Publications de Alexander Bahr

Vertex: A New Distributed Underwater Robotic Platform for Environmental Monitoring

Alcherio Martinoli, Alexander Bahr, Felix Stephan Schill

We present a new Autonomous Underwater Vehicle (AUV) system for cooperative environmental sensing. The AUV was specifically developed as a platform for distributed, cooperative sensing in lakes and coastal areas. In this paper we describe the prerequisite ...

SPRINGER INTERNATIONAL PUBLISHING AG2019

Easily Deployable Underwater Acoustic Navigation System for Multi-Vehicle Environmental Sampling Applications

Alcherio Martinoli, Alexander Bahr, Felix Stephan Schill, Anwar Ahmad Quraishi

Water as a medium poses a number of challenges for robots, limiting the progress of research in underwater robotics vis-a-vis ground or aerial robotics. The primary challenges are satellite based positioning and radio communication being unusable due to hi ...

IEEE2019

A Flexible Navigation Support System for a Team of Underwater Robots

Alcherio Martinoli, Alexander Bahr, Felix Stephan Schill, Anwar Ahmad Quraishi

2019

Autonomous Feature Tracing and Adaptive Sampling in Real-World Underwater Environments

Alcherio Martinoli, Alexander Bahr, Felix Stephan Schill, Anwar Ahmad Quraishi

Applications of robots for gathering data in underwater environments has been limited due to the challenges posed by the medium. We have developed a miniature, agile, easy to carry and deploy Autonomous Underwater Vehicle (AUV) equipped with a suite of sen ...

IEEE2018

Underwater propelling device for underwater vehicle

Alexander Bahr, Felix Stephan Schill

The present invention relates to an underwater propelling device (10) i a stator (20) comprising circumferential arrayed coils (35) and being adapted to generate a controlled electromagnetic field along an axial direction, a shaftless propellant rotor (30) ...

2016

Environmental Sensing using Land-based Spectrally-selective Cameras and a Quadcopter

Alcherio Martinoli, Michael Minnig, William Christopher Evans, Alexander Bahr

2013

Distributed spatiotemporal suppression for environmental data collection in real-world sensor networks

Alcherio Martinoli, William Christopher Evans, Alexander Bahr

Environmental processes are often severely over-sampled. As sensor networks become more ubiquitous for this purpose, increasing network longevity becomes ever more important. Radio transceivers in particular are a great source of energy consumption, and ma ...

Ieee Computer Soc2013

Evaluating Efficient Data Collection Algorithms for Environmental Sensor Networks

Alcherio Martinoli, William Christopher Evans, Alexander Bahr

Although there exists a large body of work on efficient data collection in sensor networks, the vast majority of proposed techniques have not been implemented on real networks or thoroughly studied on real data. As algorithm performance is highly dependent ...

Springer-Verlag Berlin2013

Measuring Sensible Heat Flux with High Spatial Density

Alcherio Martinoli, Marc Parlange, Wolf Hendrik Huwald, Chad Higgins, William Christopher Evans, Alexander Bahr

2012

Modeling and Benchmarking Ultra-Wideband Localization for Mobile Robots

Alcherio Martinoli, Catherine Dehollain, Edmund James Colli-Vignarelli, Alexander Bahr

Ultra-Wideband Impulse Radio (UWB-IR) is a technology that has great potential to solve numerous mobile robotic and asset tracking problems in GPS-denied environments. Our goal is to help software and hardware designers in improving the state-of-the-art in ...

2012

Low-Cost Collaborative Localization for Large-Scale Multi-Robot Systems

Alcherio Martinoli, Amanda Stella Markowska Prorok, Alexander Bahr

Large numbers of collaborating robots are advantageous for solving distributed problems. In order to efficiently solve the task at hand, the robots often need accurate localization. In this work, we address the localization problem by developing a solution ...

Ieee2012

Wireless GPS-based phase-locked synchronization system for outdoor environment

Frédéric Meyer, Thomas Lochmatter, Alexander Bahr

Synchronization of data coming from different sources is of high importance in biomechanics to ensure reliable analyses. This synchronization can either be performed through hardware to obtain perfect matching of data, or post-processed digitally. Hardware ...

2012

Toward the Deployment of an Ultra-Wideband Localization Test Bed

Alcherio Martinoli, Catherine Dehollain, Edmund James Colli-Vignarelli, Alexander Bahr

The design, development, and deployment of Ultra-Wideband (UWB) localization systems involves digital and Radio-Frequency (RF) hardware, embedded software, localization algorithms, security and reliability aspects, electromagnetics, and others. Design and ...

2011

Indoor Navigation Research with the Khepera III Mobile Robot: An Experimental Baseline with a Case-study on Ultra-wideband Positioning

Alcherio Martinoli, John Farserotu, Amanda Stella Markowska Prorok, Adrian Arfire, Alexander Bahr

Recent substantial progress in the domain of indoor positioning systems and a growing number of indoor location-based applications are creating the need for systematic, efficient, and precise experimental methods able to assess the localization and perhaps ...

2010