String stability experimentation using a low-cost mobile robotic testbed

This paper presents a practical implementation of string stability research in autonomous convoy formation that is suitable for use in a typical undergraduate project lab. The research presents a benchmark test problem that is challenging without representing a prohibitively expensive undertaking. The testbed development that is presented facilitates convoy formation, the implementation of different control laws and provides a good motivational example for a large range of complementary research themes. A case study that illustrates a loop shaping proportional plus integral control scheme is described. The example exhibits good stability and performance results that allows students to determine hard constraints on limits of convoy performance.