Author name cluster

Herbert G. Tanner

Possible papers associated with this exact author name in Arrow. This page groups case-insensitive exact name matches and is not a full identity disambiguation profile.

29 papers

2 author rows

ICRA Conference 2025 Conference Paper

An Equilibrium Analysis of Magnetic Quadrupole Force Field With Applications to Microrobotic Swarm Coordination

Ioannis Faros
Herbert G. Tanner

Controlled microrobots in fluidic environments hold promise for precise drug delivery and cell manipulation, opening new ways for personalized healthcare. However, coordinating magnetic microrobot swarms presents significant challenges due to the complexity of the associated actuation mechanisms. While existing methods to achieve motion differentiation in collections of microrobots rely on design variations among them, the work reported here applies to homogeneous collectives and enables them to be steered as a whole or in fragments, by means of a common externally generated force field. This paper contributes to an emerging set of methods that enable swarm control through manipulation of these force fields. This paper in particular exploits the nature of force field equilibria in a quadrupole workspace configuration as a means of steering the swarm while maintaining its cohesion. The approach also enables splitting the swarm in two subgroups in order to direct each simultaneously to a different location.

ICRA Conference 2025 Conference Paper

ODYSSEE: Oyster Detection Yielded by Sensor Systems on Edge Electronics

Xiaomin Lin 0002
Vivek Mange
Arjun Suresh
Bernhard Neuberger
Aadi Palnitkar
Brendan Campbell
Alan Williams
Kleio Baxevani

Oysters are a vital keystone species in coastal ecosystems, providing significant economic, environmental, and cultural benefits. As the importance of oysters grows, so does the relevance of autonomous systems for their detection and monitoring. However, current monitoring strategies often rely on destructive methods. While manual identification of oysters from video footage is non-destructive, it is time-consuming, requires expert input, and is further complicated by the challenges of the underwater environment. To address these challenges, we propose a novel pipeline using stable diffusion to augment a collected real dataset with photorealistic synthetic data. This method enhances the dataset used to train a YOLOv10-based vision model. The model is then deployed and tested on an edge platform; Aqua2, an Autonomous Underwater Vehicle (AUV), achieving a state-of-the-art 0. 657 mAP@50 for oyster detection.

IROS Conference 2022 Conference Paper

Development and Field Testing of an Optimal Path Following ASV Controller for Marine Surveys

Kleio Baxevani
Grant E. Otto
Herbert G. Tanner
Arthur C. Trembanis

Marine autonomous vehicles deployed to conduct marine geophysical surveys are becoming an increasingly used asset in the commercial, academic, and defense industries. However, the ability to collect high-quality data from applicable sensors is directly related to the robustness of vehicle motion caused by environmental disturbances. In this paper we designed and integrated a new path following controller on an autonomous surface vehicle (ASV) that minimizes the linear and angular accelerations on the sensor's local frame. Simulation and experimental results verify reduction of vehicle motion, improvement in path following, and improvement in preliminary sonar data quality compared to that of the existing proportional-yaw path following controller.

ICRA Conference 2020 Conference Paper

Nonlinear Synchronization Control for Short-Range Mobile Sensors Drifting in Geophysical Flows

Cong Wei 0003
Herbert G. Tanner
M. Ani Hsieh

This paper presents a synchronization controller for mobile sensors that are minimally actuated and can only communicate with each other over a very short range. This work is motivated by ocean monitoring applications where large-scale sensor networks consisting of drifters with minimal actuation capabilities, i. e. , active drifters, are employed. We assume drifters are tasked to monitor regions consisting of gyre flows where their trajectories are periodic. As drifters in neighboring regions move into each other's proximity, it presents an opportunity for data exchange and synchronization to ensure future rendezvous. We present a nonlinear synchronization control strategy to ensure that drifters will periodically rendezvous and maximize the time they are in their rendezvous regions. Numerical simulations and small-scale experiments validate the efficacy of the control strategy and hint at extensions to large-scale mobile sensor networks.

IROS Conference 2020 Conference Paper

Reactive Receding Horizon Planning and Control for Quadrotors with Limited On-Board Sensing

Indrajeet Yadav
Herbert G. Tanner

The paper presents a receding horizon planning strategy for a quadrotor-type mav to navigate through an unknown cluttered environment at high speed. Utilizing a lightweight on-board short-range sensor that generates point-clouds within a narrow Field of View (FOV), the reported approach generates safe and dynamically feasible trajectories within the fov of the sensor, which the mav uses to navigate without relying on any global planner or prior information about the environment. The effectiveness of this planner-controller combination is demonstrated in both indoor and outdoor tests featuring speeds of up to of 3. 5 m/s. With minor adjustments, the local motion planner can be utilized for interception and tracking of a moving target; evidence to this effect are provided in the form of numerical (Gazebo) simulations. Given the absence of any global information about the robot's workspace, the extent to which the local planner can provide convergence guarantees is limited; when complemented by a global planner and/or target tracker, the reported lower-level, sensor-driven reactive motion control strategy completes the autonomous mav navigation stack, enabling navigation in dynamic, uncertain, and partially-known environments with guaranteed convergence to any static or dynamic target.

ICRA Conference 2019 Conference Paper

Composition of Local Potential Functions with Reflection

Adam Stager
Herbert G. Tanner

This paper suggests reflections can be practically useful if they are included in planning for collision capable robot platforms. By modifying a proven strategy for navigation with reflections we maintain global convergence results and reach the goal in less time. An algorithm for identifying reflection surfaces for a given cell decomposition is reported. Baseline and reflected scenarios are compared for two different cell decompositions. Omnipuck, a reflection capable omnidirectional robot meant to store and release impact energy, is used to obtain experimental results and draw conclusions for future work.

ICRA Conference 2015 Conference Paper

A passively sprawling miniature legged robot

Adam Stager
Konstantinos Karydis
Herbert G. Tanner

The paper reports on the design and preliminary experimental testing of a novel 3D-printed miniature legged robot. It is called Passively Sprawling Robot (PSR), and it features a mechanism that achieves passive adjustment of the sprawl angle of the robot's legs. Passive sprawling in this robot exhibits compliance by design, yet it can be controlled indirectly by regulating the yaw rate. Spring-loaded assemblies on the left and right side of the robot function independently, allowing the vehicle to overcome asymmetrical obstacles with improved lateral stability, and withstand falls from moderate heights without sustaining structural damage. The regulation of the sprawling angle by means of varying yaw rates, as well as the improved motion characteristics have been experimentally observed and verified, and open-loop motion accuracy along straight and constant curvature paths was tested on a number of repeated trials.

ICRA Conference 2015 Conference Paper

Active sensor networks for nuclear detection

Jianxin Sun 0002
Herbert G. Tanner
Ioannis Poulakakis

This paper approaches from an optimal control perspective the problem of fixed-time detection of mobile radioactive sources in transit by means of a collection of mobile sensors. Under simplifying assumptions on the geometry of the source, sensors, and surrounding environment, and with knowledge of the source's trajectory, it is shown that the optimal control problem admits an intuitive, analytic closed-form solution. This is facilitated by the availability of analytic expressions for bounds on the probabilities of detection and false alarm during a Neyman-Pearson detection test. The intuition derived from this analytic solution leads to a motion control law that steers suboptimally the sensors to an arbitrarily small neighborhood of the suspected source, while navigating among stationary obstacles in their environment, making a step closer to a practical physical implementation.

ICRA Conference 2015 Conference Paper

Control of stochastic unicycle-type robots

Shridhar K. Shah
Herbert G. Tanner

This paper addresses the problem of optimal control of a unicycle-type robot perturbed with stochastic noise in an environment with sparsely populated obstacles. The objective is that the robot pose converges to a neighborhood of a desired position and orientation. A feedback control law is constructed such that it is compatible with the differential constraints of the unicycle. The construction is based on numerical solution of the Hamilton-Jacobi-Bellman (HJB) partial differential equation (PDE) associated with a stochastic optimal control problem. The control law is optimal in terms of control effort and comes with probabilistic guarantees of convergence to the goal set.

EAAI Journal 2015 Journal Article

Symbolic planning and control using game theory and grammatical inference

Jie Fu
Herbert G. Tanner
Jeffrey N. Heinz
Konstantinos Karydis
Jane Chandlee
Cesar Koirala

A system can accomplish an objective specified in temporal logic while interacting with an unknown, dynamic but rule-governed environment, by employing grammatical inference and adapting its plan of action on-line. The purposeful interaction of the system with its unknown environment can be described by a deterministic two-player zero-sum game. Using special new product operations, the whole game can be expressed with a factored, modular representation. This representation not only offers computational benefits but also isolates the unknown behavior of the dynamic environment in a particular subsystem, which then becomes the target of learning. As the fidelity of the identified environment model increases, the strategy synthesized based on the learned hypothesis converges in finite time to the one that satisfies the task specification.

IROS Conference 2014 Conference Paper

Planning with the STAR(s)

Konstantinos Karydis
David Zarrouk
Ioannis Poulakakis
Ronald S. Fearing
Herbert G. Tanner

We present our findings on the first application of motion planning methodologies to the recently introduced Sprawl Tuned Autonomous Robot (STAR). The reported results provide a first glimpse on the capabilities of this novel, 3D-printed robot in performing autonomously non-trivial motion planning tasks in environments populated with obstacles. We employ methods from sampling-based motion planning under nonholonomic constraints, and implement in open loop the generated path on the physical robot for various environments of increasing complexity.

ICRA Conference 2013 Conference Paper

Probabilistic validation of a stochastic kinematic model for an eight-legged robot

Konstantinos Karydis
Ioannis Poulakakis
Herbert G. Tanner

The paper suggests a new method for statistically validating, and selecting the parameters of a model for a miniature eight-legged robot. It is based on a novel adaptation of concepts and techniques originally developed in the context of robust control design using randomized algorithms. The proposed approach is data driven and offers probabilistic guarantees of model fidelity and descriptive capacity, checking models against experimental data. In principle, this method applies to a large class of physical processes, the available models of which may be in a variety of forms including sets of differential equations.

IROS Conference 2012 Conference Paper

A switching kinematic model for an octapedal robot

Konstantinos Karydis
Ioannis Poulakakis
Herbert G. Tanner

We propose a new model to describe the horizontal motion of an eight-legged bio-inspired miniature robot. The model does not include compliance, and can capture the kinematics of the observed locomotion behavior that corresponds to an alternating tetrapod gait. We exploit symmetries and synergies to reduce the eight-legged robot to a mechanism that is composed by two switching four-bar linkages, each representing the collective effect of a tetrapod in contact with the ground. Notwithstanding its apparent simplicity, the resulting model reproduces on average the motion of the robot. In addition, by properly tuning a family of physically-relevant parameters - including touchdown and sweep angles - different motion primitives corresponding to circular and forward motions can be realized. This model represents a first step toward developing reduced-order kinematic representations of legged robots that can be used for motion planning and feedback control purposes.

ICRA Conference 2012 Conference Paper

Model predictive navigation for position and orientation control of nonholonomic vehicles

Konstantinos Karydis
Luis Valbuena
Herbert G. Tanner

In this paper we consider a nonholonomic system in the form of a unicycle and steer it to the origin so that both position and orientation converge to zero while avoiding obstacles. We introduce an artificial reference field, propose a discontinuous control policy consisting of a receding horizon strategy and implement the resulting field-based controller in a way that theoretically guarantees for collision avoidance; convergence of both position and orientation can also be established. The analysis integrates an invariance principle for differential inclusions with model predictive control. In this approach there is no need for the terminal cost in receding horizon optimization to be a positive definite function.

ICRA Conference 2012 Conference Paper

Stochastic receding horizon control for robots with probabilistic state constraints

Shridhar K. Shah
Chetan D. Pahlajani
Nicholaus A. Lacock
Herbert G. Tanner

This paper presents a receding horizon control design for a robot subject to stochastic uncertainty, moving in a constrained environment. Instead of minimizing the expectation of a cost functional while ensuring satisfaction of probabilistic state constraints, we propose a two-stage solution where the path that minimizes the cost functional is planned deterministically, and a local stochastic optimal controller with exit constraints ensures satisfaction of probabilistic state constraints while following the planned path. This control design strategy ensures boundedness of errors around the reference path and collision-free convergence to the goal with probability one under the assumption of unbounded inputs. We show that explicit expressions for the control law are possible for certain cases. We provide simulation results for a point robot moving in a constrained two-dimensional environment under Brownian noise. The method can be extended to systems with bounded inputs, if a small nonzero probability of failure can be accepted.

IROS Conference 2011 Conference Paper

Probability of success in stochastic robot navigation with state feedback

Shridhar K. Shah
Chetan D. Pahlajani
Herbert G. Tanner

The analysis in this paper applies to robots with dynamics described by a stochastic differential equation, which need to navigate in constrained environments. The approach offers a method to calculate the probability that a feedback control policy designed for the drift component of the dynamics, will succeed in allowing the robot to avoid collisions and converge to its navigation goal in the presence of stochastic (white) noise. The problem is formulated as an exit problem and known techniques in the field of stochastic processes are brought to bear to determine the probabilities that the stochastic process describing the motion of the robot will ¿exit¿ the workspace through a particular part of the boundary. We motivate the use of this analysis using a controller constructed using negative gradient of a navigation function and give the analytic solution for the case of a constrained but obstacle-free workspace.

ICRA Conference 2010 Conference Paper

Dipole-like fields for stabilization of systems with Pfaffian constraints

Dimitra Panagou
Herbert G. Tanner
Kostas J. Kyriakopoulos

This paper introduces a framework that guides the design of stabilizing feedback control laws for systems with Pfaffian constraints. A new class of N-dimensional vector fields, the dipole-like vector fields is proposed, inspired by the form of the flow lines of the electric point dipole. A general connection between the dipole-like field and the Pfaffian constraints of catastatic nonholonomic systems is exploited, to establish systematic guidelines on the design of stabilizing control laws. The methodology is applied to the stabilization of the unicycle and of the nonholonomic double integrator. Based on these guidelines, switching control laws are constructed. The efficacy of the methodology is demonstrated through simulation results.

ICRA Conference 2009 Conference Paper

Randomized model predictive control for robot navigation

Jorge L. Piovesan
Herbert G. Tanner

The paper suggests a new approach to navigation of mobile robots, based on nonlinear model predictive control and using a navigation function as a control Lyapunov function. In this approach, the nonlinear optimal control problem is treated using randomized algorithms. The advantage of the proposed combination of navigation functions for robot motion planning with randomized algorithms within an MPC framework, is that the control design offers stability by design, is platform independent, and allows the designer to trade-off performance for (computation) speed, according to the application requirements.

ICRA Conference 2007 Conference Paper

Switched UAV-UGV Cooperation Scheme for Target Detection

Herbert G. Tanner

We develop a switched cooperative control scheme, to coordinate groups of ground and aerial vehicles for the purpose of locating a moving target in a given area. We do so by stabilizing the ground group into a guarding formation using a navigation function, and then steering the aerial group along a trajectory that uniformly scans the enclosed regions. The novelty of the approach lays in combining decentralized flocking algorithms with navigation functions for obstacle avoidance, convergence to designated position, and direction control.

ICRA Conference 2005 Conference Paper

Towards Decentralization of Multi-robot Navigation Functions

Herbert G. Tanner
Amit Kumar

We present a navigation function through which a group of mobile agents can be coordinated to achieve a particular formation, both in terms of shape and orientation, while avoiding collisions between themselves and with obstacles in the environment. Convergence is global and complete, subject to the constraints of the navigation function methodology. Algebraic graph theoretic properties associated with the interconnection graph are shown to affect the shape of the navigation function. The approach is centralized but the potential function is constructed in a way that facilitates complete decentralization. The strategy presented will also serve as a point of reference and comparison in quantifying the cost of decentralization in terms of performance.

ICRA Conference 2004 Conference Paper

Flocking with Obstacle Avoidance in Switching Networks of Interconnected Vehicles

Herbert G. Tanner

The paper introduces a set of nonsmooth control laws that enable a group of vehicles to synchronize their velocity vectors and move as a flock while avoiding collisions with each other and with static obstacles in their environment. In addition, all vehicles converge to a common destination point, accomplishing a group mission. The proposed control law can steer each vehicle based on local information that can be obtained from within a spherical neighborhood around it. While only the nearest neighbors and obstacles affect a vehicle's motion, as the vehicles move the neighborhoods change discontinuously. The induced discontinuities in the control law of each vehicle do not affect the stability properties of the group collision free motion and connectivity requirements on the interconnection network can be relaxed due to the common objective.

IROS Conference 2003 Conference Paper

Closed loop navigation for mobile agents in dynamic environments

Savvas G. Loizou
Herbert G. Tanner
Vijay Kumar 0001
Kostas J. Kyriakopoulos

We apply a novel motion planning and control methodology, which is based on a non-smooth navigation function, to a point mobile robot moving amongst moving obstacles. The chattering introduced by the discontinuous potential field is suppressed using non-smooth backstepping. The combined controller guarantees global asymptotic convergence and collision avoidance. This controller is particularly suitable for real time implementation on systems with limited computational resources. The effectiveness of the proposed scheme is verified through computer simulations.

IROS Conference 2003 Conference Paper

ISS properties of nonholonomic mobile robots

Herbert G. Tanner

The paper presents the first result on ISS properties of dynamic unicycle models describing nonholonomic mobile robots. It is known that ISS is related to smooth stabilizability, however this relation cannot exclude the possibility of non smoothly stabilizable systems enjoying ISS properties. In fact, it is shown that in a certain topology that seems to suit the nonholonomic nature of the mobile robot, and by applying a particular control law, the closed loop system can be rendered locally ISS. Apart from any possible theoretical ramifications, this result encourages an ISS-based stability analysis of groups of mobile robots.

ICRA Conference 2002 Conference Paper

Discontinuous Backstepping for Stabilization of Nonholonomic Mobile Robots

Herbert G. Tanner
Kostas J. Kyriakopoulos

Presents a method of performing integrator backstepping in systems that are discontinuous, either due to their inherent structure or because of the applied control input. The proposed technique is applied to the stabilization problem of the dynamic system of a nonholonomic mobile robot. Simulation studies indicate that the methodology can also help alleviate the problem of chattering that is commonly associated with discontinuous nonholonomic controllers.

ICRA Conference 2002 Conference Paper

The Effect of Feedback and Feedforward on Formation ISS

Herbert G. Tanner
Vijay Kumar 0001
George J. Pappas

A new type of stability of leader follower formations is defined, based on input-to-state stability (ISS) properties of cascade interconnections. Formation ISS links leader input to internal state of the formation and characterizes the way this input affects performance. The effect of feedforward and feedback inter-agent communication is then investigated in this framework and it is indicated how the structure of interconnections and the amount of available information can affect stability performance.

IROS Conference 2001 Conference Paper

Nonholonomic stabilization with collision avoidance for mobile robots

Herbert G. Tanner
Savvas G. Loizou
Kostas J. Kyriakopoulos

This paper presents a motion planner and nonholonomic controller for a mobile robot, with global collision avoidance and convergence properties. An appropriately designed (dipolar) potential field is combined with discontinuous state feedback. A new class of Lyapunov functions is introduced and used for nonholonomic navigation. The obstacle avoidance and global asymptotic stability properties are verified through simulations.

ICRA Conference 2001 Conference Paper

Position and Force Control by Reaction Compensation

Herbert G. Tanner
Kostas J. Kyriakopoulos

The paper presents a new position/force controller, based on the philosophy of the parallel approach. The controller exploits the reaction compensation action of the inverse dynamics position controller and achieves superior transient performance. It incorporates a velocity dependent damping term. Stability is established and conditions for the control parameters are derived. Performance of the proposed controller is verified through computer simulations.

ICRA Conference 2000 Conference Paper

Nonholonomic Motion Planning for Mobile Manipulators

Herbert G. Tanner
Kostas J. Kyriakopoulos

A nonholonomic motion planner for mobile manipulators moving in cluttered environments is presented. The approach is based on a discontinuous feedback law under the influence of a special potential field. Convergence is shown via Lyapunov's direct method. Utilizing redundancy, the methodology allows the system to perform secondary, configuration dependent, objectives such as singularity avoidance. It introduces an efficient feedback scheme for real time navigation of nonholonomic systems.

ICRA Conference 1999 Conference Paper

Analysis of Deformable Object Handling

Herbert G. Tanner
Kostas J. Kyriakopoulos

A manipulated deformable object is viewed as an underactuated mechanical system. In this context controllability issues are discussed and results on the nature of the constraints and the controllability properties of an important class of deformable objects being modeled with finite elements are stated. For this class of deformable objects the results permit to circumvent the usual procedure of calculating Lie brackets to establish a base for the associated Lie algebra, and answers the question of determining the kind of constraints imposed on the system in a straightforward algebraic way. Inequality constraints associated to material strength limitations are also included.