arXiv subjects

Baoming Wang

Publications and source records attributed to Baoming Wang.

4 recordsLinked to original sources

arXiv2024

Automated Lane Change Behavior Prediction and Environmental Perception Based on SLAM Technology

In addition to environmental perception sensors such as cameras, radars, etc. in the automatic driving system, the external environment of the vehicle is perceived, in fact, there is also a perception sensor that has been silently dedicated in the system, that is, the positioning module. This paper explores the application of SLAM (Simultaneous Localization and Mapping) technology in the context of automatic lane change behavior prediction and environment perception for autonomous vehicles. It discusses the limitations of traditional positioning methods, introduces SLAM technology, and compares LIDAR SLAM with visual SLAM. Real-world examples from companies like Tesla, Waymo, and Mobileye showcase the integration of AI-driven technologies, sensor fusion, and SLAM in autonomous driving systems. The paper then delves into the specifics of SLAM algorithms, sensor technologies, and the importance of automatic lane changes in driving safety and efficiency. It highlights Tesla's recent update to its Autopilot system, which incorporates automatic lane change functionality using SLAM technology. The paper concludes by emphasizing the crucial role of SLAM in enabling accurate environment perception, positioning, and decision-making for autonomous vehicles, ultimately enhancing safety and driving experience.

cs.RO↗

arXiv2023

Salt-assisted vapor-liquid-solid growth of one-dimensional van der Waals materials

We have combined the benefits of two catalytic growth phenomena to form nanostructures of transition metal trichalcogenides (TMTs), materials that are challenging to grow in a nanostructured form by conventional techniques, as required to exploit their exotic physics. Our growth strategy combines the benefits of vapor-liquid-solid (VLS) growth in controlling dimension and growth location, and salt-assisted growth for fast growth at moderate temperatures. This salt-assisted VLS growth is enabled through use of a catalyst that includes Au and an alkali metal halide. We demonstrate high yields of NbS3 1D nanostructures with sub-ten nanometer diameter, tens of micrometers length, and distinct 1D morphologies consisting of nanowires and nanoribbons with [010] and [100] growth orientations, respectively. We present strategies to control the growth location, size, and morphology. We extend the growth method to synthesize other TMTs, NbSe3 and TiS3, as nanowires. Finally, we discuss the growth mechanism based on the relationships we measure between the materials characteristics (growth orientation, morphology and dimensions) and the growth conditions (catalyst volume and growth time). Our study introduces opportunities to expand the library of emerging 1D vdW materials and their heterostructures with controllable nanoscale dimensions.

cond-mat.mtrl-sci↗

arXiv2022

Kinetic control for planar oxidation of MoS$_2$

Layered transition metal dichalcogenide (TMD) semiconductors oxidize readily in a variety of conditions, and a thorough understanding of this oxide formation is required for the advancement of TMD-based microelectronics. Here, we combine scanning transmission electron microscopy (STEM) with spectroscopic ellipsometry (SE) to investigate oxide formation at the atomic scale of the most widely-studied TMD, MoS$_2$. We find that aggressive thermal oxidation results in $α$-phase plate-like crystalline MoO$_3$ with sharp interfaces, voids, and a textured alignment with the underlying MoS$_2$. Experiments with remote substrates and patterned MoS$_2$ prove that thermal oxidation proceeds via vapor-phase mass transport and redeposition - a challenge to forming thin, conformal planar oxide films. We accelerate the kinetics of oxidation relative to the kinetics of mass transport using a non-thermal oxygen plasma process, to form a smooth and conformal amorphous oxide. The resulting amorphous MoO$_3$ films can be grown several nanometers thick, and we calibrate the oxidation rate for varying plasma processing conditions. Our results illustrate how TMD semiconductor oxidation differs significantly from oxidation of legacy semiconductors, most notably silicon, and provide quantitative guidance for managing both the atomic scale structure and thin film morphology of oxides in the design and processing of MoS$_2$ semiconductor devices.

physics.app-ph↗

arXiv2022

Mechanisms of quasi-van der Waals epitaxy of 3D metallic nanoislands on suspended 2D materials

Understanding structure at the interface between two-dimensional (2D) materials and 3D metals is crucial for designing novel 2D/3D heterostructures and improving the performance of many 2D material devices. Here, we quantify and discuss the 2D/3D interface structure and the 3D morphology in several materials systems. We first deposit facetted Au nanoislands on graphene and transition metal dichalcogenides, using measurements of the equilibrium island shape to determine values for the 2D/Au interface energies and examining the role of surface reconstructions, chemical identity, and defects on the grown structures. We then deposit the technologically relevant metals Ti and Nb under conditions where kinetic rather than thermodynamic factors govern growth. We describe a transition from dendritic to facetted islands as a function of growth temperature and discuss the factors determining island shape in these materials systems. Finally, we show that suspended 2D materials enable the fabrication of a novel type of 3D/2D/3D heterostructure and discuss the growth mechanism. We suggest that emerging nanodevices will utilize such versatile fabrication of 2D/3D heterostructures with well-characterized interfaces and morphologies.

cond-mat.mtrl-sci↗