MXPA00003432A - Method and apparatus for in-path target determination for an automotive vehicule using a gyroscopic device - Google Patents

Abstract

The present invention concerns a method, an apparatus and an article of manufacture that satisfies the need for determining whether or not an obstacle vehicle is in the path of a host vehicle. Specifically, the present invention satisfies the above stated regardless of whether or not the host vehicle is moving in a straight path or along a curved path. Preferably, input data ("input") is collected from instruments mounted to a host vehicle. The input is used to calculate for the host vehicle the average turn rate, the radius of curvature of the path being traveled, the velocity, and a range from the host vehicle to an obstacle vehicle. Additionally, the input is used to determine the deviation of an obstacle vehicle. Additionally, the input is used to determine the deviation of an obstacle from a 0°reference azimuth extending through the center of a radar beamating from a radar unit mounted to the host vehicle. An obstacle azimuth angle ai, is calculated and used to determine whether or not the obstacle is in the path of the host vehicle. After a determination is made as to whether or not the obstacle is in the path of the host vehicle, the results of that determination are sent to and displayed by sensors and displays which designate the results.

Description

METHOD AND DEVICE FOR DETERMINING A PATH TARGET FOR AN AUTOMOTIVE VEHICLE USING A GIROSCOPIC DEVICE Background of the Invention 1. Field of the Invention The present invention relates to vehicular radar systems, and more particularly to an apparatus, method and article of manufacture for a vehicle collision avoidance system that determines if an obstacle lies in the trajectory. of a host vehicle. 2. Description of Related Art There is a continuing need to increase the density of vehicles traveling on the roads of the world and simultaneously improve the safety of vehicle operations on roads, preventing vehicles on the roads from colliding with stationary objects and in motion (such as obstacles on the side of the road and other vehicles). Means to achieve these apparently contradictory goals involve monitoring the relative speed, the direction of travel, and the distance between a vehicle and any obstacle in its path, and using such information to provide alerts of potential danger to the driver of the vehicle. It has become increasingly common for automotive engineers to consider the use of radar systems as means to monitor-such environmental conditions. Radar systems are currently known on the edge of vehicles, which transmit and receive at three different frequencies on a time division basis, using two of the frequencies to determine the range, and the third being combined with one of the first two to determine the speed of approach and the possibility of collision. One such system is disclosed in U.S. Patent No. 3,952,303 to Watanabe et al., Which teaches a front end processing for analog radar system. Another example of an automotive radar system is described in U.S. Patent No. 5,402,129, entitled "Multi-Frequency Automotive Radar System", and assigned to the assignee of the present invention. In that system, a transmission signal and the reflected received signal are coupled to an RF mixer. The relevant output of the RF mixer is a signal having a frequency equal to the difference between the transmission and reception frequencies. The frequency of the reflected signal received can be shifted from the frequency of the transmission signal upon return, due to the "Doppler" effect. The Doppler effect occurs whenever a transmitted signal is reflected from an obstacle that has a relative movement to the transceiver. The resulting frequency shift is referred to as a "Doppler shift".

A further example of an automotive radar system, which mainly uses a digital approach, is described in U.S. Patent No. 5,302,596, entitled "Multi-Frequency, Multi-Target Vehicular Radar System Using Digital Signal Processing", and assigned to the assignee of the present invention. In that system, which includes a transmission section for generating two-channel transmission frequency, an antenna transmits both the transmission signal and receives a reflected reception signal. A diode mixer generates a difference signal having a frequency equal to the transmission frequency minus the received frequency. A signal switch in the front end electronic section multiplexes in time and shows the signals of channel one and channel two, following which the samples are coupled to a two-channel analog to digital converter. A digital electronic section receives the digital information and performs a fast Fourier transform on each digital data channel to determine the relative speed and range of an obstacle based on the frequency and phase difference of the two channels. The digital electronic section also receives information regarding the vehicle's operating status and / or controls to determine the degree of danger presented by an identified obstacle. In radar system to avoid vehicle collision, it is necessary to know whether or not there is an obstacle in the travel path of the host vehicle. This is typically done to determine if the obstacle is out of sight and, if so, the direction and magnitude of the angular error (angular deviation from vision). It is also desirable or necessary to know the distance or range of the obstacle. To provide continuous tracking, various systems have been proposed, including those that transmit a signal and then combine a multiplicity of replicas received variously from the signal. Examples of such systems are provided by U.S. Patent Nos. 4,060,809 to Baghdady, 4,975,710 to Baghdady, 5,084,709 to Baghdady and 5,128,969 to Baghdady. However, such systems have proven to have limitations that make them undesirable or impractical when used for radar systems to avoid vehicle collisions. Such systems are limited in their ability to provide data when the host vehicle with the radar system is on a curved path, as the mere knowledge of the angular error is insufficient to allow the radar system to avoid collisions to predict the trajectory of the host vehicle. with respect to the location of the obstacle. Accordingly, there is a need for a system that can predict the trajectory of the host vehicle with respect to obstacles identified by the system. SUMMARY OF THE INVENTION Broadly, the present invention concerns a method, apparatus, and article of manufacture used to determine whether or not an obstacle is within the path of a host vehicle. The invention provides a system that uses the digitized output of a device that measures the speed of. turning of the vehicle in order to obtain information about the turning radius. This information is used in conjunction with the information provided by a radar system to alert of an imminent collision and / or for cruise control functions. The present invention takes into account whether the host vehicle is moving in a straight path or along a curved path. In one embodiment, the present invention is implemented as a method for determining if an obstacle is in the travel path of the host vehicle. This determination is based on output data from one or more collection devices, such as a radar system, a turn speed indicator, and other instruments mounted on the host vehicle, such as a speedometer or tachometer. Initially, the outputs of the collection devices are used to determine the speed of the vehicle, the average speed of turn, the radius of curvature of the trajectory that is being displaced, the relative speed and range of any obstacles detected, and an angle of azimuth of obstacle, that is, the deviation of an obstacle of a reference azimuth of zero degrees (0") coinciding with the longitudinal axis of the host vehicle, which is preferably the vision of the radar systems. or obstacle is combined with the turn speed information to determine whether or not the obstacle is in the path of the host vehicle In another embodiment, the invention is an apparatus for determining whether the obstacle is in the trajectory of the host vehicle The apparatus receives input from a radar unit and a sensing device, such as a gyroscope, and includes a processor, storage digital, and a screen. In its preferred embodiment, a radar unit such as that described in U.S. Patent Nos. 5,302,956 or 5,402,129, both assigned to the assignee of the present invention, is used. Accordingly, these patents are incorporated herein by reference. In conjunction with the radar unit, a gyroscope is preferably used to collect additional input data. The gyroscope can be of any design, but it is preferred to use a low cost gyroscope. Alternatively, any device can be replaced by the gyroscope, such as a lateral accelerometer, or other device responsive to the turning speed, while the input returned to the system can be interpreted by the invention to determine the turning speed of the host vehicle. The radar unit and the gyroscope are coupled to circuits that allow calculations involving the input to be carried out. The calculations determine the turning speed for the host vehicle and whether or not an obstacle is in the path of the host vehicle. The results of that determination are sent to and displayed by sensors and screens that designate the results. In the preferred embodiment, the circuits include a filter for removing aberrant input data that is being received from the gyroscope, a storage unit, and the circuits necessary for radar implementation, as disclosed in the referred patents. In yet another embodiment, the invention is a manufacturing article comprising a data storage device that tangibly incorporates a program of machine-readable instructions executable by a digital data processing apparatus to carry out steps of the method for determining if the obstacle is in the path of the host vehicle. The invention provides its users with several distinctive advantages. An advantage of the invention is that the invention determines whether an obstacle is in the path of the reference vehicle, even if the host vehicle is traveling in a curved path. As such, the system can be used as a component of a cruise control system to control the speed of a vehicle, even when the host vehicle is on a curved path. The system can also be used to control the distance between the host vehicle and another vehicle in the curved path of the host vehicle. BRIEF DESCRIPTION OF THE DRAWINGS The nature, objectives, and advantages of the invention will become more apparent to those skilled in the art after consideration of the following detailed description in relation to the accompanying drawings, in which like reference numbers designate like parts , and where: Figure 1 is a plan view of a section of a road showing a desired beam width emanating from a host vehicle to track an obstacle to the exclusion of other obstacles, in accordance with an embodiment of the present invention; Fig. 2 is a plan view illustrating the manner in which the radar system determines deviation from view and range of an objective, in accordance with an embodiment of the present invention; Figure 3A is a plan view showing the manner in which the radar system determines out of sight deflection when traveling along a curved path, in accordance with an embodiment of the present invention; Figure 3B is a plan view illustrating the area seen by the obstacle determination unit in the path, according to an embodiment of the present invention; Figure 4 is a simplified block diagram of the apparatus used in accordance with an embodiment of the present invention; Figure 5 is a simplified block diagram of one embodiment of processing circuits, in accordance with an embodiment of the present invention; Figure 6 is a flow diagram of the steps of the method of an embodiment of the present invention; Figure 7 is a plan view of a curved section of a road showing an obstacle in the path of a host vehicle; and Figure 8 is an exemplary illustration of a data storage device that tangibly incorporates a program of machine-readable instructions executable by a digital data processing apparatus used in accordance with the present invention. Detailed Description of the Invention Widely, the current invention uses a path obstacle determination unit (IOD) to determine an obstacle in the path of a host vehicle or not. The invention can also be used in a cruise control device and in a variety of other applications. Figure 1 shows a host vehicle 111 equipped with an IOD unit 112 that travels over a portion of a road 110. The host vehicle 111 is "moved in a direction shown by an arrow 114 in a lane 116 of the road. 110. The IOD unit 112 of the vehicle 111 transmits a radar beam 118, which preferably extends from the front end of the host vehicle 111, where the IOD unit 112 is mounted. Alternatively, the IOD unit may be mounted on the side or top of the host vehicle 111. ~ The radar beam 118 is shown as encompassing an obstacle, such as the vehicle 120. The vehicle 120 is moving in the same direction as the host vehicle 111, as represented by an arrow 122, in lane 116. A third vehicle 124 is shown on a second lane 126 of the path 110, and traveling in an opposite direction of the host vehicle 111 and the vehicle 120, as represented by an arrow 128. In one embodiment, the IOD unit 112 includes a sensing device and a radar unit by means of which, among other things, the turning speed and radius of curvature for the host vehicle 111 can be determined. The IOD unit 112 also preferably includes other devices, such as a speedometer or the like, used to ensure the necessary information to perform an obstacle determination in the trajectory. The preferred manner in which the IOD unit 112 in the host vehicle 111 uses the radar beam 118 to track obstacles is shown in one embodiment in Figure 2. A radar beam 218 includes a zero-degree reference azimuth. 202 extending along the central view of the radar beam 218. The IOD unit 112 of the host vehicle 111 is preferably capable of tracking obstacles both in front of and on the sides of its travel path, such as the vehicle 220. The radar beam 218 provides a continuous indication of vehicle azimuth 220 with respect to reference azimuth 202, as well as indications regarding rank 208 and relative movement of vehicle 220 with respect to host vehicle 111. -IOD unit 112 determines the deflection angle 204, or condition out of view, shown as an angle? in figure 2, of the vehicle 220, based on signals reflected by the vehicle 220 and received by the IOD unit 112. In one embodiment, the radar beam 218 has an effective range of 350 feet in front of the host vehicle 111 and up to 60 feet in width in the maximum range. In other embodiments, the range and amplitude of the radar beam 218 may be increased or reduced, depending on the radar unit employed. The IOD unit calculates the azimuth 206 of the vehicle 220 in terms of the deflection angle 204. The sign of the deflection angle 204 determines on which side of the reference azimuth 202 lies the obstacle. The IOD unit also determines the range 208 of the vehicle 220 from the IOD unit 112 in a conventional manner, such as using transmission and double frequency reception, a technique that would be well known to those skilled in the art. Regardless of the embodiment, the IOD unit 112 can be used to alert, or help avoid collisions with the rear end, left side or right side of other vehicles that are on the road traveling in the same direction as the host vehicle and to illuminate obstacles on the side of the road, such as signaling poles, stones, pedestrians, or objects in adjacent travel lanes. If desired, the IOD unit 112 can also detect obstacles moving towards the host vehicle 111. In one embodiment, the sensor unit is used to collect data to determine the turning speed of the host vehicle 111, the turning radius 304 and other information. Referring to Figure 3, the turning speed of the host vehicle and the turning radius 304 are used in conjunction with the data of the radar beam 318 to determine whether or not an obstacle is in the path 324 of the host vehicle 111. As shown in FIG. shown in Figure 3, the host vehicle 111 is -displacement along a curved path in a direction shown by an arrow 314 on a rail 316 of the road 310. The IOD unit 112 of the host vehicle 111 transmits a radar beam 318 which extends from the front end of the host vehicle 111 where the IOD unit 112 is preferentially mounted. The radar beam 318 is shown as encompassing a vehicle 320. The vehicle 320 is moving in the same direction as the host vehicle 111, as represented by an arrow 322, located in lane 326. In the first instance, it would resemble the beam of radar 318 that the vehicle 320, as "seen" by the radar, is in the trajectory of the referred vehicle 111, because a deflection angle (not shown) (the angle between the reference azimuth 302 and the azimuth 306, as determined by the circuits 500 of the present invention in the preferred embodiment) is zero. However, by using the input of the sensing device of the IOD unit 112 to determine the average turning speed and turning radius 304 of the host vehicle, an obstacle azimuth angle OI can be calculated by the present invention. The angle I heard is used, as discussed below, to determine whether or not the vehicle 320 lies in the path of the host vehicle 111 when the host vehicle 111 is traveling along the curved path 324. If so, it may be required. an alert and / or an evasive action. Using the additional input to determine the average turning speed and turning radius 304, the radar detection zone used to determine obstacles in the path can be "shaped" to the course of a path, as shown in FIG. 3B. Operation Hardware Components and Interconnections A more detailed discussion of the apparatus of the invention follows. In an embodiment of the invention, a processor determines whether or not an obstacle is in the path of the host vehicle. As shown in Figure 4, the system of the invention 400 includes the IOD unit 112, which preferably comprises a radar unit 402 and a sensor device 404, the circuits 500 of the present invention, and a display and sensors of control 403. In one embodiment of the invention, the radar unit 402 of the IOD unit 112 may be as shown in U.S. Patent No. 5,402,129, incorporated by reference herein, and assigned to the assignee. of the present invention. The radar unit 402 transmits a radar beam which can be adjusted, and which is selected to track targets placed in front of the host vehicle. For example, the radar unit 402 used in the IOD unit 112 of the host vehicle 111, preferably transmits energy to the lane 316., shown in Figure 3A, in which the host vehicle 111 is traveling. At the same time, the radar beam is preferably wide enough to transmit to the adjacent lane 326 as the host vehicle 111 passes around curves on the road 310. However, the radar beam is not so wide as to include targets. potentials, such as the vehicle 124 shown in Figure 1, which are placed quite close, and adjacent, to the host vehicle 111. Because the trajectory of the vehicle 124 is such that the vehicle 124 will pass safely through the host vehicle 111 , the preferred embodiment of the present invention does not track the vehicle 124. In another embodiment, the radar unit 402 is like that shown in U.S. Patent No. 5,302,596, incorporated by reference herein, and assigned to the assignee of the current invention. Although the radar unit is different from the radar unit discussed above, the capabilities to track an obstacle are substantially similar. Moreover, any tracking device, such as an ultrasound range detection system, can be used in place of the radar units discussed, so long as the resulting tracking capabilities are similar to those of the referred radar units. In another embodiment, the sensor device 404 of the IOD unit 112 can be a gyroscope. A low cost gyroscope is preferred. However, as is well known by those skilled in the art, gyroscopes, especially low cost gyroscopes, characteristically have a polarized output. In other words, when host vehicle 111 is traveling along a substantially straight path, the gyro will still have a nominal output. This output is non-linear. Furthermore, inexpensive gyroscopes are susceptible to drift due to various effects, particularly changes in ambient temperature and the quality of the gyroscope. The output of the gyroscope (particularly low cost gyroscopes) is such that the drift can be equivalent to an angular velocity of a few degrees per second over a temperature change of 80 Y. For example, a gyroscope tested in a camera thermal over a temperature cycle of minus 20 Y to plus 50 Y you may experience a polarization change equivalent to around 2'C per second. As the polarization will present drift depending on the time lapse that the gyroscope has been "energized", the polarization should be filtered, as discussed below, by processing the data received from the gyroscope, preferably using a high pass filter. In one embodiment, the screen and sensors 403 are used to collect and display additional information, and to display the results of the target determination in the trajectory. The display and sensors 403 can also activate systems to avoid collisions, such as a warning bell, a system that takes control over the driver, or the like. The sensors may include a speedometer, a speedometer, an accelerometer, pitot tubes, or similar types of sensors to determine the speed of the host vehicle. The screen may comprise a video screen, an audio output, such as a tone, or a similar output that draws attention to the fact that an obstacle is in the path of the host vehicle. Figure 5 illustrates a filter 502 included in an embodiment of the circuits 500 of the present invention and used to filter 502 the input of the sensor device 404. In the preferred embodiment, the filter eliminates, among other things, the data target determination in the trajectory for any object moving towards the host vehicle 111, such as cars moving in the opposite direction of travel. However, in an alternative embodiment, objects that move in the opposite direction will be detected. In the preferred embodiment, the circuits 500 are a processor 506. In another embodiment, the circuits 500 include the processor 506, a storage unit 504, and commonly known elements 508 necessary to implement the IOD unit 112. The circuits 500 couple the radar unit 402, the sensor device 404, and the display and the sensors 403. The circuits 500 can transfer, store, send or receive data and commands, depending on their composition. In another embodiment, the circuits 500 include interfaces that will allow the various hardware devices to cooperate to transfer input data to the processor 506. Global Sequence of Operation FIG. 6 shows a sequence of steps of method 600 according to an example of the present invention. For ease of explanation, but without any limitation intended, the example of figure 6 is described in the context of the various embodiments of the invention described above. In one embodiment, the steps are initiated in the task 601, and the input data is received from the IOD unit 112 in step 602. The data of the IOD unit 112 may include information about the speed of the host vehicle, the range of the vehicle host from the vehicle obstacle, and the vehicle deviation obstacle from the azimuth of the host vehicle. Various methods for collecting and calculating this information are discussed in the patents incorporated by reference. Additionally, at least some information may be received from the host vehicle measuring equipment itself, such as the aforementioned speed measuring devices. In the task 604, the data received from the sensor device 404 of the IOD unit 112 are preferably filtered before any manipulation of the data, in order to standardize the received data. For example, in one embodiment, the sensor device 404 is a gyroscope. Because the drift of the gyroscope polarization varies, depending on the time elapsed during which the gyroscope has been "energized", the polarization must be filtered by processing the data received from the gyroscope using the filter 502 shown in "Fig. 5, as discussed above In one embodiment, the filter 502 processes the gyroscope data output using a discrete formulation for high pass filtering.The high pass filter output sequences are equal to: yn = exp (-T / t) * yn_1 + (ll / t) * xn - exp (-T / t) * x- ^ where T is the sampling interval, t is a constant related to the filter corner frequency, - xn represents the input sequences of gyroscope, and n represents the filter output sequences, preferably every 15 filter sequences are averaged to obtain four measures of the turning speed of the host vehicle 111 per second. random fluctuations caused by vibrations of the host vehicle 111 traveling along a non-uniform surface and by the internal noise to the gyroscope. A smaller or larger number of filter sequences can be averaged and the accuracy can be maintained, depending on the surface based on the amplitude and uniformity of the random fluctuations experienced by the IOD unit 112. If the desired data rate is small , for example of a few samples per second, even a low pass filter can be used. In task 606, the average turning speed for the host vehicle 111 is calculated by the processor 506 of the circuits 500 in the preferred embodiment of the invention. Although various methods can be used to calculate the average speed of turn, it is preferred that the average speed of turn? A-- be formed as: 15? Av = (? Y _) / 15. =? where y is the output sequence of the high pass filter, and the measurement is converted to units or radians per second. However, any method can be used to determine the average turning speed, and the measurement can be expressed in any unit of measurement. In task 608, the radius of curvature Rturn of the trajectory in which the host vehicle 111 is moving is determined. Preferably, the radius of curvature is calculated by the processor 506 as: where V is the speed of the host vehicle 111 measured in feet per second. Although a method is shown in which the radius of curvature can be calculated, any method for determining the radius can be used, and the measurement can be expressed in any unit of measurement. For each obstacle tracked by the radar of the present invention, an obstacle azimuth angle oti = R ± / (2 * Rturn) is calculated where R ± is the range of the ith obstacle that is being tracked by the IOD unit 112. In task 612, processor 506 determine whether or not an obstacle vehicle is in the path of host vehicle 111. The obstacle azimuth angle a- is determined and then compared to the reference azimuth angle.. Assuming that N number of targets are being tracked by the IOD unit 112, it is most feasible for an obstacle vehicle to be in the path of the host vehicle in the preferred embodiment if the processor 506 determines that. ± is equal to? X, where i = 1, 2, 3, ... N. In another embodiment, it is most feasible that the obstacle vehicle is in the path of the host vehicle if the processor 506 determines that |? - - a (e, where i = 1, 2, 3, ... N, and e is a constant In the preferred embodiment, e is equal to 0.4 degrees In an alternate embodiment, the constant e is selected by the processor 506 to accommodate errors in the azimuth output of the IOD 112 unit, the speedometer output, the cornering speed measurements, and other errors, based on the specific application of the invention In task 612, if more than one obstacle satisfies the previous inequality, then the 506 processor prioritizes the obstacle with the lowest rank R. as the primary interest. As would be obvious to a person skilled in the art, if the host vehicle 111 were traveling along a curved travel path, only the obstacle vehicle located on the side of the nearest vision to the obstacle vehicle needs to be considered. For a large radius trajectory, the obstacle azimuth angle OI. it takes a value close to zero so that, as expected for straight line displacement, the only targets that are considered for path determination are those in or near the view. The method ends in task 614. For example, Figure 7 shows a first obstacle vehicle (FOV) 720 that is on a path 715 of host vehicle 111. Host vehicle 111 is traveling in a direction shown by an arrow 714 on a lane 716 of a road 710. The IOD unit 112 of the host vehicle 111 transmits a radar beam 718 that extends from the front end of the host vehicle 111. The radar beam 718 is shown as encompassing the FOV 720 and a second obstacle vehicle (SOV) 722. The FOV 720 and the SOV 722 are moving in the same direction as the host vehicle 111, as also represented by an arrow 714. The FOV 720 is "seen" by the radar beam 718 as being in the path of the host vehicle 111 because the deflection angle 704 (the angle between the reference azimuth 702 and the azimuth 706 calculated by the processor 506J is zero, however, the radar beam 718 also "would" see SOV 722 as being in the path of host vehicle 111 for the same reason. To determine whether or not the FOV 720 is truly on the path 715 of the host vehicle 111, the processor 506 calculates the angle using the input data of the IOD unit 112, as described before. The angle is compared with the angle? by the processor 506 and the determination in the path is completed. In the preferred embodiment, WO would be equal to? for the FOV 720, and o? ? As a result, the processor 506 would determine that the FOV 720 is on the displacement path 715 of the host vehicle 111, but that the SOV 722 is not on the displacement path 715. The SOV 722 would be judged not only on the path of the host vehicle 111, regardless of the direction of travel of the SOV 722. Although the processor 506 performs the calculations and performs the determinations in the path in the preferred example indicated above, the processor 506 does not have to be dedicated to it. The processor 506 can also perform other functions not directly related to making an obstacle determination in the path. Moreover, the steps of calculating and arranging in interface can be carried out by other devices contained in the circuits 500. In another embodiment, the processor can be re-programmable. Data Storage Device Such a method, as described above, can be implemented, for example, by operating the IOD unit 112 to execute a sequence of machine-readable instructions.

These instructions reside in various types of data storage medium. In this regard, one aspect of the present invention concerns a manufacturing article, which comprises a data storage medium that tangibly incorporates a program of machine-readable instructions executable by the digital data processor 506 to carry out the above steps. of the method to perform the determination in the trajectory. This data storage means may comprise, for example, RAM contained in the storage unit 504 of the IOD unit 112. Alternatively, the instructions may be contained in another data storage medium, such as a magnetic storage disk. 802 data (figure 8). Whether they are contained in the IOD unit 112 or "elsewhere, the instructions may instead be stored in another type of data storage medium, such as a direct access storage device (e.g. , a "hard drive" of conventional type), magnetic tape, electronic read-only memory (for example, CD-ROM or WORM), an optical storage device (for example, WORM) or other means of data storage. In an illustrative embodiment of the invention, the machine readable instructions may comprise, for example, lines of code compiled in C ++ language. Other Forms of Embodiment While those which are presently considered to be the preferred embodiments of the invention have been shown, it will be apparent to those skilled in the art that various changes and modifications may be made herein without departing from the scope of the invention. the invention, as defined by the appended claims. Accordingly, it should be understood that the invention will not be limited by the specific embodiment illustrated, but only by the scope of the appended claims.

Claims (27)

1. REVINDICATIONS 1. An obstacle determination device in the path, comprising: (a) an input device through which a deviation of an obstacle from a reference azimuth can be determined; (b) a sensor device through which an average turning speed, a speed of displacement, and a radius of curvature of a path displaced by a host vehicle, where the average turning speed is determined as? a, can be determined. = (? and -) /? (= 1 where? Is a total number of samples used to determine the average turning speed having a value greater than 1, and y is a filter output for each sample, and (c) circuits coupled to the input device and sensor device for determining if the obstacle is in the travel path of the host vehicle 2. The device as defined in claim 1, wherein the circuits include a processor and a storage unit 3. The device as defined in FIG. claim 1 or 2, wherein the sensor device is a gyroscope 4. The device as defined in claim 3, wherein an initial polarization of the gyroscope is determined as GIB = where G ± is the sample reading at times 1 to 5. The device as defined in claim 4, wherein the circuits store the turning input for a period of time when the host vehicle is stationary and the input stores. nothing is used to determine the initial polarization of the gyroscope. 6. The device as defined in the claim 5, where the time period includes four integrals, each one measured from the time in which the turning input is generated for the first time, the integrals comprising: (a) 0 to 2 minutes; (b) 2-5 minutes; (c) 5-10 minutes; and (d) more than 10 minutes. 7. The device as defined in any of claims 4-6, wherein G ± is taken every 20 μsec and? equals 64. The device as defined in any of the preceding claims, wherein the circuits include a filter used to filter the output of the gyroscope. 9. The device as defined in claim 8, wherein the filter uses a discrete formulation, in which? = exp (-T / t) * yn_? + (ll / t) * xn - exp (-T / t) * xn_1, where T is a sampling interval, t is a constant related to a filter corner frequency, xn represents gyroscope input sequences with any polarization removed, and already represents a filter output sequence. The device as defined in claims 8 or 9, wherein the radius of curvature is determined as Rturn = V /? Av, where V is a speed of travel of the host vehicle. The device as defined in claim 10, wherein the circuits for determining whether the obstacle is in the path displaced by the host vehicle comprise: (a) means for calculating an angle, ±, where a ± = Ri / (2) * Rturn), where R ± is the rank to the ith obstacle; (b) means to compare ± with?, where? it is a deviation from the obstacle in a given time from a reference azimuth; and (c) means for determining if the obstacle is in the trajectory of the host vehicle based on the comparison of? with «i. The device of claim 10, wherein the circuits for determining whether the obstacle is in a path of the host vehicle comprise: (a) means for calculating an angle, ±, where? Í ± = R ± / (2 * Rturn) , where R ± is the rank to the ith obstacle; (b) means to compare a cross-obstacle range Rcl, where Rci is the cross-over range to the ith obstacle, and where R-i = R ± * (? i - ¿), where? is the deviation of an obstacle at a given time from the reference azimuth; and (c) means for determining if the obstacle is in the path of the host vehicle by comparing Rci with L, where L is equal to half the width of the path displaced by the host vehicle. 13. The device as defined in claim 12, where it is determined that the obstacle is in the trajectory of the host vehicle if | Rcl | = L. 14. The device as defined in claim 11, where it is determined that the obstacle is in the path of the host vehicle if? = ax, where i equals the total obstacle number from 1 to? 15. The device as defined in claim 11, wherein it is determined that the obstacle is in the path of the host vehicle if |? - I heard ± | (e, where i equals the total obstacle number from 1 to? and amp.; It is a constant. 16. The device as defined in claim 15, wherein the obstacle with the lowest value for Rx will be prioritized if |? - x | (e is satisfied for more than one of the obstacles from 1 to 17. 17. A method for determining obstacles in the path, comprising the steps of: (a) receiving an input through which a deviation can be determined of an obstacle from a reference azimuth, (b) receiving a turn input for a host vehicle from which an average speed of turn, a speed of displacement, and a radius of curvature for the trajectory displaced by a host vehicle; (c) calculate the average speed of turn, where the average speed of turn is determined as? a. = (? Y?) /? 1 = 1 where? is a total number of samples used to determine the average speed of turning having a value greater than 1, and y ± is a filter output for each sample, (d) determining the speed of displacement of the host vehicle, (e) calculating the radius of curvature for the displaced path, (f) deter mine a range of the host vehicle to each obstacle; (g) determining a deviation of each obstacle from the reference azimuth; (h) calculate an angle x; and (i) determining the obstacle is in a trajectory of the host vehicle using the angle ±. 18. The method as defined in claim 17, wherein determining if the obstacle is in the trajectory of the host vehicle includes calculating a range crossed to the obstacle using the angle ±. The method as defined in claims 17 or 18, including the step of filtering the turn input to eliminate any initial polarization inherent in any instrument used to measure the cornering input. The method as defined in claim 19, wherein the cornering input is received from a gyroscope, and the initial polarization of the gyroscope is determined as n GIB = (? G ^ / 26 where G ± is the sample reading in times 1 through 21. The method as defined in claim 19, including the step of storing the turn input for a period of time when the host vehicle is stationary, and using the stored turn input to determine the polarization initial of the gyroscope 22. The method as defined in claim 19, wherein the time period includes four integrals, each measured from the time the turn input was generated for the first time, the integrals comprising: (a) 0 to 2 minutes, (b) 2 to 5 minutes, (c) 5 to 10 minutes, and (d) more than 10 minutes. 23. The method as defined in claim 19, where G_ is taken every 20 μsec and? equals 64. - 24. A manufacturing article, comprising a data storage medium that tangibly incorporates a program for machine-readable instructions executable by a digital processing apparatus to carry out method steps for determining obstacles in the path, said method steps comprising: (a) receiving an input through which a deviation of an obstacle can be determined from a reference azimuth; (b) receiving a turning input for a host vehicle from which an average turning speed, a traveling speed, and a radius of curvature for the path displaced by a host vehicle can be determined; (c) calculate the average speed of turn, where the average speed of turn is determined as n? -v = (? y _) /? where ? is a total number of samples used to determine the average turning speed having a value greater than 1, and y_ is a filter output for each sample; (d) determining the travel speed of the host vehicle; (e) calculating the radius of curvature for the displaced path; (f) determining a range of the host vehicle to each obstacle; (g) determining a deviation of each obstacle of the reference azimuth; (h) calculate an angle x; and (i) determining whether the obstacle is in a trajectory of the host vehicle using the angle OIX. 25. The article of manufacture as defined in claim 24, including the step of filtering the turn input to eliminate the initial bias inherent in any instrument used to measure the cornering input. - 26. The article of manufacture as defined in claims 24 or 25, including the step of storing the turn input for a period of time when the host vehicle is stationary, and using the stored turn input to determine the initial polarization of the gyroscope. 27. The article of manufacture as defined in claim 26, wherein the time period includes four integrals, each measured from the time that the turn input was first generated, the integrals comprising: (a) 0 a 2 minutes; (b) 2 to 5 minutes; (c) 5 to 10 minutes; Y (d) more than 10 minutes.