mirror that looked down along the side of the vehicle is directed into the side of the trailer and the driver is blinded to activity on that side of his truck. What is needed is a collision avoidance system to alert drivers of vehicles or objects within their path for a variety of applications.
There are also problems with vehicle detection in stationary situations such as work zones. Work zone areas may be along or on roadways or highways. The lanes often narrow in the work zone area and construction workers are working in close proximity to the traffic. Work zones call for the reduction of speed limits. Currently stationary warning signs and individuals signaling the traffic to stop or slow down are not able to adjust for changing conditions within the work zone. For example heavy-duty vehicles, such as dump trucks, entering the roadway at the work zone, often traveling at slow speeds, pose additional hazards. The narrowing of the roadway, the high speed of drivers approaching the roadway, the proximity of construction workers, and the movement of construction vehicles in the vicinity of the work zone present hazardous conditions that often result in accidents and fatalities. What is needed is a warning system that dynamically adjusts the situation.
The current collision avoidance systems are either designed as multiple sensor systems having central intelligence through an on board computer or as single sensors with no built-in intelligence. These systems are inflexible as they are designed to provide detection for a predetermined application and are not situation specific for each user. For example, a bus driver may find that the area under the front wheels is the most dangerous and would like an object detection system for that specific location. A snow plow driver has a need for detection of vehicles approaching too fast from behind. A truck driver requires rear object detection for backing into delivery bays. The current detection systems are not flexible enough to meet all of these needs cost effectively. The current systems are also inflexible for independent truck drivers who own a tractor and transport a variety of customer's trailers. The current detection systems are not interoperable. An individual truck driver having a tractor with one on board computer system is not necessarily able to interface with the collision avoidance system available on each customer's trailer. In addition, many of the trailers are not equipped with any detection devices and the truck driver is left with no collision avoidance capability. What is needed is a flexible object detection system capable of meeting a diversity of drivers needs that provides a common interface for a variety of detection systems.
In addition, most of the current collision avoidance systems are expensive and are not considered cost effective for many trucking companies and independent truckers and are considered cost prohibitive for non-professional drivers. The systems are not flexible enough to allow the user to add or remove sensors as required for their particular application. Additional sensors for many systems cause the whole system to be redesigned at a high cost to the user.
The above mentioned problems with collision avoidance and detection systems and other problems are addressed by the present invention and will be understood by reading and studying the following specification.
According to one aspect of the invention, a stand alone sensor module, that detects objects about a vehicle or a stationary location, is provided. The sensor module includes a processor connected to a sensor and a signal interface and receives signals from the sensor and the signal interface. The processor generates a hazard status signal as a function of the signals received from the sensor and the signal interface and drives the vehicle status signal to the signal interface.
According to another aspect of the invention, a stand alone sensor module is provided. The sensor module includes a processor connected to a sensor and a signal interface and receives signals from the sensor and the signal interface. The processor generates a vehicle status signal as a function of the signals received from the sensor and the signal interface and drives the vehicle status signal to the signal interface.
Further, according to another aspect of the invention a collision avoidance system is provided. The collision avoidance system includes a first stand alone sensor module connected to a second stand alone sensor module and a display module coupled to both the first and second sensor modules. The first stand alone sensor module includes a first sensor coupled to a first processor. The first processor is connected to a first signal interface. The first processor receives signals from the first sensor and the first signal interface and drives a first vehicle status signal to the first signal interface as a function of the signals received from the first sensor and first signal interface. The second stand alone sensor module includes a second sensor coupled to a second processor. The second processor is connected to a second signal interface. The second processor receives signals from the second sensor and the second signal interface and drives a second vehicle status signal to the second signal interface as a function of the signals received from the second sensor and second signal interface. The display module receives the first and second vehicle status signals and displays vehicle status information representative of the first and second vehicle status signals.
A method of detecting an object with a stand alone sensor module is provided. The method includes receiving vehicle condition signals, transmitting a detection signal and receiving a return of the transmitted detection signal. The method further includes determining whether a hazard exists based on the return of the transmitted detection signal and the vehicle condition signals and transmitting a vehicle status signal to an information device.
In the following drawings, where the same number reflects similar function in each of the drawings,
In the following detailed description of the preferred embodiments, reference is made to the accompanying drawings that form a part hereof, and in that is shown by way of illustration specific embodiments in that the invention may be practiced. It is to be understood that other embodiments may be utilized and structural changes may be made without departing from the scope of the present invention. The following detailed description is, therefore, not to be taken in a limiting sense.
Some portions of the detailed description that follows are presented in terms of algorithms and symbolic representations of operations on data bits within a computer memory. These algorithmic descriptions and representations are the means used by those skilled in the data processing arts to most effectively convey the substance of their work to others skilled in the art. An algorithm is here, and generally, conceived to be a self-consistent sequence of steps leading to a desired result. The steps are those requiring physical manipulations of physical quantities. Usually, though not necessarily, these quantities take the form of electrical or magnetic signals capable of being stored, transferred, combined, compared, and otherwise manipulated. It has proven convenient at times, principally for reasons of common usage, to refer to these signals as bits, values, elements, symbols, characters, terms, numbers, or the like. It should be borne in mind, however, that all of these and similar terms are to be associated with the appropriate physical quantities and are merely convenient labels applied to these quantities. Unless specifically stated otherwise, as apparent from the following discussions, it is appreciated that throughout the present invention, discussions utilizing terms such as “processing” or “computing” or “calculating” or “determining” or “displaying” or the like, refer to the action and processes of a computer system or similar electronic computing device, that manipulates and transforms data represented as physical (electronic) quantities within the computer system's registers and memories into other data similarly represented as physical quantities within the computer system memories or registers or other such information storage, transmission or display devices.
In one embodiment, the a stand alone sensor module 100 is employed on a vehicle. Input signals that contain vehicle conditions are received from vehicle systems such as the vehicle's engine electronics or electronic control module, transmission, lighting systems, safety systems, trailer electronics, a centralized computer system and any number of vehicle monitoring systems as well as other sensor systems. The input signals are analog and/or digital signals. The vehicle conditions include information such as whether or not the vehicle is in park, reverse or drive, whether or not the brakes or parking brakes are engaged, the speed of the vehicle, whether or not a directional is engaged, that another vehicle is approaching and at what speed and the like. As an example, vehicle speed information may be received by a stand alone sensor module 100 from any number of sources to include the electronic control module, sensors built into a transmission, a radar sensor used to detect vehicle speed, and inputs from a sensor built into a trailer. In addition, vehicle direction can be determined by a stand alone sensor module 100 when receiving vehicle condition inputs from a transmission reverse switch, a manual activation of a flasher system by an operator or driver, or any number of devices indicating or sensing vehicle movement.
In one embodiment, the signal interface 14 is a data bus that is compatible with communication systems to include centralized communication systems and satellite positioning systems used on vehicles in the trucking industry, bus lines or the like. In one embodiment, the signal interface is an SAE J1708 data bus, currently a standard data bus for large vehicles. In another embodiment, the signal interface is an SAE J1939 data bus, another standard data bus for large vehicles. In one embodiment, a stand alone sensor module 100 is used with any variety of vehicles having any number of communication interfaces and/or information devices. In another embodiment, stand alone sensor module 100 provides output to one or more information devices mounted in or on vehicle. In an alternate embodiment, stand alone sensor module 100 provides output to one or more information devices outside of the vehicle. In a further embodiment, stand alone sensor module 100 provides output to one or more information devices mounted in or on a vehicle and outside of the vehicle.
In another embodiment, the a stand alone sensor module 100 is employed in a stationary environment such as a work zone. Input signals that contain hazard conditions are received from other sensors or information devices within or outside of the work zone environment. The input signals are analog and/or digital signals. The hazard conditions include information such as a vehicle is approaching the work zone and at what speed, a vehicle is approaching the road in preparation for entering the roadway, people are working close to the traffic in a work zone and the like
Processor 10 communicates with sensor 12, receiving inputs, that include signal data from sensor 12, and sending commands to sensor 12. In one embodiment, processor 10 receives input signals from additional sensors. The additional sensors include a stand alone sensor modules, slave sensors and other detection sensors. In one embodiment, a slave sensor includes a transmitter and receiver and transmits and receives signals to detect objects within its signal path or field-of-view, FOV. In one embodiment, the transmitter and receiver are contained in a single housing. In another embodiment the transmitter and receiver are contained in separate housings. In an alternate embodiment, a slave sensor includes a transmitter, receiver, an antenna and electronics for transmitting, receiving signals and further transmission of received signals electrically or wirelessly. It is understood that a slave sensor is not limited to a transmitter and receiver and may include additional electronics for various detection technologies i.e. laser, laser radar (ladar), ultrasonic, radar, video, infra red, photoelectric and the like.
Sensor 12 transmits and receives signals in order to detect any objects within the proximity of a host vehicle or within or outside a work zone area. The sensor has a field-of-view, FOV, as shown in
Processor 10 receives signal data and vehicle or hazard condition information and generates status information. In one embodiment, processor 10 generates vehicle status information. Vehicle status information includes the presence of a hazard such as an object is within the path of the vehicle, an object has moved into the path of the vehicle while backing up, an object is detected under the wheels, the vehicle does not have enough clearance to pass under a sign or an overpass, another vehicle is approaching too quickly and the like. Vehicle status information also includes the absence of a hazard such as no hazard has been detected, all sensors are functioning, some sensors are functioning and the like. In one embodiment, processor 10 generates hazard status information. Hazard status information includes for example a vehicle is approaching a work zone too quickly, a vehicle is approaching the work zone when another vehicle is entering the roadway, people are working close to the traffic in a work zone, no hazard has been detected, all sensors are functioning, some sensors are functioning and the like.
Processor 10 determines whether or not detected objects present a hazard and transmits the results to an information device. Processor 10 dynamically adjusts based on information received. For example, a stand alone sensor module can be preprogrammed to detect objects as a hazard when a directional has been engaged and an object is within 10 feet of the side of the vehicle or when the vehicle is backing up the threshold for side object detection may be programmed at 4 feet or some other value. It is to be understood that distance from the vehicle or sensor determined as a hazard may vary from one application to another application. Processor 10 is capable of receiving information from a number of sensors and determining if a hazard exists, the sensors include stand alone sensor modules, slaves or other detection sensors. The field-of-view for a stand alone sensor module is expandable by connecting slave sensors to the stand alone sensor module. The slave sensors provide information to processor 10, processor 10 uses the information to determine whether or not a hazard exists based on the current vehicle or hazard conditions. The stand alone sensor module is a scalable system by adding additional stand alone sensor modules, slave sensors or other detection sensors. In one embodiment, stand alone sensor module 100 allows for the addition of multiple stand alone sensor modules to provide partial or full periphery monitoring of areas around a vehicle with the ability to provide the vehicle driver with information pertinent to all hazards in any location around the vehicle. In one embodiment, stand alone sensor module 100 allows for the addition of multiple stand alone sensor modules to provide partial or full periphery monitoring of a location in and around a work zone or other areas needing monitoring with the ability to provide pertinent hazard information to individuals within the work zone or approaching the work zone. Status information received
In one embodiment, a built-in-test capability is provided. Stand alone sensor module 100 determines if it is functional or not, if sensors coupled to stand alone sensor module 100 are functional or not and if signal data is being received from sensors connected to stand alone sensor module 100. This information is then communicated to any number of information devices in order to communicate a failure if it is not performing properly, or to communicate a success if it is performing properly. In one embodiment, a self-test mode is activated. A display or control module is provided which provides an indicator for each sensor mounted around the vehicle and on entering self-test mode sensor indicators begin to flash. So now what the driver can do is get out and literally walk around his vehicle, get back in the cab. Every one of those sensors should have detected him and every time they detect him, the sensor indicator associated with the sensor goes off (i.e., quits flashing). If the driver gets back to the cab and there's an indicator still flashing, he knows that something didn't work and he's got a problem.
In one embodiment, stand alone sensor module 100 includes sensor 12 having a single sensor such as an ultrasonic sensor, a radar sensor, a laser radar or ladar sensor, an infrared sensor or the like. In another embodiment, stand alone sensor module 100 includes sensor 12 having two or more sensors employing similar or different technologies, radar, ultrasonic, ladar, infrared and the like. For example in one embodiment, stand alone sensor module 100 includes sensor 12 having a radar sensor and an ultrasonic sensor. However, the present invention is not limited to ultrasonic and radar detection technologies and may include any variety of detection technologies such as photoelectric, video, laser, ladar and/or infrared.
In an alternate embodiment, stand alone sensor modules 400 and 402 are coupled to an information device such as a centralized computer system that provides a broad range of vehicle data information to a driver such as engine monitoring, systems checks, security information, trip data, vehicle location such as global positioning and the like. In another embodiment, stand alone sensor modules 400 and 402 are coupled to an information device such as a black box data recorder for accident reconstruction or safety statistic data. In a further embodiment, stand alone sensor modules 400 and 402 are coupled to a satellite system for centralized tracking by trucking companies, bus and train lines and the like. In another embodiment, stand alone sensor modules 400 and 402 are coupled to a display module and a centralized computer system or a black box data recorder or a satellite system or any combination of information devices to include all of these information devices.
Stand alone sensor modules 100, 200, 300, 400 and 500 discussed with respect to
In an alternate embodiment as illustrated by
The object detection system described in
It is understood that an information device includes any device or devices such as display modules, centralized computer systems, data recorders or “black box”, satellite tracking systems and/or a warning systems.
It is also understood that processor 10 of a stand alone sensor module includes any microprocessor or central processing unit containing the basic arithmetic, logic and control element for processing data. In one embodiment, processor 10 is a programmable microcontroller. In another embodiment, the programmable microcontroller is field upgradable for complete peripheral object detection about a vehicle or area to be monitored. In a further embodiment, the programmable microcontroller is compatible for operation with a centralized computer system.
In one embodiment, determining when a hazard exists includes detecting an object in a predetermined range. In another embodiment, determining when a hazard exists includes determining the distance to the detected object and providing a signal to the information device based on the distance to the object.
In one embodiment, performing a built-in-test includes determining whether sensors connected to the stand alone sensor are functioning. In another embodiment, performing a built-in-test includes determining whether all systems connected to the stand alone sensor module are functioning.
In one embodiment, a stand alone sensor module is portable and used for object detection at any number of locations about a vehicle to include the rear of a vehicle while backing or moving forward, the wheel area, the sides of a vehicle, the top of a vehicle (clearance), in front of a vehicle and the like. In alternate embodiments, the stand alone sensor module is portable and includes a display module. In an alternate embodiment, the stand alone sensor module with a display include slave sensors coupled to the stand alone sensor module for additional object detection.
In one embodiment, a stand alone sensor module is scalable up to a collision avoidance system that provides full object detection about the periphery of a vehicle. In another embodiment, the collision avoidance system operates with a central computer fusing all data received from multiple sensors and providing vehicle status information.
In one embodiment, the stand alone sensor module receives signals from sensors and vehicle condition inputs and determines whether or not a hazard condition exists, such as the host vehicle has engaged the left directional and there is an object within the field of view of a side sensor that is within the path that the host vehicle is moving. In another embodiment, the processor receives signals containing range data and determines that not only is their an object within the field-of-view but it is within a first range i.e. 25 feet, a second range i.e. 15 feet, a third range and a fourth range and transmits this to an information device in order to warn the driver.
In an alternate embodiment, the stand alone sensor module determines that a hazard exists and the module initiates cautionary measures such as warning signs or signals, applying the vehicle's brakes, setting off an alarm system, not allowing the vehicle to move out of park and the like.
In one embodiment, the stand alone sensor module determines that the host vehicle is slowing down and activates rear brake lights on the vehicle or a trailer. In one embodiment, the stand alone sensor module includes lights that can be mounted on the vehicle or trailer to indicate slowing down, braking or a hazard exists.
In another embodiment, the processor receives signals containing range and speed data of an object to include another vehicle in relation to the host vehicle. In the situation where a snow plow is clearing snow and a vehicle is approaching the snow plow too quickly and the sensor receives data signals transmits them to the processor that determines that the approaching vehicle is proceeding too fast and the processor engages a hazard light to warn the approaching vehicle. The hazard light includes a sign, a high power light, a high power light system and/or some other indication to the approaching vehicle. In an alternate embodiment, a stand alone sensor module with or without slave sensors is employed in a work zone to warn approaching vehicles that they are entering a work zone, to slow down or to stop. The system employs a warning system to include a hazard light, a warning sign, mechanical or electrical, and/or some other indication to warn an approaching vehicle.
An object detection system has been described. The object detection system includes a stand alone sensor module that detects object about a vehicle or a stationary location. The stand alone sensor module includes a processor connected to a sensor and a signal interface. The processor receives signals from the sensor and the signal interface and drives a hazard status signal as a function of the signals received from the sensor and the signal interface.
In another embodiment, a stand alone sensor module comprising a sensor connected to a processor has been described. The processor includes a signal interface and receives signals from the sensor and the signal interface. The processor generates a vehicle status signal as a function of the signals received from the sensor and the signal interface and drives the vehicle status signal to the signal interface.
Further, according to an alternate embodiment, a collision avoidance system has been described. The collision avoidance system includes a first stand alone sensor module connected to a second stand alone sensor module and a display module coupled to both the first and second sensor modules. The first stand alone sensor module includes a first sensor coupled to a first processor. The first processor is connected to a first signal interface. The first processor receives signals from the first sensor and the first signal interface and drives a first vehicle status signal to the first signal interface as a function of the signals received from the first sensor and first signal interface. The second stand alone sensor module includes a second sensor coupled to a second processor. The second processor is connected to a second signal interface. The second processor receives signals from the second sensor and the second signal interface and drives a second vehicle status signal to the second signal interface as a function of the signals received from the second sensor and second signal interface. The display module receives the first and second vehicle status signals and displays vehicle status information representative of the first and second vehicle status signals. Although specific embodiments have been illustrated and described herein, it will be appreciated by those of ordinary skill in the art that any arrangement that is calculated to achieve the same purpose may be substituted for the specific embodiment shown. This application is intended to cover any adaptations or variations of the present invention. Therefore, it is intended that this invention be limited only by the claims and the equivalents thereof.
This application is a continuation of U.S. patent application Ser. No. 09/505,418 filed Feb. 16, 2000, now U.S. Pat. No. 6,642,839, which application is incorporated herein by reference.
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