Experimental verification of a scalable protocol for vehicle platooning

This paper is concerned with a recently proposed scalable protocol for vehicle platooning, known as the serial consensus protocol. This achieves coordination of second-order integrator systems through a series connection of first-order conventional consensus protocols, and has been theoretically shown to have advantageous stability and performance properties. We implement this protocol on a vehicle platoon of five robots in a lab setting, where it is subject to measurement noise. We present experimental verification that the system is scalably stable, which is in accordance with theoretical findings. Moreover, we show theoretically that the parameters for which scalable stability occurs can be relaxed when information of the communication topology is available, which is also verified experimentally. In parallel, a conventional consensus protocol is implemented, which is known to not be scalably stable, which we also demonstrate in experiments. Lastly, we implement experiments to demonstrate the string stable behavior of the the serial consensus protocol in directed vehicle platoons, as predicted by theory, which again does not hold for conventional consensus.