Estimating Remaining Useful Life with Linear Mixed Effects Models R package degradr version 1.0.2 Provides tools for estimating the Remaining Useful Life (RUL) of degrading systems using linear mixed-effects models and creating a health index. It supports both univariate and multivariate degradation signals. For multivariate inputs, the signals are merged into a univariate health index prior to modeling. Linear and exponential degradation trajectories are supported (the latter using a log transformation). Remaining Useful Life (RUL) distributions are estimated using Bayesian updating for new units, enabling on-site predictive maintenance. Based on the methodology of Liu and Huang (2016) <doi:10.1109/TASE.2014.2349733>. Software Depends: R (>= 4.5) Imports: dplyr, nlme, quadprog, ggplot2 Suggests: testthat (>= 3.0.0) Pedro Abraham Montoya Calzada <pedroabraham.montoya@gmail.com> Comprehensive R Archive Network (CRAN) Pedro Abraham Montoya Calzada [aut, cre, cph] (ORCID: <https://orcid.org/0009-0002-3497-210X>), Rogelio Salinas Gutiérrez [aut, cph] (ORCID: <https://orcid.org/0000-0002-1669-4460>), Silvia Rodríguez-Narciso [aut, cph] (ORCID: <https://orcid.org/0000-0001-5429-5914>), Netzahualcóyotl Castañeda-Leyva [aut, cph] (ORCID: <https://orcid.org/0000-0001-9414-3923>) GPL-3 2026-03-26 application/tgz https://CRAN.R-project.org/package=degradr doi:10.32614/CRAN.package.degradr