This article proposes a method to precisely estimate the load force of magnetic lead screw (MLS)-based series elastic actuators (SEAs) in real time. The transmissions MLS-based SEAs generally comprise permanent magnets (PMs). Owing pole distortion and characteristic nonlinear PMs, conventional estimation methods are less accurate for than with mechanical springs. In proposed method, MLSs, an ML...

The collaborative robot market has experienced rapid growth, leading to advancements in compliant actuation and torque control. Magneto-rheological (MR) clutches offer a hardware-level solution for achieving both compliance control through adjustable coupling between the input output of MR clutch. However, presence frequency-dependent magnetic hysteresis makes controlling challenging. In this p...

Let G be a finite group, p be a prime, k be an algebraically closed field of characteristic p. J. L. Alperin has conjectured that for any finite group G, # (isomorphism types of simple fcG-modules) = £ # (isomorphism types of projective simple A: (C) where the sum is taken over a set of representatives of the conjugacy classes of /7-subgroups of G. There is also a ' blockwise' version of this c...

Magnetorheological dampers have raised as promising devices for structural seismic protection since they have many attractive features such as small power requirements, reliability, and relatively low cost. These devices have strongly nonlinear behaviour which is very difficult to characterize. For this reason, the modelling of MR dampers has been an active field during the last years and has p...

Abstract—In this paper, an advanced Nonlinear Exponential Model (NEM), able to simulate the uniaxial dynamic behavior of seismic isolators having a continuously decreasing tangent stiffness with increasing displacement in the relatively large displacements range and a hardening or softening behavior at large displacements, is presented. The mathematical model is validated by comparing the exper...

We study the asymptotic behavior, as goes to 0, of a passive scalar T (x;t) solution of the following advection-diiusion equation: @T @t = 2 4T + 1 V (x; t 2) rT ; t > 0 T (x;0) = T0(x); x 2 IR d where is a strictly positive diiusion constant and fV (x; t); x 2 IR d ; t 0g is a mean zero homogeneous Gaussian eld. We assume that the covariance is of the form: IEfV (x; t)V (y; s)g = ?(x ? y) exp(...