Ben M Chen

Ben M Chen
The Chinese University of Hong Kong | CUHK · Department of Mechanical and Automation Engineering

PhD

About

566
Publications
62,843
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11,266
Citations

Publications

Publications (566)
Article
In this paper, we consider the semi‐global leader–following output consensus of heterogeneous multi‐agent linear systems over a directed communication graph with both the leader agent and the follower agents subject to input saturation. Via the low gain feedback design technique, both the state feedback and output feedback consensus protocols are c...
Article
Full-text available
We study in this paper a semi-global leader-following output consensus problem for multiple heterogeneous linear systems in the presence of actuator position and rate saturation over a directed topology. For each follower, via the low gain feedback design technique and output regulation theory, both a state feedback consensus protocol and an output...
Article
Full-text available
In this paper, we present a trajectory generation method of a quadrotor, based on the optimal smoothing B-spline, for tracking a moving target with consideration of relative tracking pattern or limited field of view of the onboard sensor in cluttered environments. Compared to existing methods, safe flying zone, vehicle physical limits, and smoothne...
Article
Full-text available
This paper addresses the challenging problem of chasing an escaping target using a quadrotor in cluttered environments. To tackle these challenges, we propose a guided time-optimal model predictive control (GTO-MPC) based practical framework to generate chasing trajectories for the quadrotor. A jerk limited approach is first adopted to find a time-...
Article
In this paper, we investigate a formation control problem of multi-agent systems (specifically a group of unmanned aerial vehicles) based on a semi-global leader-following consensus approach with both the leader and the followers subject to input saturation. Utilizing the low gain feedback design technique, a distributed static control protocol and...
Article
As the development of mobile robots matures, there is an increasing amount of interest in expanding the functionality of such robots through developing multimodal locomotion. As compared to land–water or land–air hybrids, the design of air–water vehicles is much less straightforward due to the fact that both mediums are three-dimensional fluid spac...
Article
Motivated by the promising applications of multiple Euler-Lagrange (EL) systems, we study, in this article, the formation-containment (FC) control problem for multiple EL systems of leaders with bounded unknown control inputs and with communication among each other over directed topologies, which can cooperatively generate safe trajectories to avoi...
Article
Unmanned aerial systems provide many applications with the ability to perform flying tasks autonomously, and hence have received significant research and commercial attention in the past decade. One of the most popular unmanned aerial platforms for such tasks is the small-scale rotorcraft with multiple rotors, commonly known as multicopters. In ord...
Article
Autonomous underwater vehicles (AUVs) highly depend on the quality of captured underwater images to perform a variety of tasks. However, compared with everyday images taken in air, underwater images are hazy, with color shift, and in relatively low quality, posing significant challenges to available mature vision algorithms to achieve expected perf...
Article
In this article, we present a comprehensive design and implementation for a micro aerial vehicle (MAV) that is able to perform 3-D autonomous navigation and obstacle avoidance in cluttered and realistic unknown environments without the aid of global positioning system and other external sensors or markers. To achieve these autonomous missions, modu...
Conference Paper
Full-text available
A salient object detection approach is proposed in this paper, tailored to the aerial images collected by Unmanned Aerial Vehicles (UAVs). In particular, the aerial images are classified. The selected image is segmented using superpixel-s, and then a weak saliency map is constructed based on image priors. Positive and negative samples are selected...
Preprint
Full-text available
With the increasing need for micro aerial vehicles (MAVs) to work in GPS-denied environments, vision technique has been extensively explored to realize robust flight control. In this paper, we propose to employ Google map, which could be outdated due to the lag of updating, as reference to realize robust navigation for MAVs equipped with a downward...
Article
Although there have been several proposed methods and existing prototypes demonstrating the functionality of aerial-aquatic vehicles, most are fundamentally aerial vehicles with varying degrees of operability when submerged. We aim to improve the balance of aerial-aquatic functionality by proposing a morphable vehicle structure where the rotors can...
Preprint
Color correction for underwater images has received increasing interests, due to its critical role in facilitating available mature vision algorithms for underwater scenarios. Inspired by the stunning success of deep convolutional neural networks (DCNNs) techniques in many vision tasks, especially the strength in extracting features in multiple sca...
Article
In this paper, we study the formation control of multiple Euler-Lagrange systems with nonautonomous leaders, which means the leaders have bounded unknown inputs. Firstly, adaptive distributed observers to the leaders’ input bounds and states are designed for every follower. In addition, a discontinuous function in the adaptive distributed observer...
Article
Color correction for underwater images has received increasing interest, due to its critical role in facilitating available mature vision algorithms for underwater scenarios. Inspired by the stunning success of deep convolutional neural network (DCNN) techniques in many vision tasks, especially the strength in extracting features in multiple scales...
Article
Flocking control has been studied extensively along with the wide applications of multivehicle systems. In this article, the distributed flocking control strategy is studied for a network of autonomous vehicles with limited communication range. The main difference from the existing methods lies in that collision avoidance is considered a necessary...
Article
Motion primitives are frequently used to find valid local trajectories for mobile robots, especially in cases where fast replanning is required but the onboard computational power is limited. In this paper, we present a practical framework to construct motion primitives from boundary state constraints and further use them for online planning. The p...
Article
Micro Aerial Vehicles (MAVs) have great potentials to be applied for indoor search and rescue missions. In this paper, we propose a modular lightweight design of an autonomous MAV with integrated hardware and software. The MAV is equipped with the 2D laser scanner, camera, mission computer and flight controller, running all the computation onboard...
Article
Integrator based model is used to describe a wide range of systems in robotics. In this paper, we present an axis-coupled trajectory generation algorithm for chains of integrators with an arbitrary order. Special notice has been given to problems with pre-existing nominal plans, which are common in robotic applications. It also handles various type...
Article
Many aerial applications require unmanned aerial systems operate in safe zones because of the presence of obstacles or security regulations. It is a non-trivial task to generate a smooth trajectory satisfying both dynamic constraints and motion limits of the unmanned vehicles while being inside the safe zones. Then the task becomes even more challe...
Article
Full-text available
In this paper, we present a 3D rotating laser-based navigation framework for micro aerial vehicles (MAVs) to fly autonomously in dynamic environments. It consists of a 6-degree of freedom (DoF) localization module and a 3D dynamic mapping module. A self-designed rotating laser scanner generates dense point clouds in which 3D features are extracted...
Preprint
Full-text available
Driven by applications like Micro Aerial Vehicles (MAVs), driver-less cars, etc, localization solution has become an active research topic in the past decade. In recent years, Ultra Wideband (UWB) emerged as a promising technology because of its impressive performance in both indoor and outdoor positioning. But algorithms relying only on UWB sensor...
Article
The idea of cooperative carrying using a team of unmanned aerial vehicles (UAVs) has been viewed as a widely applicable and deployable use of unmanned multi-agent systems, yet there are very few working systems that can successfully perform such tasks due to the complexities involved. One of the primary challenges is the limited control authority o...
Conference Paper
Full-text available
This paper presents SO-Net, a permutation invariant architecture for deep learning with orderless point clouds. The SO-Net models the spatial distribution of point cloud by building a Self-Organizing Map (SOM). Based on the SOM, SO-Net performs hierarchical feature extraction on individual points and SOM nodes, and ultimately represents the input p...
Article
This paper proposes a systematic modeling approach of rotor-driving dynamics for small unmanned aerial vehicles (UAVs) based on system identification and first principle-based methods. Both steady state response analyses and frequency-domain identifications are conducted for the rotor, and Comprehensive Identification from Frequency Responses (CIFE...
Article
Hybrid UAV is an attractive design concept in the last decade for its superiority in combining vertical take-off and landing (VTOL) and cruise flight capabilities. In this work, we present a systematic design methodology from bottom up for an innovative tail-sitter UAV platform, named J-Lion. Implementation details are included with all design consi...
Article
This paper develops a method of calculating the three-dimensional coordinates of a target with image information taken from an unmanned aerial vehicle. Unlike the usual approaches to target geolocation that rely heavily on georeferenced terrain data base or accurate attitude sensors, the contribution of the proposed method is to offset the constrai...
Article
Advancement in the development of automation in aerial robotics has created endless applications today by utilizing autonomous drones, or in other words, unmanned aerial vehicles (UAVs). Motivated by the idea of the entertainment robots, in this paper, we present a robust and safe multi-UAV formation system for the purpose of entertainment in the f...
Article
Majority of today's fixed-pitch, electric-power quadrotors have short flight endurance ($<$ 1 hour) which greatly limits their applications. This paper presents a design methodology for the construction of a long-endurance quadrotor using variable-pitch rotors and a gasoline-engine. The methodology consists of three aspects. Firstly, the rotor blad...
Article
An online rectangle based scheduling algorithm (RSA) is developed to improve autonomy of multiple unmanned aerial vehicles (UAVs) to search a field of forest together. The purposes of RSA are to online decide the number of the UAVs to be assigned and to schedule the path for the assigned UAVs to search the missed areas resulted from the previous se...