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This paper presents a Forward Collision Detection approach based on Elevation Map using a Dense Stereo-Vision system. Once we have the 3D information about the road surface, we extract a set of obstacle delimiters by exploiting the elevation structure through the radial scanning method. Taking in account the car mechanical and movement parameters,...
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... If no error or unmatched codes are found, the input data codes are decoded and then transferred to the output pins. The VT pin also goes high to indicate a valid transmission [9]. The 212 series of decoders are capable of decoding information's that consist of N bits of address and 12_N bits of data of this series, the HT12D is arranged to provide 8 address bits and 4 data bits, and HT12F is used to decode 12 bits of address information. ...
This paper explores the possibility of providing traffic control signals through radio frequency (RF) transmission or by other means of wireless data communication and thereby reduce road accidents. Additional advantages can be reducing the car speed or stopping car at speed breakers, no entry zones or police barricade. This system if adopted by some state can effectively reduce the number of road accidents caused by speeding vehicles losing control of the vehicle at speed breakers or by driver's negligence towards traffic signals [1]. The primary model of this system consists of a microcontroller controlled RF transceiver module, electronic controller unit (ECU) used in vehicles. In the system proposed the traffic sign boards including control signals are replaced with RF transmitters transmitting the specified coded data (about the traffic signal) for the traffic control receiver unit integrated in the in the car where the receiver unit is connected to the ECU and to display unit on the dashboard of the car which on coming in vicinity of the particular traffic signal. For some specific signals, like the speed breaker, police barricade. In these zones if the response of the driver within specified time duration is not achieved such as to reduce speed or stop down, then the controller unit takes control of car transmission and performs the specified operation. In this paper a novel approach is described to embed a hardware system into a vehicle, for a transmission range of 50mts to control the vehicle in the various zones. The experimentation provides complete the hardware description and working model for dynamic driving assistance.
... If no error or unmatched codes are found, the input data codes are decoded and then transferred to the output pins. The VT pin also goes high to indicate a valid transmission [9]. The 212 series of decoders are capable of decoding information's that consist of N bits of address and 12_N bits of data of this series, the HT12D is arranged to provide 8 address bits and 4 data bits, and HT12F is used to decode 12 bits of address information. ...
This paper explores the possibility of providing traffic control signals through radio frequency (RF) transmission or by other means of wireless data communication and thereby reduce road accidents. Additional advantages can be reducing the car speed or stopping car at speed breakers, no entry zones or police barricade. This system if adopted by some state can effectively reduce the number of road accidents caused by speeding vehicles losing control of the vehicle at speed breakers or by driver's negligence towards traffic signals [1]. The primary model of this system consists of a microcontroller controlled RF transceiver module, electronic controller unit (ECU) used in vehicles. In the system proposed the traffic sign boards including control signals are replaced with RF transmitters transmitting the specified coded data (about the traffic signal) for the traffic control receiver unit integrated in the in the car where the receiver unit is connected to the ECU and to display unit on the dashboard of the car which on coming in vicinity of the particular traffic signal. For some specific signals, like the speed breaker, police barricade. In these zones if the response of the driver within specified time duration is not achieved such as to reduce speed or stop down, then the controller unit takes control of car transmission and performs the specified operation. In this paper a novel approach is described to embed a hardware system into a vehicle, for a transmission range of 50mts to control the vehicle in the various zones. The experimentation provides complete the hardware description and working model for dynamic driving assistance.
... More sophisticated approaches comprise piecewise planar representations [Labayrade et al., 2002], quadratic surfaces [Nedevschi et al., 2008], or clothoid based models [Nedevschi et al., 2004]. Wedel et al. [2009] employ a cubic B-Spline (see Section 2.7) parameterized along the longitudinal axis of the vehicle to model the curvature in longitudinal direction. ...
... One can categorize occupancy grids in two groups. First, there are deterministic occupancy grids which can be understood as 2d histograms counting the number of 3d measurements aligned to a specific cell without modeling the noise properties [Franke et al., 1997, Nedevschi et al., 2008. On the other hand, stochastic or probabilistic occupancy grids considering the sensor uncertainty of incoming range measurements to update the occupancy statements of the cells. ...
... In [Nedevschi et al., 2008] and [Nedevschi et al., 2009] the authors employ a deterministic Cartesian occupancy grid. The grid cells are labeled as road, traffic isle or obstacle by threshold based classification considering the highest point per cell and the point density. ...
This thesis presents an approach for the detection and reconstruction of street surfaces and boundaries from depth image sequences.
Active driver assistance systems which monitor and interpret the environment based on vehicle mounted sensors to support the driver embody a current research focus of the automotive industry. An essential task of these systems is the modeling of the vehicle's static environment. This comprises the determination of the vertical slope and curvature characteristics of the street surface as well as the robust detection of obstacles and, thus, the free drivable space (alias free-space). In this regard, obstacles of low height, e.g. curbs, are of special interest since they often embody the �first geometric delimiter of the free-space.
The usage of depth images acquired from stereo camera systems becomes more important in this context due to the high data rate and affordable price of the sensor. However, recent approaches for object detection are often limited to the detection of objects which are distinctive in height, such as cars and guardrails, or explicitly address the detection of particular object classes. These approaches are usually based on extremely restrictive assumptions, such as planar street surfaces, in order to deal with the high measurement noise.
The main contribution of this thesis is the development, analysis and evaluation of an approach which detects the free-space in the immediate maneuvering area in front of the vehicle and explicitly models the free-space boundary by means of a spline curve. The approach considers in particular obstacles of low height (higher than 10 cm) without limitation on particular object classes. Furthermore, the approach has the ability to cope with various slope and curvature characteristics of the observed street surface and is able to reconstruct this surface by means of a flexible spline model.
In order to allow for robust results despite the flexibility of the model and the high measurement noise, the approach employs probabilistic models for the preprocessing of the depth map data as well as for the detection of the drivable free-space. An elevation model is computed from the depth map considering the paths of the optical rays and the uncertainty of the depth measurements. Based on this elevation model, an iterative two step approach is performed which determines the drivable free-space by means of a Markov Random Field and estimates the spline parameters of the free-space boundary curve and the street surface. Outliers in the elevation data are explicitly modeled.
The performance of the overall approach and the influence of key components are systematically evaluated within experiments on synthetic and real world test scenarios. The results demonstrate the ability of the approach to accurately model the boundary of the drivable free-space as well as the street surface even in complex scenarios with multiple obstacles or strong curvature of the street surface. The experiments further reveal the limitations of the approach, which are discussed in detail.
... In general, the algorithms use 3D space and disparity space based techniques to calculate road surface and discover hurdles on the roads [5]. Difficult situations on the roads like tunnels, narrow bridges, etc. can be described by the 3D model by plotting a polyhedron as such models are usually structured [6]. The distance detection procedures of stereovision technique are also very important in vehicles to inform the driver while driving the vehicle. ...
Stereovision based on 3D environment reconstruction provides a true picture of real world situations for detection of objects’ locations. This approach has specific use in the scenarios like identifying traffic jams on the roads, locating curves and bends on the roads, finding obstacles in the construction sites, etc. This paper describes different methods used in stereovision to detect images like use of trinocular stereovision, calculating correlation between left and right contours for achieving accuracy, use of prior information with intrinsic and extrinsic parameters, detection of side lane and 3D points of guardrails and fences, use of dense stereovision information, especially in urban environment. The paper also discusses Forward Collision Detection method that uses Elevation Map with Dense Stereovision, tracking of multiple objects using two-level approach and building an enhanced grid that involves obstacle cells. Hybrid dense stereo engine, which is used in urban detection scenarios is also discussed in the paper along with a solution of lane estimation in different situations using particle filtering method. Pattern matching using 3D image for pedestrian detection and lane estimation based on the particle filtering with greyscale images are also explored. The use of the rectangular digital elevation map for transforming stereo based information and the methodology used to enhance the sub pixel accuracy are also part of the paper.
This paper presents the specifications and architecture for a stereovision sensor to be used in intersection assistance. The intersection problem imposes a wide field of view, reasonable accuracy for the typical intersection length, and fast response time. The image and 3D data provided by the low level routines are used to generate two kinds of environment descriptions - an unstructured description, composed of elevation maps, occupancy grids, and polylines delimiting obstacle areas and curbs, and a structured description, composed of lanes, cuboidal objects, and classified pedestrians. The descriptions can be further combined, and additional data sources can be used, in order to provide a complete and accurate description of the intersection.
