Localization and Follow-the-Leader Control of a Heterogeneous Group of Mobile Robots

Abstract

This paper investigates the control and localization of a heterogeneous (different sensor, mechanical, computational capabilities) group of mobile robots. The group considered here has several inexpensive sensor-limited and computationally-limited robots which follow a leader robot in a desired formation over long distances. This situation is similar to a search, de-mining, or planetary exploration situation where there are several deployable/disposable robots led by a more sophisticated leader. Specifically, the robots in this paper are designed for highway safety applications where they automatically deploy and maneuver safety barrels commonly used to control traffic in highway work zones. Complex sensing and computation are performed by the leader while the followers perform simple operations under the leader’s guidance. This architecture allows followers to be simple, inexpensive and have minimal sensors. Theoretical and statistical analysis of a tracking-based localization method is provided. A simple follow-the-leader control method is also presented. Experimental results of localization and follow-the-leader formation-motion are included.

Modelling computational requirements of mobile robotic systems using zones and processing windows

“…We extended the functionality of the RSM system by adding the capability of the RSMs to follow the lead robot in [11]. In [19], we showed how real-time scheduling analysis could be applied to a specific mobile robotic application in which the periods of tasks were dependent on the speed at which the robot was moving.…”

“…For any task in T hp , the lower bound on the period can be calculated from Equation (11), where p j is the period and e j is the worst case execution time of task T j . …”

Multi-robot caravanning

“…This technique has applications in formation control [9], multi-robot planning [3], and cooperative task execution [12]. Generally, a follower's goal is to stay within a given distance of the leader and adjust its relative angle such that the leader remains within the follower's field of view.…”

“…The current state of the art in cooperative movement [7], [12] assumes that all robots have global knowledge or that robots with global knowledge are designated as leaders beforehand. For instance, in [12], the leader is assumed to have global knowledge and precision positioning, e.g., using GPS, while followers use only simple sensors and perform simple computation to follow the leader.…”

“…In other scenarios, groups of heterogeneous robots cooperate by combining capabilities to complete tasks that could not be completed by multiple instances of just one type of robot. An example of this is demonstrated in a highway maintenance task [12], where a group of simple robots serves as safety markers, while a more sophisticated leader with global knowledge is responsible for guiding the other robots to their positions.…”