124 results about "Distance model" patented technology

The invention discloses a vehicle safety driving early warning method based on vehicle internet. Vehicle information data is sent to a network background server through a vehicle-mounted wireless communication unit, the network background server acquires information data of dangerous points on a road section where a vehicle is located according to the vehicle information data and sends the information data at the dangerous points on the road section to the vehicle-mounted wireless communication unit, a vehicle-mounted central processing unit compares obtained dangerous point information with self-vehicle information, a safety distance model is called to generate early warning parameters, and a vehicle-mounted alarm unit, a vehicle-mounted display unit and an electronic control braking system are controlled to perform early warning response. The vehicle safety driving early warning method based on the vehicle internet has the advantage that a network background server terminal provides the dangerous point information for a vehicle-mounted terminal, the vehicle-mounted terminal acquires and analyzes vehicle geographical position information and the dangerous point information on the road section where the vehicle is located in real time, the vehicle-mounted alarm unit, the vehicle-mounted display unit and the electronic control braking system are controlled to perform the early warning response, and the vehicle safety driving early warning method based on the vehicle internet has reliability and high efficiency of vehicle network data communication.

A universal Automatic Train Protection ATP vehicle mounted system and mode control method. The invention mainly uses digital signal processing and safe redundant control technology, designs a safe Protection Automatic control system which can receive many varieties of ground vehicles information transmission modus, realize the combination of the train speed steps control and the first-order speed-distance model curve and realize the generalization of vehicle automatic protection system vehicle mounted equipments. And the ground vehicles information transmission modus consists of analog and digital track circuit, responder, GSM-R transmission, 2.4GHz wireless transmission, etc. the safe protect control is the safe braking model control using the combination of speed steps and first-order speed-distance model curve. The system mainly consists of power module, ground vehicles information transmission reception module, central processing module, recording module and man-machine interface MMI module, etc. The beneficial result is getting a solving program for users on the base of reducing construction costs and intercommunicating transport operation.

The invention discloses an application method of a Hamming distance model on SM4 cryptographic algorithm lateral information channel energy analysis and based on S box input. The application method is characterized in that the Hamming distance model is established by selecting an S box or a round function as an attacking point in the process that the SM4 cryptographic algorithm lateral information channel energy analysis is carried out, the input of the S box is used as an initial state v1 of the Hamming distance model, the output of the S box is used as subsequent state v2 of the Hamming distance (HD (v1, v2)) model when the S box is attacked, and the output / input of the round function is used as the subsequent state v2 of the Hamming distance (HD (v1, v2)) model when the round function is attacked. The method can be applied to CPA / DPA lateral information channel energy analysis of the SM4 cryptographic algorithm. Correlation between a correct guess secret key and energy information is improved, and validity and success rate of the analysis are enhanced.

Rapid calibration of a TOF system uses a stationary target object and electrically introduces phase shift into the TOF system to emulate target object relocation. Relatively few parameters suffice to model a parameterized mathematical representation of the transfer function between measured phase and Z distance. The phase-vs-distance model is directly evaluated during actual run-time operation of the TOF system. Preferably modeling includes two components: electrical modeling of phase-vs-distance characteristics that depend upon electrical rather than geometric characteristics of the sensing system, and elliptical modeling that phase-vs-distance characteristics that depending upon geometric rather than electrical characteristics of the sensing system.

The invention discloses an automatic driving lane changing preparation and execution integrated trajectory planning method. The method comprises the following steps: establishing a motion trajectory model of a lane changing vehicle in a lane changing preparation process; introducing a cubic polynomial to establish a trajectory equation of the lane changing vehicle in a lane changing execution process; establishing a safe distance model and a safe speed model in the lane changing preparation and lane changing execution processes; and establishing an integrated trajectory optimization model, andoptimizing the time and the acceleration in the lane changing preparation and execution processes to obtain a most trajectory meeting safety, efficiency and comfort requirements. An integrated lane changing trajectory set is established according to the vehicle motion characteristics, a safe lane changing trajectory set meeting lane changing safety requirements is chosen by using safety constraints, and finally the trajectories are optimized by considering the lane changing comfort and efficiency to obtain the optimal integrated trajectory meeting safety, comfort and efficiency requirements.The optimal lane changing trajectory planned in the invention has a high service level, and ensures that passengers have high comfort experiences and high efficiency experiences.

The invention relates to a multi-intelligent agent based unmanned electric car automatic overtaking system and method. The automatic overtaking system includes a vehicle-mounted sensor for acquiring front traffic information of an unmanned electric car. The automatic overtaking method includes: establishing a minimize safe distance model on the basis of feature information of a car and a surround environment thereof extracted by a vehicle-mounted sensing system and a V2X communication system; setting a sine function form as a base function of an automatic overtaking desired path, and dynamically planning an automatic overtaking desired track of the unmanned electric car in real time; adopting a self-adaption fuzzy slide mode control technique to solve the desired speed and the desired yaw velocity of overtaking of the unmanned electric car on the basis of a deviation between the desired overtaking path and an actual path; adopting a multi-intelligent agent genetic optimization algorithm to calculate out the required longitudinal and horizontal force of each wheel of the unmanned electric car; and establishing a mapping model from the longitudinal and horizontal forces of the wheels of the unmanned electric car to the desired slip angle and slip rate, and achieving execution control of the longitudinal and horizontal force of tires the unmanned electric car.

The invention discloses an application of selecting round key XOR input to perform side-channel power analysis of an SM4 cryptographic algorithm. The application is characterized in that in the process of the side-channel power analysis of the SM4 cryptographic algorithm, S boxes or round functions are selected to serve as attack points to establish a Hamming distance (HD) model, the round key XOR input is taken as a preceding state v1 of the HD model, and when the S boxes are attacked, the subsequent state v2 of the HD (v1, v2) model is S box output; and when the round functions are attacked, the subsequent state v2 of the HD (v1, v2) model is output/input of the round functions. The method can be applied to the side-channel power analysis of a CPA (correlation power analysis) and DPA (differential power analysis) of the SM4 cryptographic algorithm. With the adoption of the method, the correlation between a right guessing secret key and a power message is improved, the effectiveness of the analysis is enhanced, and the success rate is increased.

The invention discloses a vehicle cooperative following method based on vehicle-to-vehicle communication. The method comprises the steps of (S1) collecting the driving data of a vehicle and the driving data of a front vehicle, (S2) establishing a variable time length safety distance model based on the driving data of the vehicle and the driving data of the front vehicle, (S3) establishing a vehicle cooperative following model based on the driving data of the front vehicle, the driving data of the vehicle and the variable time length safety distance model, and (S4) calculating an ideal acceleration of the vehicle according to the vehicle cooperative following model and transmitting the ideal acceleration to an actuator such that the actual acceleration of the vehicle changes following an ideal acceleration value. According to the method, through the vehicle-to-vehicle communication, the information of the front vehicle is obtained, the variable time length safety distance model considering the information of the front vehicle is established with the combination of the driving information of the vehicle, the ideal acceleration is transmitted to a vehicle dynamics model, a throttle and a brake are controlled such that the actual acceleration of the vehicle changes following the ideal acceleration value, the maintenance of an ideal distance between vehicles is achieved, the vehiclestably and reliably drives following the front vehicle, and the driving safety is improved.

The invention discloses a multi-vehicle collaborative lane changing control method based on vehicle-vehicle communication. In view of complicated scenes of multiple lanes, simultaneous lane changing of multiple vehicles and variable motions of go-straight vehicles, a multi-vehicle collaborative lane changing control strategy is provided, and a safety distance model for the go-straight vehicles under the variable acceleration condition and a safety distance model between two lane changing vehicles are built. Through adopting a quintic polynomial lane changing track, taking the track length andthe comfort as objective functions, and taking the vertical and horizontal speeds of the vehicles and the like as constraint conditions, a desired lane changing track is obtained by utilizing an optimization solution method. In the lane changing process, a safe distance is calculated according to real-time information of the lane changing vehicles and the go-straight vehicles, and the track is re-planned in danger, so that collision accidents can be avoided, and meanwhile, the passing efficiency is improved.

The invention discloses an automobile rear-end collision prevention early warning method and system. The system comprises a wireless communication dedicated short range communication (DSRC) device arranged at a roadside, and a vehicle-mounted wireless communication device, a data acquisition unit and a vehicle-mounted terminal which are installed on a vehicle, wherein the data acquisition unit is internally provided with a data acquisition module, a GPS module and an acceleration sensor. Through the DSRC device, wireless communication interaction between vehicles and between vehicles and roads is realized. The vehicle-mounted terminal calculates a safety distance between a vehicle and a front vehicle by use of a minimum safety distance model based on vehicle-road cooperation, an actual distance between the vehicle and the front vehicle is calculated through position information, whether a read-end collision risk exists is determined, if the read-end collision risk exists, a risk prompt is displayed on an interface of the vehicle-mounted terminal, and an alarm is given through sound. According to the invention, the cost of the read-end collision prevention early warning system is reduced, and the early warning accuracy is improved. The system has the advantages of low cost, small volume, accurate early warning and the like, thereby being applied to various road conditions.

The invention relates to the field of mobile Internet application security and discloses an authentication method of an intelligent bracelet and an intelligent mobile terminal for implementing safety binding and pairing of the bracelet and the mobile terminal and utilizing the bracelet to implement access control of the mobile terminal; a Diffie-Hellman protocol is improved in a binding initialization scheme, a time stamp is added and an MAC (Media Access Control) address of the bracelet and an IMEI (International Mobile Equipment Identity Number) of the intelligent mobile terminal are combined to carry out pairing; a communication signal distance model is utilized to prevent man-in-the-middle attack during binding initialization. In an authentication scheme, after the mobile terminal is successfully authenticated by utilizing the bracelet, a user can visit protected information in the mobile terminal, so that the dynamic access control of the mobile terminal is implemented; an authentication process is automatically completed, so that usability of the user is improved; an authentication protocol is based on Hash transform and symmetric encryption algorithms so as to have low influence on the performance. Authentication parameters are timely updated after each authentication, so that safety is increased. The method is suitable for access control of privacy information of the mobile terminal.

The invention discloses a self-adaptive cruise control method based on a safe distance model with driver car-following characteristics, which mainly comprises the following steps: 1, based on the analysis of the motion states between the cars, a safe car-following distance model conforming to the diver car-following characteristics is designed; 2, a fourth-order continuous car-following model of an ACC system is established; 3, the safe car-following distance model established in step 1 is used as the following target of the upper layer decision algorithm of the adaptive cruise system. According to the invention, aiming at the problem that the expected safe distance selected by the upper layer control algorithm of a prior adaptive cruise system does not confirm to the actual driver characteristics, the safe car-following distance model is redesigned and applied to the upper layer decision algorithm, so that the control characteristics of the adaptive cruise system is closer to the control behaviors of a skilled driver and the acceptance and utilization rate of the system are improved.

The invention discloses an airborne SAR (synthetic aperture radar) imaging method suitable for a large squint angle. The method comprises the following steps of: (1) establishing an echo signal model; (2) performing signal imaging by the steps of: (2-1) performing distance fast Fourier transform and azimuth fast Fourier transform on a point target signal; (2-2) performing distance inverse Fouriertransform and performing accurate treatment on the phase of the signal; (2-3) multiplying the result by a Chirpscaling factor; (2-4) performing distance Fourier transform; (2-5) multiplying the result by a distance compensation factor; (2-6) performing distance inverse Fourier transform; (2-7) multiplying the result by an azimuth compensation factor; and (2-8) performing azimuth inverse Fourier transform to obtain a compressed SAR image signal. In the method, by imaging the point target under a large squint angle, a good peak-sidelobe ratio and an integral-sidelobe ratio can be obtained; a relatively high spatial resolution can be obtained in the distance direction and azimuth direction by use of the SAR pulse compression technology and the synthetic aperture technology; and moreover, themethod performs distance relocation correction in a time domain, simplifies an echo signal distance model, reduces the two-dimensional coupling quantity, adopts accurate phase unwrapping, realizes accurate correction of the signal and has a relatively high processing speed.

The invention provides an intelligent networking car coordinated lane-changing control method based on a wireless communication technique, and belongs to the technical field of intelligent traffic/car active safety control. By adoption of the intelligent networking car coordinated lane-changing control method based on the wireless communication technique, impact accidents caused by man-made judgment errors in the vehicle lane-changing process can be avoided, and the car driving safety is guaranteed. The intelligent networking car coordinated lane-changing control method is achieved based on the intelligent networking car technique, and comprises the steps that firstly, driving states and driving intentions of surrounding vehicles are obtained through a wireless communication unit; a longitudinal safety distance model is established according to vehicle lane-changing motion characteristics and relative positions of the vehicles on different lanes; a lane-changing control strategy based on a fuzzy control theory is proposed; expected acceleration values of a vehicle under different traffic scenes during constant-speed running or uniform-acceleration running of the vehicle are calculated, and the speed control of the target vehicle in the lane-changing process is completed; and expected acceleration values of the surrounding vehicles are calculated at the same time, and the purpose of avoiding the impact accidents in the lane-changing process of the vehicle is achieved through coordinated control over the lane-changing vehicle and the surrounding vehicles.

The invention discloses a vehicular access synergism anti-collision pre-warning system based on V2X. Aiming at judgment links of an anti-collision pre-warning decision in the beyond visual range of anintelligent connected vehicle, in combination with a V2X communication technology and an inertial navigation technology, an improved safe distance model is designed, and an anti-collision pre-warningsystem of the intelligent connected vehicle is constructed. A V2X communication module is mainly used for being responsible for data communication, including data broadcasting of the vehicle, detection of data of surrounding vehicles, and receiving of roadside end road traffic information; a positioning module comprises a GPS/BD sensor for obtaining position data of the vehicle, including the data of longitude and latitude, course angle, speed, elevation and the like; the sensors such as a posture data module, an accelerometer and a gyroscope are mainly used for obtaining posture data of thevehicle, including the data of vehicle acceleration, rotation angle and the like; and an inertial navigation module has the main functions of reducing a data cycle and improving the accuracy by usingan inertial navigation algorithm by utilizing the data of the sensors such as a GPS/BD module, the accelerometer and the gyroscope.

The invention discloses an automobile lane change collision avoidance control method, and belongs to the field of automobile active safety. Automobile related information and external environment related information are collected by related sensors on an automobile, the related information is input to an electronic control unit (ECU), and the ECU analyzes signals of all the sensors, determines the automobile driving emergency situation, rapidly schedules a lane change route, and establishes a longitudinal least safety distance model. According to the scheduled route and the safety distance model, the opening degree and braking force of a throttling valve are reasonably controlled; a steering motor is controlled at proper position so that the automobile can be driven along the scheduled route, and the input amount of a yaw velocity sensor is detected at any time; on the premise of ensuring stability, a steering wheel is adjusted to rotate to the motor, it is ensured that the automobile track is well tracked, and the aim of collision avoidance is achieved.

The invention discloses a self-adaptive autonomous emergency brake (AEB) control algorithm based on road adhesion. The self-adaptive autonomous emergency brake control algorithm based on the road adhesion predicates collision risk between a vehicle and a forward obstacle though obtaining forward obstacle information, information of the vehicle and a road adhesion coefficient and makes a final pre-warning and autonomous braking decision by taking control input of a driver into consideration so as to remind the driver of adopting forward collision avoidance control or avoid collision between the vehicle and the forward obstacle or reduce collision degree between the vehicle and the forward obstacle by using autonomous braking interference if necessary. According to the self-adaptive autonomous emergency brake control algorithm based on the road adhesion, on the premise of not changing the configuration of the existing vehicle-mounted sensor, the road adhesion coefficient is estimated in real time; the pre-warning and autonomous braking opportunity can be automatically adjusted in a safe distance model according to the road adhesion coefficient so that the forward collision avoidance safety on road surfaces with various road adhesion coefficients is ensured and false alarm or false brake interference is avoided; driving safety and good driving experience are both achieved; and during driver brake interference, the self-adaptive autonomous emergency brake control algorithm based on the road adhesion can apply necessary brake assistance according to the calculated collision risk.

The invention discloses a vehicle safety anti-collision control method combining safety distance and collision time, comprising the following steps of establishing a vehicle safety distance model; establishing a vehicle safety collision time model; and performing vehicle safety anti-collision decision. According to the method of the invention, an early warning distance is divided into three critical distances, namely a critical safety distance, a critical danger distance and a critical infinitesimal distance. Different safety prevention measures are provided for different distance phases, including safe driving tips, warnings, primary braking, secondary braking and emergency braking. Not only can ride comfort reduction caused by early braking be prevented, but also vehicle collision causedby delayed braking can be avoided. The method of the invention combines a safety distance model and a collision time model, which complement each other's deficiencies. The safety collision time modelcan compensate for the recognition error of a vehicle-mounted sensor on the safety distance; the safety distance model can make up for the infinite problem of TTC calculated by the safety collision time model.

The invention discloses a vehicle-mounted laser scanning data-based road surface point cloud strength enhancing method. The method comprises the following steps of: S1, obtaining a road surface pointcloud, a wheel path line and a distance from a laser point in the road surface point cloud to the wheel path line on the basis of vehicle-mounted laser scanning data, and segmenting the road surface point cloud; and S2, taking road surface point cloud segments as processing units to carry out the following steps of: 21, constructing an original distance model function and a reference distance model function, 22, carrying out strength correction on the laser point by adoption of ratio method and a difference value method, 23, carrying out strength conversion on the laser point, and 24, carryingout strength denoising on the laser point by adoption of a multi-filter integration method, so as to complete laser point strength enhancement of each road surface point cloud segment in the road surface point cloud. Compared with the prior art, the method is capable of remarkably enhancing the strength differences between different target materials of road surfaces and eliminating the strengthennoise in local homogeneous areas.

The invention discloses a method for target correlation and track generation of an image sequence. The method comprises the steps that a multistage correlative mechanism is designed, multiple static features and dynamic features of targets are extracted stage by stage, and different target affinity distance models are formed on different correlation stages, so that the multiple features of the targets are fully comprehended to conduct data correlation, and the accuracy of correlation is improved; meanwhile, based on a data correlation result, in the same image background, matched target center points are connected stage by stage, each obtained track section expands to the two ends continuously, and finally a complete motion track of each target is obtained. According to the method, various simple features of the targets are extracted stage by stage, so that multi-target correlation and track generation of a single-camera video are achieved reliably and rapidly, and the calculated amount is extremely small.

The invention provides an automobile and pedestrian anti-collision intelligent control system and method based on pedestrian and automobile cooperation. The control system is provided with an automobile-mounted sensor, a road information acquisition module, a microprocessor, an early warning device, a dangerous zone difference module, an expected acceleration generating module and a braking control module. The control method includes the steps that information of an automobile and surroundings of the automobile is acquired, and information characteristics of pedestrians in front of the automobile are extracted; a safe distance model of the automobile and the pedestrians is established, dangerous zone judging and differentiating criteria are designed, an early warning is given in an early warning zone to remind a driver, and auxiliary braking control is conducted in a dangerous zone; based on the longitudinal motion characteristics of the automobile and the pedestrians, a pedestrian and automobile interval longitudinal kinetic model and an automobile acceleration response model are established, and a pedestrian and automobile coupling kinetic model is comprehensively generated; the expected acceleration needed for avoiding pedestrian and automobile collisions is dynamically planned in real time; and a nerve fuzzy sliding formwork braking controller is designed, commands for braking pressure are adjusted to complete tracking of the expected acceleration, and active protection and anti-collision conducted by the automobile to the pedestrians are achieved.

The embodiment of the invention provides an automatic focusing method and a PTZ (Pan/Tilt/Zoom) camera. The method is applied to the PTZ camera. The method comprises the steps of calculating target object distance from a lens of the PTZ camera to a monitored target monitoring plane based on a pre-established space object distance model, wherein a space plane equation of a reference monitoring plane is recorded in the space object distance model, and the reference monitoring plane is an equivalent plane of the target monitoring plane; determining position information of a focusing motor of thePTZ camera based on the target object distance, a current multiplying power of the PTZ camera and a preset relationship table, wherein a corresponding relationship among the object distance, the multiplying powers and the positions of the focusing motor is recorded in the preset relationship table when a focus of the lens of the PTZ camera falls on an image sensor of the PTZ camera; and driving the focusing motor to the position corresponding to the position information. Through application of the embodiment of the invention, the PTZ camera can be rapidly and automatically focused.

The invention provides a high-precision microwave radar ranging system which can be used for detecting multiple targets in a close range and a long range and at different angles, different ranging calculations can be carried out according to different distance models, reliability is improved through a radar dead angle auxiliary detection unit, and safety accidents can be reduced to the largest extent.

The invention discloses an urban indoor and outdoor integration three-dimensional scene construction and space adaptive navigation method, which comprises the following steps: on the basis of ALS (Approach and Landing Simulator) point cloud data, constructing an urban space model; creating an indoor three-dimensional scene system and a texture database; carrying out indoor and outdoor integration scene construction and model structure optimization: carrying out three-dimensional model and information integration based on Google Earth and SketchUP platforms; selecting a QR (Quick Response) Code two-dimensional code to design an anchor point; constructing an anchor point-user distance model; and carrying out adaptive indoor and outdoor positioning switching. The method has the advantages that an urban indoor and outdoor integration model is constructed by the ALS cloud point data, an accurate indoor and outdoor space scene is constructed and integrated on the Google Earth platform by a modeling system, WiFi and a two-dimensional code technology are combined to develop an indoor and outdoor space adaptive navigation service, the construction of the urban indoor and outdoor integration three-dimensional scene model and indoor and outdoor real-time positioning are realized, positioning accuracy is high, and space positioning information is provided.