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Technical Paper

Application Oriented Testcase Generation for Validation of Environment Perception Sensor in Automated Driving Systems

2018-08-07
2018-01-1614
Validation is one of the main challenges in development of automated driving systems (ADS). Due to the complexity of these systems and the various influence factors on their functional safety, current testcase generation methods can hardly guarantee the completeness and effectivity of the validation on system level. Separate validation of system components is a way to make system approval possible. In this paper, an approach is presented to generate deductively testcases for the validation of the environment perception sensors, which are the most essential components of ADS. This approach is originated from the model-based testing method, which is commonly used to validate software-based systems and extended by considering various external influence factors as follows: By modeling and analyzing applications in ADS, application oriented usecases of perception sensors are first derived.
Technical Paper

Road Sign Recognition System Based on Wavelet Transform and OPSA Point Set Distance

2018-08-07
2018-01-1609
Signage recognition is one of the hot topics in recent years. It has important applications in intelligent traffic and autonomous driving of smart cars. This paper designs a road marking recognition method combining OPSA point set distance and wavelet transform. The method consists of three main phases: 1) image denoising, restoration, 2) feature extraction, and 3) image recognition. First, a Gaussian-smoothing filter used to attenuate or remove irrelevant information in the image, enhance related information in the image, and achieve image denoising. In the feature extraction stage, the feature extraction and recognition method based on wavelet transform adopted to overcome the deficiency of the traditional Fourier feature extraction method, ensure that high frequency information is not lost, and low frequency information is not lost. Finally, the OSPA point set used to identify distance markers.
Technical Paper

A Localization System for Autonomous Driving: Global and Local Location Matching Based on Mono-SLAM

2018-08-07
2018-01-1610
The utilization of the SLAM (Simultaneous Localization and Mapping) technique was extended from the robotics to the autonomous vehicles for achieving the positioning. However, SLAM cannot obtain the global position of the vehicle but a relative one to the start. For sake of this, a fast and accurate system was proposed to obtain both the local position and the global position of vehicles based on mono-SLAM which realized the SLAM by using monocular camera with a lower cost and power consumption. Firstly, the rough latitude and longitude of current position was obtained by using common GPS without differential signal. Then, the Mono-SLAM operated on the consecutive video frames to generate the localization and local trajectory and its accuracy was further improved by utilizing the IMU information. After that, a piece of Map centered in the rough position obtained by common GPS was downloaded from the Open Street Map.
Technical Paper

Intelligent Traffic Control Method for Emergency Vehicles Prioritization Based on DSRC Transportation System

2018-08-07
2018-01-1644
Emergency Vehicles (EmVs) prioritization is critical to be studied in view of the effectiveness of emergency delivery. Adaptive traffic lights can be employed based on DSRC (Dedicated Short Range Communication) system, as vehicle status and traffic lights information can be delivered to Road Side Unit (RSU). In other research work of manipulating traffic lights, only the EmVs are considered. Therefore there are still risks for non-EmVs due to insufficient time of braking. This paper provides an adaptive traffic light control method which takes into account of EmVs and non-EmVs on all the directions of lanes at the road section. In this control method, three operation modes of traffic light are proposed and the traffic light can be converted among three operation modes: Normal mode, Warning mode and Priority mode.
Technical Paper

Decoupled Control of Vehicular Platoon with Heterogeneous Communication Delay

2018-08-07
2018-01-1645
The problems of traffic congestion, car accident and fuel scarcity can be relieved by forming vehicular platoon with small inter-vehicle spacing, where vehicles transmit their position, velocity and acceleration profiles via wireless communication networks. However, unavoidable and heterogeneous communication delays in reality among vehicles become a challenging problem in the controller design process. This study presents a decoupled control method for a vehicular platoon with heterogeneous communication delays and sampled data, which are closer to the real world. Directed graphs are adopted to describe the information flow of connecting automated vehicles. By designing the state estimator, the influence of communication delays that bring the state errors can be eliminated. The complex coupled platoon control system is decoupled through the eigenvalue decomposition of information topology and the linear transformation of the whole system.
Technical Paper

Modified Car Following and Lane Changing Simulations Model for Autonomous Vehicle on Highway

2018-08-07
2018-01-1647
Being one of the most simple and basic driving scenarios, highway scenario can be one of the first scenarios to achieve autonomous driving. Both car following (CF) and lane changing (LC) are the most basic and frequent maneuver during highway driving tasks, and therefore become two key issues to focus on in recent researches about autonomous vehicle (AV). Different from conventional CF and LC researches that attach much importance to the character, psychology, perception ability, and driving experience of human drivers, more timely and accurate reactions based on fast perception and communication technology as well as the automatic actuator are hypotheses for this research. Moreover, based on these hypotheses, a modified intelligent driver model (MIDM) is proposed for AVs’ following behavior to alleviate the fluctuations caused by lane changing behaviors.
Technical Paper

Swarm Intelligence Based Algorithm for Management of Autonomous Vehicles on Arterials

2018-08-07
2018-01-1646
Connected and autonomous vehicles are different from traditional vehicles. The communication between vehicles (V2V) or between vehicles and infrastructures (V2I) renders it possible to convey traffic information (e.g. signal timing or speed advisory) from signal controllers to vehicles as well as vehicles to vehicles in real time. Taking this advantage, this paper aims to developing an algorithm which enables the interconnected autonomous vehicles running efficiently on arterials. A set of driving rules determining random behavior and swarm behavior of autonomous vehicles is developed based on swarm intelligence theory. Under control of these rules, each autonomous vehicle follows the same rules, which make it select target vehicle from all the optimal individuals in detection zone according to characteristics of itself, then approach to the target by changing lane, following former car, or accelerating.
Technical Paper

Semantic Segmentation with Inverted Residuals and Atrous Convolution

2018-08-07
2018-01-1635
Semantic segmentation has become a fundamental topic in the field of the computer vision, whose goal is to assign each pixel in the image to the corresponding category label. This topic is of broad interest for potential applications in automatic driving. Recently, modern frameworks of semantic segmentation are mostly based on the deep convolutional neural networks. And the general trend focus on increasing the accuracy of the framework, but at the cost of bringing extra parameters and making the network more complicated, which makes the network hard to implement on the vehicle mobile and embedded devices with limited computational resources. In this paper, a novel architecture is developed based on Inverted Residual and Atrous Convolution, in the sense that not only computation cost can be drastically reduced, but also high accuracy can still be maintained.
Technical Paper

Trajectory-Tracking Control for Autonomous Driving Considering Its Stability with ESP

2018-08-07
2018-01-1639
With rapid increase of vehicles on the road, safety concerns have become increasingly prominent. Since the leading cause of many traffic accidents is known to be by human drivers, developing autonomous vehicles is considered to be an effective approach to solve the problems above. Although trajectory tracking plays one of the most important roles on autonomous driving, handling the coupling between trajectory-tracking control and ESP under certain driving scenarios remains to be challenging. This paper focuses on trajectory-tracking control considering the role of ESP. A vehicle model is developed with two degrees of freedom, including vehicle lateral, and yaw motions. Based on the proposed model, the vehicle trajectory is separated into both longitudinal and lateral motion. The coupling effect of the vehicle and ESP is analyzed in the paper. The lateral trajectory-tracking algorithm is developed based on the preview follower theory.
Technical Paper

Analysis of Human Machine Interaction Program in Lane Keeping Assist System Based on Field Test

2018-08-07
2018-01-1632
Lane-keeping assist system (LKA) alerts the driver or intervenes in the driving when the vehicle deviates from the lane. But its effect is highly dependent on the driver’s acceptance. Distance to Lane Crossing (DTLC) and Time to Lane Crossing (TTLC) are two important factors to consider the danger level of the scenario, which are also two references for drivers to make decisions. At present, most of the functional design standards are based on these values, while they often differ for different vehicle movements. This study uses a driving robot to precisely control the test conditions and performs field tests on two advanced autonomous vehicles in National Intelligent Connected Vehicle (Shanghai) Pilot Zone. The test conditions are extended based on various test standards and the LKA performance of vehicles in the pre-experiment.
Technical Paper

An Optimization Approach to Conduction Emission Test of T-BOX

2018-08-07
2018-01-1643
T-BOX can manage the vehicle’s operation data and position data, and provide the following functions, positioning, vehicle status, motor data, BMS working status, charging status and status alarm, which may effectively promote the development of electric vehicle. Meanwhile, it may bring a series of problems, especially the electromagnetic compatibility (EMC) problems. In this paper, for the exceed standard limits problem of a particular T-BOX sample in radiation emission (RE) and conducted emissions(CE) test process, π filter is designed and added to the positive polar and negative polar of power supply based on the analysis of hardware circuit. The conduction emission test results of T-BOX after optimized can meet the requirements of GB/T 18655-2010 Vehicles, boats and internal combustion engines-Radio disturbance characteristics-Limits and methods of measurement for the protection of on-board receiver standard.
Technical Paper

Study on the Controlled Field Test Scenarios of Automated Vehicles

2018-08-07
2018-01-1633
Function and performance test of automated vehicles in the closed field is a necessary way to verify their safety, intelligence and comfort. The design and number of test scenarios will influence if the automated vehicles can be tested and evaluated effectively and fast. Based on the interrelationship among the vehicle, driver’s (or control system) driving strategy and road, we use the permutation and combination method to compare the relative position and movement relations between an automated vehicle (vehicle under test) and the surrounding vehicles to generate a total possible test scenarios group.
Technical Paper

Research on Intelligent Vehicle Index and Evaluation Method

2018-08-07
2018-01-1634
As automobiles are gradually transforming from independent mechanical units to network nodes with intelligent and networked functions, the functions and performance evaluation of intelligent vehicles is facing the new challenges. At present, China has initially classified the level of intelligent vehicles on the basis of SAE, but has not yet formed a scientific, rigorous and comprehensive evaluation system. Therefore, this paper proposes the detailed intelligent evaluation ideas of intelligent vehicles in different levels from 0 to 5 and sets up a "Trinity" evaluation system covering professional evaluation, practical evaluation and market evaluation. Then, with the development progress of intelligent vehicles, we will set up the hierarchical structure of evaluation indicators basing on automated intelligence and connected intelligence.
Technical Paper

Mechanism Analysis and Simulation Study of Automobile Millimeter Wave Radar Noise

2018-08-07
2018-01-1641
The paper analyzes the mechanism of automobile millimeter wave radar noise, this paper does not study radar noise from the angle of signal processing, but from the level of false detection and missed detection, at the same time, the noise mechanism is modeled and verified. Firstly, the purpose and significance of the research of radar vehicle noise are described, and then, we summarize and outline the macro phenomenon and the specific characteristics of the automobile millimeter wave radar noise.
Technical Paper

Experimental Study of Friction Reduction by Reducing Piston Ring Pre-Load

2018-07-09
2018-28-0101
The prime objective of this study is to check the friction reduction by reducing the tangential load of the piston ring. To examine this experimental study has been carried out under motored engine condition from 500 to 4000 engine speed at the step of 500 rpm at different oil temperatures ranging from 40 °C to 120 °C. 15 W40 oil was used for this study. Standard Strip down approach was followed in accessing the Friction. The whole friction measurement was split in crank train and piston group friction and was measured with base and modified piston ring pack. The modified piston ring pack was having 24% less ring tension as compared to base ring pack. The study was carried out using block, crankshaft & Piston of 100 hp, 1.5 litre, 3 cylinder engine with 92 mm stroke and 83 mm bore. In each test ring pack was tested as a part of complete piston assembly.
Technical Paper

Informatics Based Design of Bio-Lubricant with Nano Friction Modifiers and Evaluation of Its Tribological Properties

2018-07-09
2018-28-0100
Statistical and computational intelligence techniques were employed for informatics based design of nano friction modifiers added bio-lubricant. Systematic data were generated through laboratory experiments, using design of experiment, to study the effect of addition of multi-wall carbon nanotubes as friction modifiers in castor oil on frictional properties. The experimental data were used to develop data driven models using statistical techniques, artificial neural network and fuzzy inference systems. The simulation studies which were based on the model predictions were used to design the nano-lubricant with multi-walled carbon nanotubes as the friction modifiers. The optimum combination of nanotube concentration and load, found from the model predictions, were experimentally validated.
Technical Paper

Enhancement of Starter Brush Life for Micro Hybrid (Start/Stop) Applications

2018-07-09
2018-28-0102
In Micro hybrid, start-stop system automatically stop and start the engine to reduce the idling time of engine spend in traffic jams and signals, thereby reducing fuel consumption and emissions. Starter motors used in Micro hybrid (Start/Stop) application has 5~10 times more life cycles than compare to conventional starter because of need to starter in every idling time of engine. There are multiple components in starter motor have sliding contact (mechanical/electrical), rolling contact will inflict the life cycles of starter motor. Brush is one of the major sliding contact elements to inflict the life cycle of starter, brushes are commonly used to conduct current between the stationary and moving part of starter. Brushes are exposed both mechanical and electrical loading conditions. Brush wear is affected by the association of Mechanical wear and electrical wear.
Technical Paper

An Analytical Study of Buckling Behavior of Nanocomposite Beams

2018-07-09
2018-28-0050
The structural members like beams are often subjected a mode of sudden failure due to high compressive load which is characterised as buckling. The buckling behaviour is one of the most important parameters needs to be considered while designing the structural members like beams. The polymer composites are the one of the most emerging materials used in air craft structural applications. This paper studies the buckling behaviour of Carbon Nanotube (CNT) reinforced polymer composite beams by using Classical Laminate Plate Theory (CLPT) approach. The elastic constants obtained for the CNT reinforced polymer composite by applying Mori-Tanaka method are further used to analyse the effect of stacking sequence, CNT Volume fraction in the composite, and CNT radii on the critical buckling loads of an eight layered nanocomposite beam. The Numerical results are also presented and compared for various boundary conditions of beams like clamped-clamped and hinged-hinged.
Technical Paper

Exhaust Emissions Reduction from Neat Biodiesel Operated Diesel Engine Using Catalyst Coated Piston and Antioxidant Additive

2018-07-09
2018-28-0053
The limited work has been done so far using neat biodiesel in the diesel engine since it drastically reduces the brake thermal efficiency and emitting higher amount of oxides of nitrogen. Hence in the present investigation an attempt has been made to use neat biodiesels in DI diesel engine on par with diesel fuel with some alternate methods that have to be incorporated to improve the efficiency and to reduce oxides of nitrogen emission. The biodiesels used for the present investigation are nerium, mahua and calophyllum. The top of the piston is coated with ZrO2 catalyst in order to improve the performance of the engine. Further, 200 mg of L-ascorbic acid antioxidant additive is added to the neat biodiesels to improve the oxidation stability and to reduce the oxides of nitrogen emission. Experiments were conducted in a single cylinder four stroke diesel engine to find the performance and emission characteristics.
Technical Paper

Friction Stir Welding of Aluminum 6082

2018-07-09
2018-28-0051
Friction Stir Welding (FSW) overcomes many of the problems associated with traditional joining techniques. F SW is a solid-state process which produces welds of high quality in difficult-to-weld materials such as aluminum and is fast becoming the process of choice for manufacturing lightweight transport structures such as boats, trains and aero planes. A rotating cylindrical tool with a profiled probe is fed in to a butt joint between two clamped workpieces, until the shoulder, which has a larger diameter than the pin, touches the surface of the workpieces. The probe is slightly shorter than the weld depth required, with the tool shoulder riding at the top of the work surface. In this dissertation two Aluminum 6082 plates were joined with friction stir welding technique. The primary objective of this work is to study the effect of root gap and variation in tool speed on the properties of base metal i.e. AL6082.
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