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Technical Paper

A Semantic Slam System Based on Visual-Inertial Information and around View Images for Underground Parking Lot

2021-04-06
2021-01-0078
As one of the most challenging driving tasks, parking is a common but particularly troublesome problem in large cities. Recently, an excellent solution-automated valet parking (AVP) has become a hot research topic, which allows the driver to leave the vehicle in a drop-off area, while the vehicle driving into the parking slot by itself. For AVP, the precise localization is an indispensable module. However, the global positioning system (GPS) cannot be used in the underground parking lot and the localization method based on lidar is too expensive. In response to solve this problem, we propose a simultaneous localization and mapping system with the semantic information of parking slots (PS-SLAM), which is based on visual-inertial and around view images. First, the calibration of multi-sensors is conducted to obtain their intrinsic and extrinsic parameters. In this way, the around view image and transformation matrices between sensors can be acquired.
Technical Paper

An Augmented around View Monitor System Fusing Depth and Image Information during the Reversing Process

2020-04-14
2020-01-0095
The around view monitor (AVM) system for vehicles usually suffers from the distortion of surrounding objects caused by incomplete rectification and stitching, which seriously affects the driver's judgment of the surrounding environment during the reversing process. In response to solve this problem, an augmented around view monitor (AAVM) system fusing image and depth information is proposed, which highlights the point clouds of persons or vehicles at the rear of the vehicle. First, an around view image is generated from four fisheye cameras. Then, the calibration of multi TOF cameras is conducted to improve their accuracy of depth estimation and obtain extrinsic camera positions. Next, the 2D-driven object point cloud detection method is proposed to localize and segment object point clouds like vehicles or persons.
Technical Paper

Attitude Stability Control and Visualization Simulation for Vertical Take-Off and Landing (VTOL) Fixed-Wing Aircraft

2023-12-31
2023-01-7102
Direct debugging of a vertical takeoff and landing (VTOL) fixed-wing aircraft’s control system can easily result in risk and personnel damage. It is effectively to employ simulation and numerical methods to validate control performance. In this paper, the attitude stabilization controller for VTOL fixed-wing aircraft is designed, and the controller performance is verified by MATLAB and visual simulation software, which significantly increases designed efficiency and safety of the controller. In detail, we first develop the VTOL fixed-wing aircraft’s six degrees of freedom kinematics and dynamics models using Simulink module, and the cascade PID control technique is applied to the VTOL aircraft’s attitude stabilization control. Then the visual simulation program records the flight data and displays the flight course and condition, which can validate the designed controller performance effectively.
Technical Paper

Calibration and Stitching Methods of Around View Monitor System of Articulated Multi-Carriage Road Vehicle for Intelligent Transportation

2019-04-02
2019-01-0873
The around view monitor (AVM) system for the long-body road vehicle with multiple articulated carriages usually suffers from the incomplete distortion rectification of fisheye cameras and the irregular image stitching area caused by the change of relative position of the cameras on different carriages while the vehicle is in motion. In response to these problems, a set of calibration and stitching methods of AVM are proposed. First, a radial-distortion-based rectification method is adopted and improved. This method establishes two lost functions and solves the model parameters with the two-step optimization method. Then, AVM system calibration is conducted, and the perspective transformation matrix is calculated. After that, a static basic look-up table is generated based on the distortion rectification model and perspective transformation matrix.
Technical Paper

Deep Integrated Development of On-Board Charger and DC/DC on Component Level for New Energy Vehicles

2022-03-29
2022-01-0167
The on-board charger and DC/DC undertake the power conversion function between AC charging of new energy vehicles and low-voltage power supply of the vehicle, which are indispensable parts of the vehicle system. With the rapid development of electric vehicle industry, the current automotive industry has more and more stringent requirements on power system. Lightweight and high power density are more and more important for OEMs. With the increasing popularity of electric vehicles, how to reduce the cost has become one of the most important indicators for OEMs. In the traditional on-board power supply, the on-board charger and DC/DC are mostly combined as independent parts in the vehicle system. In order to meet the integration requirements of OEMs, the on-board charger and DC/DC are even put on a PCB board or only in a shell, so as to achieve the so-called "integration" requirements.
Technical Paper

Detection of Gasoline Vehicles with Gross PM Emissions

2007-04-16
2007-01-1113
Light duty gasoline vehicles (LDGV) are estimated to contribute 40% of the total on-road mobile source tailpipe emissions of particulate matter (PM) in California. While considerable efforts have been made to reduce toxic diesel PM emissions going into the future, less emphasis has been placed on PM from LDGVs. The goals of this work were to characterize a small fleet of visibly smoking and high PM emitting LDGVs, to explore the potential PM-reduction benefits of Smog Check and of repairs, and to examine remote sensing devices (RSD) as a potential method for identifying high PM emitters in the in-use fleet. For this study, we recruited a fleet of eight vehicles covering a spectrum of PM emission levels. PM and criteria pollutant emissions were quantified on a dynamometer and CVS dilution tunnel system over the Unified Cycle using standard methods and real time PM instruments.
Technical Paper

Functional Safety Development of Bi-Directional On-Board Charger for New Energy Vehicles

2020-04-14
2020-01-0608
BOBC (Bi-directional on-board charger) is a power conversion system component for AC charging and discharging of new energy vehicles. It has two working modes: AC charging mode and AC discharge mode. In the two working modes, the BOBC belongs to both the controller and the actuator. In some extreme cases such as communication and control failure of the AC charging mode, new energy vehicles have the risk of high-voltage battery overcharging and overheating, which will lead to high-voltage battery fire or even explosion. In the AC discharge mode, it involves the actual operation of the users on electricity, and the risk of short circuit and open circuit may happen in the process, which endangers the safety of the users. Based on the risks brought by the two working modes, it should pay more attention to the safety of the BOBC.
Technical Paper

Investigation on Cold Starting and Warming up of Gasoline Engines with EFI

2007-10-30
2007-32-0070
The cold starting and cold-state running cycle (i.e. engine warming up) of gasoline engines are the key points of exhaust emissions formation of modern engines, and also one of the very important targets for the increasingly stringent emissions regulations. The combustion stability in gasoline engine cold starting and warming up will impact the formation of its exhaust emissions. This paper introduces the improvement in cold starting and warming up combustion process for the motorcycle gasoline engine by high-energy, dual-spark plug based rapid burning system. Test results showed that the high-energy, dual-spark plug based rapid burning system was very helpful to rapid ignition under the engine cold starting condition. Meanwhile, because of increasing the burning velocity of the engine mixture, this solution can realize the larger ignition retard and stable combustion process under the engine warming-up condition.
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