Liang Zhang

• Doctor of Engineering
• academic staff at ETH Zurich

Multi-robot Simultaneous Localization and Mapping (SLAM) systems employing 2D lidar scans are effective for exploration and navigation within GNSS-limited environments. However, scalability concerns arise with larger environments and increased robot numbers, as 2D mapping necessitates substantial processor memory and inter-robot communication bandw...

Aiming at the challenges of unnecessary leap and significant undulations terrains with large steering angles in path planning of multimodal quadruped robots by Rapidly Exploring Random Tree algorithm， a path planning algorithm solution based on discrete sampling is proposed. The path is preprocessed to remove unnecessary leap and a solution set is...

This work addresses a time‐sensitive coverage control problem for multiple non‐holonomic mobile robots. The coverage objective is evaluated by the total arrivial time of robots reaching their dominant clients with the predefined constant but heterogeneous velocities. An extremum‐seeking control framework is proposed, including a numerical optimizer...

This paper considers the $H_{2}$ performance analysis and distributed $H_{2}$ control problems of interconnected large-scale systems (LSSs). According to the developed space construction approach, both novel necessary and sufficient conditions are established to ensure the asymptotic stability and $H_{2}$ performance of the studied LSSs. Next...

In this paper, a model-free off-policy reinforcement learning (RL) algorithm is proposed to address the optimal tracking control (OTC) problem for discrete-time Markov jump linear systems (MJLSs). The tracking reference signal is firstly augmented into discrete-time MJLSs, whereby the original tracking control problem is converted to the optimal co...

This paper tackles the problem of active planning to achieve cooperative localization for multi-robot systems (MRS) under measurement uncertainty in GNSS-limited scenarios. Specifically, we address the issue of accurately predicting the probability of a future connection between two robots equipped with range-based measurement devices. Due to the l...

This work addresses the finite-time enclosing control problem where a set of followers are deployed to encircle and rotate around multiple moving targets with a predefined spacing pattern in finite time. A novel distributed and continuous estimator is firstly proposed to track the geometric center of targets in finite time using only local informat...

This article tackles the problem of active planning to achieve cooperative localization for multirobot systems under measurement uncertainty in GNSS-limited scenarios. Specifically, we address the issue of accurately predicting the probability of a future connection between two robots equipped with range-based measurement devices. Due to the limite...

This manuscript addresses the active positioning service using a multi-robot system (MRS) for providing large-scale coverage and scalability in terms of MRS size. Inspired by the coverage control problems from Wireless Sensor Network (WSN) literature, we propose a gradient-based control method where a \textit{position dilution of precision} (PDOP)...

Satellite pose estimation is an essential task for on-orbit service. After obtaining sequential images of the unknown satellite, its relative pose can be estimated by capturing and matching keypoints in these images. Generally, existing point-based methods will produce numerous keypoints, represented by high-dimensional descriptors. Consequently, t...

This manuscript addresses the active positioning service using a multi-robot system (MRS) for providing large-scale coverage and scalability in terms of MRS size. Inspired by the coverage control problems from Wireless Sensor Network (WSN) literature, we propose a gradient-based control method where a position dilution of precision (PDOP) field is...

This paper presents a method for predicting the probability of future connectivity between mobile robots with range-limited communication. In particular, we focus on its application to active motion planning for cooperative localiza-tion (CL). The probability of connection is modeled by the distribution of quadratic forms in random normal variables...

In this technical note, we address the finite-time consensus problem for a second-order multi-agent system (SOMAS) under event-triggered control strategy. This problem arises from the case where actuators in a SOMAS fail to follow the ideal controller behavior exactly, due to either the failure of an embedded processor to maintain the desired updat...

This paper addresses optimal trajectory generation for active target positioning using a collective localization scheme under a time-varying observation topology. We show that a team of assisting robots using the optimal trajectories can improve the localization accuracy of leader robots whose commands are assigned by high-level tasks. We propose a...

This paper addresses optimal trajectory generation for active target positioning using a collective localization scheme under a time-varying observation topology. We show that a team of assisting robots using the optimal trajectories can improve the localization accuracy of leader robots whose commands are assigned by high-level tasks. We apply the...

In this paper, a surrounding control problem for second-order agent system is investigated. A set of followers composed by the second-order agent networks is applied to surround a team of static leaders into a convex hull spanned by these followers. The problem is considered under a decentralized estimation-and-control framework by using tools from...