Correct-by-Construction Approach for Self-Evolvable Robots

Abstract

The paper presents a new formal way of modeling and designing reconfigurable robots, in which case the robots are allowed to reconfigure not only structurally but also functionally. We call such kind of robots "self-evolvable", which have the potential to be more flexible to be used in a wider range of tasks, in a wider range of environments, and with a wider range of users. To accommodate such a concept, i.e., allowing a self-evovable robot to be configured and reconfigured, we present a series of formal constructs, e.g., structural reconfigurable grammar and functional reconfigurable grammar. Furthermore, we present a correct-by-construction strategy, which, given the description of a workspace, the formula specifying a task, and a set of available modules, is capable of constructing during the design phase a robot that is guaranteed to perform the task satisfactorily. We use a planar multi-link manipulator as an example throughout the paper to demonstrate the proposed modeling and designing procedures. IntroductionReconfigurable robots are a family of robots that are capable of adjusting their shapes and functions to changing environments and tasks [1,2]. They are posed to meet the increasing demands of providing personal robots to adjust to individual needs and physical characteristics [3,4] as well as industrial robots to adapt to changes in the market [5]. Over the past three decades, the field of reconfigurable robots has advanced from proofs-of-concept to physical implementations. However, even with their potential versatility and robustness over conventional robots, reconfigurable robots still suffers from inferior performance, one of the main factors impeding them from practical adoption. Furthermore, existing reconfigurable robots are rarely capable of functional adaption. In this paper, we propose a formal modeling framework of reconfigurable robots that are capable of both structural and functional reconfigurations. We will also explore a design philosophy called "correct-by-construction" to guarantee the performance of the robots during the design phase.