Motion Modeling and Control of Lower Limb Exoskeleton Based on Max-Plus Algebra

Abstract

Max-plus algebra is a special method to describe the discrete event system. In this paper, it is introduced to describe the motion of lower limb exoskeleton. Based on the max-plus algebra and the timed event graph, the walking process of exoskeleton is modelled. The max-plus algebra approach can describe the logical sequence and safety condition in the walking process, which cannot be achieved via other conventional modelling approaches. The autonomous control of lower limb exoskeleton system is studied via the model based on max-plus algebra. In the end, an FSM (finite state machine) controller embedded with the max-plus algebra model is proposed, and the experiments show ideal speed and gait/phase period control effect, as well as the good safety and stable performance.

Cassava Chips Production System in Max-Plus Algebra

“…There is related research from (Kansal & Dabas, 2021;Karadogan, 2021;Maure, Ningsi, & Nay, 2021). While max-plus algebra is the algebraic structure of the mathematical system max=ℝ∪{−∞} which is equipped with the operation, which is maximum (denoted max) and the operation, which is ordinary addition (denoted +) (Qin & Liu, 2021;Suroto, 2021). There are several previous research results that have used petri nets and max plus algebra in their research, such as research on petri net simulations in the fermented milk production process (Pramesthi, 2021); Petri net design and max-plus algebra on the blessed milk soyghurt production system (Nurmalitasari & Iswahyuni, 2019); The research from (Qin & Liu, 2021); (Pamuk, 2015); and (Konigsberg, 2013).…”