All posts tagged: sync

Robots that sync and swarm: A proof of concept in ROS 2

A unified mathematical model for synchronisation and swarming has been proposed recently. Each system entity, called “swarmalator”, coordinates its internal phase and location with the other entities in a way that these two attributes are mutually coupled. This paper realises and studies, for the first time, the concept of swarmalators in technical systems. We adapt and extend the original model for its use on mobile robots and implement it in the Robot Operating System 2 (ROS 2). Simulations and experiments with small robots demonstrate the feasibility of the model and show its potential to be applied in real-world systems. All types of space-time patterns achieved in theory can be reproduced in practice. Applications can be found in monitoring, exploration, entertainment and art, among other domains.

Z1 Sensor Nodes

Synchronization in sensor networks using time series analysis

Time synchronization is an essential building block in wireless sensor networks but is challenging due to low-precision oscillators and limited computational power of cheap devices. A novel synchronization solution for such scenarios is now proposed by Wasif Masood together with his advisors Christian Bettstetter and Jorge F. Schmidt from the University of Klagenfurt.

Synchronization with phase rate correction

Synchronization algorithms based on the theory of pulse-coupled oscillators are evaluated on programmable radios. It is experimentally demonstrated that the stochastic nature of coupling is a key ingredient for convergence to synchrony. We propose a distributed algorithm for automatic phase rate equalization and show that synchronization precisions below one microsecond are possible.

Programmable radio boards (WARP)

Pulse-coupled oscillator synchronization on FPGA radios

The mathematical modeling of pulse-coupled biological oscillators offers a fully decentralized and scalable approach for time synchronization. There is a broad spectrum of work on pulse-coupled oscillators in physics, biology, neuroscience, and other disciplines. The communications engineering community has been interested to transfer these results to the synchronization of nodes in wireless networks. A one-to-one transfer is infeasible due to the differences between wireless and biological communications. Several extensions and modifications are required with respect to delays, noise, multihop communications, and sync words.

Synchronization in networks with stochastic interactions

Synchronization emerges in a variety of systems ranging from fireflies and neural networks in biology, to coupled lasers, wireless communication, and Josephson junctions in physics and engineering. Sometimes the goal is to avoid synchrony, e.g., during Parkinson tremor or epileptic seizures, sometimes to achieve synchrony, e.g., in heart pacemakers, lasers, electric power grids and communication technologies. In the growing field of wireless embedded systems, a self-organizing approach to achieve synchrony seems to be a promising way of arranging slots and frames for data packet transmission without reference to a central unit. Such self-organized dynamics should quickly adjust to changes and be scalable to large networks.

Self-organizing synchronization: Convergence, paper, scholarship

The synchronous flashing of fireflies is a spectacular example for self-organization in nature. Thousands of fireflies gather in trees and flash in unison using a distributed mechanism that can be understood using the theory of coupled oscillators. This theory has successfully been used for modeling many other synchronization and coordination phenomena, such as sleep cycles, firing of neurons, and vibration of bridges.

Talk at “Future of Networks” symposium

The annual ITG symposium on future perspectives of communication networks will this year focus on Self-Organization: Opportunities and Challenges. To be held in Stuttgart on October 7, it will cover a broad variety of topics and a well-balanced set of speakers, not only from academia but also from industry. The keynote speech will be given by the perspective of Deutsche Telekom. The strong industry participation highlights the timeliness and importance of the topic self-organization in industry. Bettstetter will give a talk Self-Organizing Synchronization: From Fireflies to Wireless Systems, which will include a live synchronization experiment.