Alexander Carballo

Dr. Alexander Carballo

orcid

Research Focus & Metrics

Academic Career Length

16Years (2011-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

View All Publications
9 January 2023 in ISPRS Journal of Photogrammetry and Remote Sensing
Verified
Journal Article
Open access
YZYuxiao Zhang
Yuxiao Zhang
ACAlexander Carballo
Alexander Carballo
HYHanting Yang
Hanting Yang
KTKazuya Takeda
Kazuya Takeda

16 July 2020 in IEEE Access
Verified
Journal Article
Open access
JLJacob Lambert
Jacob Lambert
ACAlexander Carballo
Alexander Carballo
ACAbraham Monrroy Cano
Abraham Monrroy Cano
PNPatiphon Narksri
Patiphon Narksri
DWDavid Wong
David Wong
KTKazuya Takeda
Kazuya Takeda
Automated vehicle technology has recently become reliant on 3D LiDAR sensing for perception tasks such as mapping, localization and object detection. This has led to a rapid growth in the LiDAR manufacturing industry with several competing makers releasing new sensors regularly. With this increased variety of LiDARs, each with different properties such as number of laser emitters, resolution, field-of-view, and price tags, a more in-depth comparison of their characteristics and performance is required. This work compares 10 commonly used 3D LiDARs, establishing several metrics to assess their performance. Various outstanding issues with specific LiDARs were qualitatively identified. The accuracy and precision of individual LiDAR beams and accumulated point clouds are evaluated in a controlled environment at distances from 5 to 180 meters. Reflective targets were used to characterize intensity patterns and quantify the impact of surface reflectivity on accuracy and precision. A vehicle and pedestrian mannequin were also used as additional targets of interest. A thorough assessment of these LiDARs is given with their potential applicability for automated driving tasks. The data collected in these experiments and analysis tools are all shared openly.

16 March 2020 in IEEE Transactions on Vehicular Technology
Verified
Journal Article
Open access
KSKyle Sama
Kyle Sama
YMYoichi Morales
Yoichi Morales
HLHailong LIU
Hailong LIU
NANaoki Akai
Naoki Akai
ACAlexander Carballo
Alexander Carballo
KTKazuya Takeda
Kazuya Takeda
This paper introduces a method to extract driving behaviors from a human expert driver which are applied to an autonomous agent to reproduce proactive driving behaviors. Deep learning techniques were used to extract latent features from the collected data. Extracted features were clustered into behaviors and used to create velocity profiles, allowing an autonomous driving agent could drive in a human-like manner. By using proactive driving behaviors, the agent could limit potential sources of discomfort such as jerk and uncomfortable velocities. Additionally, we proposed a method to compare trajectories where not only the geometric similarity is considered, but also velocity, acceleration and jerk. Experimental results in a simulator implemented in ROS show that the autonomous agent built with the driving behaviors was capable of driving similarly to expert human drivers.

5 December 2019 in IEEE Transactions on Intelligent Transportation Systems
Verified
Journal Article
Closed access
CTChenxi Tu
Chenxi Tu
ETEijiro Takeuchi
Eijiro Takeuchi
ACAlexander Carballo
Alexander Carballo
CMChiyomi Miyajima
Chiyomi Miyajima
KTKazuya Takeda
Kazuya Takeda

7 January 2011 in International Journal of Social Robotics
Verified
Journal Article
Closed access
PDF file
ACAlexander Carballo
Alexander Carballo
AOAkihisa Ohya
Akihisa Ohya
SYShin’ichi Yuta
Shin’ichi Yuta

22 March 2023 in IEEE Open Journal of Intelligent Transportation Systems
Verified
Journal Article
Open access
YTYafu Tian
Yafu Tian
ACAlexander Carballo
Alexander Carballo
RLRuifeng Li
Ruifeng Li
KTKazuya Takeda
Kazuya Takeda
Automated identification of the relationships between traffic actors and surrounding objects, in order to describe their behavior and predict their intentions, has become the focus of increasing attention in the field of autonomous driving. Therefore, in this work, we propose a Road Scene Graphs-Graph Convolutional Network (RSG-GCN) as a novel, graph-based model for predicting the topological graph structure of a given traffic scene. The status of the actors and HD map information are integrated as prior knowledge, allowing the edges linking the actor nodes to capture potential semantic relationships, such as “vehicle approaching pedestrian” and “pedestrian waiting at intersection”. To train this model, we created our own RSG dataset, as well as a relational dataset and benchmark derived from nuScenes. Our extensive range of experiments demonstrate that our model can more accurately predict semantic relationships and behavior in a given traffic scene than other popular traffic scene prediction models. In particular, regarding the use of HD map prior knowledge, we found that the resulting increase in accuracy significantly outweighs performance loss caused by the increase in graph size. The downstream applications of RSG include traffic scene retrieval and synthetic traffic scene generation, which are briefly described.