title: Aperiodic linear networked control considering variable channel delays: application to robots coordination.
abstract: One of the main challenges in wireless cyber-physical systems is to reduce the load of the communication channel while preserving the control performance. In this way, communication resources are liberated for other applications sharing the channel bandwidth. The main contribution of this work is the design of a remote control solution based on an aperiodic and adaptive triggering mechanism considering the current network delay of multiple robotics units. Working with the actual network delay instead of the maximum one leads to abandoning this conservative assumption, since the triggering condition is fixed depending on the current state of the network. This way, the controller manages the usage of the wireless channel in order to reduce the channel delay and to improve the availability of the communication resources. The communication standard under study is the widespread IEEE 802.11g, whose channel delay is clearly uncertain. First, the adaptive self-triggered control is validated through the TrueTime simulation tool configured for the mentioned WiFi standard. Implementation results applying the aperiodic linear control laws on four P3-DX robots are also included. Both of them demonstrate the advantage of this solution in terms of network accessing and control performance with respect to periodic and non-adaptive self-triggered alternatives.
authors.affiliation: Electronics Department, Polytechnics School, University of Alcala, Campus Universitario, Ctra. Madrid-Barcelona, Km. 33,600, 28871. Alcalá de Henares, Madrid, Spain. carlos.santos@depeca.uah.es.
authors.forename: Carlos
authors.initials: C
authors.lastname: Santos
authors.affiliation: Electronics Department, Polytechnics School, University of Alcala, Campus Universitario, Ctra. Madrid-Barcelona, Km. 33,600, 28871. Alcalá de Henares, Madrid, Spain. espinosa@depeca.uah.es.
authors.forename: Felipe
authors.initials: F
authors.lastname: Espinosa
authors.affiliation: Electronics Department, Polytechnics School, University of Alcala, Campus Universitario, Ctra. Madrid-Barcelona, Km. 33,600, 28871. Alcalá de Henares, Madrid, Spain. santiso@depeca.uah.es.
authors.forename: Enrique
authors.initials: E
authors.lastname: Santiso
authors.affiliation: Delft Center of Systems and Control, Delft University of Technology, Mekelweg 2, 2628 CD Delft, The Netherlands. M.Mazo@tudelft.nl.
authors.forename: Manuel
authors.initials: M
authors.lastname: Mazo
keywords: adaptive self-triggered control; aperiodic control implementation; networked robots; variable channel delays; wireless cyber-physical systems