Original Article Proc IMechE Part D: J Automobile Engineering 1–11 Ó IMechE 2020 Article reuse guidelines: sagepub.com/journals-permissions DOI: 10.1177/0954407020932676 journals.sagepub.com/home/pid Event-triggered control of vehicular platoon system with time-varying delay and sensor faults Kritika Bansal and Pankaj Mukhija Abstract This paper addresses the problem of control of a vehicular platoon system with limited on-board resources in the pres- ence of time-varying delay and sensor faults. A platoon system with predecessor-leader following topology in which each vehicle suffers from probabilistic sensor faults and time-varying delay is considered. To reduce the utilization of commu- nication and energy resources in the system, a novel event-triggering communication strategy at the sensor-controller channel is proposed. Based on the proposed triggering strategy, a criteria for co-designing of the triggering parameter and the control law ensuring internal stability of the platoon system is developed. Furthermore, additional conditions are established for the obtained controller to guarantee string stability of the platoon system. The efficacy of the proposed methodology is demonstrated through numerical simulations. Keywords Vehicle platoon control, event-triggered control, sensor faults, time delay, string stability Date received: 22 January 2020; accepted: 24 April 2020 Introduction The continuously increasing traffic congestion is a seri- ous problem around the world causing safety concerns, reduced fuel efficiency and environmental pollution. Intelligent transportation system (ITS) is an effective technology capable of improved traffic throughput, enhanced road safety and increased fuel efficiency. 1 Vehicular platoon control is an important application of ITS that helps in improving the road capacity by reducing the inter-vehicular distance. A vehicular pla- toon system is a string of two or more vehicles travel- ling with a desired velocity while maintaining an apt longitudinal spacing between successive vehicles. However, platoon control suffers from the problem of string instability. For a string unstable system, the response to disturbance in the lead vehicle gets ampli- fied as it propagates along the string. 2 This causes the emergence of traffic jams and other safety concerns, thus jeopardizing the benefits of platoon control. To avoid this phenomena, the problem of string stability (no amplification of disturbances along the string) of vehicular platoon has been widely studied in the litera- ture. 3–6 Several researchers have investigated the analysis of platoon stability based on the concept of string stability. 7 A description of the platoon system consider- ing the four-component framework, that is, node (vehi- cle) dynamics, information flow topology, inter-vehicle spacing policy and control strategy, is proposed by Li et al. 8 Ghasemi et al. 9 presents a centralized bidirec- tional control of platoon for string stability. However, centralized control needs powerful computation and communication resources along with global informa- tion of the system. In view of the availability of limited resources in a vehicular system and to increase the sys- tem reliability, the recent trend has been towards the use of distributed controllers in a platoon system. In a distributed control architecture, only local information is required for control computation. Besides reducing the usage of communication and computational resources, distributed control also helps in maintaining the privacy of the vehicle as the vehicle information is not shared on a global platform. Most common Department of Electrical & Electronics Engineering, National Institute of Technology Delhi, Delhi, India Corresponding author: Kritika Bansal, Department of Electrical & Electronics Engineering, National Institute of Technology Delhi, Delhi 110040, India. Email: kritikabansal@nitdelhi.ac.in