TTW in 60 seconds
Wirelessly interconnected sensors, actuators, and controllers promise greater flexibility, lower installation and maintenance costs, and higher robustness in harsh conditions than wired solutions. However, to facilitate the adoption of wireless communication in cyber-physical systems (CPS), the functional and non-functional properties must be similar to those known from wired architectures.
We thus present Time-Triggered Wireless (TTW), a wireless architecture for multi-mode CPS that offers reliable communication with guarantees on end-to-end delays among distributed applications executing on low-cost, low-power embedded devices. We achieve this by exploiting the high reliability and deterministic behavior of a synchronous transmission based communication stack we design, and by coupling the timings of distributed task executions and message exchanges across the wireless network by solving a novel co-scheduling problem.
While some of the concepts in TTW have existed for some time and TTW has already been successfully applied for feedback control and coordination of multiple mechanical systems with closed-loop stability guarantees, this paper presents the key algorithmic, scheduling, and networking mechanisms behind TTW, along with their experimental evaluation, which have not been known so far.
Publications
ECRTS 2020, Modena, Italy (July 2020)
Paper Software Presentation Video
SenSys 2017, Deflt, The Netherlands (November 2017)
Abstract Poster
Video
Presentation at ECRTS 2020
15 minutes
Software

The TTW software have passed the ECRTS Artifact Evaluation.
TTW-Artifacts
Main repository that serves as a hub for all data and software related to the TTW project.
TTW Scheduler
The code of the TTW Scheduler is available in a dedicated repository. The scheduler is implemented in Matlab and relies on the Gurobi solver.
TTW in Action
TTW has been instrumental to the first demonstration of feedback control and coordination of multiple mechanical systems with closed-loop stability guarantees distributed over a mobile and multi-hop wireless network.
- Best Paper Award at ICCPS 2019 and corresponding journal extension
- Best Demo Award at IPSN 2019 (see video below)
- 2019 Zukunftpreis ("future award") from the Ewald Marquardt Foundation
The following video (1'30") briefly presents the IPSN 2019 Demo.
People
- Romain Jacob (lead) - ETH Zürich
jacobr at ethz dot ch
- Licong Zhang - TU München
- Marco Zimmerling - TU Dresden
- Jan Beutel - ETH Zürich
- Samarjit Chakraborty - University of North Carolina at Chapel Hill
- Lothar Thiele - ETH Zürich